CN116947995A

CN116947995A - American ginseng PqEXPA14 protein, and coding gene and application thereof

Info

Publication number: CN116947995A
Application number: CN202311029946.6A
Authority: CN
Inventors: 袁媛; 王腾腾; 赵玉洋; 黄璐琦
Original assignee: Institute of Materia Medica of CAMS
Current assignee: Institute of Materia Medica of CAMS
Priority date: 2023-08-16
Filing date: 2023-08-16
Publication date: 2023-10-27

Abstract

The application discloses American ginseng PqEXPA14 protein, and a coding gene and application thereof. The application relates to the field of medicinal plant molecular biology, in particular to American ginseng PqEXPA14 protein, and a coding gene and application thereof. The PqEXPA14 protein of the application is A1) and the amino acid sequence is SEQ ID No.1; a2 Protein obtained by substituting and/or deleting and/or adding amino acid residues of the protein of A1) has more than 80% of identity with the protein shown in A1) and has the function of regulating and controlling the ginsenoside content of plant tissues; a3 Fusion proteins obtained by ligating protein tags at the N-terminal or/and C-terminal of A1) or A2). The RNAi interference vector of the PqEXPA14 is constructed and transferred into American ginseng callus, and the result of ginsenoside detection of the transgenic callus shows that the content of ginsenoside can be improved by interfering the expression of the PqEXPA14 gene.

Description

American ginseng PqEXPA14 protein, and coding gene and application thereof

Technical Field

The application relates to the field of medicinal plant molecular biology, in particular to American ginseng PqEXPA14 protein, and a coding gene and application thereof.

Background

American ginseng (Panax quinquefolium L.) is a traditional Chinese medicine in China, has the effects of tonifying qi and yin, clearing heat and promoting the production of body fluid and the like, and is mostly used for symptoms such as qi deficiency and yin deficiency, internal heat, cough and asthma, phlegm blood, dysphoria due to deficiency heat and the like. Ginsenoside is a main medicinal component in American ginseng, has obvious effects in reducing blood fat, improving myocardial ischemia of human body, preventing cancer and the like, and has extremely high medical value and health care value.

In recent years, the market demand of American ginseng is rapidly increased, and clinical medication is in short supply, but American ginseng has higher requirements on growth environment, climate, cultivation technology and the like, and manual cultivation is difficult to meet the current clinical demands. The plant tissue culture technology can avoid the defects brought by field cultivation, has the advantages of short production period, no environmental limitation, plant resource protection and the like, and provides a cost-effective means for the mass production of active ingredients of medicinal plants. Although tissue culture of American ginseng callus is a way for rapidly obtaining ginsenoside, the yield of the ginsenoside obtained by the way is low and cannot meet the market demand, so that the improvement of the content of the ginsenoside in the American ginseng callus by means of manual means has important significance.

Disclosure of Invention

The application aims to solve the technical problem of regulating and controlling the ginsenoside content of plant tissues.

In order to solve the problems existing in the prior art, the application provides a protein.

The protein provided by the application can be any one of the following proteins:

a1 Protein with the amino acid sequence shown as SEQ ID No.1;

a2 Protein obtained by substituting and/or deleting and/or adding amino acid residues of the protein of A1) has more than 80% of identity with the protein shown in A1) and has the function of regulating and controlling the ginsenoside content of plant tissues; for example, according to the amino acid sequence shown as SEQ ID No.1 and the conventional technical means in the art such as conservative substitution of amino acid, one or more amino acids can be substituted, deleted and/or added by a person skilled in the art on the premise of not affecting the activity of the protein mutant, so that the protein mutant with the same function as the amino acid sequence shown as SEQ ID No.1 is obtained;

a3 Fusion proteins obtained by ligating protein tags at the N-terminal or/and C-terminal of A1) or A2).

The protein described in A1) above is named PqEXPA14.

In order to facilitate purification or detection of the protein of A1), a tag protein may be attached to the amino-or carboxy-terminus of the protein consisting of the amino acid sequence shown in SEQ ID No.1 of the sequence Listing.

The protein can be synthesized artificially or obtained by synthesizing the coding gene and then biologically expressing.

Such tag proteins include, but are not limited to: GST (glutathione-sulfhydryl transferase) tag protein, his6 tag protein (His-tag), MBP (maltose binding protein) tag protein, flag tag protein, SUMO tag protein, HA tag protein, myc tag protein, eGFP (enhanced green fluorescent protein), eFP (enhanced cyan fluorescent protein), eYFP (enhanced yellow green fluorescent protein), mCherry (monomeric red fluorescent protein) or AviTag tag protein.

The nucleotide sequence encoding the protein PqEXPA14 of the present application can be easily mutated by a person skilled in the art using known methods, such as directed evolution or point mutation. Those artificially modified nucleotides having 75% or more identity to the nucleotide sequence of the protein PqEXPA14 isolated by the present application are all derived from the nucleotide sequence of the present application and are equivalent to the sequence of the present application, as long as they encode the protein PqEXPA14 and have the function of the protein PqEXPA14.

