MXPA06011226A - Plants having improved growth characteristics and method for making the same - Google Patents

Abstract

The present invention concerns a method for improving growth characteristics of plants by modulating expression of a nucleic acid sequence encoding a NAP1-like protein. The invention also relates to transgenic plants having improved growth characteristics, which plants have modulated expression of a nucleic acid encoding a NAP1-like protein.

Description

PLANTS THAT HAVE IMPROVED GROWTH CHARACTERISTICS AND METHOD TO MAKE THEMSELVES The present invention relates to a method for improving growth characteristics, and in particular to increase the yield of a plant. More specifically, the present invention relates to a method for increasing performance by modulating the expression in a plant of a nucleic acid encoding a protein homologous to Protein 1 of Nucleosome Assembly (protein similar to NAP1). The present invention also relates to plants that have modulated expression of a nucleic acid encoding a NAP1-like protein, whose plants have increased yield related to corresponding wild-type plants. Given the increasing world population, and the decreasing area of land available for agriculture, a greater purpose persists to improve the efficiency of agriculture and to increase the diversity of plants in horticulture. Conventional media for cultivation and horticultural improvements utilize selective breeding techniques to identify plants that have desirable characteristics. However, such selective breeding techniques have several disadvantages, ie, that these techniques are normally labor-intensive and result in plants that often contain heterogeneous genetic complements that may not always result in the desirable trait that is transmitted from progenitor plants. Advances in molecular biology have allowed humanity to manipulate the germ plasm of animals and plants. Plant genetic engineering involves the isolation and manipulation of genetic material (usually in the form of DNA or RNA) and the subsequent introduction of that genetic material into a plant. Such technology has led to the development of plants that have several improved economic, agronomic or horticultural traits. Traits of particular economic interest are growth characteristics such as high yield. NAP proteins form a family of related proteins that are known in animals and are reported to be involved in chromatin-related activities. The NAP protein family is characterized by the presence of a conserved sequence known as the NAP domain. The NAP domain is described in the databases Pfam (access PF00956) and Interpro (access IPR002164). NAP is a component of a multifactor complex that mediates the packaging of DNA within nucleosomes (Krude, T. and Keller, C. (2001) Cell, Mol.Life Sci. 58, 665-672). During the S phase of the eukaryotic cell division cycle, newly replicated DNA rapidly assembles into chromatin. This process requires the coordinated action of several factors. In the initial stages, CAF1 (chromatin assembly factor 1) binds histone H3 and H4 proteins and directs them to the junction of replication through PCNA binding. The subsequent deposition of histone H2A and H2B proteins is mediated by NAP1 proteins. NAP1 was first described in HeLA cells (von Lindern et al., (1992) Mol, Cell, Biol. 12, 3346-3355) and was found to be conserved later in all eukaryotes. In addition, it is thought that NAP proteins regulate genetic transcription and can influence cell differentiation and development. SET proteins are highly related to NAP proteins and play a role in several cellular processes in humans. In human cells, SET has been shown to associate with several CDK-cyclin complexes during cell cycle regulation, such as G2 / M transition. SET is a potent protein phosphatase 2A inhibitor (PP2A) that is involved in several signaling pathways. The inhibitory activity of SET could be attributed to an acidic Terminal-C domain (Canela et al. (2003) J. Biol. Chem. 278, 1158-1164). Other reports show the involvement of SET in the repair and transcription of DNA. SET is a part of a complex that has DNA binding and bending activities mediated by chromatin-associated HMG2 protein. HMG2 facilitates the assembly of higher-order nucleoprotein structures by folding and interlacing DNA or by stabilizing unbound DNA. The co-precipitates HMG2 with SET (Fan et al. (2002) Mol. Cell. Biol. 22, 2810-2820). SET was also reported to inhibit the demethylation of active DNA (Cervoni et al (2002) J. Biol. Chem. 277, 25026-25031). The oncoprotein Set / TAF-I, involved in the inhibition of histone acetylation, also inhibits the demethylation of ectopically methylated DNA resulting in genetic silencing. Set / TAF-I is suggested to play a role in the integration of epigenetic states of histones and DNA in genetic regulation. The NAP1 protein activity is regulated in part by phosphorylation. It was shown that the subcellular localization of NAP1 in Drosophila is dependent on its phosphorylation status, which can be controlled by Casein Kinase II (Rodríguez et al (2000) J. Mol. Biol. 298, 225-238). It is reported that mammals possess several NAP1 proteins, while there is only one known NAP1 protein in yeast. Plant NAP1 orthologs are still largely unknown, although NAP1 proteins were reported from soybeans (Yoon et al (1995) Mol, Gen. Genet 249, 465-473), Arabidopsis, tobacco, corn and rice (Dong et al. (2003) Plant 216, 561-570). The phylogenetic analysis of genes similar to NAP1 of the plant has revealed that there are two sub-groups, one related to NAP1 and the other to the SET protein (Figure 1). More likely, the subsequent sequence divergence may have occurred since the two Arabidopsis, the two groups of maize sequences and two tobacco groups together are geared towards a more recent gene-doubling effect. The genome of Saccharomyces cerevisiae contains only one gene encoding NAP, combining the functional properties of both subgroups of NAP1 and SET. Similarly, Factor 1 Activating Template (TAF-I), a homolog of NAP1, combines both activity that inhibits PP2a (Saito et al., Biochem. Biophys. Res. Comm. 259, 471-475, 1999 ) as the chromatin remodeling activity (Kawase et al., Genes Cells 1, 1045-1056, 1996). It is therefore likely that the plant proteins of the NAP / SET family are largely redundant in function, particularly in the group of SET proteins where a lower degree of divergence is observed compared to the NAP group. In addition, there is structural evidence that the NAP and SET proteins belong to the same family since they share the NAP domain which is followed by a terminal acidic region. As is known about the function of NAP1-like proteins in plants, although a role in mitosis and cytokinesis has been proposed (Dong et al 2003). Plant orthologs of the NAP1 protein most likely play a different role than their animal counterparts. Based on its nuclear localization and sequence similarities with mammalian SET protein, a role in chromatin remodeling can be expected for plant proteins. In addition, the NAP / SET group of protein plants could be involved in the regulation of PP2A in plants. PP2A is one of the largest plant phosphatases, acting broadly on transcription factors and protein kinases, and proposes to regulate the activity of proteins involved in a variety of cellular processes, including the cell cycle (Ayaydin et al (2000 ) Plant J. 23, 85-96), hormonal actions such as ABA-mediated stomach movement, germination (Kwak et al. (2002) Plant Cell 14, 2849-2861) or auxin transport and root development (Garbers et al. to 1996 EMBO J. 15, 2115-2124). PP2A is further reported to be involved in photosynthesis and light signaling (Sheen (1993) EMBO J. 12, 3497-3505) and in nitrogen uptake (Hirose and Yamaya (1999) Plant Physiology 121, 805-812). To date, no effects on agronomic traits have been described in modulating the expression of NAP1-like proteins in plants. It has now surprisingly been found that modulating the expression of a nucleic acid encoding a NAP1-like protein in a plant gives plants that have improved growth and development, in particular increased yield, more particularly increased seed yield when compared to plants of type corresponding wild. Therefore, according to a first embodiment of the present invention there is provided a method for improving the growth and development of a plant, which comprises introducing a genetic modification in a plant and selecting for modulated expression in this plant an acid sequence. nucleic acid that encodes a protein similar to NAPl. In particular, improved growth and development is the increased yield of a plant, more particularly increased seed yield; and the modulated expression is the increased expression. The term "NAP1-like protein", as defined herein, refers to any protein comprising a NAP domain and an acidic Terminal-C region and having phosphatase inhibition activity PP2a. The term "NAP domain" as used herein is as defined by the Pfam database by accession number PF00956 (http: // www. Sanger.ac.uk / Software / Pfam /; Bateman et al. ., Nucleic Acids Research 30 (1): 276-280 (2002), see for example, Table 1). Preferably, the NAP1-like protein sequences useful in the present invention have a NAP domain that comprises a unique characteristic (T / S) FF (T / N / S / E / D) (W / F) (L / F) and / or the amino acid sequence conserved as given in SEQ ID. NO: 33. More preferably, the NAP domain is as represented by the IDENT SEC. NO: 32. The term "acidic C-terminal region" or "acidic C-terminus" as used herein refers to the carboxy terminal end of the protein, whose terminal carboxy terminal is approximately 20 to 25 amino acids long, of which at least 13 residues are glutamic and / or aspartic acid.

Table 1: Examples of Arabidopsis proteins comprising a NAP1 domain Optionally, the NAP1-like protein useful in the methods of the present invention has, in addition to being an inhibitor of PP2a phosphatases, also chromatin remodeling activities. Methods for measuring inhibition of PP2a phosphatases are known in the art and comprise, for example, substrate-based assays or commercially available fluorochrome-labeled or ink-labeled assays based on the measurement of radioactivity in soluble TCA fractions after the treatment of histone Hl labeled with [32 P] with phosphatase PP2a (Saito et al. (1999) Biochem. Biophys. Res. Comm. 259, 471-475) or radioactivity released from myelin basic protein (Li et al, J. Biol. Chem. 271, 11059-11062, 1996). An alternative method for measuring the activity of the NAP1-like protein is given in Example 6, which is based on the method described by Ulloa et al. (FEBS Leters 330, 85-89, 1993). Chromatin remodeling activities can be evaluated in several ways, such as the measurement of DNA binding activity in a gel retardation assay (Fan et al., 2002) or as the measurement of histone binding activity using ELISA (Rodríguez et al. (1997) Genomics 44, 253-265). The activity of DNA bending can be determined in a ligase-mediated circularization assay (Fan et al., 2002) or in a super-coiled test (Fuji-Nakata et al. (1992) J. Biol. Chem. 267, 20980-20986; Yoon et al. (1995), Mol. Gen. Gen. 249.465-473). Preferably, the NAP1-like protein, comprising a NAP domain and an acidic C-terminal region as described above, is of plant origin. The NAP1-like protein is preferably from a dicotyledonous plant, preferably from the Brassicaceae family, more preferably from Arabian diphysis thaliana, more preferably the NAP1-like protein is a protein as represented by SEQ. FROM IDENT. DO NOT. : 2 or is a homologue, derivative or active fragment thereof, which homologs, derivatives or active fragments comprise a NAP domain and the acidic C-terminus as described above, and whose homologs, derivatives or active fragments further have activity to inhibit PP2A. Preferably the NAP1-like proteins are encoded by a nucleic acid as represented by SEQ. FROM IDENT. NO .: 1 or a nucleic acid capable of hybridizing with these. The term "NAP1-like protein" includes proteins homologous to the protein presented in SEC. FROM IDENT. NO .: 2. Preferred homologs that are used in the methods of the present invention comprise a NAP domain and an acidic C-terminus as described above. Preferably, the homologs have a NAP domain that comprises a unique characteristic (T / S) FF (T / N / S / E / D) (W / F) (L / F) and / or the conserved sequence of the SEC. FROM IDENT. NO .: 3, and an acidic C-terminus of 20 to 25 residues comprising at least 13 residues of aspartic and / or glutamic acid. Additionally, NAP1 homologs have activity to inhibit PP2a and optionally also possess chromatin remodeling activities, which can be measured as described above. The counterparts of the SEC. FROM IDENT. DO NOT. : 2 can be found in several eukaryotic organisms. The closest homologs are usually found in the plant kingdom. The counterparts of the SEC. FROM IDENT. DO NOT. Suitable in the methods of the present invention include two tobacco proteins (SEQ ID NO: 7 and 9), a tomato protein (SEQ ID NO: 23), an alfalfa protein ( SEQ ID NO: 11), the AraJídopsis protein represented by SEC. FROM IDENT. NO .: 21. Other homologs suitable for practicing the method according to the invention include for example the homologues of Zea mays nfal04 (Accession No. AF384036, SEQ ID NO: 13) and nfal03 (Accession No. AF384035, SEQ ID NO: 19); or the Oryza sativa homologs (SEQ ID NO: 15 and 17). Methods for the search and identification of NAP1-like homologs would be suitable within the realm of persons skilled in the art. Such methods comprise comparison of the sequences represented by the SEC. FROM IDENT. DO NOT. : 1 or 2, in a computer readable format, with sequences that are available in public databases such as MIPS (http: // mips. gsf .de /), GenBank (http: // www. ncbi nim.ih.gov / Genbank / index.html) or Base EMBL Nucleotide Sequence Data (http: // ww.ebi.ac.uk / embl / index.tml), using algorithms well known in the art for aligning or aring sequences, such as GAP (Needleman and Wunsch, J. Mol. Biol. 48; 443-453 (1970)), BESTFIT (using the local homology algorithm of Smith and Waterman (Advances in Applied Mathematics 2; 482-489 (1981))), BLAST (Altschul, SF, Gish, W., Millar , W., Myers, EW &Lipman, DJ, J. Mol. Biol. 215: 403-410 (1990)), FASTA and TFASTA (WR Pearson and DJ Lipman Proc. Nati .Acad. Sci. USA 85: 2444 -2448 (1988)). The software to perform the BLAST analysis is publicly available through the National Center for Biotechnology Information. The aforementioned homologs were identified using predetermined blast parameters (BLASUM62 matrix, 11 gap gap penalty and 1 gap extension penalty) and preferably full length sequences are used for analysis. Alternatively, only the domain of NAP1 can be used for arison, since this domain rises most of the protein. "Homologs" of a NAP1-like protein enasses peptides, oligopeptides, polypeptides, proteins and enzymes having amino acid substitutions, deletions and / or insertions relative to the unmodified protein in question and having similar biological and functional activity as the unmodified protein from which they are derived. To produce such homologues, the amino acids of the protein can be replaced by other amino acids that have similar properties (such as similar hydrophobic character, hydrophilic character, antigenicity, propensity to form or divide α-helical structures of β-sheet structures). Conservative substitution tables are well known in the art (see, for example, Creighton (1984) Proteins, W. H. Freeman and any). Homologs useful in the method according to the invention have at least 50% identity or sequence similarity (functional identity 9 to the protein sequence as depicted in SEQ ID NO: 2 (Access GénBank NP_177596), alternatively at least 60% or 70% identity or sequence similarity to SEQ ID NO: 2. Typically, homologs have at least 80% identity or sequence similarity, preferably at least 85% identity or sequence similarity, more preferably at least 90% sequence identity or similarity, more preferably at least 95%, 96%, 97%, 98% or 99% identity or sequence similarity to SEQ ID NO. .: 2. Alternatively, homologs useful in the method according to the invention have at least 40% identity or sequence similarity (functional identity) to the protein sequence as represented in the GenBank access NP_56884 (SEQ ID. NO .: 29), alternatively and at least 50%, 60% or 70% identity or sequence similarity to the SEC. FROM IDENT. NO .: 29. Normally, homologs have at least 80% identity or sequence similarity to the SEC. FROM IDENT. DO NOT. : 29, preferably at least 85% identity or sequence similarity, preferably in addition at least 90% identity or sequence similarity, more preferably at least 95%, 96%, 97% or 99% identity or similarity of sequence to the SEC. FROM IDENT. NO .: 29. Percent identity can be calculated from sequences of full-length proteins or with certain regions (preferably conserved) of such sequence, using alignment programs based on the Needleman and Wunsch algorithm (such as GAP), using a GLOSUM62 matrix, an opening gap penalty of 10 and a gap extension penalty of 0.5. For example, the NAP domain as given in the SEC. FROM IDENT. NO .: 32 can be used as a query. The identification of such domains in a protein sequence would be suitable within the domain of the person skilled in the art and involves a uter readable format of the nucleic acids used in the methods of the present invention., the use of alignment software programs and the use of publicly available information in protein domains, themes and conserved blocks. An integrated search can be done using the INTERPRO database (Mulder et al., (2003) Nucí Acids Res. 31, 315-318, http: // www.ebi .ac .uk / interpro / sean.html) which combines several databases in protein families, domains and functional sites, such as PRODOM databases (Servant et al., (2002) Briefings in Bioinformatics 3,246-251, http: // prodes. toulouse. inra. /prodom/2002.1/html/home.php), PIR (Huang et al. (2003) Nucí Acids Res. 31, 390-392, http: // pir.georgetown.edu/) or Pfam (Bateman et al. (2002) Nucí Acids Res. 30, 276-280, http://pfam.wustl.edu/). Sequence analysis programs designed to search for topics can be used to identify fragments, regions and conserved domains as mentioned above. Suitable computer programs include for example MEME (Bailey and Elkan (1994) Proceedings of the Second International Conference on Intelligent Systems for Molecular Biology, pp. 28-36, AAAI Press, Menio Park, California, http: // meme.sdsc edu / meme / website / intro.html). The homologous proteins can be grouped into "protein families". A family of proteins can be defined by functional similarity and sequence analysis, such as, for example, Clustal W. A neighbor binding tree of homologous proteins similar to NAP1 can be generated by the Clustal W program and gives a good overview of its structural and ancestral relationship. In a particular embodiment of the present invention, the NAP1-like homolog (s) belongs to the same family of proteins as the protein corresponding to SEC. OF IDEN. DO NOT . : 2. In the Arabidopsis genome, two members of the NAP1-like protein family were identified (NM_177596 (SEQ ID NO: 2), NP_564063 (SEQ ID.

