Application of protein GbCET2 and coding gene thereof in regulating and controlling number of fruit branches of gossypium barbadense

Abstract

The invention discloses application of protein GbCET2 and a coding gene thereof in regulating and controlling the number of fruit branches of gossypium barbadense. The invention belongs to the field of botany, and particularly relates to application of protein GbCET2 and a coding gene thereof in regulating and controlling the number of fruit branches of gossypium barbadense. The protein GbCET2 or a substance for regulating and controlling the expression of a coding gene of the protein or a substance for regulating and controlling the activity or content of the protein can be applied to any one of the following aspects: 1) regulating and controlling the number of fruit branches of plants; the method comprises the following steps of (1) preparing GbCET2 in sea island cotton, (2) preparing a product for regulating and controlling the number of fruit branches of the plant, (3) cultivating the plant with the changed number of fruit branches, (4) preparing a product for cultivating the plant with the changed number of fruit branches, and (5) breeding the plant, and after the expression of GbCET2 is reduced in the sea island cotton by utilizing a virus-induced gene silencing technology, the number of the fruit branches of the sea island cotton is remarkably increased.

Description

Technical Field

[0001] This invention belongs to the field of botany, specifically relating to the application of the protein GbCET2 and its encoding gene in regulating the number of fruit branches in island cotton. Background Technology

[0002] Sea Island cotton, as a core germplasm of high-quality cotton, exhibits significantly superior fiber length, strength, and luster compared to upland cotton, making it an irreplaceable raw material for the high-end textile industry. However, the yield of Sea Island cotton is significantly lower than that of upland cotton. The number of fruiting branches is a crucial component of cotton yield, showing a highly significant positive correlation with the number of bolls per plant, thus influencing lint yield to a certain extent. Xinjiang is the only region in China where Sea Island cotton is cultivated, but its light and heat conditions dictate the cultivation of early-maturing, zero-fruiting-branch varieties. However, the compact plant type limits the development of bolls in the middle and lower parts of the plant. Appropriately increasing the number of fruiting branches can optimize the canopy structure and improve the allocation of dry matter to reproductive organs.

[0003] However, current research on the molecular regulatory mechanisms of fruit branch number in sea island cotton faces many bottlenecks, such as a lack of gene resources, unclear regulatory mechanisms, and a lack of functional markers for targeted breeding. This leads to traditional breeding relying on multiple generations of field phenotypic selection, which is inefficient. Therefore, discovering specific regulatory proteins and their encoding genes for fruit branch number in sea island cotton is of great significance for elucidating the molecular basis of plant architecture in sea island cotton and for breeding high-yielding sea island cotton varieties. Summary of the Invention

[0004] The technical problem to be solved by this invention is how to regulate the number of fruit branches in a plant.

[0005] To address the problems existing in the prior art, the present invention provides a method for changing the number of fruit branches in a plant, the method comprising the following steps M or P: Step M involves inhibiting, reducing, or silencing the activity and / or content of proteins in the target plant, or / and inhibiting, reducing, or silencing the expression level of the gene encoding the aforementioned proteins, to increase the number of fruiting branches in the plant; the plant with the increased number of fruiting branches has more fruiting branches than the target plant.

[0006] Step P is to enhance, increase, or upregulate the activity and / or content of proteins in the target plant, or / and enhance, increase, or upregulate the expression level of the encoding genes of the proteins mentioned above, in order to reduce the number of fruit branches in the plant; the plant with the reduced number of fruit branches has fewer fruit branches than the target plant.

[0007] The protein is any of the following proteins: a1) A protein with the amino acid sequence SEQ ID No:3; a2) A protein having the same function as the amino acid sequence shown in SEQ ID No:3, but with one or more amino acid residues substituted and / or deleted and / or added. Proteins that have more than 80% identity and the same function of any of the amino acid sequences defined in (a3), (a1), and (a2); The fusion protein is obtained by attaching a tag to the end of any of the proteins defined in (a4), (a1), (a3).

[0008] In the aforementioned proteins, the protein tag refers to a polypeptide or protein fused with the target protein using in vitro DNA recombination technology for expression, detection, tracing, and / or purification of the target protein. The protein tag may be a Flag tag, His tag, MBP tag, HA tag, myc tag, GST tag, and / or SUMO tag, etc.

