CN105177002A - miR159a related to barley powdery mildew resistance and application thereof - Google Patents

Abstract

The invention provides an miR159a related to barley powdery mildew resistance and application thereof, belonging to the fields of gene engineering and crop molecular biology. The miR159a is derived from barley, the nucleotide sequence is disclosed as SEQ ID NO.1, the target gene is GAMYB, and the nucleotide sequence is disclosed as SEQ ID NO.3. The invention detects that the instantaneous overexpression in the barley epidermal cells can lower the powdery mildew resistance of the barley cells; and the expression of the GAMYB gene is subjected to reverse control of the miR159a, and the miR159a obtained by reversely controlling the GAMYB gene expression can forwardly control the powdery mildew resistance of barley. The miR159a related to barley powdery mildew resistance can be used in the fields of barley germplasm resource improvement and genetic breeding, can also be used for culturing powdery-mildew-resistant barley species, and thus, has favorable market application prospects.

Description

The miR159a relevant to barley mildew-resistance and application thereof

Technical field

The present invention relates to crop molecular biology and field of molecular breeding, more specifically, relate to the miR159a relevant to barley mildew-resistance and application thereof.

Background technology

Barley is one of staple food crop of extensively planting in the whole world, and its world's sown area is only second to wheat, paddy rice and corn, ranks the 4th.Barley can be cooked food, feed and beer brewing raw material, has important economic worth.Barley powdery mildew (barleypowderymildew) is one of main fungal disease of barley, is caused by dlumeria graminis barley specialized form (Blumeriagraminisf.sp.hordei).This pathogenic fungi belongs to Ascomycetes Erysiphales, and mainly in host's barley leaves epidermic cell, obligate live body is parasitic, can encroach on each organ of overground part of barley strain, but based on blade and leaf sheath, barley stem stalk and the fringe portion when weighing of falling ill also is encroached on ( 1994, Crit.Rev.PlantSci.).Barley powdery mildew mostly occurs at moist and semi-humid region, is distributed in each barley producing region, the world.On European Countries, Eastern North America and the ground such as southern areas, Japan, and the barley cultivation region such as the Guizhou of China, Sichuan and southeastern coast all has and generally occurs, generally can cause the production loss of 20%-25%, and heavy losses can reach 30% in the time of plant disease epidemic.In recent years, due to cultural factors such as barley variety simplification, high dense planting and excessive applied nitrogens, barley powdery mildew is fallen ill and is on the rise.

The preventing and controlling of current global barley powdery mildew complete mainly through using chemical pesticide.Triazole species (triazole) sterilant is organic heterocyclic compounds, for the wide spectrum of powdery mildew of cereals exploitation, interior suction, efficiently chemical bactericide over nearly 40 years, applied widely, using method is flexible, better to the prevention effect of barley powdery mildew.The mechanism of action of triazole bactericidal agent is the biosynthesizing suppressing pathogenic fungi ergosterol, somatic cells membrane structure and function are damaged, and then suppress or interference thalline appressorium and the growth of haustorium and the formation of mycelia and spore, reduce pathogenic fungi virulence.Wheat crops application triazole bactericidal agent prevents and treats the history that Powdery Mildew had for four more than ten years so far, and Powdery Mildew has produced resistance to triazole class compounds all research and report at home and abroad.Triazole bactericidal agent not only has germicidal action, also has plant growth regulation, therefore in use often has poisoning to occur, affect the yield and quality of crop.Meanwhile, a large amount of chemical bactericide that uses to environment, and can form potential threat to people and animals' safe diet and health.

Screening, cultivation and plantation disease-resistant variety are another important channels preventing and treating barley powdery mildew, find and identify that barley mildew-resistance gene is then the important ring in breeding for disease resistance work.The resistance of barley to Powdery Mildew comprises: one, relies on resistance specified (Shenetal, 2007, Science) that race specific resistance disease-resistant gene (as MLA gene) produces; Two, rely on the resistance of wide spectrum (Acevedo-Garciaetal, 2014, NewPhytol.) that non-race specific resistance disease-resistant gene (as mlo gene) produces; Three, rely on the partial resistance that non-race specific resistance disease-resistant gene produces.Combined by traditional breeding method mode and molecule marker assisting sifting, barley powdery mildew disease-resistant gene can be accelerated to import in Cultivar.