NO .: 21)). Members of the NAP1-like protein family can also be identified in other plants such as rice or other monocotyledonous plants. Advantageously, these family members are also useful in the methods of the present invention. Two special forms of homology, orthologs and parologists are evolutionary concepts used to describe ancestral relationships of genes. The term "paralogs" is related to homologous genes that result from one or more gene duplications within the genome of a -species. The term "ortholog" is related to the homologous genes in different organisms due to the ancestral relationship of these genes. The term "homologs" as used herein also encompasses the paralogs and orthologs of the proteins useful in the methods according to the invention. Orthologous genes can be identified by consulting one or more gene databases with a gene query of interest using, for example, the BLAST program. The higher averaged object genes that result from the search are also again subjected to a BLAS analysis, and only those object genes that match again with the query gene are retained as the real orthologous genes. For example, to find a rice ortholog from an Arabidopsis thaliana gene, a BLASTIN or TBLASTX analysis can be performed on a rice database (such as (but not limited to) the Nipponbare database of Oryza sativa available at NCBI (http: // www. Ncbi .nim.nih.gov) or rice genomic sequences (cultivars indica or japonica)). In a next step, the obtained rice sequences are used in a reverse BLAST analysis using an Arabidopsis database. The results can also be refined when the resulting sequences are analyzed with ClustalW and visualized in a neighboring binding branch. This method can be used to identify orthologs from many different species. "Homologs" of a class of NAP1 encompass proteins that have substitutions, insertions, and / or amino acid deletions, relative to the unmodified protein in question. "Substitutional variants" of a protein are those in which at least one residue in an amino acid sequence has been removed and a different residue has been inserted in its place. Amino acid substitutions are usually single residues, but can be grouped depending on the functional constraints placed on the polypeptide; the inserts will usually be in the order of about 1 to 10 amino acid residues, and the eliminations will vary from about 1 to 20 residues. Preferably, the amino acid substitutions comprise conservative amino acid substitutions. "Insertion variants" of a protein are those in which one or more amino acid residues are introduced into a predetermined site in a protein. The inserts may comprise amino-terminal and / or carboxy-terminal fusions as well as single or multiple intra-sequence amino acid insertions. Generally, the insertions within the amino acid sequence will be smaller than the amino or carboxy-terminal fusions. Examples of amino or carboxy-terminal fusion proteins or peptides include the binding domain or the activation domain of a transcriptional activator as used in the system of yeast two hybrids, phage coated proteins, (histidine) 6 tag, glutathione S-transferase label, protein A, maltose binding protein, dihydrofolate reductase, label epitope-100, c-myc epitope, FLAT® epitope, lacZ, CMP (calmodulin binding peptide), HA epitope, protein C epitope and VSV epitope. The "Elimination variants" of a protein are characterized by the removal of one or more amino acids from the protein. Amino acid variants of a protein can be easily made using synthetic peptide techniques well known in the art, such as solid phase peptide synthesis and the like, or by recombinant DNA manipulations. Methods for manipulating DNA sequences for substitution, insertion or deletion variants of a protein are well known in the art. For example, techniques for making substitution mutations at predetermined sites in DNA are well known to those of skill in the art and include M13 mutagenesis, mutagenesis in vi tro of Gen T7 (USB, Cleveland, OH), Site Directed Mutagenesis QuickChange ( Stratagene, San Diego, CA), site-directed mutagenesis mediated by PCR or other site-directed mutagenesis protocols. The term "derivatives" of a NAP1-like protein refers to peptides, oligopeptides, polypeptides, proteins and enzymes which may comprise substitutions, deletions or additions of naturally occurring and unnatural amino acid residues compared to the amino acid sequence of the naturally occurring form of the NAP1-like protein (such as the protein presented in SEQ ID NO: 2). "Derivatives" of a protein encompass peptides, oligopeptides, polypeptides, proteins and enzymes which may comprise altered, glycosylated, acylated or unnatural amino acid residues compared to the amino acid sequence in a naturally occurring form of the polypeptide. A derivative may also comprise one or more non-amino acid substituents compared to the amino acid sequence from which, for example, a reporter molecule or another ligand is derived, covalently or non-covalently linked to the amino acid sequence such as, for example, a reporter molecule which binds to facilitate its detection, and amino acid residues that do not occur naturally in relation to the amino acid sequence of a naturally occurring protein. The "active fragments" of a NAP1-like protein encompass at least the amount of amino acid residues, sufficient to retain biological and / or functional activity compared to the naturally occurring protein. A preferred active fragment of a NAP1-like protein comprises at least one NAP domain (Pfam 00956) and an acidic C-terminal domain enriched in D and / or E residues as described above, a more preferred active fragment further comprises the conserved sequence of the SEC. FROM IDENT. DO NOT. : 33. The term nucleic acid / gene similar to NAP1, as defined herein, refers to any nucleic acid encoding a NAP1-like protein as defined above, or the complement thereof. The nucleic acid can be derived (either directly or indirectly (if subsequently modified)) from any source as long as the nucleic acid, when expressed in a plant, leads to modulated expression of a nucleic acid / gene similar to NAP1 or a modulated activity and / or protein levels similar to NAPl. The nucleic acid can be isolated from a eukaryotic source, such as a yeast or fungus, plants (including algae) or animals (including humans). This nucleic acid can be substantially modified from its native form in the composition and / or the genetic environment through deliberate human manipulation. The nucleic acid sequence is preferably a homologous nucleic acid sequence, i.e. a nucleic acid sequence encoding a protein structurally and / or functionally related to SEC. FROM IDENT. NO .: 2, preferably obtained from a plant, either from the same plant species or different. Preferably, the nucleic acid is as represented by SEC. FROM IDENT. DO NOT. : l or a portion thereof or a nucleic acid capable of hybridizing thereto, which hybridizes to the sequence encodes proteins having NAP1-like protein activity as described above; or its nucleic acid encoding an amino acid represented by SEC. FROM IDENT. DO NOT. : 2 or that encodes a homologue, derivative or active fragment thereof. This term also encompasses variants of the nucleic acid encoding a NAP1-like protein due to the degeneracy of the genetic code; allelic variants; and different splice variants of the nucleic acid encoding a NAP1-like protein, including variants that are interrupted by one or more intervening sequences. Advantageously the method according to the present invention can also be practiced using portions of a nucleic acid sequence encoding a NAP1-like protein as defined above, such as the NAP1-like protein encoded by SEQ. FROM IDENT. DO NOT. : 1, or by using sequences that hybridize to a nucleic acid sequence encoding a NAP1-like protein as defined above, such as SEQ. FROM IDENT. DO NOT. : 1, preferably under stringent conditions, (which hybridize proteins encoded by sequences having activity similar to NAP1), or by using nucleic acids encoding homologs, derivatives or active fragments of a NAP1-like protein, such as that represented by SEC. FROM IDENT. DO NOT . : 2. The portions of the DNA sequence refer to a piece of DNA derived or prepared from an original (larger) DNA molecule, whose DNA portion, when expressed in a plant, results in plants that they have improved growth characteristics. Preferably, the improved growth characteristics are of increased yield, more preferably of increased seed yield, more preferably the increased seed yield comprises one or more of an increased rate of harvest, an increased total seed weight and an increased number of seeds. full seeds. The portion may comprise many genes, with or without additional control elements, or may contain only spawning sequences etc. The present invention also encompasses nucleic acid sequences capable of hybridizing to a nucleic acid sequence encoding a NAP1-like protein, whose nucleic acid sequences may also be useful for practicing the methods according to the invention. The term "hybridization" as defined herein is a process wherein the substantially homologous complementary nucleotide sequences harden each other. The hybridization process can occur completely in solution, that is, both complementary nucleic acids are in solution. Molecular biology tools that are based on such a process include the polymerized chain reaction (PCR, and all methods are based on it), subtractive hybridization, random primer extension, SI nuclease mapping, primer extension, reverse transcription, cDNA synthesis, differential display of RNAs, and DNA sequence determination. The hybridization process can also occur with one of the complementary nucleic acids immobilized to a matrix such as magnetic beads, sepharose beads or any other resin. The tools in molecular biology that are based on such a process include the isolation of poly (A +) mRNA. The hybridization process may further occur with one of the complementary nucleic acids immobilized to a solid support such as a nitrocellulose or a nylon membrane or immobilized for example, by photolithography to eg a siliceous glass support (the latter known as or nucleic acid microarrays or as nucleic acid fragments). Molecular biology tools that are based on such a process include RNA or DNA gel transfer analysis, colony hybridization, plaque hybridization, in situ hybridization and microarray hybridization. In order to allow hybridization to occur, the nucleic acid molecules are denatured in general thermally or chemically to melt a double strand into two single strands and / or to remove hairpins or other secondary structures from single-stranded nucleic acids. Hybridization severity is influenced by conditions such as temperature, saline concentration and hybridization buffer composition. For applications requiring high selectivity, it would normally be desirable to employ relatively severe conditions to form the hybrids, for example, relatively low salt and / or high temperature conditions, such as those provided by about 0.02 M to about 0.15 M NaCl, will be selected. temperatures from about 50 ° C to about 70 ° C. High stringency conditions for hybridization thus include high temperature and / or low salt concentration (the salts include NaCl and Na3 citrate) but may also be influenced by the inclusion of formamide in the hybridization buffer and / or decrease the concentration of compounds such as SDS (sodium dodecyl sulfate) in the hybridization buffer and / or the exclusion of compounds such as dextran sulfate or polyethylene glycol (promoting molecular agglomeration) from the hybridization buffer. Hybridization conditions of sufficiently low severity are particularly preferred for the isolation of nucleic acid homologs to the DNA sequences useful in the methods of the invention defined supra. Elements that contribute to homology include allelism, degeneration of the genetic code and differences in the use of the preferred codon. The presence of monovalent cations in the hybridization solution reduces the electrostatic repulsion between two strands of nucleic acid, thereby promoting the formation of hybridization; this effect is visible for sodium concentrations of up to 0.4M. Formamide reduces the fusion temperature of DNA-DNA and DNA-RNA duplexes with 0.6 to 0.7 ° C for each percentage of formamide, and in addition to 50% of formamide allows the hybridization to be carried out at 30 to 45 ° C, although the hybridization index will be decreased. Uncoupling of base pairs reduces the hybridization index and the thermal stability of the duplexes. On average and for large probes, the Tm (temperature under defined ionic strength and pH, at which 50% of the target sequence hybridizes to a perfectly coupled probe) decreases approximately 1 ° C per% base decoupling. "Severe hybridization conditions" and "severe hybridization washing conditions" in the context of nucleic acid hybridization experiments such as Southern and Northern hybridizations are dependent sequences and are different under different environmental parameters. For example, longer sequences hybridize specifically at higher temperatures. The specificity is normally the function of post-hybridization washes. Critical factors for such washes include the ionic strength and the temperature of the final wash solution. Generally, severe conditions are selected to be approximately 50 ° C lower than the thermal melting point ™ for the specific sequence at a defined ionic strength and pH. The Tm is dependent on the solution conditions and the base composition of the probe, and can be calculated using the following equation: Tm = 79.8 ° C + (18.5xlog [Na +]) + (58.4 ° C x% [G + C] ) - (820x (# pb in duplex) "1) - (0.5x% formamide) From the alternative formula, depending on the types of hybrids, are known in the art, for example: • DNA-DNA hybrids (Meinkoth and Wahl, Anal. Biochem., 138: 267-284, 1984): Tm = 81.5 ° C + 16. dxlog [Na +] + 0.41x% [G / Cb] -500x [Lc] _1 - 0.61x% formamide • DNA-RNA or RNA-RNA hybrids: Tm = 79.8 + 18.5 (log? 0 [Na +] a) + 0.58 (% G / Cb) + 11.8 (% G / Cto) 2 -820 / Lc • Oligo- hybrids DNA or oligo-ARNd: For <20 nucleotides: Tm = 2 (ln) For 20-35 nucleotides: Tm = 22 + 1.46 (/ n) ao for another monovalent cation, but only accurate in the range 0.01-0.4 M. b only accurate for GC% in the range of 30% to 75% c L = duplex length in base pairs d Oligo, oligonucleotide, ln, effective length of primer = 2x (No. of G / C) - (No. of AT / C) Note -, for each 1% of formamide, the Tm is reduced by approximately 0.6 to 0.7 ° C, while the presence of 6M urea reduces the Tm by about 30 ° C. The most preferred severe conditions are when the temperature is 20 ° C below the Tm, and the most preferred severe conditions are when the temperature is 10 ° C below the Tm. The non-specific binding can also be controlled using any of a number of known techniques such as, for example, blocking the membrane with solutions containing protein, additions of RNA, DNA and heterologous SDS to the hybridization buffer, and treatment with RNase. Washing conditions are usually carried out at or below the severity of hybridization. In general, severe conditions suitable for nucleic acid hybridization assays or genetic gene amplification detection methods are as set forth above.