[0009] In the above-mentioned proteins, identity refers to the identity of the amino acid sequences. The identity of amino acid sequences can be determined using homology search sites on the Internet, such as the BLAST page on the NCBI homepage. For example, in Advanced BLAST 2.1, using blastp as the program, setting the Expect value to 10, setting all filters to OFF, using BLOSUM62 as the matrix, setting the Gap existence cost, Per residue gap cost, and Lambda ratio to 11, 1, and 0.85 (default values) respectively, and performing an identity search on a pair of amino acid sequences to calculate the identity value (%), then the identity value can be obtained.

[0010] In the aforementioned proteins, the 80% or more identity can be at least 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 95%, 96%, 98%, 99%, or 100% identity.

[0011] Of the proteins mentioned above, SEQ ID No:3 consists of 174 amino acid residues. It is named the GbCET2 protein, and its encoding gene is [gene details missing]. GbCET2 Gene.

[0012] In this article, the protein is derived from sea island cotton ( Gossypium barbadense L.).

[0013] The protein is protein GbCET2, and the gene encoding protein GbCET2 is: GbCET2 In this article, the breeding objectives include cultivating plants with an increased number of fruiting branches; the breeding objectives also include cultivating plants with a decreased number of fruiting branches.

[0014] The present invention also provides a method for increasing the number of fruit branches in a plant, comprising inhibiting or reducing or silencing the expression level of the gene encoding the protein described above in the target plant, and / or the activity and / or content of the protein, thereby increasing the number of fruit branches in the plant.

[0015] In the above method, the inhibition, reduction, or silencing of the expression level and / or activity of the gene encoding the protein GbCET2 in the target plant can be achieved by using gene mutation, gene knockout, gene editing, or gene knockdown techniques to reduce or inactivate the activity of the gene encoding the protein GbCET2 in the genome of the target plant.

[0016] In one specific embodiment, inhibiting, reducing, or silencing the expression of the gene encoding the protein described above in the plant includes introducing the nucleic acid molecule, expression cassette, or recombinant vector described above into the target plant to obtain a plant with an increased number of fruiting branches.

[0017] The nucleic acid molecule that is inhibited, reduced, or silenced may be the DNA molecule shown in SEQ ID No:4.

[0018] As a specific embodiment, the recombinant vector is the recombinant vector pCLCrVA- GbCET2 The recombinant vector pCLCrVA- GbCET2 It is the sequence of the pCLCrVA vector (starting vector). Play I and Pac The fragments between the I recognition sites are replaced with the DNA molecule shown in SEQ ID No:4, while keeping the other nucleotides of the pCLCrVA vector (starting vector) unchanged to obtain the recombinant vector.

[0019] The present invention also provides the use of the protein described above, a substance regulating the expression of the gene encoding the protein, or a substance regulating the activity or content of the protein in any of the following: 1) Application in regulating the number of fruit-bearing branches in plants; 2) Application in the preparation of products that regulate the number of fruit-bearing branches in plants; 3) Application in cultivating plants with altered fruit branch numbers; 4) Application in the preparation of products from plants with altered fruit branch numbers; 5) Application in plant breeding.

[0020] In this article, the substance that regulates the activity and / or content of the protein may be a substance that regulates gene expression, wherein the gene encodes the protein GbCET2.

[0021] In the above text, the substance regulating gene expression can be a substance that performs at least one of the following six types of regulation: 1) regulation at the transcriptional level of the gene; 2) post-transcriptional regulation 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 mRNA transport of the gene from the nucleus to the cytoplasm); 4) regulation of translation of the gene; 5) regulation of mRNA degradation of the gene; and 6) post-translational regulation of the gene (i.e., regulation of the activity of the protein translated from the gene).

[0022] In this invention, the regulation can be upregulation, enhancement, or increase; the regulation can also be suppression, reduction, or silencing.

[0023] In this article, the enhancement, increase, or upregulation of the expression level of the coding gene of the aforementioned protein in the recipient plant, and / or the enhancement, increase, or upregulation of the activity and / or content of the coding gene of the aforementioned protein, is achieved by introducing the coding gene of the aforementioned protein into the recipient plant.

[0024] In this article, regulating the expression of the gene encoding the protein can be achieved by inhibiting, reducing, or silencing the expression of the gene. Inhibiting, reducing, or silencing the expression of the gene can be achieved through gene knockout or gene silencing.