Barley powdery mildew bacteria has many physiological strains; The powder mildew resistance of the barley disease-resistant variety of main cultivation is often different from the powdery mildew dominant race of locality, therefore can not produce effective race specific resistance.And barley powdery mildew bacteria speed of mutation is fast, makes many a period of time effective race specific resistance disease-resistant genes lose resistance at short notice, become breeder's unsolved difficult problem always in selection and popularization barley disease-resistant variety process.Although use mlo gene that barley can be made to produce efficient resistance of wide spectrum to powdery mildew, but also can accelerate the apoptosis of crop simultaneously, reduce crop to the defence capability of other diseases, finally affect crop yield, therefore the application mlo gene in resistance breeding also has significant limitation (Acevedo-Garciaetal, 2014, NewPhytol.).In recent years, gene silencing (RNAinterference, RNAi) technology obtains a wide range of applications (KochandKogel in farm crop prevention and elimination of disease and pests field, 2014, PlantBiotechnol.J.), but the target gene of the tiny RNA of overexpression institute negative regulation mostly from harmful organism (as virus, bacterium, fungi, nematode and insect etc.).

MicroRNA (miRNA) is the small RNA molecular that a class length is generally about 21 Nucleotide, derive from the single stranded RNA precursor that can form loop-stem structure, and the target gene of complementary pairing site-specific by base, negative regulation is carried out to the expression of this gene.In plant, miRNA not only participates in the regulation and control to vine growth and development and the tolerance to abiotic stress, also participates in resisting the biotic processes such as extraneous pathogen infection.Noticeable change can be there is in the expression amount of miRNA in the interaction of plant and pathogenic bacteria, and miRNA synthesis defect mutant is more responsive to pathogenic bacteria invasion performance, illustrate that miRNA is necessary functional element in plant defense system, to Plant defense responses, there is important regulating and controlling effect (Weibergetal, 2014, Annu.Rev.Phytopathol.).Such as in Arabidopis thaliana, important acceptor TIR1, AFB2 and AFB3 of miR393 target growth hormone signal, the signal transduction process of Developing restraint element, and strengthen the resistance (Navarroetal, 2006, Science) of plant to pseudomonas.Increasing evidence shows in recent years, and miRNA plays important regulating effect in the resistance mechanism of various crop for multiple pathogenic bacteria.The action oriented research using microRNA sequences control crop autogene to reach control fungal disease object still rarely has report.

Summary of the invention

The object of the present invention is to provide a kind of miRNA relevant to barley mildew-resistance.

Another object of the present invention is to provide this miRNA improving the purposes in barley mildew-resistance resistance.

First the present invention finds that a kind of miRNA infects the expression amount generation considerable change in barley process at powdery mildew, and this miRNA called after miR159a, its nucleotide sequence is as shown in SEQIDNO.1.The present invention utilizes the method for stem-loopreal-timeqPCR to have detected the gene expression abundance of miR159a in the barley leaves sample of inoculation powdery mildew, finds that the expression amount of miR159a all significantly raises in affine and non-affine interaction at barley-powdery mildew.

Therefore, the invention provides the miRNA relevant to barley mildew-resistance, it is miR159a, and its nucleotide sequence is as shown in SEQIDNO.1.

The nucleotide sequence of miR159a precursor is as shown in SEQIDNO.2.

The present invention utilizes psRNATarget analysis platform to predict the target gene of miR159a in barley, find that a transcription factor GAMYB gene may be the target gene of miR159a, then find that process LAN miR159a significantly can reduce the accumulating level of GAMYB albumen by the experiment of tobacco coexpression, thus demonstrate the target gene that GAMYB is miR159a really, and it expresses the negative regulation by miR159a.The nucleotide sequence of the target gene GAMYB of miR159a is as shown in SEQIDNO.3.

Expression vector containing the miR159a relevant to barley mildew-resistance of the present invention also belongs to protection scope of the present invention.

The present invention utilizes the target gene GAMYB of particle bombardment instantaneous process LAN miR159a in barley epidermic cell, find that Barley Cells lowers the resistance of powdery mildew, especially remarkable in non-affine interaction, the haustorium index showing as powdery mildew significantly raises, illustrate that GAMYB gene is the inhibitors of barley mildew-resistance, and the miR159a of negative regulation GAMYB genetic expression can positive regulation barley to the resistance of Powdery Mildew.