More or less severe conditions can also be selected. For the purposes of defining the level of severity, reference may conveniently be made to Sambrook et al. (2001) Molecular Cloning; a laboratory manual, 3rd edition Cold Spring Harbor Laboratory Press, CSH, New York or Current Protocols in Molecular Biology, John Wiley & Sons, N.Y. (1989). An example of low severity conditions is 4-6x SSC / 0.1-0.5% p / v SDS at 37-45 ° C for 2-3 hours. Depending on the source and concentration of the nucleic acid involved in the hybridization, alternative conditions of severity may be employed such as conditions of medium severity. Examples of medium severity conditions include l-4x SSC / 0.25% w / v SDS a > 45 ° C for 2-3 hours. An example of high severity conditions include 0.1-lx SSC / 0.1% w / v SDS at 60 ° C for 1-3 hours. The skilled person is aware of several parameters which can be altered during hybridization and washing and which will maintain or change either the conditions of severity. For example, another condition of severe hybridization is 4x hybridization of SSC at 65 ° C, followed by a wash at 0. lx SSC, at 65 ° C for about one hour. An alternative example of severe hybridization conditions is in 50% formamide, 4 x SSC at 42 ° C. Yet another example of severe conditions includes hybridization at 62 ° C in 6x SSC, 0.05x BLOTTO and washing at 2x SSC, 0.1% w / v SDS at 62 ° C. The methods according to the present invention can also be practiced using a splicing variant of a nucleic acid sequence encoding a NAP1-like protein. The term "alternative splice variant" as used herein encompasses variants of a nucleic acid sequence in which the selected introns and / or exons have been deleted, replaced or added. Such variants will be those in which the biological activity of the protein remains unaffected, which can be achieved by selectively retaining functional segments of the protein. Such splice variants can be found in nature or can be manufactured. Methods for making such splice variants are well known in the art. Therefore according to another aspect of the present invention, there is provided a method for improving the growth characteristics of plants, which comprises modulating the expression in a plant of an alternative splice variant of a nucleic acid sequence encoding a protein similar to NAP1 and / or modulating the activity and / or levels of the NAP1-like protein encoded by the alternative splice variant. Preferably, the splice variant is a splice variant of the sequence represented by the SEC. FROM IDENT. NO .: 1. Preferably, improved growth characteristics are increased yield, more preferably increased seed yield, more preferably increased seed yield comprises the increased rate of harvest, the increased number of full seeds and / or the total weight of seeds increased. Advantageously, the methods according to the present invention can also be practiced using allelic variants of a nucleic acid sequence encoding a NAP1-like protein, preferably an allelic variant of a sequence represented by SEQ. FROM IDENT. NO .: 1. Allelic variants exist in nature and are encompassed within the methods of the present invention in the use of these natural alleles. Allelic variants include Single Nucleotide Polymorphisms (SNPs), as well as Small Insertion / Elimination Polymorphisms (INDELs). The size of INDEL is usually less than 100 bp. SNPs and INDELs form the largest NAP1 class of sequence variants in polymorphic strains that occur naturally in most organisms. These are useful for, mapping genes and the discovery of genes and genetic functions. These are also useful for the identification of the gene locus, for example, plant genes, involved in determining the processes such as the growth rate, the size of the plant and the yield of the plant, the vigor of the plant, the resistance to diseases, tolerance to stress, etc. The activity of a NAP1-like protein or a homol thereof can also be modulated (increased or decreased) by introducing a genetic modality (preferably at the site of a gene similar to NAP1). The site of a gene as defined herein is understood to mean the coding region. The term "genetic modification" refers to a change by human intervention in the genetic content of a cell compared to a wild-type cell and includes techniques such as genetic engineering, reproduction or mutagenesis. The change in the genetic content includes modifications of the genome and includes the addition, elimination and substitution of the genetic material in the chromosomes of a plant cell as well as in episomes. The term also encompasses the addition of extrachromosomal information from a plant cell. Preferably, the genetic modification results in the modified expression of a NAP1-like nucleic acid, more preferably in the increased expression of a NAP1-like nucleic acid. The genetic modification can be introduced, for example, by any (or more) of the following methods: activation of T DA, TILLI-G, site-directed mutagenesis, homologous recombination or introducing and expressing in a plant cell a nucleic acid which encodes a protein similar to? AP1 or a homol thereof. After the introduction of the genetic modification, a step is followed to select a modulated activity of a protein similar to? AP1. Preferably, the modulated activity of a protein similar to? AP1 is the increased activity, whose increase in activity gives plants having improved growth characteristics such as increased seed yield. The selection step can be based on verifying the presence or absence of improved growth characteristics, or on verifying the presence or absence of selectable or detectable marker genes linked to a nucleic acid of interest introduced. T-DNA activation labeling (Hayashi et al., Science (1992) 1350-1353) involves the insertion of T-DNA usually containing a promoter (may also be a translation enhancer or an intron), in the genomic region of the T-DNA. interest gene of 10KB on or below the current of the coding region of a gene in a configuration such that the promoter directs the expression of the target gene. Normally, the regulation of the expression of the target gene by its natural promoter is interrupted and the gene falls under the control of the newly introduced promoter. The promoter is normally inserted into a T-DNA. This T-DNA is normally inserted into the genome of the plant, for example, through infection by Acr? acteriui ?. and leads to overexpression of genes near the inserted T-DNA. The resulting transgenic plants show dominant phenotypes due to overexpression of genes near the introduced promoter. The promoter that reintroduces can be any promoter capable of directing the expression of a gene in the desired organism, in this case a plant. For example, cell-preferred, inducible, tissue-preferred, constitutive and inducible promoters are suitable for use in T-DNA activation. A genetic modification can also be introduced into the site of a gene similar to NAP1 using the TILING technique (Genomes IN of Induced Local Lesions Objective). This is a mutagenesis technology useful to generate and / or identify and to eventually isolate mutagenized variants of a NAP1-like nucleic acid encoding a polypeptide capable of exhibiting NAP1-like activity. TILLING also allows the selection of plants that carry such mutant variants. These mutant variants may even exhibit activity similar to NAP1 higher than that exhibited by the gene in its natural form. TILLING combines high density mutagenesis with high yield selection methods. The stages normally followed in TILLING are: (a) mutagenesis of EMS (Redei and Koncz, 1992; Feldmann et al., 194; Ligtner and Caspar, 1998); (b) DNA preparation and grouping of individuals; (c) PCR amplification of a region of interest; (d) denaturation and annealing to allow heteroduplex formation; (e) DHPLC, where the presence of heteroduplex in a group is detected as an extra peak in the chromatogram; (f) identification of the mutant individual; and (g) sequencing the mutant PCR product. Methods for TILLING are well known in the art (McCallum Nat Biotechnol, 2000 Apr; 18 (4): 455-7, reviewed by Stemple 2004 (TILLING-a high-throughput harvest for functional genomics, Nat Rev Genet, 2004 Feb; 5 (2): 145-50)). Site-directed mutagenesis can be used to generate NAP1-like nucleic acid variants or portions thereof. Several methods are available to achieve site-directed mutagenesis, the most common being PCR-based methods (current molecular biology protocols, Wiley Eds. Http: //www.4ulr.com/products/currentprocotols/index.html). The activation of ADNT, TILLING and site-directed mutagenesis are examples of technologies that allow the generation of novel alleles and variants similar to NAPl. Homologous recombination allows the introduction into a genome of a selected nucleic acid at a defined selected position. Homologous recombination is a standard technology used routinely in biological sciences for lower organisms such as yeast or Physcomitrella moss. Methods to create homologous recombination in plants have been described not only for model plants (Offringa et al., Extrachromosomal homologous recombination and gene targeting in plant cells after Agrobacterium-mediated transformation, 1990 EMBO J. 1990 Oct; 9 (10): 3077-84), but also for forage plants, for example rice (Terada R, Urawa H, Inagaki Y, Tsugane K, lida S. Efficient gene targeting by omologus recombination in rice, Nat Biotechnol, 2002. lida and Terada. of two integrations, transgene and T-DNA, gene targeting by homologous recombination in rice, Curr Opin Biotechnol, 2004 Apr; 15 (2): 132-8). The targeting nucleic acid (which may be a NAP1-like nucleic acid or variant thereof as defined above) does not need to be directed to the site of a NAP1-like gene, but may be introduced into, for example, high expression regions. The targeting nucleic acid can be an improved allele used to replace the endogenous gene or it can also be introduced into the endogenous gene. The NAP1-like proteins have a typical domain organization, consisting of a NAP domain followed by an acidic C-terminal region. Therefore, it is visualized that the design of the domains of the NAP1-like protein in such a way that the activity of the NAP1-like protein is retained or modified, is useful to create the methods of the invention. A preferred type of variants include those generated by domain deletion, stacking or splicing of DNA (see for example He et al., Science 288, 2360-2363, 2000; or North American patents 5,811,238 and 6,395,547), provided that the protein similar to NAP1 resulting comprises a NAP domain and an acidic C-terminal region of 20 to 25 amino acids comprising at least 13 glutamic acid and / or aspartic acid residues. Directed evolution can also be used to generate nucleic acid variants that encode a NAP1-like protein. This consists of iterations of DNA rearrangement followed by selection and / or appropriate choice to generate NAP1-like nucleic acid variants or portions thereof encoding NAP1-like polypeptides or homologs thereof having a modified biological activity (Castle et al. al., (2004) Science 30 (5674): 1151-4; US Patents 5,811,238 and 6,395,547). Accordingly, as another aspect of the invention, a method is provided for improving the growth and development of plants when compared to corresponding wild type plants., preferably to increase the yield of plants, more preferably by increasing the seed yield of a plant, which comprises modulating the expression, preferably increasing the expression in a plant of a nucleic acid sequence encoding a NAP1-like protein and / or by modulating the activity and / or levels in a plant of a NAP1-like protein, preferably by increasing the activity and / or levels of a NAP1-like protein, wherein the nucleic acid sequence and the proteins include selected variants from: (i) a nucleic acid encoding a NAP1-like protein, wherein the NAP1-like protein is preferably as represented by SEQ. FROM IDENT. DO NOT. : l or encodes a protein similar to NAP1 as represented by SEC. FROM IDENT. DO NOT . : 2; (ii) an alternative splicing variant of a nucleic acid sequence encoding a NAP1-like protein or wherein the NAP1-like protein is encoded by a splicing variant; (iii) an allelic variant of a nucleic acid sequence encoding a NAP1-like protein or wherein the NAP1-like protein is encoded by an allelic variant; (iv) a sequence capable of hybridizing to a coding nucleic acid similar to NAP1, preferably under severe conditions; (v) a protein similar to NAP1 (vi) a protein similar to NAP1 as represented by SEQ. FROM IDENT. DO NOT . : 2 (vii) homologs and derivatives of a NAP1-like protein, preferably of the NAP1-like protein filed in SEC. FROM IDENT. NO .: 2, and wherein such NAPl-like protein comprises a NAP domain and acidic C-terminal, and has an activity that inhibits PP2a phosphatase ..