[0025] Gene knockout refers to the phenomenon of inactivating a specific target gene through gene editing technology. Gene knockout inactivates a specific target gene by altering its DNA sequence, including but not limited to zinc-finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs), and the CRISPR / Cas system. CRISPR (clustered regulatory interspaced short palindromic repeat) is a site in the genome containing multiple short repeat sequences, where the Cas9 protein, mediated by RNA, can cleave target sequences recognized by crRNA–tracrRNA.

[0026] Gene silencing refers to the phenomenon of preventing or reducing gene expression without damaging the original DNA. Gene silencing presupposes no change in the DNA sequence, resulting in the absence or reduction of gene expression. Gene silencing can occur at two levels: transcriptional silencing due to DNA methylation, heterochromatinization, and position effects; and post-transcriptional gene silencing, which inactivates the gene at the post-transcriptional level through specific inhibition of target RNA. This includes antisense RNA, co-suppression, gene quelling, RNA interference (RNAi), and microRNA (miRNA)-mediated translational repression.

[0027] In the above applications, the substance that regulates the expression of the gene encoding the protein or the substance that regulates the activity or content of the protein can be a biological material related to the protein described above, and the biological material can be any of the following: c1) The nucleic acid molecule that encodes the protein described above; c2) An expression cassette containing the nucleic acid molecule described in c1); c3) A recombinant vector containing the nucleic acid molecule described in c1), or a recombinant vector containing the expression cassette described in c2); c4) Recombinant microorganisms containing the nucleic acid molecules described in c1), or recombinant microorganisms containing the expression cassette described in c2), or recombinant microorganisms containing the recombinant vector described in c3); c5) A transgenic plant cell line containing the nucleic acid molecule described in c1), or a transgenic plant cell line containing the expression cassette described in c2); c6) Transgenic plant tissue containing the nucleic acid molecules described in c1), or transgenic plant tissue containing the expression cassette described in c2); c7) A transgenic plant organ containing the nucleic acid molecule described in c1), or a transgenic plant organ containing the expression cassette described in c2); e1) Nucleic acid molecules that inhibit, reduce, or silence the expression of the protein-coding genes mentioned above; e2) An expression cassette containing the nucleic acid molecule described in e1); e3) A recombinant vector containing the nucleic acid molecule described in e1), or a recombinant vector containing the expression cassette described in e2); e4) Recombinant microorganisms containing the nucleic acid molecules described in e1), or recombinant microorganisms containing the expression cassette described in e2), or recombinant microorganisms containing the recombinant vector described in e3); e5) A transgenic plant cell line containing the nucleic acid molecule described in e1), or a transgenic plant cell line containing the expression cassette described in e2); e6) Transgenic plant tissue containing the nucleic acid molecules described in e1), or transgenic plant tissue containing the expression cassette described in e2); e7) A transgenic plant organ containing the nucleic acid molecule described in e1) or a transgenic plant organ containing the expression cassette described in e2).

[0028] In the above applications, c1) the nucleic acid molecule can be any of the following DNA molecules: d1) The nucleotide sequence is the DNA molecule shown in SEQ ID No:2; d2) The coding sequence is the DNA molecule shown in SEQ ID No:1; d3) has 90% or more identity with the nucleotide sequence defined by d1) or d2) and encodes a DNA molecule that encodes the protein described above; d4) A DNA molecule that hybridizes under strict conditions with a nucleotide sequence defined by d1) or d2) and encodes the protein described above.

[0029] In the above applications, the nucleic acid molecule mentioned in e1) is as follows: d1) The DNA molecule shown in SEQ ID No:4.

[0030] d2) DNA molecules that have 90% or more identity with the nucleotide sequence defined by d1); d3) DNA molecules that hybridize with nucleotide sequences defined by d1) or d2) under strict conditions.

[0031] The nucleic acid molecules mentioned in this article can be DNA, such as cDNA, genomic DNA, or recombinant DNA; the nucleic acid molecules can also be RNA, such as gRNA, mRNA, siRNA, shRNA, sgRNA, miRNA, or antisense RNA.

[0032] The vectors described herein are known to those skilled in the art and include, but are not limited to: plasmids, bacteriophages (such as λ phage or M13 filamentous phage), granules (i.e., Cos plasmids), Ti plasmids, or viral vectors.