Further, the invention provides miR159a or its application of expression vector in negative regulation GAMYB gene expressed promotor or contain it.

Further, the invention provides miR159a or its application of expression vector in raising barley mildew-resistance resistance expressed promotor or contain it.

Further, the invention provides miR159a or its application of expression vector in Barley Genetic Germplasm improvement expressed promotor or contain it.

The invention provides miR159a or its expression promotor or the expression vector containing it and prepare the application in transgene barley.

The invention provides the PCR Auele Specific Primer pair for cloning miR159a, upstream primer is as shown in SEQIDNO.7, and downstream primer is as shown in SEQIDNO.8.

The invention provides containing the right application of test kit in screening cultivation mildew-resistance barley of above-mentioned Auele Specific Primer.

The present invention finds that GAMYB gene is the inhibitors of barley mildew-resistance, and its process LAN can reduce barley mildew-resistance resistance.

Therefore, the process LAN that present invention also offers GAMYB gene is reducing the application in barley mildew-resistance resistance.The nucleotide sequence of described GAMYB gene is as shown in SEQIDNO.3, and its aminoacid sequence is as shown in SEQIDNO.15.

Present invention also offers the Specific PCR primers pair of clone GAMYB gene, the nucleotide sequence of its upstream and downstream primer is respectively as shown in SEQIDNO.5,6.

The present invention, by the analysis to miRNA express spectra, finds that miR159a infects expression amount in barley process at powdery mildew and significantly rises, and illustrates that miR159a participates in the process of barley defence melon infected with powdery mildew fungus and plays biological function; Overexpression miR159a and target gene GAMYB thereof the while that the present invention passing through in plant, finds that overexpression miR159a obviously can suppress the accumulation of GAMYB albumen, miR159a target GAMYB gene is described and its expression of negative regulation; Inoculate Powdery Mildew by the target gene GAMYB gene of process LAN miR159a instantaneous in barley epidermic cell, find that the resistance of barley to Powdery Mildew obviously reduces, illustrate that miR159a can strengthen the resistance of barley to powdery mildew.MiR159a provided by the invention can be widely used in barley genetic breeding, germ plasm resource improvement and cultivate the field of transgenic plants of mildew-resistance, has vital role to the germ plasm resource improving and improve the crops such as barley.

Accompanying drawing explanation

Fig. 1 is the effect diagram that powdery mildew infects to barley miR159a expression level.

Fig. 2 is the complementary case figure of target position point base sequence in miR159a and GAMYB, shows the base complementrity situation of miR159a target site in miR159a nucleotide sequence and GAMYB gene transcript mRNA sequence in figure.Wherein, base complete complementary indicates with perpendicular thick stick.

Fig. 3 is the carrier segment schematic diagram for process LAN miR159a and GAMYB gene in tobacco.Show in figure in the carrier used of process LAN miR159a and GAMYB gene in tobacco and express framework accordingly.Wherein, HA tag fusion to the C-terminal of GAMYB albumen, for the accumulation volume by Western blotting monitoring GAMYB albumen; In figure, arrows goes out in GAMYB gene by the site of miR159a target.

Fig. 4 is the design sketch that process LAN miR159a suppresses the accumulation of GAMYB albumen in tobacco.Indicate with "+" number containing during this over-express vector in experiment process, do not indicate with "-" number containing during this over-express vector.Utilize the antibody of HA label, detect that the accumulation volume of HA represents the accumulation volume of its fusion rotein GAMYB by Western blotting, and ponceau dyestuff (quantitative protein applied sample amount dyestuff) dyeing shows the protein sample applied sample amount uniformity of different experiments process.In the experiment detecting miR159a expression amount, Yeast Nucleic Acid amount uniformity used in the different experiments process of the detection display to the expression amount of the Actin muscle as internal reference.