Preferably, the increased seed yield comprises one or more increased harvest rates, increased number of filled seeds and / or the total increased weight of seeds. In the methods of the present invention the modulated expression, and in particular the particular increased expression of the nucleic acid is visualized. Modulating expression (increasing or decreasing the expression) of a nucleic acid encoding a NAP1-like protein or modulating activity and / or NAP1-like protein levels encompasses altered expression of a gene and / or activity altered and / or the levels of a genetic product, ie a polypeptide, in specific cells or tissues. The altered (increased or decreased) expression of a gene and / or altered activity (increased or decreased) and / or the levels of a genetic product can be effected, for example by chemical means and / or recombinant means. The expression of modulation of a gene and / or the levels of a gene product and / or the modulation activity of a gene product can be effected directly through the modulation of expression of a coding gene similar to NAP1 and / or directly to through the modulation of activity and / or protein levels similar to NAPl. The modulated expression can result from the altered expression levels of a gene similar to endogenous NAP1 and / or - it can result from the modulated expression of a nucleic acid encoding NAP1 similar to that previously introduced into a plant. Similarly, the modulated levels and / or the activity of a NAP1-like protein can result from altered expression levels of an endogenous NAP1-like gene and / or can result from the altered expression of a similar coding nucleic acid to NAP1 that is previously introduced into a plant. Additionally or alternatively, the modulation of expression as mentioned above is carried out in an indirect mode, for example it can be performed as a result of decreased or increased levels and / or the activity of factors that control the expression of a gene similar to NAP1 or that they influence the activity and / or protein levels similar to NAPl. According to a preferred embodiment of the present invention, the expression modulation of a nucleic acid encoding a NAP1-like protein and / or the modulation of activity and / or levels of the NAP1-like protein itself is effected by recombinant means. Such recombinant means may comprise a direct and / or indirect approach for modulating the expression of a nucleic acid and / or for modulating the activity and / or levels of a protein. A direct and preferred approach for modulating the expression of a NAP1-like gene or modulating the activity and / or levels of a NAP1-like protein comprises introducing into an individual plant an isolated nucleic acid sequence encoding a NAP1-like protein. or a homologue, derivative or active fragment thereof. The nucleic acid can be introduced into a plant for example, by transformation. Therefore, according to a preferred aspect of the present invention, a method is provided for improving the growth and development of a plant, in particular to increase the yield of a plant comprising a genetic modification of the plant, whose modification Genetics comprises introducing a coding nucleic acid similar to NAP1 within a plant. Preferably, the increased yield of the plant is the increased yield of seeds, more preferably it comprises one or more increased harvest rates, the increased number of filled seeds or the increased total weight of seeds. According to a preferred aspect of the present invention, an increased or increased expression of a nucleic acid is visualized. Methods for obtaining improved or increased expression of genes or gene products are well documented in the art and include, for example, overexpression driven by a suitable promoter (preferably strong), the use of transcription enhancers or translation enhancers. The term "overexpression" as used herein means any form of expression that is in addition to the level of expression of wild-type original. Preferably, the nucleic acid that is introduced into the plant and / or the nucleic acid to be overexpressed in the plants is in the directed direction or with respect to the promoter to which it is operably linked. Preferably, the nucleic acid that is overexpressed encodes a NAP1-like protein, in addition preferably the nucleic acid sequence encoding the NAP1-like protein is isolated from a dicotyledonous plant, preferably of the Brassicaceae family, of In addition, the sequence is isolated from Arabidopsis thaliana, more preferably the nucleic acid sequence is as represented by SEQ. FROM IDENT. DO NOT. : 1, or a portion thereof, or encodes an amino acid sequence as represented by the SEC. FROM IDENT. DO NOT. : 2, or a homologue, derivative or active fragment thereof. Alternatively, the nucleic acid sequence encoding the NAP1-like protein is as depicted in SEQ. FROM IDENT. DO NOT. : 20 (GenBank accession number NM_101738) or is a portion thereof, or encodes an amino acid sequence as represented by SEC. FROM IDENT. DO NOT. : 21 (GenBank Accession Number NP_564063) or encodes a homologue, derivative or fragment thereof. It should be noted that the applicability of the invention does not depend on the use of the nucleic acid represented by the SEC. FROM IDENT. DO NOT. : 1, nor of the nucleic acid sequence encoding homologs, derivatives or active fragments of SEC. FROM IDENT. NO .: 2, or portions of the SEC. FROM IDENT. DO NOT . : 1, or sequences that hybridize with the SEC. FROM IDENT. DO NOT. : 1, can be used in the methods of the present invention. In particular, homologs from other species such as tobacco (SEQ ID NO: 7 or 9), corn (SEQ ID NO: 13 or 19), Medicago sativa (SEQ ID. NO .: 11), tomato (SEQ ID NO: 23) or rice (SEQ ID NO: 15 or 17) are also useful in the methods of the present invention. The present invention relates to methods for improving plant growth characteristics or methods for producing plants with improved growth characteristics, wherein the growth characteristics include increased yield, which comprises any one or more of: the increased number of shoots, number increased of the first panicles (the panicle being the highest and all the panicles that overlap with the highest panicle when it is aligned vertically), the increased number of second panicles, the total number of seeds increased, the number of seeds increased, the weight total increment of the emulas per plant, the increased harvest index, the weight in thousand of grain increased. The present invention also provides methods for improving one or more of the mentioned growth characteristics, without causing a penalty on one of the other growth characteristics, for example, the increase in the number of filled seeds while retaining the same number of spikelets per panicle. The term "increased yield" encompasses an increase in biomass in one or more parts of a plant relative to the corresponding parts or parts of wild-type plants. The term covers an increase in seed yield, which includes an increase in seed biomass (seed weight) and / or an increase in the number of (full) seeds and / or seed size and / or an increase in seed volume, each in relation to the corresponding wild-type plants. Depending on the crop, the parts of the plant in question may be previous terrestrial biomass (for example, corn, when used as silage, sugar cane), roots (for example, sugar beet), fruit (for example tomato), cotton fibers, or any other part of the plant which is of economic value. Taking the root as an example, an increase in yield can be manifested by an increase in one or more of the following: number of panicles per plant, number of spikelets per panicle, number of flowers per panicle, increase in the fill index of the seed, increase in the weight in a thousand of the grain, among others. For maize, the increase in seed yield can be reflected in, for example, an increase in rows (of seeds) per breakwater and / or an increased number of grains per furrow. An increase in the size and / or volume of the seed can also influence the composition of the seeds. An increase in the yield of the seed could be due to an increase in the number or size of the flowers. An increase in yield could also increase the harvest index, which is expressed as a ratio of the yield of harvestable parts, such as seeds, to total biomass.; or the weight in a thousand of the grain. The increased yield also covers the capacity for higher density planting (number of plants per hectare or acre). The equally modified cell division can contribute to increased performance. The term "modified cell division" encompasses an increase or decrease in cell division or an abnormal cell division / cytokinesis, altered plane of division, altered cell polarity, altered cell differentiation. The term also encompasses phenomena such as endocytosis, acytokinesis, polyploid, polybenia and endoreduplication. It can be seen that plants that have increased yield also exhibit a modified growth index when compared to corresponding wild-type plants. The term "modified growth index" as used herein includes, but is not limited to, a faster rate of growth in one or more parts of a plant (including seeds), in one or more stages in the cycle of growth. life of a plant. Plants with improved growth may show modified growth and may have modified values for their Tmid or T90 (respectively the time needed to reach half of their maximum size or 90% of their maximum size, each in relation to the plants of type corresponding wild). The term "improved growth" encompasses improved vigor, early blooming, modified cycle time. According to a preferred feature of the present invention, the yield of the methods according to the present invention results in plants having increased yield, in particular plants that have increased seed yield. Preferably, the increased seed yield includes at least one increase in any one or more of a number of filled seeds, the total weight of seeds, and the harvest index, each in relation to control plants. Therefore, according to the present invention, there is provided a method for increasing the yield of plants, which method comprises modulating the expression of a nucleic acid sequence encoding a NAP1-like protein and / or modulating the activity of the protein. similar to NAP1 itself in a plant, preferably wherein the NAP1-like protein is encoded by a nucleic acid sequence represented by SEC. FROM IDENT. DO NOT. : 1, or a portion thereof or by sequences capable of hybridizing thereto or wherein the NAP1-like protein is represented by SEC. FROM IDENT. DO NOT. : 2 or is a homologue, derivative or active fragment thereof. Alternatively, the NAP1-like protein can be encoded by nucleic acid sequences as depicted in SEQ. FROM IDENT. DO NOT. : 20 (GenBank Accession Number NM_101738), SEC. FROM IDENT. NO: 6, 8, 10, 12, 14, 16, 18 or 22 or by a portion thereof or by sequences capable of hybridizing with the same or the NAP1-like protein may be as represented in SEQ. FROM IDENT. DO NOT. : 21 (GenBank Accession Number NP_564063), SEC. FROM IDENT. NO .: 7, 9, 11, 13, 15, 17, 19, 23 or it can be a homologue, derivative or active fragment of any of them. The methods of the present invention are favorable for applying forage plants because the methods of the present invention are used to increase one or more of the total weight of seeds, the number of filled seeds and the harvest index of a plant. Therefore, the methods of the present invention are particularly useful for forage plants grown for their seeds, such as cereals, sunflower, soy, pea, flax, lupine, cañola. Accordingly, a particular embodiment of the present invention relates to a method of increasing seed yield (the increased total weight of seeds, the increased number of filled seeds and / or the increased rate of harvest) of a cereal. According to a further embodiment of the present invention, genetic constructs and vectors facilitating the introduction and / or expression of the nucleotide sequences useful in the methods according to the invention are provided. Therefore, according to the second embodiment of the present invention, there is provided a genetic construct for expression in a plant, comprising: (i) a nucleic acid sequence encoding a protein similar to NAP1; (ii) one or more control sequences capable of driving the expression in a plant of the nucleic acid sequence of (i); and optionally (iii) a transcription termination sequence. Constructs useful in the methods according to the present invention can be created using recombinant DNA technology well known to persons skilled in the art. Genetic constructs can be inserted into vectors, which can be commercially available, suitable for transformation within plants and suitable for expression of the gene of interest in the transformed cells. The genetic construct can be an expression vector wherein the nucleic acid sequence is operably linked to one or more control sequences that allow expression in prokaryotic and / or eukaryotic host cells. According to a preferred embodiment of the invention, the genetic construct is an expression vector designed to over-express the nucleic acid sequence. The nucleic acid sequence capable of modulating the expression of a nucleic acid encoding a NAP1-like protein and / or the NAP1-like protein itself can be a nucleic acid sequence encoding a NAP1-like protein or a homologue, derivative or active fragment thereof, such as any of the nucleic acid sequences described above. A preferred nucleic acid sequence is the sequence represented by SEQ. FROM IDENT. DO NOT. : l or a portion thereof or sequences capable of hybridizing thereto or a nucleic acid sequence encoding a protein represented by SEQ. OF IDEN. NO .: 2 or a homologue, derivative or active fragment thereof. Preferably, this nucleic acid is cloned in directed orientation relative to the control sequence to which it is operably linked. The plants are transformed with a vector comprising the sequence of interest (i.e., the nucleic acid sequence capable of modulating the expression of nucleic acid encoding a NAP1-like protein), which is operably linked to one or more control sequences (at least one promoter). The terms "regulatory element", "control sequence" and "promoter" are used interchangeably herein and are included in a broad context that refer to regulatory nucleic acid sequences capable of effecting expression of the sequences to which they are linked. Encompassed by the aforementioned terms are transcriptional regulatory sequences derived from a classical eukaryotic genomic gene (including the TTA block which is required for exact transcription initiation, with or without a CCAAT block sequence) and additional regulatory elements (eg. say, upstream activation sequences, enhancers and silencers) which alter gene expression in response to development and / or external stimulus, or in a specific manner of weaving. Also included within the term is a transcriptional regulatory sequence of a classical prokaryotic gene, in which case it may include a sequence of 35 blocks and / or 10-box transcriptional regulatory sequences. The term "regulatory element" also encompasses a synthetic fusion molecule or derivative which confers, activates or enhances the expression of a nucleic acid molecule in a cell, tissue or organ. The term "operably linked" as used herein refers to a functional linkage between the promoter sequence of the gene of interest, such that the promoter sequence is capable of initiating transcription of the gene of interest. Advantageously, any type of promoter can be used to drive the expression of the nucleic acid sequence that depends on the desired result. Preferably, the nucleic acid sequence encoding a NAP1-like protein is operably linked to a constitutive promoter. The term "constitutive" as defined herein refers to a promoter that is predominantly expressed in at least one tissue or organ and predominantly at any stage of plant life. Preferably, the promoter is expressed predominantly throughout the plant. Preferably, the constitutive promoter is the rice GOS2 promoter, or a similar resistance promoter and / or a promoter with a similar expression pattern. Alternatively, tissue-specific promoters may be used. For example, in cases where seed increase performance is visualized, the use of preferred seed, preferred flower, preferred promoters of active meristems or promoters in dividing cells can be contemplated. The promoter resistance and / or the expression pattern can be analyzed, for example, by coupling the promoter to a reporter gene and evaluating the expression of the reporter gene in various tissues of the plant. A suitable reporter gene well known to a person skilled in the art is beta-glucuronidase. Examples of alternative promoters with their respective expression patterns are presented in Table 2, and these promoters or derivatives thereof may be useful for the methods of the present invention.