[0033] Existing plant expression vectors can be used to construct structures containing... GbCET2 Recombinant gene expression vectors. These plant expression vectors include, but are not limited to, binary Agrobacterium vectors and vectors suitable for plant microbombardment. The plant expression vectors may also contain the 3' untranslated region of the exogenous gene, i.e., containing a polyadenylate signal and any other DNA fragment involved in mRNA processing or gene expression. The polyadenylate signal can guide the addition of polyadenylate to the 3' end of the mRNA precursor; similar functions exist for the untranslated regions transcribed at the 3' end of genes including, but not limited to, Agrobacterium crown gall-inducing (Ti) plasmid genes (such as the Nos gene for lipase synthesis) and plant genes (such as the soybean storage protein gene).

[0034] use GbCET2 When constructing recombinant plant expression vectors, any type of enhancing promoter or constitutive promoter can be added before the transcription initiation nucleotide, including but not limited to the cauliflower mosaic virus (CAMV) 35S promoter and the maize ubiquitin promoter. These can be used alone or in combination with other plant promoters. Furthermore, when constructing plant expression vectors using the genes of this invention, enhancers, including translational enhancers or transcriptional enhancers, can also be used. These enhancer regions can be ATG start codons or adjacent region start codons, but they must be identical to the reading frame of the coding sequence to ensure correct translation of the entire sequence. The sources of the translation control signals and start codons are wide-ranging; they can be natural or synthetic. The translation initiation region can originate from the transcription initiation region or structural genes.

[0035] As a specific embodiment, e3) the recombinant vector can be the recombinant vector pCLCrVA- GbCET2 The recombinant vector pCLCrVA- GbCET2 It is the sequence of the pCLCrVA vector (starting vector). Play I and Pac The fragments between the I recognition sites are replaced with the DNA molecule shown in SEQ ID No:4, while keeping the other nucleotides of the pCLCrVA vector (starting vector) unchanged to obtain the recombinant vector.

[0036] In the above applications or methods, the plant is any one of the following: N1) Dicotyledons; N2) Malvales (Malva orders) N3) Malvaceae family plants; N4) Plants of the genus *Gossypium*; N5) Cotton.

[0037] The cotton mentioned above may be Sea Island cotton (…). Gossypium barbadense L.).

[0038] This invention identified a gene from sea island cotton. GbCET2 In genes GbCET2 The coding region contains a SNP site (Gbar_D07_15803388) that is highly associated with the number of fruiting branches; this variation affects the amino acid sequence of the functional domain of the protein encoded by this gene. Virus-induced gene silencing (VIGS) technology was used to reduce [the number of fruiting branches] in Sea Island cotton. GbCET2 After expression, the number of fruiting branches increased dramatically. This gene encodes a phosphatidylethanolamine-binding protein, a novel protein that regulates the number of fruiting branches in sea-island cotton, which is of great significance for promoting high-yield breeding applications of sea-island cotton. Attached Figure Description

[0039] Figure 1 for GbCET2 Gene coding region sequence and protein sequence analysis. 'a' represents two different haplotypes. GbCET2 The coding region sequence of a gene. Gray lines indicate exons, and black lines indicate introns. b represents a key amino acid variation. GbCET2 Location within the protein's functional domains. Marked with a black box. GbCET2 The protein's functional domain is the phosphatidylethanolamine-binding protein (PBP) domain. The 113th amino acid (P / S) encoded by the key non-synonymous SNP (Gbar_D07_15803388, C / T) is located precisely within the PBP domain.

[0040] Figure 2 To detect VIGS in Sea Island cotton using qRT-PCR GbCET2 A bar chart representing the levels. WT, pCLCrVA, and pCLCrVA- GbCET2 These represent wild-type control of sea island cotton, VIGS empty control, and VIGS silenced control, respectively. GbCET2 Positive single plants.

[0041] Figure 3 To utilize VIGS silence GbCET2 The number of fruiting branches in the subsequent Sea Island cotton. WT, pCLCrVA and pCLCrVA- GbCET2 These represent wild-type control of sea island cotton, VIGS empty control, and VIGS silenced control, respectively. GbCET2 Positive single plants. Detailed Implementation

[0042] The present invention will now be described in further detail with reference to specific embodiments. The given embodiments are merely illustrative of the invention and not intended to limit its scope. The embodiments provided below can serve as a guide for further improvements by those skilled in the art and do not constitute a limitation on the invention in any way.