Fig. 5 is that the target gene GAMYB of process LAN miR159a in barley epidermic cell is on the impact of barley powdery mildew bacteria resistance.Powdery mildew haustorium index represents the susceptibility of barley epidermis transformant, and numerical value higher explanation barley epidermic cell is more susceptible.With toxicity powdery mildew microspecies A6 (the left figure of Fig. 5) and nontoxic powdery mildew microspecies K1 (the right figure of Fig. 5) inoculate instantaneous process LAN empty carrier or GAMYB gene, after the blade of barley variety P01 containing MLA1 gene in genetic background, can find out that the target gene GAMYB of process LAN miR159a can cause Barley Cells to decline all to some extent to the background resistance (the left figure of Fig. 5) of powdery mildew and race specific resistance (the right figure of Fig. 5).

Embodiment

Following examples for illustration of the present invention, but are not used for limiting the scope of the invention.Without departing from the spirit and substance of the case in the present invention, the amendment do the inventive method, step or condition or replacement, all belong to scope of the present invention.

If do not specialize, chemical reagent used in embodiment is conventional commercial reagent, the conventional means that technique means used in embodiment is well known to those skilled in the art.The barley variety used in embodiment is P01, is documented in Shenetal, and in 2007, Science, the public can obtain from Chinese Academy of Sciences's heredity and developmental biology institute (hereinafter referred to as " heredity institute of the Chinese Academy of Sciences "); Large wheat powdery mildew (Blumeriagraminisf.sp.hordei) physiological strain K1 and A6 is documented in Shenetal, and in 2003, PlantCell, the public can obtain from Chinese Academy of Sciences's heredity; CTAP carrier is documented in Baietal, and in 2012, PLoSPathog., the public can obtain from Chinese Academy of Sciences's heredity; PKANNIBAL carrier is documented in Liuetal, and in 2014, PLoSGenet., the public can obtain from Chinese Academy of Sciences's heredity; PUbi carrier is documented in Shenetal, and in 2003, PlantCell, the public can obtain from Chinese Academy of Sciences's heredity.

Embodiment 1miR159a infects the expression pattern analysis in barley process at large wheat powdery mildew

(1) preparation of vegetable material.After barley variety P01 planting seed, wait to grow to about 1 week, cut boot leaf, blade face upward, be positioned over containing substratum (1% agar, 100mg/L benzimidazole) culture dish on, recover to inoculate barley powdery mildew bacteria physiological strain K1 or A6 respectively after 24 hours, and respectively after inoculation different time points get blade material.

(2) extraction of plant total serum IgE.In liquid nitrogen, grinding 300mg barley leaves, to Powdered, adds 1mlTRizol rapidly, in 4 DEG C of 12,000rpm centrifugal 10min after abundant concussion mixing; Supernatant is transferred in new centrifuge tube, adds the chloroform of 1/5TRizol volume, and after mixing, room temperature leaves standstill 3min and waits for its layering, afterwards in 4 DEG C of 12,000g centrifugal 15min.Supernatant is transferred in new centrifuge tube, first adds the 3M sodium-acetate (pH5.2) of supernatant volume 10%, adds the Virahol of supernatant volume 1 times after mixing again, leaves standstill 60min after mixing in-20 DEG C.4 DEG C of 10,000g centrifugal 15min, abandons supernatant, and by 75% washing with alcohol precipitation twice, each room temperature leaves standstill 10min, afterwards 4 DEG C of centrifugal 5min of 7500rpm, and precipitation at room temperature hangs 10min.By 60 μ lDEPC water dissolution precipitations, the plant total serum IgE of acquisition.

(3) reverse transcription reaction of Stem-loopreal-timeqPCR.

Primer needed for reaction: 5'-GTCGTATCCAGTGCAGGGTCCGAGGTATTCGCACTGGATACGACCAGAGCT-3 '.(SEQIDNO.4)

Reverse transcription system is: dNTP1 μ l, 50nMstem-loopRTprimer1 μ l, adds DEPCH ₂o to 10 μ l, 65 DEG C of sex change 5min, cooled on ice 2min; Add 10 × M-MLVbuffer2 μ l afterwards, RNaseinhibitor0.5 μ l, M-MLV1 μ l, total serum IgE 2 μ g, adds DEPCH ₂o to 20 μ l.Reverse transcription condition is: 16 DEG C of 30min, 42 DEG C of 30min, 85 DEG C of 5min.