The 75% or more identity may be 80%, 85%, 90% or 95% or more identity.

Herein, identity refers to identity of an amino acid sequence or a nucleotide sequence. The identity of amino acid sequences can be determined using homology search sites on the internet, such as BLAST web pages of the NCBI homepage website. For example, in advanced BLAST2.1, the identity of a pair of amino acid sequences can be searched for by using blastp as a program, setting the Expect value to 10, setting all filters to OFF, using BLOSUM62 as Matrix, setting Gap existence cost, per residue gap cost and Lambda ratio to 11,1 and 0.85 (default values), respectively, and calculating, and then obtaining the value (%) of the identity.

Herein, the 80% identity or more may be at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identity.

Herein, the 90% identity or more may be at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identity.

Above, the protein is derived from American ginseng (Panax quinquefolium l.).

The present application also provides a biological material related to the above protein, which may be any one of the following:

b1 A nucleic acid molecule encoding a protein as described above;

b2 An expression cassette comprising the nucleic acid molecule of B1);

b3 A recombinant vector comprising the nucleic acid molecule of B1) or a recombinant vector comprising the expression cassette of B2);

b4 A recombinant microorganism comprising the nucleic acid molecule of B1), or a recombinant microorganism comprising the expression cassette of B2), or a recombinant microorganism comprising the recombinant vector of B3);

b5 A transgenic plant cell line comprising the nucleic acid molecule of B1) or a transgenic plant cell line comprising the expression cassette of B2);

b6 A transgenic plant tissue comprising the nucleic acid molecule of B1) or a transgenic plant tissue comprising the expression cassette of B2);

b7 A transgenic plant organ comprising the nucleic acid molecule of B1) or a transgenic plant organ comprising the expression cassette of B2);

c1 A nucleic acid molecule that inhibits or reduces or silences the expression of a gene encoding a protein as described above;

c2 Expression of the gene encoding the nucleic acid molecule of C1);

c3 An expression cassette containing the coding gene of C2);

c4 A recombinant vector comprising the coding gene of C2) or a recombinant vector comprising the expression cassette of C3);

c5 A recombinant microorganism containing the gene encoding C2), or a recombinant microorganism containing the expression cassette of C3), or a recombinant microorganism containing the recombinant vector of C4);

c6 A transgenic plant cell line containing the coding gene of C2), or a transgenic plant cell line containing the expression cassette of C3), or a transgenic plant cell line containing the recombinant vector of C4);

c7 A transgenic plant tissue containing C2) said coding gene, or a transgenic plant tissue containing C3) said expression cassette, or a transgenic plant tissue containing C4) said recombinant vector;

c8 A transgenic plant organ containing the coding gene of C2), or a transgenic plant organ containing the expression cassette of C3), or a transgenic plant organ containing the recombinant vector of C4).

In the above biological material, the nucleic acid molecule of B1) is a gene represented by E1) or E2) as follows:

e1 A cDNA molecule or a DNA molecule of SEQ ID No. 2;

e2 The nucleotide encoding the strand is a cDNA molecule or a DNA molecule of SEQ ID No. 2.

The DNA molecule shown in SEQ ID No.2 (gene regulating ginsenoside content in plant tissue) encodes a protein PqEXPA14 whose amino acid sequence is SEQ ID No. 1.

The nucleotide sequence shown in SEQ ID No.2 is the nucleotide sequence of the protein PqEXPA14 encoding gene (CDS).

The PqEXPA14 gene of the present application may be any nucleotide sequence capable of encoding the protein PqEXPA14. In view of the degeneracy of codons and the preferences of codons of different species, one skilled in the art can use codons appropriate for expression of a particular species as desired.

B1 The nucleic acid molecules may also comprise nucleic acid molecules which have been modified by codon preference on the basis of the nucleotide sequence indicated in SEQ ID No. 2.

B1 The nucleic acid molecule may also include a nucleic acid molecule having a nucleotide sequence identity of 95% or more with the nucleotide sequence shown in SEQ ID No.2 and being of the same species.

The nucleic acid molecule described herein may be DNA, such as cDNA, genomic DNA, or recombinant DNA; the nucleic acid molecule may also be an RNA, such as gRNA, mRNA, siRNA, shRNA, sgRNA, miRNA or antisense RNA.

Vectors described herein are well known to those of skill in the art and include, but are not limited to: plasmids, phages (e.g., lambda phage or M13 filamentous phage, etc.), cosmids (i.e., cosmids), ti plasmids, or viral vectors. Specifically, it may be the vector pBWA (V) BS.

Recombinant expression vectors containing the PqEXPA14 gene can be constructed using existing plant expression vectors. Such plant expression vectors include, but are not limited to, vectors such as binary Agrobacterium vectors and vectors useful for microprojectile bombardment of plants, and the like. The plant expression vector may also comprise the 3' -untranslated region of a foreign gene, i.e., comprising a polyadenylation signal and any other DNA segments involved in mRNA processing or gene expression. The polyadenylation signal may direct the addition of polyadenylation to the 3 'end of the mRNA precursor and may function similarly to untranslated regions transcribed from the 3' end of plant genes including, but not limited to, agrobacterium tumefaciens induction (Ti) plasmid genes (e.g., nopaline synthase Nos genes), plant genes (e.g., soybean storage protein genes).