[0043] Unless otherwise specified, the experimental methods used in the following examples are conventional methods, performed according to the techniques or conditions described in the literature in this field or according to the product instructions. Unless otherwise specified, the materials and reagents used in the following examples are commercially available.

[0044] Unless otherwise specified, the quantitative experiments in the following examples are all repeated three times, and the results are averaged.

[0045] The pCLCrVA plasmid used in the following examples is described in: Zhao N, et al. Genomic and GWASanalyses demonstrate phylogenomic relationships of Gossypium barbadense inChina and selection for fiber length, lint percentage and Fusarium wilt resistance. Plant Biotechnol J. 2022;20(4):691-710. The biological material is available to the public from the applicant and is intended solely for the purpose of repeating experiments of this invention and may not be used for any other purpose.

[0046] The sea island cotton in the following examples is described in: Zhao N, et al. Genomic and GWAS analyses demonstrate phylogenomic relationships of Gossypium barbadense in China and selection for fiber length, lint percentage and Fusarium wilt resistance. Plant Biotechnol J. 2022;20(4):691-710. The biological material is available to the public from the applicant and is intended solely for the purpose of replicating experiments of this invention and may not be used for any other purpose.

[0047] The following examples used IBM SPSS_Statistics_25 statistical software to process the data. The experimental results are expressed as mean values. T-test was used. * indicates that the difference is statistically significant (P < 0.05), ** indicates that the difference is highly statistically significant (P < 0.01), and *** indicates that the difference is extremely statistically significant (P < 0.001).

[0048] Example 1: Obtaining genes regulating the number of fruit branches in sea island cotton GbCET2 The genes are derived from Sea Island cotton. GbCET2 The gene coding sequence (CDS) is SEQ ID No:1, the genome coding strand sequence is SEQ ID No:2, the encoded protein is named GbCET2 protein or protein GbCET2, and the amino acid sequence of the encoded protein is shown in SEQ ID No:3.

[0049] The SNP (Gbar_D07_15803388) that is highly significantly associated with the number of fruiting branches in sea island cotton is located in the gene GbCET2 Within the encoding area ( Figure 1 (a) Specifically located at position 337 of SEQ ID No:1, its amino acid encoding position 113 of the GbCET2 protein (SEQ ID No:3) is located precisely within the functional domain of the GbCET2 protein—the phosphatidylethanolamine-binding protein (PBP) domain. Figure 1 (b) When GbCET2 When position 337 of the gene's coding sequence (SEQ ID No:1) is C, position 113 of the encoded GbCET2 protein's amino acid sequence (SEQ ID No:3) is proline (Pro, abbreviated as P); studies have found that when GbCET2 When the coding sequence of the gene (SEQ ID No:1) is T at position 337, the amino acid sequence of the encoded GbCET2 protein (SEQ ID No:3) is serine (S, abbreviated as S) at position 113. It is speculated that the protein GbCET2 and its encoding gene are significantly correlated with the number of fruit branches in sea island cotton.

[0050] Example 2, VIGS Silence GbCET2 Impact on the number of fruiting branches of sea island cotton 1. Silence GbCET2 Construction of VIGS recombinant vector and acquisition of recombinant strains According to genes GbCET2 The coding sequence was used to design primers for VIGS vector construction. A 5' extension was added to the 5' end of the forward primer F. Play The I restriction enzyme site (ACTAGT) is specifically defined in the forward primer F as: 5'-GTTGGGGAGAGTGATTGGGG-3'; the reverse primer R has an additional restriction enzyme at its 5' end. Pac The I restriction site (TTAATTAA) has a specific reverse primer nucleotide sequence of 5'-GCGTCTTCTAGCAGCTGTTTC-3'.

[0051] Recombinant plasmid pCLCrVA- GbCET2 The structure is described as follows: To deliver the pCLCrVA vector sequence Play I and Pac The fragments between the I recognition sites were replaced with the DNA molecule shown in SEQ ID No:4, while keeping the other nucleotides of the pCLCrVA vector unchanged to obtain the recombinant vector.

[0052] Recombinant vector pCLCrVA- GbCET2After successful construction, the bacteria were heat-shocked and transferred into Agrobacterium EHA105 strain (Sangon Biotech Co., Ltd., catalog number B528432) to obtain a strain containing pCLCrVA- GbCET2 The plasmid of Agrobacterium EHA105 was named Agrobacterium tumefaciens EHA105 / pCLCrVA- GbCET2 .