Table 2: Examples of promoters for use in the performance of the present invention Arabidopsis cyclAt Cells by Shaul et al. 1996 Proc. (= cyc Bl; l) and cyc3aAt division / tej gone Nati. Acad. Sci. Ü.S.A. (type A) meristematic 93, 4868-4872 Promoter cell of Regad et al. 1995 Mol. arabidopsis tefl division / weave Gen. Genet. 248, 703-711 meristematic Catharanthus roseus Cells of Ito et al. 1994 Plant cyc07 division / tej gone Mol. Biol. 24, 863-87? meristematic Optionally, one or more terminator sequences can also be used in the construction introduced into a plant. The term "terminator" encompasses a control sequence which is a DNA sequence at the end of a transcriptional unit whose 3 'signal processing and polyadenylation of a transcription and primary transcription termination. Additional regulatory elements may include transcriptional as well as translational enhancers. Those skilled in the art are aware of the terminator and enhancer sequences which may be suitable for use in carrying out the invention. Such sequences would be known or easily obtained by a person skilled in the art. The genetic constructs of the invention may further include a replication sequence origin which is required for maintenance and / or replication in a specific cell type. An example is when a genetic construct is required to remain in a bacterial cell as an episomal genetic element (e.g., plasmid or cosmid molecule). Preferred origins of replication include, but are not limited to fl-ori and coIEl. The genetic construct may optionally comprise a selectable marker gene. As used herein, the term "selectable marker gene" includes any gene which confers a phenotype on a cell in which it is expressed to facilitate the identification and / or selection of cells which are transfected or transformed with a construct of nucleic acid of the invention. Suitable markers can be selected from markers that confer resistance to antibiotics or herbicides, which introduce a new metabolic trait or allow visual selection. Examples of selectable marker genes include genes that confer resistance to antibiotics (such as nptll which phosphorylates neomycin and kanamycin, or hpt, phosphorylating hygromycin), to herbicides (for example, bar that provides resistance to Basta, aroA or gox providing resistance against glyphosate), or genes that provide a metabolic trait (such as manA that allows plants to utilize maas as a single carbon source). Visual marker genes result in color formation (e.g., β-glucuronidase, GUS), luminescence (such as luciferase) or fluorescence (Green Fluorescent Protein, GFP and derivatives thereof). In a preferred embodiment, the genetic construct as mentioned above, comprises a gene similar to NAP1 in directed orientation coupled to a promoter that is preferably a constitutive promoter, such as the rice G0S2 promoter. Therefore, another aspect of the present invention is a vector construct that carries an expression cassette essentially similar to SEC. FROM IDENT. NO .: 3, comprising the rice G0S2 promoter, the NAP1-like gene from Arabidopsis and the transcription terminator sequence deltaza T-zein + T-rubisco. A sequence essentially similar to SEC. FROM IDE? T. ? O .: 3 encompasses a nucleic acid encoding a protein homologue to the SEC. FROM IDE? T. ?OR. : 2 or hybridizes to the SEC. FROM IDE? T. ?OR. : 1, whose nucleic acid is operably linked to a rice GOS2 promoter or a promoter with a similar expression pattern and / or whose nucleic acid binds to a transcription termination sequence. Therefore, according to another aspect of the invention, there is provided a genetic construct, comprising an expression cassette in which is located a nucleic acid sequence encoding a protein similar to α AP1, chosen from the group that comprises: (i) a nucleic acid sequence represented by SEQ. FROM IDE? T. ?OR. : 1 or the complement thread of it; (ii) a nucleic acid sequence encoding an amino acid sequence represented by SEQ. FROM IDENT. NO .: 2 or homologs, derivatives or active fragments thereof; (iii) a nucleic acid sequence capable of hybridising (preferably under severe conditions) with a nucleic acid sequence of (i) or (ii) above, the hybridization sequence of which preferably encodes a protein having similar protein activity to NAP1; (iv) a nucleic acid sequence according to (i) to (iii) above which degenerates as a result of the genetic code; (v) nucleic acid sequence which is an allelic variant to the nucleic acid sequences according to (i) to (iii); (vi) nucleic acid sequence which is an alternative splice variant to the nucleic acid sequences according to (i) to (iii); The present invention also encompasses plants obtainable by the methods according to the present invention. The present invention therefore provides plants obtainable by the methods of the present invention, which plants have increased yield and whose plants have modulated NAP1-like activity and / or protein levels and / or modulated expression of a nucleic acid encoding a protein. similar to NAPl. Preferably, the plants are transgenic plants comprising an isolated nucleic acid sequence encoding a NAP1-like protein, characterized in that the transgenic plant has been selected to have increased yield. Preferably further, the transgenic plant has been selected for modulated expression of a nucleic acid encoding a NAP1-like protein. In addition, preferably, the transgenic plant has been selected for modulated expression of a nucleic acid encoding a NAP1-like protein as represented by SEQ. FROM IDENT. NO.:2 According to a third embodiment of the present invention, there is provided a method for the production of transgenic plants having improved growth characteristics, comprising the introduction and expression in a plant of a nucleic acid encoding a NAP1-like protein as described above. Preferably, improved growth characteristics comprise increased yield, more preferably improved seed yield, more preferably comprising one or more of an increased number of filled seeds, increased harvest index or increased total seed weight. More specifically, the present invention provides a method for the production of transgenic plants that have increased yield, which method comprises: (i) introducing into a plant cell a nucleic acid sequence encoding a protein similar to NAP1 (ii) regenerating and / or cultivating a plant from a transgenic plant cell. The NAP1-like protein and / or the NAP1-like nucleic acid itself can be introduced directly into a plant cell or into the plant itself (including introduction into a tissue, organ or any other part of the plant). According to a preferred feature of the present invention, the nucleic acid is preferably introduced into a plant by transformation. The nucleic acid is preferably as represented by SEQ. FROM IDENT. DO NOT. : l or a portion thereof or sequences capable of hybridizing therewith, or is a nucleic acid encoding an amino acid sequence represented by SEQ. FROM IDENT. DO NOT. : 2 or a homologue, derivative or active fragment thereof. Alternatively, the nucleic acid sequence is as screened in SEC. FROM IDENT. NO .: 20 (GenBank Accession Number NM_101738), SEC. FROM IDENT. NO .: 6, 8, 10, 12, 14, 16, 18, 22 or a portion thereof or sequences capable of hybridizing with any of the aforementioned sequences. The amino acid sequence may alternatively be a sequence as depicted in SEQ. FROM IDENT. NO .: 21 (Access Number GenBank NP_564063), SEC. FROM IDENT. NO .: 7, 9, 11, 13, 15, 17, 19, 21 or homologs, derivatives or active fragments thereof. The term "transformation" as referred to herein encompasses the transfer of an exogenous polynucleotide within a host cell, irrespective of the method used for transfer. Plant tissue capable of subsequent clonal propagation, whether by organogenesis or embryogenesis, can be transformed with a genetic construct of the present invention and a whole plant regenerated therefrom. The particular tissue chosen will vary depending on the clonal propagation systems available for, and more in keeping with the particular species that are transformed. Exemplary tissue targets include leaf discs, pollen, embryos, cotyledons, hypocotyledons, megagametophytes, callus tissue, existing meristematic tissues (e.g., apical meristem, axillary buds, and root meristems), and induce meristem tissue (e.g., meristem of cotyledon and hypocotyledon meristeme). The polynucleotide can be introduced transiently or stably within a host cell and can be maintained non-integrated, for example, as a plasmid. Alternatively, it can be integrated into the host genome. The resulting transformed plant cell can then be used to regenerate a transformed plant in a manner known to persons skilled in the art. The transformation of a plant species is now a moderate routine technique. Advantageously, any of the methods of the various transformation methods can be used to introduce the gene of interest into a suitable ancestral cell. Transformation methods include the use of liposomes, electroporation, chemicals that increase the incorporation of free DNA, injection of DNA directly into the plant, particle barrel bombing, transformation using viruses or pollen, and microprojection. The methods can be selected from the calcium / polyethylene glycol method for protoplasts (Krens, F.A. et al., 1882, Nature 296, 72-74; Negrutiu I. et al., June 1987, Plant Mol. Biol. 8, 363-373); protoplast electroporation (Shillito R.D. et al., 1985 Bio / Technol 3, 1099-1102); microinjection within plant material (Crossway A. et al., 1985, Mol Gen Genet 202, 179-185); bombardment of particles coated with DNA or RNA (Klein T.M. et al., 1987, Nature 327, 70) infection with (non-integrative) virus and the like. Transgenic rice plants expressing a NAP1-like gene are preferably produced through Agrobacterium-mediated transformation using any of the well-known methods for rice transformation, such as those described in any of the following: European patent application EP 1198985 Al, Adelfita and Hodges (Planta, 199, 612-617, 1996); Chan et al. (Plant Mol. Biol. 22 (3) 491-506, 1993), Hiei et al. (Plant J. 6 (2) 271-282, 1994), whose descriptions are incorporated for reference herein as fully established. In the case of corn transformation, the preferred method is as described in Ishida et al. (Nat. Biotechnol, 1995 Jun; 14 (6): 745-50) or Frame et al. (Plant Physiol, 2002 May; 129 (1): 13-22), whose descriptions are incorporated herein by reference as fully established. Generally after transformation, the plant cells or cell clusters are selected for the presence of one or more markers which are encoded by expressible genes of plants co-transferred with the gene of interest, after the transformed material is regenerated within a complete plant. After DNA transfer and regeneration, putatively transformed plants can be evaluated, for example using Southern analysis, for the presence of the gene of interest, number of copies and / or genomic organization. Alternatively or additionally, the levels of expression of the newly introduced DNA can be monitored using Northern and / or Western analysis, both techniques being well known to persons having ordinary skill in the art. The transformed transformed plants can be propagated by a variety of means, such as by clonal propagation or classical breeding techniques. For example, a first generation (or TI) of transformed plant can by themselves give a second homozygous generation (or T2) of transformants, and T2 plants propagated in addition through classical breeding techniques. The transformed organisms generated can have a variety of forms. For example, these may be chimeras of transformed cells and untransformed cells; clonal transformants (e.g., all cells transformed to contain the expression cassette); grafts of transformed and untransformed tissues (for example, in plants, a transformed rhizome grafted to a non-transformed stem). The present invention clearly extends to any plant or plant cell produced by any of the methods described herein, and to all plant parts and propagules thereof. The present invention further extends to encompass the progeny of a transformed or transfected cell, tissue, organ or whole plant that has been produced by any of the aforementioned methods, the only requirement being that the progeny exhibit the same or same genotypic characteristics and / or phenotypic as those produced in the parent by the methods according to the invention. The invention also includes host cells that contain an isolated nucleic acid molecule encoding a protein capable of modulation levels and / or activity of a NAP1-like protein, preferably wherein the protein is a NAP1-like protein. The preferred host cells according to the invention are plant cells. Therefore, the invention also encompasses host cells or transgenic plants that have altered growth characteristics, characterized in that the host cell or transgenic plant has modulated the expression of a nucleic acid sequence encoding a NAP1-like protein and / or the modulated activity and / or protein level similar to NAPl. Preferably, altered growth characteristics comprise increased yield, more preferably increased seed yield. The invention also extends to harvestable parts of a plant such as, but not limited to, seeds, leaves, fruits, flowers, stems or stems, rhizomes, roots, tubers and bulbs. The invention also relates to products directly derived from a harvestable part of such a plant, such as dry granules or powders, oil, fat and fatty acids, starch or proteins. The term "plant" as used herein encompasses full plants, progenitors and progeny of the plants and parts of the plant, plant cells, tissues and organs.

