Application of rice OsC3HC4 protein and coding gene thereof in regulation and control of high temperature resistance of rice

Abstract

The invention discloses application of rice OsC3HC4 protein and a coding gene thereof in regulating and controlling high temperature resistance of rice. The invention belongs to the field of plant breeding, and particularly relates to application of rice OsC3HC4 protein and a coding gene thereof to regulation and control of high temperature resistance of rice. The protein or the substance for regulating and controlling the activity or content of the protein or regulating and controlling the expression of the coding gene of the protein can be applied to the following aspects: 1) regulating and controlling the high-temperature resistance of plants; 2) preparing a product for regulating and controlling the high temperature resistance of plants; 3) cultivating plants with high-temperature resistance change; 4) preparing a product for cultivating the plant with the high temperature resistance changed; and 5) plant breeding. After the coding gene of the OsC3HC4 protein is subjected to CRISPR gene editing and knockout, an OsC3HC4 knockout mutant after high-temperature stress treatment has a high-temperature-resistant phenotype, which indicates that the OsC3HC4 gene plays an important role in regulating and controlling the high-temperature resistance of rice.

Description

Technical Field

[0001] The invention belongs to the field of plant breeding, and in particular relates to application of rice OsC3HC4 protein and its encoding gene in regulating the high temperature resistance of rice. Background Art

[0002] High temperature stress caused by global warming seriously threatens global food security. Rice is an important food crop that feeds more than half of the world's population, and high temperature stress can seriously reduce rice yield and quality. Extreme temperature impacts global extreme climate changes have put crops at risk of reduced yields. For rice, the impact of high temperature stress on its reproductive growth period is far greater than that on its vegetative growth period, and the flowering period is the most sensitive period to high temperature stress. Research on rice heat tolerance under global climate change, especially the discovery of high temperature stress-related resistance genes and their characteristics and functions, and the cultivation of excellent heat-resistant varieties, has become a global topic in rice genetic breeding research, which has far-reaching significance for promoting sustainable rice production and world food production security. Summary of the invention

[0003] The main problem to be solved by the present invention is how to improve the high temperature resistance of plants.

[0004] In order to solve the above problems, the present invention provides the use of protein or a substance that regulates the activity or content of the protein or regulates the expression of a gene encoding the protein in regulating the high temperature resistance of plants.

[0005] The use of the protein or gene expression regulating substance provided by the present invention or the substance regulating the activity or content of the protein in any of the following:

[0006] 1) Application in regulating plant's ability to tolerate high temperatures;

[0007] 2) Application in the preparation of products for regulating the high temperature tolerance of plants;

[0008] 3) Application in breeding plants with altered high temperature tolerance;

[0009] 4) Application in the preparation of products for cultivating plants with altered high temperature tolerance;

[0010] 5) Application in plant breeding;

[0011] The protein is any of the following:

[0012] a1) a protein having an amino acid sequence of SEQ ID No: 1;

[0013] a2) a protein having the same function as the amino acid sequence shown in SEQ ID No: 1 after one or more amino acid residues are substituted and / or deleted and / or added;

[0014] a3) a protein having an amino acid sequence of at least 75% identity with any of a1) or (a2) and having the same function;

[0015] a4) A fusion protein obtained by connecting a tag to the end of the protein defined in any one of a1) to (a3).

[0016] The name of the protein described in a1) above is OsC3HC4.

[0017] In order to facilitate purification or detection of the protein in a1), a tag protein may be connected to the amino terminus or carboxyl terminus of the protein consisting of the amino acid sequence shown in SEQ ID No: 1 in the sequence listing.

[0018] The tag protein includes but is not limited to: GST (glutathione sulfhydryltransferase) 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), eCFP (enhanced cyan fluorescent protein), eYFP (enhanced yellow-green fluorescent protein), mCherry (monomeric red fluorescent protein) or AviTag tag protein.

[0019] The above proteins can be artificially synthesized, or their encoding genes can be synthesized first and then expressed biologically.

[0020] Those skilled in the art can easily mutate the nucleotide sequence encoding the protein OsC3HC4 of the present invention by using known methods, such as directed evolution or point mutation. Those artificially modified nucleotides having 75% or more identity with the nucleotide sequence of the protein OsC3HC4 isolated by the present invention are derived from the nucleotide sequence of the present invention and are equivalent to the sequence of the present invention as long as they encode the protein OsC3HC4 and have the function of the protein OsC3HC4.

[0021] The aforementioned 75% or more identity may be 80%, 85%, 90% or 95% or more identity.