[0053] The empty vector pCLCrVA was heat-shocked into Agrobacterium EHA105 strain to obtain EHA105 / pCLCrVA as an empty vector control.

[0054] The vector pCLCrVB was heat-shocked into Agrobacterium EHA105 strain to obtain EHA105 / pCLCrVB. Before transformation, it was reacted with EHA105 / pCLCrVB- GbCET2 Equal volumes of Agrobacterium tumefaciens culture of EHA105 / pCLCrVA were mixed.

[0055] 2. GbCET2 Obtaining Silent Island Cotton Plants and Identifying the Number of Fruiting Branches Island cotton was grown using soil cultivation as the transgenic recipient. Two weeks later, the cotyledons were fully expanded, and genetic transformation was carried out.

[0056] Take the strain EHA105 / pCLCrVA- obtained in step 1 GbCET2 EHA105 / pCLCrVA and EHA105 / pCLCrVB were cultured at 28℃ to the logarithmic growth phase; the cells were collected by centrifugation at 8000 rpm for 5 min, and then resuspended in VIGS infection solution (10 mM MMES, 200 µM AS, 10 mM MgCl2), and the bacterial concentration was adjusted to OD200. 600 =Approximately 1.0; EHA105 / pCLCrVA- GbCET2 EHA105 / pCLCrVA and EHA105 / pCLCrVB bacterial solutions were mixed at a volume ratio of 1:1 and allowed to stand at room temperature for 3 hours before being used to transform cotton leaves. The mixed bacterial solution of EHA105 / pCLCrVA and EHA105 / pCLCrVB served as an empty control.

[0057] Using a 1 mL sterile syringe, aspirate the bacterial suspension. First, make a tiny, non-penetrating incision on the underside of the cotyledon with a needle, then inject the inoculated plant using a needleless syringe. Injected sea island cotton plants were placed in a 28℃ greenhouse and cultured under a 16 h / 8 h light-dark cycle. The experiment was repeated three times, with 20 plants of each line planted each time.

[0058] Two weeks later, wild-type control (WT), VIGS empty control (pCLCrVA), and VIGS silent control of Sea Island cotton were collected. GbCET2Single plant (pCLCrVA-) GbCET2 RNA was extracted from leaf samples, reverse transcribed into cDNA, and then the gene was detected using Real-time PCR. GbCET2 The silencing efficiency (forward primer 5'-ATATCCCCGGCACAACAGATGC-3'; reverse primer 5'-CACTGTTTGCCTGCCTTTTTGC-3').

[0059] The results showed that after VIGS treatment, pCLCrVA- GbCET2 In the plant GbCET2 The transcriptional expression level was significantly reduced ( Figure 2 ); GbCET2 The number of fruiting branches on silent island cotton plants (average 12) was significantly increased compared to the control plants (average 11), and by one more fruiting branch compared to both the wild type and the VIGS empty control. Figure 3 This confirms that GbCET2 It negatively regulates the number of fruiting branches in island cotton.

[0060] The present invention has been described in detail above. Those skilled in the art will recognize that the invention can be practiced in a wide range of ways with equivalent parameters, concentrations, and conditions without departing from its spirit and scope, and without requiring unnecessary experiments. While specific embodiments have been provided, it should be understood that further modifications can be made to the invention. In summary, according to the principles of the invention, this application is intended to include any changes, uses, or improvements to the invention, including changes made using conventional techniques known in the art that depart from the scope disclosed herein.

Claims

1. A method for changing the number of fruit-bearing branches in a plant, characterized in that: The method includes step M or P, wherein step M is to inhibit or reduce or silence the activity and / or content of a protein in the target plant, or / and to inhibit or reduce or silence the expression level of the gene encoding the protein, in order to increase the number of fruit branches in the plant. The method includes step P, which is to enhance, increase or upregulate the activity and / or content of proteins in the target plant, or / and enhance, increase or upregulate the expression level of the gene encoding the protein, so as to reduce the number of fruit branches in the plant. The protein is any of the following proteins: a1) A protein with the amino acid sequence SEQ ID No:3; a2) A protein having the same function as the amino acid sequence shown in SEQ ID No:3, but with one or more amino acid residues substituted and / or deleted and / or added. a3) Proteins that share more than 80% identity with the amino acid sequence defined by a1) or a2) and have the same function; a4) A fusion protein obtained by attaching a tag to the end of any of the proteins defined in a1)-a3).