The term "plant" also encompasses suspension cultures, embryos, meristematic regions, callus tissue, leaves, flowers, fruits, seeds, roots (including rhizomes and tubers), buds, bulbs, stems, gametophytes, sporophytes, pollen and microspores Plants that are particularly useful in the methods of the invention include algae, ferns and all plants belonging to the Viridiplantae superfamily, in particular monocotyledonous and dicotyledonous plants, including fodder or legumes for forage, ornamental plants, food crops, trees or shrubs selected from the list comprising Abelmoschus spp., Acer spp., Actinic / spp., Agropyron spp., Allium spp., Amaranthus spp., Ananas comosus, Annona spp. , Apium graveolens, Arabidopsis thaliana, Are chis spp, Artocarpus spp. , Asparagus officinalis, Avena sativa, Averrhoa carambola, Benincasa hispida, Bertholletia excelsea, Beta vulgaris, Brassica spp., Cadaba farinosa, Camellia sinensis, Canna indica, Capsicum spp., Carica papaya, Carissa macrocarpa, Carthamus tinctorius, Carya spp., Castanea spp., Cichorium endivia, Cinnamomum spp., Citrullus lana tus, Cit rus spp., Cocos spp., Cof fea spp., Cola spp., Colocasia esculents, Corylus spp., Crataegus spp., Cucumis spp., Cucurbit spp., Cynara spp., Daucus carota, Desmodium spp., Dimocarpus longan, Dioscorea spp., Diospyros spp., Echinochloa spp. , Eleusine coracana, Eriobotrya japonica, Eugenia uniflora, Fagopyrum spp. , Fagus spp. , Ficus carica, Fortunella spp., Fregaria spp., Ginkgo biloba, Glycine spp., Gossypium hirsutum, Helianthus spp., Hibiscus spp., Hordeum spp., Ipomoea batatas, Juglans spp., Lactuca sativa, Lathyrus spp., Lemna spp. ., Lens culinaris, Linum usitatissimum, Litchi chinensis, Lotus spp., Luffa acutangula, Lupinus spp., Macrotyloma spp., Malpighia emarginata, Malus spp., Maromea americana, Mangifera indica, Manihot spp. , Manilkara zapota, Medicago sativa, Melilotus spp., Mentha spp., Momordica spp., Monis nigra, Musa spp., Nicotiana spp., O / ea spp., Opuntia spp., Ornithopus spp., Oryza spp., Panicum miliaceum , Passiflora edulis, Pastinaca sativa, Persea spp., Petroselinum crispum, Phaseolus spp. , Phoenix spp. , Physalis spp., Pinus spp_, Pistada vera, Pisum spp., Poa spp., Populus spp., Prosopis spp., Prunus spp., Psidium spp_, Punic granatum, Pynis co munis, Quercus spp., Raphanus satívus, Rheum rhabarbarum , Ribes spp., Rubus spp., Saccharu spp., Sambucus spp., Sécale cereals, Sesamum spp., Solanum spp., Sorghum bicolor, Spinacia spp., Syzygium spp., Tamarindus indica, Theobroma cacao, Trifolium spp., Triticosecale rimpaui, Trificum spp., Vaccinum spp., Vida spp., Vigna spp., Vitis spp., Zea mays, Zizania palustris, Ziziphus spp., among others. According to a preferred feature of the present invention, the plant is a forage plant comprising soy, sunflower, canola, alfalfa, rapeseed or cotton. Further preferably, the plant according to the present invention is a monocotyledonous plant such as sugarcane, more preferably a cereal, such as rice, corn, wheat, millet, barley, oats, sorghum. The present invention also encompasses the use of nucleic acids encoding a NAP1-like protein, portions or variants thereof and the use of NAP1-like polypeptides, homologs or derivatives thereof. One use is related to improving the growth characteristics of plants, in particular to improve yield, especially seed yield. Seed yield may include one or more of the following: increased number of seeds, increased number of filled seeds, increased total weight of seeds, increased rate of crops, increased weight of one thousand grains, seed filling index, among others . Preferably, the NAP1-like protein or the nucleic acid encoding a NAP1-like protein is of plant origin, more preferably of a dicotyledonous plant, in addition to preference of the Brassicaceae family, more preferably, the NAP1-like protein is encoded by SEC. FROM IDENT. DO NOT. : 1 or is as represented by the SEC. FROM IDENT. NO .: 2. NAP1-like nucleic acids or variants thereof or NAP1-like polypeptides or homologs thereof may find use in breeding programs in which a DNA marker is identified which can be genetically linked to a gene similar to NAP1 or a variant thereof. The gene similar to NAP1 or variants thereof or NAP1-like protein or homologs thereof can be used to define a molecular marker. This DNA or protein marker can then be used in breeding programs to select plants that have improved growth characteristics. The gene similar to NAP1 or variant thereof may, for example, be a nucleic acid as represented by the SEC. FROM IDENT. DO NOT. : 1 or a nucleic acid encoding any of the aforementioned homologs. Allelic variants of a gene encoding a NAP1-like protein can also find use in marker assisted reproduction programs. Such reproduction programs sometimes require the introduction of allelic variation by mutagenic treatment of the plants, using for example, mutagenesis of EMS; alternatively, the program may start with a collection of allelic variants of "natural" origin so called involuntarily provoked. The identification of allelic variants then takes place, for example, by PCR. This is followed by a selection step for selection of higher allelic variants of the sequence in question and which result in improved growth characteristics in a plant, such as increased seed yield. The selection is usually carried out by verifying the monitoring performance of plants containing different allelic variants of the sequence in question, for example, different allelic variants of the SEC. FROM IDENT. DO NOT. : 1 or nucleic acids encoding any of the plant homologs mentioned above. The growth performance can be monitored in a greenhouse or in the field. In addition, optional stages include crossing plants, in which the higher allelic variant resulting in increased seed yield was identified, with another plant. This could be used, for example, to make a combination of interesting phenotypic traits. A nucleic acid similar to NAP1 or variant thereof can be used as probes to genetically and physically map the genes that are a part, and as markers for traits attached to those genes. Such information can be useful in the reproduction of plants in order to develop lines with the desired phenotypes. Such use of NAP1-like nucleic acids or variants thereof requires only a nucleic acid sequence of at least 10 nucleotides in length. NAP1-like nucleic acids or variants thereof can be used as restriction fragment length polymorphism (RFLP) markers. Southern blots of restriction-digested genomic plant DNA can be probed with the NAP1-like nucleic acids or variants thereof. The resulting grouping patterns can then be subjected to genetic analyzes using computer programs such as MapMaker (Lander et al. (1987) Genomics 1, 174-181) in order to construct a genetic map. In addition, nucleic acids can be used to probe Southern blots containing genomic DNAs treated by restriction endonuclease from a set of individuals representing the progenitor and the progeny of a defined genetic cross. Segregation of the DNA polymorphisms is observed and used to calculate the position of the nucleic acid similar to NAP1 or variant thereof in the genetic map previously obtained using this population (Botstein et al. (1980) Am. J. Hum. Genet .32, 314-331). The production and use of probes derived from plant genes for use in genetic mapping are described in Bematzky and Tanksley (Plant Mol. Biol. Repórter 4, 37-41, 1986). Numerous publications describe genetic mapping of specific cDNA clones using the methodology outlined above or variations thereof. For example, F2 inter-cross populations, hybridization populations, randomly matched populations, almost isogenic lines, and other sets of individuals can be used for mapping. Such methodologies are well known to those skilled in the art. Nucleic acid probes can also be used for physical mapping (ie, placement of sequences on physical maps, see Hoheisel et al., In: Nonmammalian Genomic Analysis: A Practical Guide, Academia press 1996, pp. 319-346, and references cited at the moment) . In another embodiment, the nucleic acid probes can be used in direct fluorescence mapping in situ hybridization (FISH) (Trask (1991) Genet Trains 7, 149-154). Although current methods of FISH mapping favor the use of large clones (several to several hundred kb, see Laan et al (1995) Genome Res. 5, 13-20), improvements in sensitivity may allow the performance of FISH mapping using shorter probes. A variety of methods based on nucleic acid amplification of genetic and physical mapping can be carried out using the nucleic acids. Examples include allele-specific amplification (Kazazian (1989) J. Lab. Clin. Med. 11, 95-96), fragment polymorphisms amplified with PCR (CAPS; Sheffield et al. (1993) genomics 16, 325-332), allele-specific ligation (Landegren et al (199) Science 241, 1077-1080), nucleotide extension reactions (Sokolov (1990) Nucleic Acid Res. 18, 3671), Radiation Irbid Mapping (Walter et al. (1997) Nat. Genet., 7.22-28) and Happy Mapping (Dear and Cook (1989) Nucleic Acid Res. 17, 6795-6807). For these methods, the sequence of a nucleic acid is used to design and produce primer pairs for use in the amplification reaction or primer extension reactions. The design of such primers is well known to those skilled in the art. In methods that employ PCR-based genetic mapping, it may be necessary to identify the DNA sequence differences between the progenitors of the mapping junction in the region corresponding to the nucleic acid sequence present. This, however, is not generally necessary to map methods. In this way, the generation, identification and / or isolation of modified plants with activity similar to NAP1 can be performed displaying improved growth characteristics. NAP1-like nucleic acids or variants thereof or NAP1-like polypeptides or homologs thereof may also find use as growth regulators. Since these molecules have been shown to be useful in improving the growth characteristics of plants, they would also be useful growth regulators, such as herbicides or growth stimulators. The present invention therefore provides a composition comprising a nucleic acid similar to NAP1 or a variant thereof or a NAP1-like polypeptide or homologue thereof, together with a suitable carrier, diluent or excipient, for use as a growth regulator, preferably as a growth promoter, more preferably for increase yield. The methods according to the present invention result in plants having improved growth characteristics, as described above. These advantageous growth characteristics can also be combined with other economically advantageous features, such as traits that improve the additional performance, tolerance to various stresses, traits that modify various architectural aspects and / or biochemical and / or physiological aspects. Accordingly, the methods of the present invention can also be used in so-called "genetic stacking" methods.