[0022] Herein, identity refers to the identity of an amino acid sequence or a nucleotide sequence. The identity of an amino acid sequence or a nucleotide sequence can be determined using a homology search site on the Internet, such as the BLAST webpage on the NCBI homepage website. For example, in Advanced BLAST2.1, by using blastp as a program, setting the Expect value to 10, setting all Filters to OFF, using BLOSUM62 as a Matrix, setting Gap existence cost, Per residue gap cost and Lambda ratio to 11, 1 and 0.85 (default values) respectively and searching for a pair of amino acid sequences or nucleotide sequences to calculate the identity, then the value (%) of the identity can be obtained.

[0023] Herein, the 80% or greater identity 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.

[0024] Herein, the 90% or greater identity may be at least 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98% or 99% identity.

[0025] In the above application, the protein is derived from rice (Oryza sativa L.).

[0026] Herein, the substance that regulates the activity and / or content of the protein may be a substance that regulates the expression of a gene that encodes the protein OsC3HC4.

[0027] In the present invention, the regulation may be up-regulation, enhancement or increase. The regulation may also be inhibition, reduction or down-regulation.

[0028] Herein, the upregulation or enhancement or increase of the expression level of the gene encoding the protein mentioned above in the recipient plant, or / and the enhancement, improvement or upregulation of the activity and / or content of the gene encoding the above protein is achieved by introducing the gene encoding the above protein into the recipient plant.

[0029] Herein, regulating the expression of the coding gene of the protein may also be inhibiting, reducing or down-regulating the expression of the coding gene. Inhibiting, reducing or down-regulating the expression of the coding gene may be achieved by gene knockout or gene silencing.

[0030] In the above application, the substance regulating the expression of the gene or the substance regulating the activity or content of the protein may be a biological material related to the protein mentioned above, and the biological material may be any of the following:

[0031] c1) a nucleic acid molecule encoding the protein described above;

[0032] c2) an expression cassette containing the nucleic acid molecule described in c1);

[0033] c3) a recombinant vector containing the nucleic acid molecule described in c1), or a recombinant vector containing the expression cassette described in c2);

[0034] c4) a recombinant microorganism containing the nucleic acid molecule described in c1), or a recombinant microorganism containing the expression cassette described in c2), or a recombinant microorganism containing the recombinant vector described in c3);

[0035] 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);

[0036] c6) transgenic plant tissue containing the nucleic acid molecule described in c1), or transgenic plant tissue containing the expression cassette described in c2);

[0037] 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);

[0038] In the above application, the nucleic acid molecule described in c1) can be any of the following DNA molecules,

[0039] d1) the nucleotide sequence is a DNA molecule shown in SEQ ID No: 3;

[0040] d2) the coding region sequence is the DNA molecule shown in SEQ ID No: 2 in the sequence listing;

[0041] d3) a DNA molecule that has 90% or more identity with the nucleotide sequence defined in d1) or d2) and encodes the protein described above;

[0042] d4) A DNA molecule that hybridizes with the nucleotide sequence defined in d1) or d2) under stringent conditions and encodes the protein described above.

[0043] The nucleic acid molecule described herein can be DNA, such as cDNA, genomic DNA or recombinant DNA; the nucleic acid molecule can also be RNA, such as gRNA, mRNA, siRNA, shRNA, sgRNA, miRNA or antisense RNA.

[0044] The vectors described herein are well known to those skilled in the art, including but not limited to: plasmid, phage (such as lambda phage or M13 filamentous phage, etc.), cosmid (ie, cosmid), Ti plasmid or viral vector.

[0045] The present invention also provides a method for improving the high temperature resistance of plants, the method comprising step P, wherein step P is to inhibit or reduce or silence the activity and / or content of the protein mentioned above in the receptor plant, or / and, inhibit or reduce or silence the expression level of the gene encoding the protein mentioned above, so as to improve the high temperature resistance of the plant.

[0046] In the above method, the inhibition, reduction or silencing of the expression level and / or activity of the gene encoding the protein OsC3HC4 in the recipient plant can be: using gene mutation, gene knockout, gene editing or gene knockdown technology to reduce or inactivate the activity of the gene encoding the protein OsC3HC4 in the genome of the recipient plant.

[0047] The present invention also provides a method for reducing the high temperature resistance of plants, the method comprising step M, wherein step M is to enhance, increase or up-regulate the activity and / or content of the protein mentioned above in the recipient plant, or / and, enhance, increase or up-regulate the expression level of the gene encoding the protein mentioned above, so as to reduce the high temperature resistance of the plant.