(3) other experimental technique reference Chenetal of Stem-loopreal-timeqPCR, 2007, NucleicAcidsRes..According to following system configurations fluorescence quantitative PCR reaction solution: 2 × qPCRMix5 μ l, 100xCXR0.1 μ l, 10 μMs of forward primer 0.2 μ l, 10 μMs of reverse primer 0.2 μ l, add ddH ₂o to 10 μ l.Then, be dispensed in the special tubule of qPCR by above-mentioned reaction solution with 8 μ l/ pipes, often pipe adds 2 μ l template cDNA mixing to be measured respectively, and the centrifugal reaction solution that makes is gathered at the bottom of pipe, epiphragma.Then, react on ABI quantitative real time PCR Instrument according to following program: 95 DEG C of 10min, 95 DEG C of 15sec, 60 DEG C of 1min, 40 circulations.Arrange solubility curve: 95 DEG C of 10sec, 65 DEG C of 1min, 0.2 DEG C of ladder-elevating temperature, reads fluorescent value, is warming up to 95 DEG C of end.The qPCR primer detected needed for miR159a expression amount is as follows:

Forward: 5'-CGGCGGTTTGGATTGAAGGGA-3'; (SEQIDNO.9)

Reverse: 5'-GTGCAGGGTCCGAGGT-3'; (SEQIDNO.10)

The barley variety P01 of MLA1 gene is contained by toxicity powdery mildew microspecies A6 and nontoxic powdery mildew microspecies K1 inoculation genetic background, leaf sample is gathered after 0,4,16,22 and 48 hours in inoculation, and detect the relative expression quantity of miR159a in leaf tissue, and then research powdery mildew infects the impact on barley miR159a expression level.The relative expression quantity of miR159a in these leaf samples can be detected by Stem-loopreal-timeqPCR method.Experimental result is shown in Fig. 1, inoculates barley variety P01 and can reflect the background resistance of barley to powdery mildew, and can reflect the race specific resistance of barley to powdery mildew with nontoxic powdery mildew microspecies K1 inoculation barley variety P01 with toxicity powdery mildew microspecies A6.Result shows, no matter in the background resistance after inoculation toxicity powdery mildew microspecies, or in the race specific resistance after the nontoxic powdery mildew microspecies of inoculation, in Barley Cells, the gene expression abundance of miR159a changes all in time remarkable rising, illustrates that miR159a participates in barley and plays corresponding biological function to the resistance processes of Powdery Mildew.The nucleotide sequence of miR159a is as shown in SEQIDNO.1, and the nucleotide sequence of its precursor is as shown in SEQIDNO.2.

The prediction of embodiment 2 pairs of miR159a target gene GAMYB genes and clone

(1) miRNA target gene prediction.

Complete online on psRNATarget website the prediction of miR159a target gene, optimum configurations is acquiescence.(psRNATarget station address: http://plantgrn.noble.org/psRNATarget/) finds that transcription factor GAMYB gene may be the target gene (see Fig. 2) of miR159a.

(2) clone of GAMYB gene.7 days seedling inoculation large wheat powdery mildew physiological strain K1 of barley variety P01, got blade material after 24 hours, carry out reverse transcription and obtain cDNA after extracting RNA.Reverse transcription system and process as follows: RNA2 μ g, Oligo-dT1 μ l, adds DEPC-H ₂o to 12 μ l, centrifuge tube mixes in 70 DEG C of sex change 10 minutes after above-mentioned solution, then in cooled on ice 2 minutes, continue afterwards to add M-MLVBuffer2 μ l in centrifuge tube, dNTPmix1 μ l, RNaseinhibitor0.5 μ l, M-MLV1 μ l, added DEPC-H ₂o to 20 μ l, in 42 DEG C of temperature baths 1 hour, 70 DEG C of insulations obtained the cDNA of reverse transcription after 15 minutes.

The primer needed for pcr amplification of clone GAMYB gene is as follows:

Forward: 5'-ATGTACCGGGTGAAGAGCGAG-3'; (SEQIDNO.5)

Reverse: 5'-TTTGAATTCCTCCGACATTTGAC-3'(SEQIDNO.6).