When the PqEXPA14 gene is used for constructing a recombinant plant expression vector, any one of an enhanced promoter or a constitutive promoter can be added before the transcription initiation nucleotide thereof, including, but not limited to, a cauliflower mosaic virus (CAMV) 35S promoter, a ubiquitin promoter (ubiquitin) of corn, which can be used alone or in combination with other plant promoters; in addition, when the gene of the present application is used to construct a plant expression vector, enhancers, including translational enhancers or transcriptional enhancers, may be used, and these enhancers may be ATG initiation codon or adjacent region initiation codon, etc., but must be identical to the reading frame of the coding sequence to ensure proper translation of the entire sequence. The sources of the translational control signals and initiation codons are broad, and can be either natural or synthetic. The translation initiation region may be derived from a transcription initiation region or a structural gene.

In order to facilitate the identification and selection of transgenic plant cells or plants, the plant expression vectors used may be processed, such as by adding genes encoding enzymes or luminescent compounds that produce a color change (GUS gene, luciferase gene, etc.), antibiotic markers with resistance (gentamicin markers, kanamycin markers, etc.), or anti-chemical marker genes (e.g., anti-herbicide genes), etc., which may be expressed in plants. From the safety of transgenic plants, transformed plants can be screened directly in stress without adding any selectable marker gene.

The PqEXPA14 gene or the fragment of the gene provided by the application is introduced into plant cells or receptor plants by using any vector capable of guiding the expression of exogenous genes in plants, so that a transgenic cell line and a transgenic plant with the content of ginsenoside in plant tissues changed can be obtained. The expression vector carrying the PqEXPA14 gene may be transformed into plant cells or tissues by using conventional biological methods such as Ti plasmid, ri plasmid, plant viral vector, direct DNA transformation, microinjection, conductance, agrobacterium mediation, etc., and the transformed plant tissues are cultivated into plants.

As a specific example, the above recombinant vector is recombinant vector pBWA (V) BS: pqEXPA14 _RNAi . The recombinant vector pBWA (V) BS: pqEXPA14 _RNAi Is a recombinant vector obtained by inserting a DNA fragment with a sequence of SEQ ID No.4 between restriction sites of restriction enzyme Bsa I of pBWA (V) BS vector and keeping other sequences of the pBWA (V) BS vector unchanged.

The microorganism described herein may be a yeast, bacterium, algae or fungus. Wherein the bacteria may be derived from Escherichia, erwinia, agrobacterium (Agrobacterium), flavobacterium (Flavobacterium), alcaligenes (Alcaligenes), pseudomonas, bacillus (Bacillus), etc. Specifically, agrobacterium tumefaciens EHA105.

The application also provides the use of the protein PqEXPA14 or a substance regulating the expression of a gene or a substance regulating the activity or content of said protein as described hereinbefore in any of the following:

u1) application of the protein or the expression substance of the regulatory gene or the substance for regulating the activity or the content of the protein in regulating the content of ginsenoside in plant tissues;

u2) the protein or the substance for regulating the expression of the gene or the substance for regulating the activity or the content of the protein is applied to the preparation of products for regulating the content of ginsenoside in plant tissues;

u3) the use of the protein or the substance regulating the expression of the gene or the substance regulating the activity or the content of the protein in cultivating plants with altered ginsenoside content in plant tissues;

u4) the use of the protein or the substance regulating the expression of the gene or the substance regulating the activity or the content of the protein in the preparation of a product for cultivating plants with altered ginsenoside content in plant tissues;

u5) the use of the protein or the substance regulating the expression of a gene or the substance regulating the activity or the content of the protein in plant breeding.

Herein, the substance that regulates the activity and/or content of the protein may be a substance that regulates the expression of a gene encoding the protein PqEXPA14.

In the above application, the substance for regulating the expression of the gene or the substance for regulating the activity or content of the protein is a biological material related to the protein, and the biological material may be any of the following:

b1 A nucleic acid molecule encoding a protein as described above;

b2 An expression cassette comprising the nucleic acid molecule of B1);

c2 Expression of the gene encoding the nucleic acid molecule of C1);

c3 An expression cassette containing the coding gene of C2);

In the above, the substance that regulates gene expression may be a substance that performs at least one of the following 6 regulation: 1) Regulation at the level of transcription of said gene; 2) Regulation after transcription of the gene (i.e., regulation of splicing or processing of the primary transcript of the gene); 3) Regulation of RNA transport of the gene (i.e., regulation of nuclear to cytoplasmic transport of mRNA of the gene); 4) Regulation of translation of the gene; 5) Regulation of mRNA degradation of the gene; 6) Post-translational regulation of the gene (i.e., regulation of the activity of the protein translated by the gene).