[0048] The present invention provides a method for cultivating plants with enhanced high temperature resistance, comprising inhibiting or reducing or silencing the expression of the coding gene of the above-mentioned protein and / or the content and / or activity of the above-mentioned protein in a receptor plant, or / and inhibiting or reducing or silencing the activity and / or content of the coding gene of the above-mentioned protein, so as to obtain plants with enhanced high temperature resistance.

[0049] In the present invention, the purpose of plant breeding may include cultivating plants with enhanced high temperature resistance.

[0050] In the above method, the inhibition, reduction or silencing of the expression level and / or activity of the gene encoding the protein OsC3HC4 in the recipient plant can be: using gene mutation, gene knockout, gene editing or gene knockdown technology to reduce or inactivate the activity of the gene encoding the protein OsC3HC4 in the genome of the recipient plant.

[0051] In the above method, the gene knockout is achieved by the CRISPR / Cas9 system.

[0052] In the above method, the target of gene editing by the CRISPR / Cas9 system is positions 5404-5423 of sequence 3.

[0053] In the above method, the knockout of the coding gene of the protein in the target rice may be to perform at least one of the following mutations on the protein in sequence 1 in the rice genome:

[0054] 1) replacing 5'-CCTCTCCCCATAGTAGAATA-3' in the protein encoding gene in rice genomic DNA with 5'-CCTCTCCATAGTAGAATA-3', thereby knocking out the gene encoding OsC3HC4 protein;

[0055] 2) Replacing 5'-CCTCTCCCCATAGTAGAATA-3' in the gene encoding the protein in rice genomic DNA with 5'-CCTCTCCCCCATAGTAGAATA-3', thereby knocking out the gene encoding the OsC3HC4 protein.

[0056] Herein, the high temperature treatment condition may be: treating three-week-old rice seedlings at 45°C for 36 hours.

[0057] In the above application or method, the plant is any one of the following:

[0058] N1) monocots or dicots;

[0059] N2) Gramineae;

[0060] N3) Gramineae;

[0061] N4) Oryza plants;

[0062] N5) Rice.

[0063] Herein, the plant's ability to tolerate high temperatures may include a plant's phenotype of tolerance to high temperature stress and an increased survival rate.

[0064] In the present invention, the enhanced high temperature tolerance is specifically manifested as follows: when three-week-old seedlings are subjected to high temperature stress of 45°C for 36 hours, the survival rate of knockout mutant plants is significantly improved compared with that of control plants.

[0065] The present invention utilizes CRISPR / Cas9-mediated gene editing technology to knock out specific targets of the coding gene for the rice heat-resistance-related protein OsC3HC4, providing new materials for the breeding of heat-resistant rice varieties, and playing a positive role in accelerating the improvement of rice varieties. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] Figure 1 Schematic diagram of the structure of recombinant plasmid SG2027-OsC3HC4.

[0067] Figure 2 The nucleotide sequence of the mutation site and its surrounding nucleotides.

[0068] Figure 3The phenotypes and statistical graphs of rice under high temperature stress. A is the phenotype graph of 93-11 and osC3HC4 mutants osc3hc4-1 and osc3hc4-2 under normal growth conditions; B is the phenotype and survival rate statistical graph of 93-11 and osC3HC4 mutants osc3hc4-1 and osc3hc4-2 under high temperature stress conditions. DETAILED DESCRIPTION

[0069] The present invention is further described in detail below in conjunction with specific embodiments, and the examples provided are only for illustrating the present invention, rather than for limiting the scope of the present invention. The examples provided below can be used as a guide for further improvements by those of ordinary skill in the art, and do not constitute a limitation of the present invention in any way.

[0070] The experimental methods in the following examples, unless otherwise specified, are all conventional methods, and are performed according to the techniques or conditions described in the literature in the field or according to the product instructions. The materials, reagents, etc. used in the following examples, unless otherwise specified, can all be obtained from commercial channels.

[0071] Unless otherwise specified, the quantitative tests in the following examples were performed three times and the results were averaged.

[0072] The SG2027 vector in the following embodiment has been recorded in: Zhang Q, Liang Z, Cui X, et al. N6-methyladenine DNA methylation in Japonica and Indica rice genomes and its association with gene expression, plant development, and stress responses. Molecular Plant, 2018, 11(12): 1492-1508. The public can obtain the biological material from the applicant. The biological material is only used for repeating the relevant experiments of the present invention and cannot be used for other purposes.