Description of figures The present invention will now be described with reference to the following figures in which: Figure 1. The phylogenetic tree representing the relationships between the NAP and SET proteins from yeast, men and plants. The tree is established by the AlignX program of VNTI Suite 5.5 (Informax, htt: // www. Informaxinc. Com /). The matrix used to generate the multiple alignment is Blosum62 and the alignment parameters used were: Gap Gap Penalty, 10 Gap Extension Penalty, 0.5; separation penalty range Gap, 8; % identity for alignment delay, 40. The phylogenetic tree is constructed using the Neighbor Union method of Saitou and Nei. The access numbers GenBank and MIPS (for Arabidopsis thaliana) of the sequences used in the alignment are indicated in the tree. In: Thaliana Arabipose, Gm: Glycine max, Nt: Nicotiana tabacum (sequences derived from WO 03/08515), Os: Oryza sativa, Ps: Pisu sativum, Zm: Zea mays, Hs: Homo sapiens, Se: Saccharomyces cerevisiae. Figure 2. Schematic presentation of the entry p68 clone, which contains CDS0406 within AttLl and Attl2 sites for Gateway® cloning in the pDONR201 structure. CDS0406 is the internal code for the coding sequence similar to NAP1 Arabadopsis. This vector also contains a bacterial kanamycin resistance cassette and a bacterial origin of replication. Figure 3. The binary vector for the expression in Oryza sativa of the NAP1-like gene of Arabidopsis (CDS0406) under the control of the Gos2 promoter (PRO0129). This vector contains a T-DNA derivative from the TI plasmid, limited by a left border (repeat LB, LB Ti C58) and a right border (repeat RB, RB Ti C58)). From the left border to the right border, this T-DNA contains: a cassette of antibiotic selection of transformed plants; a selectable marker cassette for visual selection of transformed plants and the dual terminator cassette PRO0129 -CDS0406-zein and rbcS-deltaGA for expression of the NAP1-like gene of Arabidopsis. This vector also contains an origin of replication of pBR322 for bacterial replication and a selectable marker (Spe / SmeR) for bacterial selection with spectinomycin and streptomycin. Figure 4 Medicago-like NAP1 protein was expressed in E. coli and purified from unpurified cell extract by affinity chromatography through the 6XHIs tag. The elution of the 38 kD protein at different concentrations of imidazole from the nickel-agarose resin is visualized by Western blot using anti-6xHIS antibody (Sigma, St. Louis, USA). Figure 5 Alignment of the NAP1-like protein of Arabidopsis thaliana (similar to AtNAPl) and the NAP1-like protein of Medicago sativa (similar to MsNAPl) using the Needleman and Wunsch algorithm. The opening gap penalty was determined at 10, the gap extension penalty was 0.5. With these parameters, the sequence identity was 71.2% and the sequence homology 84.5%.

Figure 6 The NAP1-like protein has a nuclear location in plants. A) Medicago's NAP1-like protein has been shown to be located in the nucleus of cultured alfalfa cells by indirect immunofluorescence using an elevated antibody against the purified protein (left photograph of panel A). To confirm the nuclear localization, the nucleus was stained in parallel with the fluorescent DAPI dye (right photograph of panel A). In the insert, the arrow points to a metaphase cell. A weak fluorescence indicates low abundance of the NAP1-like protein around the chromosomes in metaphase cells without a nuclear compartment. B) The transiently expressed Arabidopsis-like NAP1 protein, combined with GFP, is localized to the nucleus in Arabidopsis cells following a PEG-mediated incorporation of the genetic construct into protoplasts. Figure 7 Purified Medicago NAP1-like protein inhibits phospho-histone H2B dephosphorylation activity in vitro of PP2A (purified from rabbit skeletal muscle), but has no influence on the dephosphorylation of glycogen phosphorylase by the same enzyme. Figure 8 Examples of sequences useful for performing the methods according to the present invention.

Examples The present invention will now be described with reference to the following examples, which are by way of illustration only. Unless stated otherwise, recombinant DNA techniques are performed according to standard protocols described in (Sambrook (2001) Molecular Cloning: a laboratory manual, 3rd Edition Cold Spring Harbor Laboratory Press, CSH, New York) or in volumes 1 and 2 of Ausubel et al. (Current Protocols in Molecular Biology, New York: John Wiley and Sons, 1998). The standard materials and methods for molecular work of plants are described in Plant Molecular biology Labfase (1993) by R.D.D. Croy, published by BIOS Scientific Publications Ltd (UK) and Blackwell Scientific Publications (UK). Example 1: Genetic Cloning The NAP1 type of Arabidopsis was amplified (internal reference CD20406) by PCR using a seedling cDNA library of Arabidopsis thaliana as a template (Invitrogen, Paisley, UK). After reverse transcription of RNA extracted from seedlings, the cDNAs were cloned into pCMV Sport 6.0. The average insert size of the block was 1.5 kb, and the original number of clones was 1.59xl07 cfu. The original titer was determined to be 8.6xl05 cfu / ml, after the first amplification of dxlO11 cfu / ml. After plasmid extraction, 200 ng of the template was used in 50 μl of PCR mixture. The primers prml505 (SEQ ID NO: 4) and prml506 (SEQ ID NO: 5), which include the AttB sites for Gateway recombination, were used for PCR amplification. The PCR was transformed using Hifi tag DNA polymerase under standard conditions. A 771 bp PCR fragment was also amplified and purified using standard methods. The first stage of the Gateway procedure, the BP reaction, was then performed, during which the PCR fragment recombines in vivo with the pDONR201 plasmid to produce, according to the Gateway terminology, an "entry clone" p68 (Figure 2) . Plasmid pDONR201 was purchased from Invitrogen, as part of Gateway® technology.

Example 2: Construction of Vector The entry p68 clone was subsequently used in an LR reaction with p0640, a destination vector used for transformation of Oryza sativa. This vector contains as functional elements within the edges of T-DNA; a selectable plant marker, a visual marker expression cassette; and a Gateway cassette intended for in vivo recombination of LR with the sequence of interest already cloned in the entry clone. A GOS2 promoter for constitutive expression (PRO0129) is located upstream of this Gateway cassette. After the LR recombination step, the resulting expression vector p73 (Figure 3) can be transformed into strain Acjrrojacteríuzn LBA4404 and subsequently to Oryza sativa plants.

Example 3: Rice Transformation Mature dried seeds were dehusked from Nipponbare cultivar of Oryza sativa japonica. Sterilization was done by incubating the seeds for one minute in 70% ethanol, followed by 30 minutes in 0.2% HgCl2 and by 6 15 minute washes with sterile distilled water. The sterile seeds were then germinated in a medium containing 2,4-D (callus induction medium). After an incubation of 4 weeks in the dark, calluses derived from embryogenic scutellum were excised, and propagated in the same medium for another 2 weeks. 3 days before co-culture, the embryogenic callus pieces were subcultured in fresh medium to stimulate cell division activity. Strain LBA4404 from? Srrsjacfcerium harboring the binary p73 vector was used for co-culture. The Agrobacterium strain was cultured for 3 days at 27 ° C in AB medium with the appropriate antibiotics. The bacteria were then harvested and suspended in liquid co-culture medium at OD600 at approximately 1. The suspension was transferred to a petri dish and the calli were immersed in the suspension for 15 minutes. After, the callused tissues were dried on a filter paper, transferred to solidified co-culture medium and incubated for 3 days in the dark at 25 ° C. Subsequently, the co-cultivated callus was grown in medium containing 2,4-D for 4 weeks in the dark at 28 ° C in the presence of a selective agent at a suitable concentration. During this period, developed resistant callous islands were grown. In the transfer of this material to a medium of regeneration and incubation in the light, the embryogenic potential and the outbreaks developed in the following four to five weeks were released. The shoots were excised from the callus and incubated for 2 to 3 weeks in an auxin-containing medium from which they were transferred to the soil. Hardened shoots were grown under high humidity and short days in a greenhouse. Finally the seeds were harvested three to five months after the transplant. The method produced single-site transformants at an index of more than 50% (Aldemita and Hodges, Planta 199, 612-617, 1996; Chan et al., Plant Mol. Biol. 22 (3), 491-506, 1993; Hiei et al., Plant J. 6 (2), 271-282, 1994).

Example 4: Evaluation of Transformants: Measurements of vegetative growth Approximately 15 to 20 independent TO transformants were generated. The primary transformants were transferred from the tissue culture chambers to a greenhouse for the growth and harvest of IT seeds. Five cases were retained from which the IT progeny segregated 3: 1 for the presence / absence of the transgene. For each of these cases, 10 IT seedlings containing the transgene (hetero and homozygotes) and 10 IT seedlings lacking the transgene (nulizygotes) were selected by visual marker selection. The selected IT plants were transferred to a greenhouse. Each plant received a unique bar code mark to unambiguously join the phenotype data to the corresponding plant. The selected IT plants were grown in soil in 10 cm diameter pots under the following environmental parameters: photoperiod = 11.5 hours, daylight intensity = 30,000 lux or more, daytime temperature = 28 ° C or higher, night temperature = 22 ° C, relative humidity = 60-70%. The transgenic plants and the corresponding nullizygotes were grown parallel to the random positions. From the sowing stage to the maturity stage the plants were passed several times through an image scanning booth. At each point of time the digital images (2048x1536 pixels, 16 million colors) were taken from each floor by at least 6 different angles. The mature primary panicles were harvested, bagged, and labeled with a bar code and then dried for three days in the oven at 37 ° C. The panicles were then threshed and all the seeds were collected. The flat shells were separated from the empty ones using an air blowing device. After separation, both batches of seeds were then counted using a commercially available counting machine. The empty seeds were discarded. The filled seeds were weighed on an analytical scale and the cross-sectional area of the seeds was measured using image digitalization. This procedure resulted in the set of parameters related to seeds described later. These parameters were derived in an automated mode from the digital images using image analysis software and analyzed statistically. A double factor ANOVA (analysis of variance) corrected for the unbalanced design was used as a statistical model for the global evaluation of phenotypic characteristics of the plant. An F test was carried out on all the measured parameters of all plants of all cases transformed with that gene. The F test was carried out to verify an effect of the gene on all cases of transformation and to verify a total effect of the gene, also called "global genetic effect". If the value of the F test shows that the data is remarkable, then it is concluded that there is a "gene" effect, meaning that not only the presence in the position of the gene is causing the effect. The threshold of transcendence for a global genetic effect is established at 5% of the probability level for the F test. To verify an effect of the genes within a case, that is, for a specific effect of line, a test was performed f within each case using data established from the transgenic plants and the corresponding null plants. "Null plants" or "null segregants" or "nullizygotes" are the plants treated in the same way as the transgenic plant, but from which the transgene has been segregated. The null plants can also be described as the homozygous negative transformed plants. The threshold of transcendence for the test t is set at 10% of the probability level. The results for some cases may be above or below this threshold. This is based on the hypothesis that a gene could not only have an effect in certain positions in the genome, and that the appearance of this effect dependent on the position is not common. This kind of genetic effect is also called in the present a "gene line effect". The p-value is obtained by comparing the value t to the distribution t or alternatively, comparing the value F to the distribution F.

The p-value gives the probability that the null hypothesis (that is, there is no effect of the transgene) is correct. Vegetative growth and seed yield were measured according to the methods as described above. The inventors surprisingly find that the total weight of the seeds, the number of filled seeds and the harvest index were increased in the rice plants transformed with the gene similar to NAP1 when compared to the control plants without the gene similar to NAPl. The data obtained in the first experiment was confirmed in a second experiment with T2 plants. Four lines that had the correct expression pattern were selected for further analysis. The seed lots from positive plants (both hetero and homozygous) in IT were selected by monitoring the expression of the marker. For each selected case, the heterozygous seed lots were then retained for the T2 evaluation. Within each batch of seeds an equal number of positive and negative plants were grown in the greenhouse for evaluation. A total number of 160 transformed plants similar to NAP1 were evaluated in the T2 generation, which is 40 plants per case of which 20 positive for the transgene and 20 negative.

Example 5: Evaluation of transformants: measurement of seed-related parameters In the analysis of the seeds as described above, the inventors found that plants transformed with the genetic construct similar to NAP1 had a higher number of filled seeds, a total weight higher seed and an increased harvest index compared to plants lacking the transgene similar to NAPl. The positive results obtained by the plants in the TI generation were obtained again in the T2 generation. Not only the individual transgenic lines were classified significantly better than the corresponding nulizigote control lines, but there was also a significant positive total effect when all the plants of all T2 cases tested were evaluated, strongly indicating a global genetic effect. An overview of the data is given in Table 3.

Table 3 The% increase presents the average increase of all tested cases. The p-value represents the p-value derived from the F-test.

Number of filled seeds The number of filled seeds was determined by counting the number of filled husks that remained after the separation stage. 4 of the 5 test lines showed an increase in the number of filled seeds, rising up to 37%. There was a total increase of 17% in the number of filled seeds produced by transgenic plants relative to corresponding null segregants, whose increase is statistically significant (p-value 0.0352). In generation T2, there was an increase for all the test lines, variant between 14 and 46%. The average increase for the T2 lines was 28%, this average increase was also statistically significant (p-value of 0.0013). The combined analysis of TI and T2 data also confirmed that the overall genetic effect was highly remarkable (p-value of 0.0003).

Total seed yield The total seed yield (total weight of the seeds) per plant was measured by weighing all the filled husks harvested from a plant. All the transgenic IT lines showed an increase in the total weight of the seeds, which varied between 8 and 43%. On average, the increase in seed yield was 24% and this overall effect from the presence of the transgene in the seed yield was remarkable, as evidenced by a P value for the F test of 0.0076. These results were also observed in the T2 generation. The 4 test lines had an increase in production between 14 and 48% with an average of 28%. This average increase was statistically significant (p-value of 0.0013) and also the combined analysis of the TI and T2 plants showed that there was a global genetic effect (p-value of 0.0006).