The application also provides a method for regulating and controlling the ginsenoside content of the plant tissue, which comprises regulating and controlling the activity and/or the content of the protein in the target plant, or/and the expression level of the coding gene of the protein, so as to regulate and control the ginsenoside content of the plant tissue.

In the method, the regulation of the activity and/or content of the protein PqEXPA14 in the target plant, or/and the expression level of the encoding gene of the protein comprises introducing a DNA molecule for inhibiting, reducing or silencing the encoding gene PqEXPA14 of the protein into a receptor plant to obtain the target plant with the plant tissue ginsenoside content changed; the PqEXPA14 encoding gene encodes the protein PqEXPA14.

The introduction refers to introduction by recombinant means including, but not limited to, agrobacterium (Agrobacterium) -mediated transformation, biolistic (biolistic) methods, electroporation, in planta technology, and the like.

In the above applications and methods, the modulation may be enhancement, enhancement or upregulation.

In the above applications and methods, the modulation may be inhibition, reduction or silencing.

Herein, the expression amount of the encoding gene that regulates the protein may be inhibition or reduction or down-regulation of the encoding gene expression. Inhibition or reduction or downregulation of expression of the coding gene may be achieved by gene knockout or gene silencing.

The gene knock-out refers to a phenomenon in which a specific target gene is inactivated by a gene editing technique. Gene knockdown inactivates specific target genes by DNA sequence changes, including, but not limited to, zinc-finger-nucleic acid (ZFN) -based, transcription activator-like effector nucleases (transcription activator-like effector nucleases, TALENs) and CRISPR/Cas systems, CRISPR (clustered regulatory interspaced short palindromic repeat), clustered regularly spaced short palindromic repeats, a locus in the genome containing multiple short repeats, with Cas9 proteins capable of cleaving crRNA-tracrRNA recognized target sequences under RNA mediation.

The gene silencing refers to the phenomenon that the gene is not expressed or expressed under the condition of not damaging the original DNA. Gene silencing is premised on the fact that the DNA sequence is not altered, so that the gene is not expressed or is underexpressed. Gene silencing can occur at two levels, one is gene silencing at the transcriptional level due to DNA methylation, heterochromatin, and positional effects, and the other is post-transcriptional gene silencing, i.e., inactivation of a gene by specific inhibition of a target RNA at the post-transcriptional level of the gene, including antisense RNA, co-suppression (co-suppression), gene suppression (sequencing), RNA interference (RNAi), and microrna (miRNA) -mediated translational inhibition, among others.

To facilitate identification and selection of transgenic cells or plants, the recombinant expression vectors used may be processed, for example by adding genes encoding enzymes or luminescent compounds which produce a color response, antibiotic markers or chemical resistance markers which are expressed in plants, etc. The transformed plants can also be screened directly in adversity without adding any selectable marker gene. The plants obtained by the above method may be transgenic plants, or plants obtained by conventional breeding techniques such as crossing. In the above methods, the transgenic plants are understood to include not only first to second generation transgenic plants but also their progeny. For transgenic plants, the gene may be propagated in that species, and may be transferred into other varieties of the same species, including particularly commercial varieties, using conventional breeding techniques. The transgenic plants include seeds, calli, whole plants and cells.

The application also provides a method for cultivating plants with modified ginsenoside content in plant tissues, which comprises the following steps: 1) Inhibiting or reducing or silencing the expression level of the coding gene of the protein in the target plant, or/and inhibiting or reducing or silencing the activity and/or content of the coding gene of the protein to obtain the plant with the plant tissue with the increased ginsenoside content;

2) Increasing, enhancing and/or upregulating the expression level of a gene encoding a protein as defined above in a plant of interest, or/and increasing, enhancing and/or upregulating the activity and/or content of a gene encoding a protein as defined above, to obtain a plant with reduced ginsenoside content in the tissue.

As an embodiment of the present application, the method for cultivating a plant with an altered ginsenoside content in a plant tissue comprises the steps of:

(1) Constructing an expression vector containing the expression quantity of the coding gene for regulating and controlling the protein in the target plant shown as SEQ ID No. 2;

(2) Introducing the expression vector constructed in the step (1) into a plant;

(3) Obtaining the plant with the plant tissue with the changed ginsenoside content through screening and identification.

In a specific embodiment, a method for growing plants with increased ginsenoside content in plant tissue comprises the steps of: inhibiting the expression of nucleic acid molecules encoding the PqEXPA14 protein in the target plant to obtain the transgenic plant with the tissue ginsenoside content increased.

In the present application, the inhibition of expression of a nucleic acid molecule encoding a PqEXPA14 protein in a plant of interest can be specifically achieved by introducing into the plant of interest an interfering vector targeting the nucleic acid molecule encoding the PqEXPA14 protein.

In the present application, the inhibition of expression of a nucleic acid molecule encoding a PqEXPA14 protein in a plant of interest can be specifically achieved by introducing a gene editing vector targeting a nucleic acid molecule encoding a PqEXPA14 protein into a plant of interest.