PCR reaction system is: KODbuffer5 μ l, MgSO ₄2 μ l, dNTP5 μ l, cDNA2 μ l, each 1 μ l of forward and reverse primer, KODplus enzyme 1 μ l, adds H ₂o to 50 μ l.PCR response procedures is: 94 DEG C of 3min+ (94 DEG C 30s+58 DEG C 30s+68 DEG C of 90s) × 30 circulations+68 DEG C of 10min.

Be obtained by reacting the PCR primer of 1662bp, this PCR primer checked order, result for the nucleotide sequence shown in sequence in sequence table 3, the unnamed gene shown in this sequence be GAMYB; The protein designations of this genes encoding is GAMYB, and the aminoacid sequence of this albumen is the sequence 15 in sequence table.

Its checking expressed of embodiment 3 pairs of miR159a target GAMYB genes negative regulation

(1) miR159a and target gene GAMYB thereof is cloned in expression vector pKANNIBAL and CTAP respectively.

The primer needed for pcr amplification of clone miR159a is as follows:

Forward: 5'-GTTCCTCGAGCCGTTCCATATCTTCTAGCCCC-3'; (SEQIDNO.7)

Reverse: 5'-CCTCAAGCTTTTGAGGGGAAAACAAAACACCG-3'(SEQIDNO.8).

The primer needed for pcr amplification of clone GAMYB gene is as follows:

Forward: 5'-ATGTACCGGGTGAAGAGCGAG-3'(SEQIDNO.5);

Reverse: 5'-TTTGAATTCCTCCGACATTTGAC-3'(SEQIDNO.6).

In tobacco, in process LAN miR159a and GAMYB gene carrier used, corresponding framework of expressing is shown in Fig. 3.

(2) conversion of Agrobacterium.Agrobacterium strains GV3101 is streak culture on LB solid medium, and picking list bacterium colony after two days, trains 180rpm28 DEG C of incubated overnight in liquid base at LB.Overnight culture enlarged culturing is to OD ₆₀₀be after 0.5, bacterium liquid is placed in 30 minutes on ice, 4 DEG C of 3000rpm collect thalline after centrifugal 15 minutes, and with the resuspended thalline of precooling NaCl solution of 10ml0.15M, 4 DEG C of 5000rpm collect thalline after centrifugal 10 minutes again.With the 20mMCaCl of 1ml precooling ₂the resuspended thalline of solution, adds 0.5mL50% glycerine, and fully mixing obtains Agrobacterium competent cell.In Agrobacterium competent cell, add expression vector dna, blow and beat mixing gently, be placed in and use liquid nitrogen flash freezer 1 minute after 30 minutes on ice, then use 37 DEG C of water-bath heat shocks 3 minutes.Add 1mlLB nutrient solution 28 DEG C of 180rpm and cultivate 30 minutes, coat and be added with on corresponding antibiotic LB solid medium, be inverted cultivation selected clone after 2 days for 28 DEG C, preserve Agrobacterium-mediated Transformation body.

(3) the instantaneous coexpression in tobacco leaf with agriculture bacillus mediated miR159a and target GAMYB gene thereof.The agrobacterium strains transforming corresponding expression vectors is rule on LB solid medium, the single bacterium colony of picking Agrobacterium after two days, 230rpm28 DEG C of overnight incubation in LB nutrient solution.Overnight culture is transferred in 8mlLB nutrient solution (containing 10mMMES and 0.02mM Syringylethanone) by 1:50, and succeeding transfer culture is to OD ₆₀₀be that 1.5 rear 3000rpm collect thalline in centrifugal 15 minutes, resuspended thalline is to OD ₆₀₀it is tobacco (Nicotianabenthamiana) blade that 0.7,24 DEG C of lucifuges leave standstill 4 hr later injection, 4 weeks sizes.After in tobacco leaf, injection has transformed the agrobacterium strains of miR159a expression vector, 24h is cultivated in moisturizing, the agrobacterium strains having transformed GAMYB expression vector is again injected at injection original position, get the leaf tissue of injection position after cultivating 48h, extract total serum IgE and total protein.