[0073] The rice variety 93-11 and rice variety NIP in the following examples have been recorded in: Zhang Q, Liang Z, Cui X, et al. N6-methyladenine DNA methylation in Japonica and Indica rice genomes and its association with gene expression, plant development, and stress responses. Molecular Plant, 2018, 11(12): 1492-1508. The public can obtain the biological material from the applicant. The biological material is only used for repeating the experiments of the present invention and cannot be used for other purposes.

[0074] The following examples use EXCEL software to perform statistical analysis of data, and SPASS software to perform multiple difference comparisons of data.

[0075] Example 1. Creation of OSC3HC4 gene knockout rice

[0076] 1. Obtaining the rice OSC3HC4 gene

[0077] DNA from the leaves of rice variety 93-11 was extracted and used as a template. Primers OSC3HC4-F: 5'-ATGCAGCCCGCCCCC-3'; OSC3HC4-R: 5'-TCATGGCGTGATGGC-3' were used to generate the primers. Max Super-Fidelity DNA Polymerase (Cat. No.: P505-d1, Vazyme) was used for PCR amplification to obtain the amplified product, i.e., the genomic sequence of the OSC3HC4 gene. In the genomic DNA of rice 93-11, the genomic gene nucleotide sequence encoding the OsC3HC4 protein is SEQ ID No: 3. The 201st to 508th positions of SEQ ID No: 3 are the first exon, the 1783rd to 1882nd positions are the second exon, the 2729th to 3059th positions are the third exon, the 3218th to 3634th positions are the fourth exon, the 3750th to 3800th positions are the fifth exon, the 4494th to 4560th positions are the sixth exon, and the 5574th to 5749th positions are the seventh exon.

[0078] The coding sequence of the OsC3HC4 gene in rice variety 93-11 is SEQ ID No: 2, and the encoded amino acid sequence is the OsC3HC4 protein of SEQ ID No: 1.

[0079] 2. Construction of recombinant plasmid SG2027-OsC3HC4 with knockout of OsC3HC4 gene

[0080] The nucleotide sequence of the recombinant plasmid SG2027-OsC3HC4 is SEQ ID No: 4 in the sequence table. SEQ ID No: 4 is a gene sequence obtained by Sanger sequencing, including sgRNA sequence, OsC3HC4 coding region sequence and SG2027 vector sequence on both sides of the insertion sequence. The map of the recombinant plasmid SG2027-OsC3HC4 is shown in Figure 1 .

[0081] SG2027-OsC3HC4 expresses sgRNA targeting the OsC3HC4 gene, the target sequence is: 5'-CCTCTCCCCATAGTAGAATA-3' (the nucleotide sequence is positions 5404-5423 of SEQ ID No: 3), and the target site of the sgRNA is located in the 6th intron of the OsC3HC4 gene.

[0082] 3. Obtaining and identifying OsC3HC4 gene knockout rice

[0083] The recombinant plasmid SG2027-OsC3HC4 obtained in step 2 was introduced into Agrobacterium tumefaciens EHA105 (Shanghai Weidi Company) to obtain recombinant Agrobacterium. The recombinant Agrobacterium was used to genetically transform the embryonic callus of rice 93-11 by the Agrobacterium infection method, and then the resistant callus was screened (100 mg / L hygromycin was used for resistance screening), and then differentiation regeneration culture was carried out, and then rooting culture was carried out to obtain regenerated plants.

[0084] The specific steps are as follows:

[0085] (1) Take out the mature seeds of rice 93-11, remove the shells, and select the plump, smooth and sterile seeds for disinfection.

[0086] (2) The sterilized rice 93-11 seeds were inoculated onto the induction medium and cultured at 28°C in the dark for about 14 days, and callus tissues with good appearance and good growth were selected.

[0087] (3) The recombinant vector SG2027-OsC3HC4 constructed in step 2 above was introduced into Agrobacterium tumefaciens EHA105 to obtain the recombinant bacterium EHA105 / SG2027-OsC3HC4.

[0088] (4) Take the recombinant bacteria EHA105 / SG2027-OsC3HC4 obtained in step (3), resuspend the bacteria in infection medium (MS liquid medium + 50 g / L sucrose + 50 μL / L Silwet L-77) to obtain EHA105 / SG2027-OsC3HC4 bacterial suspension.

[0089] (5) Soak the 93-11 callus tissue from step (2) in the EHA105 / SG2027-OsC3HC4 bacterial suspension prepared in step (4) for infection for 20 minutes. After infection, pour out the bacterial suspension, take the callus tissue, dry it with sterile filter paper, and then place it on a co-culture medium (MS basic medium) with acetosyringone and glucose, and culture it in the dark at 28° C. for 50-55 hours.