Specifically, the interfering vector targeting the nucleic acid molecule encoding the PqEXPA14 protein is pBWA (V) BS: pqEXPA14 _RNAi 。

The interference vector pBWA (V) BS: pqEXPA14 _RNAi Is an interference vector obtained by inserting a DNA fragment with a sequence of SEQ ID No.4 between restriction sites of restriction enzyme Bsa I of pBWA (V) BS vector and keeping other sequences of the pBWA (V) BS vector unchanged.

The method for transferring the interference vector into the American ginseng callus can be a gene gun method.

The method for detecting the ginsenoside content comprises the step of measuring the ginsenoside content of the transgenic callus by utilizing ultra-high performance liquid chromatography-triple quadrupole mass spectrometry (UPLC-MS/MS).

The ginsenoside is ginsenoside Rd, 20s-Rh ₁ 、Rb ₁ 、Rg ₁ 、Rg ₂ 、Re、R _f 、F ₁ 。

The ginsenoside content of the callus of the transgenic plant is obviously increased compared with the wild type.

In the present application, the plant tissue may be plant callus.

In the present application, the object of plant breeding includes growing plants with increased ginsenoside content in plant tissue.

In the above application or method, the plant is any one of the following:

c1 Dicotyledonous plants;

c2 Plant of the order umbelliferae;

c3 Araliaceae plant;

c4 Ginseng plant;

c5 American ginseng).

The application obtains the coding region sequence of the PqEXPA14 gene from the American ginseng cDNA, selects the specific RNAi fragment of the gene, constructs an RNAi interference vector and transfers the plant expression vector into the American ginseng callus. The result of ginsenoside detection on the obtained transgenic callus shows that the content of ginsenoside can be improved by interfering the expression of the PqEXPA14 gene. Compared with the wild type, the transgenic callus obtained by the experiment greatly improves the content of various ginsenosides, and provides an effective means for realizing industrialization and industrialization of the ginsenosides production by tissue culture of the American ginseng and solving the clinical deficiency of the American ginseng.

Drawings

FIG. 1 is pBWA (V) BS: pqEXPA14 _RNAi Vector map.

FIG. 2 shows the results of screening resistant calli.

FIG. 3 is a PCR assay of resistant calli. Wherein lane M: DNA Marker D2000 Plus; lane 1: pBWA (V) BS: pqEXPA14 _RNAi A vector plasmid; lanes 2-4: positive calli RNAi1, RNAi2, RNAi3,5: wild American ginseng callus; 6: sterile water.

FIG. 4 shows the analysis of the expression level of the pqEXPA14 gene in transgenic calli.

FIG. 5 shows the effect of transgenic callus on ginsenoside.

Detailed Description

The following detailed description of the application is provided in connection with the accompanying drawings that are presented to illustrate the application and not to limit the scope thereof. The examples provided below are intended as guidelines for further modifications by one of ordinary skill in the art and are not to be construed as limiting the application in any way.

The experimental methods in the following examples, unless otherwise specified, are conventional methods, and are carried out according to techniques or conditions described in the literature in the field or according to the product specifications. Materials, reagents and the like used in the examples described below are commercially available unless otherwise specified.

The quantitative experiments in the following examples were performed in triplicate unless otherwise indicated.

The departure vector pBWA (V) BS in the examples described below was purchased from Wohan remote biotechnology Co., ltd, cat# REC22D. The biological material is available to the public from the applicant and is only used for repeated experiments of the application and is not available for other uses.

American ginseng callus in the following examples was preserved by the present laboratory and has been described in: wang Tengteng, hu Jin, yuan Yuan, etc. BBM gene effects on American ginseng callus growth and ginsenoside content [ J ]. J.J.Chinese traditional medicine, 2023,48 (12): 3156-3161.DOI:10.19540. The biological material is available to the public from the applicant, and is only used for repeated experiments of the present application, but not as other uses.

The following examples were prepared using Excel 2021 to perform one-way analysis of variance with SPSS20.0 software, P < 0.05 (x) indicating significant differences, P < 0.01 (x) indicating significant differences, and P < 0.001 (x) indicating significant differences; analytical mapping was performed using Graphpad Prism 9.0.0 software.

Primer information used in the following examples is shown in Table 1 below.

TABLE 1 primer information used in the present application

EXAMPLE 1 cloning of the Gene encoding the American Ginseng protein PqEXPA14

1. Extraction of American ginseng total RNA

The total RNA of the root of the American ginseng is extracted by taking the wild American ginseng as a template according to a RNAprep pure Plant kit kit of Tiangen company.

2. Synthesis of first strand cDNA

The RNA was reverse transcribed using the cDNA synthesis kit (TranScript First-Strant cDNA Synthesis) from Beijing full gold Bio-company to obtain single-stranded cDNA.