(4) miR159a expression analysis and the component analysis of GAMYB protein accumulation.Reverse transcription is carried out to the tobacco leaf total serum IgE extracted and obtains cDNA, the reference gene Actin (actin gene) of the sample that increases under different cycle numbers according to RT-PCR reaction system and condition.Whether PCR primer detects through agarose gel electrophoresis, consistent by DNA band brightness inspection template amount; If inconsistent, template higher for product brightness is carried out the dilution of certain multiple, until product brightness is basically identical.Now, by the expression amount (Fig. 4) of RT-PCR reaction detection miR159a.Utilize anti-HA polyclonal antibody, the accumulation volume (Fig. 4) of GAMYB albumen in tobacco leaf total protein is detected by Western blotting, by corresponding expression vector, utilize agriculture bacillus mediated miR159a and GAMYB albumen instantaneous coexpression in tobacco, and using the instantaneous coexpression of empty carrier and GAMYB as negative contrast, research process LAN miR159a is on the impact of GAMYB protein accumulation.

The qPCR primer detected needed for miR159a expression amount is as follows:

Forward: 5'-CGGCGGTTTGGATTGAAGGGA-3'; (SEQIDNO.9)

Reverse: 5'-GTGCAGGGTCCGAGGT-3'; (SEQIDNO.10)

Internal reference ACTIN1 (Actin muscle) forward: 5'-TGGCACCCGAGGAGCACC-3'; (SEQIDNO.11)

Internal reference ACTIN1 (Actin muscle) is reverse: 5'-GTAACCTCTCTCGGTGAG-3'.(SEQIDNO.12)

Experimental result shows, after passing through to note agrobacterium co-cultivation process LAN miR159a altogether, significantly can suppress the accumulation (Fig. 4) of GAMYB albumen, miR159a certain target GAMYB gene is described and its protein accumulation amount of negative regulation in tobacco.Due to the expression amount of miR159a negative regulation GAMYB gene, miR159a barley to the effect in powder mildew resistance, contrary to the effect in powder mildew resistance barley with GAMYB gene.As coexpression empty carrier and GAMYB, GAMYB albumen has the accumulation of some amount, and during coexpression miR159a and GAMYB, can't detect the accumulation of GAMYB albumen, illustrates that process LAN miR159a can suppress the accumulation of GAMYB albumen in tobacco.

In embodiment 4 barley epidermic cell, process LAN miR159a target gene GAMYB is to the research of barley powdery mildew bacteria resistance

(1) miR159a target gene GAMYB is cloned in cloning vector pENTRY, and reacts this gene integration in expression vector CTAP further by LR.

Primer needed for clone GAMYB gene is as follows:

Forward: 5'-GGGGACAAGTTTGTACAAAAAAGCAGGCTTCATGTACC

GGGTGAAGAGCGAG-3'；(SEQIDNO.13)

Reverse: 5'-GGGGACCACTTTGTACAAGAAAGCTGGGTCTTTGAATT

CCTCCGACATTTGAC-3'。(SEQIDNO.14)

(2) the instantaneous process LAN of the unicellular gene of barley of particle gun mediation.Get 9mg bronze, add 1ml70% ethanol after drying 4h at 65 DEG C, concussion cleaning 5min, leaves standstill 15min sedimentation, abandons supernatant after centrifugal 2 seconds.Shake 2min after adding 1ml sterilizing deionized water, to place after 1min centrifugal 2 seconds, abandon supernatant.1ml50% glycerine is added, concussion mixing after repeating 2 times.After ready bronze concussion 5min, plasmid DNA and gus reporter gene expression plasmid etc. mole are mixed, adds deionized water to 5 μ l; In 50 μ l bronzes, add plasmid DNA cocktail, while earthquake, dropwise add 50 μ l2.5MCaCl ₂, then add 20 μ l0.1M spermidines fast, continue concussion 3min.Leave standstill 1min sedimentation, abandon supernatant, use 140 μ l70% ethanol and 140 μ l100% washing with alcohol respectively after centrifugal 2 seconds, after adding 12 μ l100% ethanol afterwards, concussion mixes.

Use model is bombarded for the particle gun of PDS-1000/Hedeliverysystem (Bio-Rad).Carrier film is put in carrier film supporting disk, by bronze uniform application airing after carrier film central authorities; Explosion diaphragm is placed into explosion diaphragm chuck, is fixed on accelerator; Carrier film supporting disk is added stop net, is placed into bombardment room the first layer, and will carry after vaned flat board is placed on third layer and vacuumize, reach after 27 inches of mercury until vacuum values and launch bombardment.After bombardment, blade is set on culture dish, put into growth cabinet quiescent culture.