2. A method for cultivating plants with an increased number of fruiting branches, characterized in that, This includes inhibiting, reducing, or silencing the expression level of the gene encoding the protein of claim 1 in the target plant, and / or, the activity and / or content of the protein, resulting in a plant with an increased number of fruiting branches, wherein the plant with the increased number of fruiting branches has more fruiting branches than the target plant.

3. The method according to claim 1 or 2, characterized in that, The inhibition, reduction, or silencing of the expression of the gene encoding the protein of claim 1 in the plant comprises introducing the gene encoding the protein of claim 1 into the target plant to inhibit, reduce, or silence the expression of the protein of claim 1, thereby obtaining a plant with an increased number of fruiting branches.

4. A method for cultivating plants with a reduced number of fruiting branches, characterized in that, This includes enhancing, increasing, or upregulating the expression level of the gene encoding the protein described in claim 1 in the target plant, and / or, the activity and / or content of the protein, to obtain a plant with fewer fruit branches, wherein the plant with fewer fruit branches has fewer fruit branches than the target plant.

5. The method according to any one of claims 1-4, characterized in that, The protein is derived from cotton.

6. The use of the protein of claim 1 or the substance that regulates the expression of the gene encoding the protein, or the substance that regulates the activity or content of the protein, in any of the following: 1) Application in regulating the number of fruit-bearing branches in plants; 2) Application in the preparation of products that regulate the number of fruit-bearing branches in plants; 3) Application in cultivating plants with altered fruit branch numbers; 4) Application in the preparation of products from plants with altered fruit branch numbers; 5) Applications in plant breeding; The purpose of the breeding includes cultivating plant varieties with an increased number of fruiting branches; the purpose of the breeding also includes cultivating plant varieties with a decreased number of fruiting branches.

7. The application according to claim 6, characterized in that, The substance regulating the expression of the gene encoding the protein, or the substance regulating the activity or content of the protein, is a biological material related to the protein in the method of claim 1, wherein the biological material is any one of the following: c1) The nucleic acid molecule encoding the protein; c2) An expression cassette containing the nucleic acid molecule described in c1); c3) A recombinant vector containing the nucleic acid molecule described in c1), or a recombinant vector containing the expression cassette described in c2); c4) Recombinant microorganisms containing the nucleic acid molecules described in c1), or recombinant microorganisms containing the expression cassette described in c2), or recombinant microorganisms containing the recombinant vector described in c3); c5) A transgenic plant cell line containing the nucleic acid molecule described in c1), or a transgenic plant cell line containing the expression cassette described in c2); c6) Transgenic plant tissue containing the nucleic acid molecules described in c1), or transgenic plant tissue containing the expression cassette described in c2); c7) A transgenic plant organ containing the nucleic acid molecule described in c1), or a transgenic plant organ containing the expression cassette described in c2); e1) Nucleic acid molecules that inhibit, reduce, or silence the expression of the protein-encoding gene; e2) An expression cassette containing the nucleic acid molecule described in e1); e3) A recombinant vector containing the nucleic acid molecule described in e1), or a recombinant vector containing the expression cassette described in e2); e4) Recombinant microorganisms containing the nucleic acid molecules described in e1), or recombinant microorganisms containing the expression cassette described in e2), or recombinant microorganisms containing the recombinant vector described in e3); e5) A transgenic plant cell line containing the nucleic acid molecule described in e1), or a transgenic plant cell line containing the expression cassette described in e2); e6) Transgenic plant tissue containing the nucleic acid molecules described in e1), or transgenic plant tissue containing the expression cassette described in e2); e7) A transgenic plant organ containing the nucleic acid molecule described in e1) or a transgenic plant organ containing the expression cassette described in e2).

8. The application according to claim 3, characterized in that: e1) The nucleic acid molecule is as follows: d1) The DNA molecule shown in SEQ ID No:4; d2) DNA molecules that have 90% or more identity with the nucleotide sequence defined by d1); d3) DNA molecules that hybridize with nucleotide sequences defined by d1) or d2) under strict conditions.

9. The protein as described in claim 1 or 2 and / or the biomaterial as described in claim 7 or 8.

10. The method according to any one of claims 1-4, characterized in that, The plant is any one of the following: N1) Dicotyledons; N2) Malvales (Malva orders) N3) Malvaceae family plants; N4) Plants of the genus *Gossypium*; N5) Cotton.

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