3. Cloning of the PqEXPA14 Gene from American ginseng cDNA

The obtained single-stranded cDNA was PCR amplified using primer 1 and primer 2 (see Table 1 for specific sequences) to clone the full-length CDS sequence of the PqEXPA14 gene. UsingFastPfu Fly DNA Polymerase high-fidelity DNA polymerase performs PCR amplification.

The PqEXPA14 gene is SEQ ID No.2 in American ginseng coding sequence (CDS), and the coded amino acid sequence is the PqEXPA14 protein of SEQ ID No. 1. In the American ginseng genome DNA, the genome sequence of the encoding PqEXPA14 protein is shown as SEQ ID No.3 of a sequence table. The 365 th to 488 th exons of SEQ ID No.3, the 986 th to 1298 th exons, the second exons, and the 2054 th to 2357 th exons.

Example 2, dryThe scrambling vector pBWA (V) BS: pqEXPA14 _RNAi Construction and transformation of (C)

1. Interference vector pBWA (V) BS: pqEXPA14 _RNAi Construction of (3)

1) Designing 3 pairs of primers, and amplifying the primer pair cDAN of the primer 3 and the primer 4 to obtain a PCR product fragment with a sequence of SEQ ID No.5; amplifying Loop (DNA template) in the carrier kit by the primer 5 and the primer 6 to obtain a PCR product fragment with a sequence of SEQ ID No.6; primer 7 and primer 8 amplify cDAN to obtain PCR product fragment with SEQ ID No.7.

2) After electrophoresis of the PCR products with 1.2% agarose gel, 3 target bands were cut under an ultraviolet lamp and put into a system for sol recovery. DNA was recovered and purified by using HiPure Gel Pure DNA Mini Kit agarose gel DNA recovery kit according to the instructions.

3) The pBWA (V) BS vector and the recovered product were digested with BsaI enzyme, respectively. The vector enzyme digestion product and the recovered fragment enzyme digestion product are combined together and purified by a PCR purification kit, and the purified products are connected by using T4 ligase, and the vector diagram is shown in figure 1.

Transferring the ligation product obtained in the step 3 into competent cells of escherichia coli Trans1-T1 (Beijing full-scale gold biotechnology Co., ltd., product number CD 501-03), selecting positive colonies for sequencing, and extracting plasmids by using a TIANprep Rapid Mini Plasmid Kit plasmid extraction kit after sequencing is successful.

Interference vector pBWA (V) BS: pqEXPA14 _RNAi The structure of (2) is described as follows: a DNA fragment with a sequence of SEQ ID No.4 is inserted between restriction sites of restriction enzyme Bsa I of pBWA (V) BS vector, and other sequences of the pBWA (V) BS vector are kept unchanged to obtain the recombinant plasmid.

2. Interference vector pBWA (V) BS: pqEXPA14 _RNAi Vector transformation American ginseng callus

1) Culture of American ginseng callus: american ginseng callus culture conditions are 28 ℃, dark culture is carried out, and American ginseng callus MS culture medium is replaced every 14 days.

The formula of the culture medium is as follows:

american ginseng callus MS culture medium: MS+2, 4-D1 mg/L+KT0.25 mg/L+sucrose 30 g/L+agar 8g/L, pH 5.8.

American ginseng callus hypertonic medium: MS+2, 4-D1 mg/L+KT0.25 mg/L+sucrose 90 g/L+agar 8g/L, pH 5.8.

American ginseng screening culture medium: MS+2, 4-D1 mg/L+KT0.25 mg/L+sucrose 30 g/L+agar 8 g/L+glufosinate 5mg/L, pH 5.8.

2) Preparation of gold powder-DNA bullets: 30mg of gold powder is added with 75% ethanol, then vortex and centrifuge, after supernatant removal, 95% ethanol is added to resuspend the gold powder, and the process is repeated for 3 times. Cleaning with sterile water for three times, adding 500 μl sterilized glycerol, shaking by vortex for 5min to make gold powder suspension concentration 60mg/mL, packaging, and storing in-20deg.C refrigerator. Adding the prepared gold powder suspension into a sterilized 1.5mL centrifuge tube, and sequentially adding plasmid, sterile water and CaCl ₂ Spermidine, after mixing well, centrifuge at 12000rpm,4 ℃ for 5min, discard supernatant. Washing twice with absolute ethyl alcohol, adding corresponding absolute ethyl alcohol, and mixing uniformly by vortex to suspend the gold powder.

3) The gene gun bombards the callus: the callus after preculture on hypertonic medium was bombarded using a gene gun.

4) Screening and culturing after bombardment: transferring the callus after gene gun bombardment into a screening culture medium containing glufosinate (product number 20181127C1 of Buff (China) Co., ltd.) for culture, changing the culture medium every 14 days until the callus with glufosinate resistance grows out, and transferring the obtained resistant callus into MS culture medium for independent propagation culture.

The results are shown in FIG. 2: the callus which is not transferred into the plasmid vector gradually brown and dies due to the fact that the callus does not have glufosinate resistance, the transferred callus contains Bar genes to generate glufosinate resistance, and the transgenic callus with resistance is obtained after screening and culturing.