(3) powdery mildew and haustorium index statistics is inoculated.Getting barley strain with ripe powdery mildew spores when connecing bacterium accepting to shake gently above the blade of biolistic bombardment, making spore even drop down; Seal culture dish after leaving standstill 3min, put into growth cabinet quiescent culture.Be immersed in GUS staining fluid by the barley isolated blade cultivating 48h and dye, vacuumize 3 times, each 5min, period puts upside down gently; 37 DEG C are incubated overnight, and afterwards blade are immersed in room temperature in destainer and decolour two days.Blade is cleaned 1h in clear water, dyes 10 seconds in Coomassie Brillant Blue solution, clean 2 times with water; Face of blade is placed on slide glass upward, drips 50% glycerine, presses cover glass, examine under a microscope.Cell number that add up susceptible (containing haustorium and secondary mycelia) and disease-resistant (only having appressorium) respectively, that express GUS, susceptible cell number is haustorium index with the ratio of statistics cell number summation.

This experiment utilizes particle gun to mediate the target gene GAMYB of instantaneous process LAN miR159a in barley epidermis is unicellular, with instantaneous process LAN empty carrier for negative contrast, in conjunction with after powdery mildew inoculation and haustorium index add up, have studied the target gene GAMYB of process LAN miR159a in barley epidermic cell to the impact of barley powdery mildew bacteria resistance.Experimental result shows, after the target gene GAMYB of the unicellular middle particle bombardment process LAN miR159a of barley epidermis, the background resistance of Barley Cells to powdery mildew declines to some extent, show as and comparatively contrast rising (the left figure of Fig. 5) to some extent at inoculation toxicity powdery mildew microspecies opisthaptor index, and Barley Cells obviously declines to the race specific resistance of powdery mildew, show as the nontoxic powdery mildew microspecies opisthaptor index of inoculation and comparatively contrast obvious rising (the right figure of Fig. 5), illustrate that GAMYB gene is the inhibitors of barley mildew-resistance, further illustrating miR159a can regulate Barley Cells to the disease resistance of powdery mildew by forward.

Although above the present invention is described in detail with a general description of the specific embodiments, on basis of the present invention, can make some modifications or improvements it, this will be apparent to those skilled in the art.Therefore, these modifications or improvements without departing from theon the basis of the spirit of the present invention, all belong to the scope of protection of present invention.

Claims (10)

1. the miRNA relevant to barley mildew-resistance, it is miR159a, and its nucleotide sequence is as shown in SEQIDNO.1.

2. as claimed in claim 1 relevant to barley mildew-resistance miRNA, the nucleotide sequence of its precursor is as shown in SEQIDNO.2.

3. as claimed in claim 1 relevant to barley mildew-resistance miRNA, it is characterized in that, its target gene is GAMYB gene, and the nucleotide sequence of GAMYB gene is as shown in SEQIDNO.3.

4. the expression vector containing the arbitrary described miRNA relevant to barley mildew-resistance of claim 1-3.

5. the miRNA relevant to barley mildew-resistance as described in as arbitrary in claim 1-3 or its express the application of the expression vector shown in promotor or claim 4 in negative regulation GAMYB gene.

6. the miRNA relevant to barley mildew-resistance as described in as arbitrary in claim 1-3 or its express the expression vector shown in promotor or claim 4 and improving the application in barley mildew-resistance resistance.

7. the miRNA relevant to barley mildew-resistance as described in as arbitrary in claim 1-3 or its express the application of the expression vector shown in promotor or claim 4 in Barley Genetic Germplasm is improved.

8. the miRNA relevant to barley mildew-resistance as described in as arbitrary in claim 1-3 or its express the expression vector shown in promotor or claim 4 and preparing the application in transgene barley.

9. for cloning the PCR Auele Specific Primer pair of miR159a, it is characterized in that, upstream primer is as shown in SEQIDNO.7, and downstream primer is as shown in SEQIDNO.8.

10. containing the application of test kit in screening cultivation mildew-resistance barley that the Auele Specific Primer shown in claim 9 is right.