Harvest index Harvest index in the present invention is defined as the ratio between the total yield of seeds and the previous land area (mm2) multiplied by a factor of 106. 4 of the 5 test lines showed an increase in the index of harvest, varying between 9 and 48%.

There was a remarkable global effect (an effect associated with the presence of the transgene) on the harvest index (a total increase of 15%), with a p statistically significant for the F test of 0.085. Similar results were obtained for T2 plants. The harvest index for individual lines increased between 12 and 34% with a significant average of 17% (p-value of 0.0025). Here, too, the combined analysis of the TI and T2 data showed a global genetic effect (p-value of 0.003). It is known to persons skilled in the art that the expression of transgenes in plants, and consequently also the phenotypic effect due to the expression of such a transgene, can be deferred between different transgenic lines independently obtained and the progeny thereof. The transgenes present in different transgenic plants independently obtained differ from each other by the chromosomal insertion site as well as by the number of transgenic copies inserted in that site and the configuration of those transgenic copies in that site. Differences in expression levels can be attributed to influence the chromosomal context of the transgene (the so-called position effect) or of silencing mechanisms driven by certain transgene configurations (for example, inward facing tandem transgene insertions are prone to mute at the transcriptional or post-transcriptional level). Notwithstanding these possible causes of variation, the data show that transgenic plants expressing the NAP1-like gene consistently give a higher number of filled seeds, a higher total weight of seeds, as well as an increased harvest index, each in relation to the corresponding non-transgenic plants. The observed increases were notable in both the TI and T2 generation, which is a strong argument for a global genetic effect as evidenced by the p-values of the combined analysis.

Example 6: Characterization of a NAP1-like protein of Medicago sativa: Materials and methods Isolation of the full-length cDNA clone of the putative alfalfa PP2A inhibitor An isolated cDNA fragment encoding a portion of a putative alfalfa-like protein NAP1 (Medicago sativa) has been used to isolate the full-length clone to from the phage cDNA library -ZAP of alfalfa root nodule (Savoure et al., Plant Mol. Biol. 27, 1059-1070) using standard selection procedures as described by the manufacturer (Stratagene). 400,000 plates were selected, 20 clones were retained, of which 18 were positive in the second hybridization selection. 8 of these clones were selected for additional work and were converted into phagemids from individual phages. Four clones were sequenced and two of these were shown to be full-length cDNA clones for the putative NAP1-like protein. One of the clones (MslO.l) was used for additional work (SEQ ID NO: 10, which encodes the protein of SEQ ID NO: 11).

Production and purification of Medicago NAP1-like protein The cDNA sequence encoding the NAP1-like protein of Medicago sativa was inserted into the Ncol / Xhol site of the pENTRY4 GATEWAY® vector (Invitrogen) and subsequently introduced into the vector of bacterial expression pDEST17. The vector pDEST17 allowed the expression of the NAP1-like protein in E. coli BL21 cells as a protein labeled 6xHIS. The 34 kDa NAP1-like protein was purified by affinity chromatography using a nickel agarose resin (Sigma) (Figure 4).

Phosphatase Activity Measurements The activity that inhibits the potential phosphatase of the Medicago sativa NAP1-like protein was tested in vitro on the catalytic subunits of purified Protein Phosphatase 2A (PP2A) from the rabbit skeletal muscle using glycogen phosphorylase labeled with 32 P -isotope and histone H2A proteins as substrates according to Ulloa et al. (1993).

Intracellular Localization of MsNAP1-Like and AtNAPl-Like Proteins Polyclonal anti-MsNAPl-like antibodies were raised in rabbits against the protein labeled 6xHIs using a standard immunization protocol. The protoplasts were isolated from alfalfa (Medicago sativa) cells cultured with suspension and fixed by 6% formaldehyde. The cells were then bound to glass plates coated with poly-L-lysine and exposed to anti-MsNAPI-like antiserum (200 x diluted in PBS), washed and exposed to goat anti-rabbit secondary antibody conjugated with FITC. (SIGMA, dilution lOOx). The nuclei were stained with DAPI (0.02 mg / ml) in parallel and photographed with a TE300 fluorescent microscope and a SPOT II color CCD camera. The coding region of the Arabidopsis thaliana ortholog of the NAP1-like protein of Medicago sativa (SEQ ID NO: 1) was inserted into the frame with the green fluorescent protein (GFP) within the compatible plant expression vector. GATEWAY® (pK7WGF2). The protoplasts were isolated and transfected with the plasmid DNA using standard procedures. Transient expression was recorded one or two days after transfection by fluorescence microscopy.

Results NAP1-like proteins of Arabidopsis and Medicago are located in the nucleus The NAP1-like protein of Medicago sativa was highly homologous to the NAP1-like protein of Arabidopsis: the sequence identity was 71.2% and the sequence similarity was 84.5% ( Figure 5). Using antibodies similar to anti-MsNAPl, indirect immunofluorescence revealed that the antibodies recognized a protein that was located in the nucleus of alpha cells cultured in suspension. This location was verified by the nuclear dye, DAPI. The faded fluorescence was associated with the chromosomes in metaphase cells (Figure 6a, insert). The NAP1-like protein of Arabidopsis labeled GFP was also located exclusively in the nucleus of Arabidopsis cells grown in suspension (Figure 6.B). 2) The alfalfa-like NAP1 protein inhibits PP2A phosphatase activity in vitro on a phosphate-histone substrate. The purified alfalfa-like NAP1 protein was added in various concentrations to reaction mixtures containing the catalytic subunits of skeletal muscle PP2A. of rabbit and phosphorylated H2a histone, or glycogen phosphorylase as a substrate. It was observed that the NAP1-like protein had no influence on the dephosphorylation of glycogen phosphorylase even at 500 mM concentration, but 2.5 M concentration of the NAP1-like protein efficiently inhibited the activity of PP2A on the phospho-histonH2A substrate ( 50% decrease in activity) (Figure 7).

Conclusion The NAP1-like proteins of Medicago sativa and Arabidopsis thaliana show structurally and functionally similarity. Plant NAP1-like proteins inhibit the activity of phosphates (PP2A) in vitro on histone substrates, indicating a possible in vivo role in the organization of chromatin and genetic transcription.

Claims (29)

1. CLAIMS 1. Method for improving growth characteristics of a plant relative to corresponding wild-type plants, which comprises introducing a genetic modification in the plant and selecting modulated expression in the plant of a nucleic acid sequence encoding a protein similar to NAPl .
2. 2. Method according to claim 1, wherein the modulated expression is the increased expression.
3. Method according to claim 1 or 2, wherein the genetic modification is effected by one of the site-directed mutagenesis, homologous recombination, TILLING, T-DNA activation and DNA rearrangement.
4. 4. Method according to claim 1 or 2, wherein the genetic modification comprises introducing an isolated nucleic acid sequence encoding a NAP1-like protein within a plant.
5. The method according to claim 4, wherein the nucleic acid is derived from a plant, preferably from a dicotyledonous plant, more preferably from the family Brassicaceae, more preferably from Arabidopsis thaliana.
6. 6 Method according to claim 4 or 5, wherein the nucleic acid sequence and the proteins include variants chosen from: (i) a nucleic acid encoding a NAP1-like protein, wherein the NAP1-like protein is preference as represented by the SEC. FROM IDENT. DO NOT. : l or encodes a protein similar to NAP1 as represented by SEC. FROM IDENT. DO NOT . : 2; (ii) an alternative splicing variant of a nucleic acid sequence encoding a NAP1-like protein or wherein the NAP1-like protein is encoded by a splicing variant; (iii) an allelic variant of a nucleic acid sequence encoding a NAP1-like protein or wherein the NAP1-like protein is encoded by an allelic variant; (iv) a sequence capable of hybridizing to a coding nucleic acid similar to NAP1, preferably under severe conditions; (v) a protein similar to NAP1; (vi) a protein similar to NAP1 as represented by SEC. FROM IDENT. DO NOT . : 2; (vii) homologs and derivatives of a NAP1-like protein, preferably of the NAP1-like protein presented in SEQ. FROM IDENT. DO NOT. : 2, and wherein such a NAP1-like protein comprises a NAP domain and an acidic C-terminus, and has activity that inhibits PP2a phosphatase.
7. 7. Method according to any of claims 1 to 6, wherein the improved growth characteristics is increased yield, preferably increased seed yield.
8. The method according to claim 7, wherein the increased yield of seeds comprises one or more increased number of filled seeds, increased total weight of seeds or the increased rate of Crop, each one relative to the corresponding wild-type plants. .
9. 9. Method according to any of claims 4 to 8, wherein the nucleic acid encoding a NAP1-like protein is operably linked to a constitutive promoter, preferably a GO 2 promoter.
10. 10. Method for the production of a plant transgenic that has increased yield, which method comprises: (i) introducing into a plant cell a nucleic acid sequence encoding a NAP1-like protein; (ii) regenerating and / or growing a plant from a transgenic plant cell.
11. 11. Plants with increased yield obtainable by a method according to any of claims 1 to 10, including harvestable parts, propagules, seeds or progeny thereof, and including products directly derived therefrom.
12. 12. The genetic construct for expression in a plant, comprising: (i) a nucleic acid sequence encoding a NAP1-like protein; (ii) one or more control sequences capable of driving the expression in a plant of the nucleic acid sequence of (i); and optionally (iii) a transcription termination sequence.
13. 13. The construct according to claim 12, wherein the nucleic acid encoding a NAP1-like protein is chosen from the group comprising: (i) a nucleic acid sequence represented by SEQ. FROM IDENT. DO NOT. : 1 or the complement thread of it; (ii) a nucleic acid sequence encoding an amino acid sequence represented by SEQ. FROM IDENT. • DO NOT. : 2 or homologs, derivatives or active fragments thereof; (iii) a nucleic acid sequence capable of hybridising (preferably under severe conditions) with a nucleic acid sequence of (i) or (ii) above, whose hybridization sequence preferably encodes a protein having similar protein activity to NAP1;
14. (iv) a nucleic acid sequence according to (i) to (iii) above which degenerates as a result of the genetic code; (v) nucleic acid sequence which is an allelic variant to the nucleic acid sequences according to (i) to (iii), - (vi) nucleic acid sequence which is an alternative splice variant to the sequences of nucleic acid according to (i) to (iii); and wherein the NAP1-like protein comprises a NAP domain and an acidic C-terminus and has activity that inhibits PP2a phosphatase. The construction according to claim 12 or 13, wherein the control sequences comprise at least one constitutive promoter, preferably a GOS2 promoter.
15. 15. The construct according to any of claims 12 to 14, wherein the nucleic acid sequence encoding a NAP1-like protein is oriented in the directed direction relative to the control sequence.
16. 16. The construction comprising an expression cassette essentially similar to SEC. FROM IDENT. NO .: 3.
17. 17. The transgenic plant comprising an isolated nucleic acid sequence encoding a NAP1-like protein, characterized in that the plant has been selected for having increased yield.
18. 18. The transgenic plant of claim 17, selected by increased expression of a nucleic acid encoding a protein similar to NAPl. The transgenic plant of claim 17 or 18, wherein the isolated nucleic acid encoding a NAP1-like protein encodes a protein as depicted in SEQ. FROM IDENT. NO .: 2. The transgenic plant according to any of claims 17 to 19, wherein the plant is a forage plant comprising soybean, sunflower, canola, alfalfa, rape seed or cotton, preferably the plant is a monocotyledonous plant such as sugarcane, more preferably a cereal, such as rice, corn, wheat, millet, barley, oats, sorghum. 21. The transgenic plant cells, transgenic plants or transgenic plant parts, including harvestable parts, propagules, seeds or transgenic progeny, and products directly derived therefrom, from a plant according to any of claims 17 to 20. 22 Use of a nucleic acid sequence encoding a NAP1-like protein, or a portion thereof or a sequence that hybridizes thereto, to increase the yield of a plant. 23. Use of a protein similar to NAP1, and / or homologs, derivatives or active fragments thereof to increase the yield of a plant. 24. Use of claim 22 or 23, wherein the increased yield is increased seed yield. 25. The use of claim 24, wherein the increased yield of seeds comprises one or more of the total weight of the seeds, number of filled seeds and harvest index. 26. Use of any of claims 22 to

    25, wherein the nucleic acid sequence encoding a NAP1-like protein or the NAP1-like protein itself is as depicted in SEQ. FROM IDENT. NO .: 1 or 2. 27. A composition for increasing the yield of a plant, comprising a protein similar to NAP1 and / or a nucleic acid encoding a protein similar to NAPl. 28. A composition for increasing the yield of plants comprising a protein represented by SEC. FROM IDENT. DO NOT . : 2 or a homologue, derivative or active fragment thereof. 29. A composition for increasing the yield of plants comprising a nucleic acid as represented by SEQ ID NO. : 1 or a portion thereof or a sequence that hybridizes thereto, or which encodes a protein as depicted in SEC.DELTA.NO. : 2.