3. Contains pBWA (V) BS: pqEXPA14 _RNAi Positive callus molecule identification and transgenic callus gene expression analysis of vector

1) The Hi-DNAsecure Plant Kit plant genome extraction kit is used for extracting the plant genome obtained in the step 2The resulting DNA of glufosinate-resistant calli was expressed as pBWA (V) BS: pqEXPA14 _RNAi The plasmid was used as a positive control, wild callus and sterile water were used as negative controls, PCR amplification was performed using primer 9 and primer 10 (specific sequences are shown in Table 1), and the amplified products were separated by 1.5% agarose gel electrophoresis and analyzed by imaging using a gel imaging system.

Results display (fig. 3): the gene fragments of the band which is identical to the positive control in size of 491bp in the resistant callus are amplified as positive transgenic callus, and are respectively named RNAi1, RNAi2 and RNAi3.

2) Determining the expression level of the gene PqEXPA14 of the transgenic callus by using a real-time fluorescent quantitative PCR technology, using a primer 11 and a primer 12 (specific sequences are shown in Table 1), using cDNA of the transgenic callus as a template, using cDNA of the wild type American ginseng callus as a control, using a AceQ qPCR SYBR Green Master Mix (Low ROX Premixed) kit to perform real-time fluorescent quantitative PCR, adopting 2 ^-△△CT The results of the method are shown in FIG. 4.

Shown in fig. 4: the expression level of the PqEXPA14 genes of the transgenic calli RNAi1, RNAi2 and RNAi3 is obviously lower than that of the wild calli.

Example 3 analysis of ginsenoside content in transgenic callus

1. Sample solution preparation: freeze-drying callus, grinding into powder, weighing 0.1g, precisely weighing, adding 70% methanol 2mL, ultrasonically extracting at 25deg.C, centrifuging for 10min, centrifuging, collecting supernatant, filtering with 0.22 μm hydrophobic PTFE microporous filter head, and repeating for 3 times.

2. Preparation of a control solution: accurately weighing appropriate amounts of ginsenoside Rd, 20s-Rh respectively ₁ 、Rb ₁ 、Rg ₁ 、Rg ₂ 、Rf、Re、F ₁ The reference substances (Shanghai source leaf biotechnology Co., ltd., product numbers: Z09A9X67397, M11GB141261, G01O11Y126429, C27N11Q132589, P14O11L127486, P25F12L140073, J25O9A73424, 27J9X 64348) were dissolved in 70% methanol and shaken to a constant volume to prepare a 1G/L stock solution of the mixed reference substance. Taking a proper amount of stock solution, diluting with methanolThe mixed reference substance solutions with mass concentrations of 1, 7, 10, 70, 400, 700, 1000, 4000, 10000, 15000, 3000, 4000, 5000, 6000ng/L are prepared.

3. Q-TRAP-MS analysis conditions: chromatographic column: waters ACQUITY UPLC-T3 (2.1X100 mm,1.7 μm); mobile phase: 0.1% acetonitrile formate (a) -0.05% water formate (B); flow rate: 0.4mL min-1; sample injection amount: 1 μl; column temperature: the liquid chromatography gradient at 40℃is shown in Table 2. Mass spectrometry conditions: ion source Turbo V; ionization mode ESI-; the volume flow of the air curtain gas (CUR) is 30l/min; spray voltage (IS) 4500V; the volume flow of the atomized gas (GS 1) is 55L/min; the volume flow of the heating auxiliary gas (GS 2) is 55L/min; collecting MRM; ionization Temperature (TEMP) 550 ℃. The mass spectrum condition parameters are shown in table 3.

TABLE 2 gradient conditions for liquid chromatography

Time	A (0.1% formic acid-acetonitrile)	B (0.1% formic acid-water)
			0min	28％	72％
2.5min	31％	69％
			3.0min	35％	65％
4.5min	36％	64％
			6.0min	37％	63％
7.0min	50％	50％
			9.0min	98％	2％
11.0mi	98％	2％
			12.0mi	28％	72％
15.0mi	28％	72％

TABLE 3 UPLC-Q-TRAP-MS-MS mass spectrometry conditions

4. The data are collated by Excel 2021, and SPSS20.0 software is used for single-factor variance analysis; analytical mapping was performed using Graphpad Prism 9.0.0 software.

The results are shown in FIG. 5: RNAi interferes with callus ginsenoside Rd, 20s-Rh ₁ 、Rb ₁ 、Rg ₁ 、Rg ₂ 、Re、Rf、F ₁ The content is greatly increased compared with wild callus. Wherein RNAi1 interferes with callus ginsenoside Rd, 20s-Rh ₁ 、Rb ₁ 、Rg ₁ 、Rg ₂ 、Re、Rf、F ₁ The content of the ginsenoside Rd is obviously higher than that of wild callus, wherein Rd is increased by about 23.4 times, RNAi2 interferes with the callus, and the ginsenoside Rd and 20s-Rh are used for treating the callus ₁ 、Rb ₁ 、Rg ₁ 、F ₁ Rf content was significantly higher than wild-type calli, with Rd increased about 15.3-fold and Rh1 increased about 11.1-fold; RNAi3 interferes with callus ginsenoside Rd, 20s-Rh ₁ 、Rb ₁ 、Rg ₁ 、Rg ₂ 、Re、Rf、F ₁ The content is significantly higher than that of wild-type calli, with an increase in Rd of about 174.5-fold and Rb1 of about 67.3-fold.

The research proves that the Rd and 20s-Rh can be greatly improved by interfering the expression of the PqEXPA14 gene ₁ 、Rb ₁ 、Rg ₁ 、Rg ₂ 、Re、Rf、F ₁ The content of ginsenoside has important guiding significance and application value for subsequent research.

The present application is described in detail above. It will be apparent to those skilled in the art that the present application can be practiced in a wide range of equivalent parameters, concentrations, and conditions without departing from the spirit and scope of the application and without undue experimentation. While the application has been described with respect to specific embodiments, it will be appreciated that the application may be further modified. In general, this application is intended to cover any variations, uses, or adaptations of the application following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice within the art to which the application pertains.

Claims

1. A protein which is any one of the following:

a1 Protein with the amino acid sequence shown as SEQ ID No.1;

a2 Protein obtained by substituting and/or deleting and/or adding amino acid residues of the protein of A1) has more than 80% of identity with the protein shown in A1) and has the function of regulating and controlling the ginsenoside content of plant tissues;

2. The protein of claim 1, wherein: the protein is derived from American ginseng.

3. A biomaterial associated with the protein of claim 1 or 2, said biomaterial being any one of the following:

b1 A nucleic acid molecule encoding the protein of claim 1;

b2 An expression cassette comprising the nucleic acid molecule of B1);

c1 A nucleic acid molecule which inhibits or reduces or silences the expression of a gene encoding a protein as claimed in claim 1 or 2;

c2 Expression of the gene encoding the nucleic acid molecule of C1);

c3 An expression cassette containing the coding gene of C2);

4. A biomaterial according to claim 3, wherein: b1 The nucleic acid molecule is a gene as shown in E1) or E2) below:

e1 A cDNA molecule or a DNA molecule of SEQ ID No. 2;

5. The application is characterized in that: the application is any one of the following:

u1) use of the protein or the substance regulating gene expression or the substance regulating the activity or the content of the protein according to claim 1 or 2 for regulating the content of ginsenoside in plant tissues;

u2) use of the protein or the substance regulating gene expression or the substance regulating the activity or the content of the protein according to claim 1 or 2 for preparing a product regulating the ginsenoside content of plant tissues;

u3) use of the protein or the substance regulating gene expression or the substance regulating the activity or the content of the protein according to claim 1 or 2 for cultivating plants having altered ginsenoside content;

u4) use of the protein or the substance regulating the expression of the gene or the substance regulating the activity or the content of the protein according to claim 1 or 2 for producing a product for cultivating a plant having an increased ginsenoside content;

u5) use of a protein or a substance regulating the expression of a gene or a substance regulating the activity or content of said protein according to claim 1 or 2 in plant breeding.

6. The use according to claim 5, characterized in that: the substance for regulating the expression of a gene or the substance for regulating the activity or content of a protein is a biological material related to the protein, and the biological material is the biological material according to claim 3.

7. A method for regulating and controlling the ginsenoside content of plant tissues is characterized in that: comprises regulating the activity and/or content of the protein in claim 1 or 2 in the target plant, or/and regulating the expression level of the encoding gene of the protein in claim 1 or 2, so as to regulate the ginsenoside content in the plant tissue.

8. The method according to claim 7, wherein: the method for regulating the activity and/or content of the protein in the claim 1 or 2 in the target plant, or/and the expression level of the protein coding gene in the claim 1 or 2 comprises the steps of introducing a DNA molecule for inhibiting the protein coding gene into a receptor plant to obtain the target plant with higher ginsenoside content in plant tissues than the receptor plant; the coding gene encodes the protein of claim 1 or 2.

9. A method of growing a plant with an altered ginsenoside content in a plant tissue, comprising: 1) Inhibiting or reducing or silencing the expression level of the gene encoding the protein of claim 1 in a plant of interest, or/and inhibiting or reducing or silencing the activity and/or content of the gene encoding the protein of claim 1, to obtain a plant with an increased tissue ginsenoside content;

2) Increasing, enhancing and/or upregulating the expression level of a gene encoding a protein according to claim 1 in a plant of interest, or/and increasing, enhancing and/or upregulating the activity and/or content of a gene encoding a protein according to claim 1, to obtain a plant with a reduced tissue ginsenoside content.

10. Use according to claim 5 or 6, in accordance with the method according to any one of claims 7-9, characterized in that: the plant is any one of the following:

c1 Dicotyledonous plants;

c2 Plant of the order umbelliferae;

c3 Araliaceae plant;

c4 Ginseng plant;

c5 American ginseng).