[0090] (6) After completing step (5), callus tissues without obvious Agrobacterium on the surface were selected and transferred to an antibacterial medium (MS basic medium) with cephalosporin added, and cultured in the dark at 28° C. for 3-4 days.

[0091] (7) The callus tissue after the above culture was transferred to a screening medium (MS basic medium) supplemented with hygromycin and cephalosporin and cultured in the dark at 28°C for 30 days, with subculturing every 10 days.

[0092] (8) After completing step (7), fresh hygromycin-resistant callus tissue was taken and inoculated into a pre-regeneration medium (MS basic medium), cultured in the dark at 28° C. for 7 days, and then placed in a light culture room (12 h light / 12 h dark) for another 7 days, and then transferred to a regeneration medium and continued to be cultured in the light until regenerated plants grew out, thereby obtaining candidate OsC3HC4 gene knockout rice plants.

[0093] The transgenic plants obtained using the recombinant vector SG2027-OsC3HC4 were recorded as OsC3HC4 transgenic plants.

[0094] The formulas of induction medium and differentiation medium are both MS medium (Solabo, M8521).

[0095] 4. Identification of OsC3HC4 gene knockout rice

[0096] Plants to be tested: 93-11 (control group) and candidate OsC3HC4 gene knockout plants obtained in step 3.

[0097] The genomic DNA of the leaves of the OsC3HC4 gene knockout rice plants to be tested was extracted, and PCR amplification was performed using the genomic DNA as a template and a primer pair consisting of primer OsC3HC4-F1 and primer OsC3HC4-R1.

[0098] OsC3HC4-F1: 5'-ACCTGTAAATCCAGACAAGTCG-3';

[0099] OsC3HC4-R1:5'-CTTGAGAACACTTCCGGCCT-3'.

[0100] The SG2027-OsC3HC4 plasmid was used as a positive control (V), and the acceptor variety 93-11 was used as a negative control (CK), and the resulting products were sequenced.

[0101] Identified by sequencing ( Figure 2 ), compared with the genomic DNA of 93-11, the genes encoding the OsC3HC4 protein in the two homologous chromosomes of the mutant type osc3hc4-1 underwent the following mutation: "5'-CCTCTCCCCATAGTAGAATA-3' (corresponding to positions 5404 to 5423 of SEQ ID No: 3)" mutated to "5'-CCTCTCCATAGTAGAAT-3', i.e., the deletion of two bases "CC", causing a frameshift mutation in OsC3HC4, resulting in loss of its function, thereby knocking out the gene encoding the OsC3HC4 protein. The sequencing results of the mutation site and its surrounding nucleotides are shown in Figure 2 .

[0102] Compared with the genomic DNA of 93-11, the genes encoding the OsC3HC4 protein in the two homologous chromosomes of the mutant type osc3hc4-2 underwent the following mutation: "5'-CCTCTCCCCATAGTAGAATA-3' (corresponding to positions 5404 to 5423 of SEQ ID No: 3)" mutated to "5'-CCTCTCCCCCATAGTAGAATA-3'", that is, one base "C" was inserted, causing a frameshift mutation in OsC3HC4, resulting in loss of its function, thereby knocking out the gene encoding the OsC3HC4 protein. The sequencing results of the mutation site and its surrounding nucleotides are shown in Figure 2 .

[0103] Through the above identification, two homozygous edited plants (i.e., the mutations in the two homologous chromosomes were consistent) were obtained and named OsC3HC4-1 and OsC3HC4-2, respectively.

[0104] The T1 generation rice mutant plants of the above-mentioned OsC3HC4 gene homozygous mutation types osc3hc4-1 and osc3hc4-2 lines were further cultivated to screen out T2 generation Osc3hc4 plants without transgenic elements, and their phenotypic characteristics were identified.

[0105] The Osc3hc4-1 plant is self-pollinated and seeds are harvested, and the seeds are cultivated into plants, which are T1 generation plants. The T1 generation plants are self-pollinated and seeds are harvested, which are T2 generation seeds. The Osc3hc4-1 plant and its self-pollinated progeny are called Osc3hc4-1 strains.

[0106] The Osc3hc4-2 plant is self-pollinated and seeds are harvested, and the seeds are cultivated into plants, which are T1 generation plants. The T1 generation plants are self-pollinated and seeds are harvested, which are T2 generation seeds. The Osc3hc4-2 plant and its self-pollinated progeny are called Osc3hc4-2 strains.

[0107] Example 2: Comparison of rice production traits

[0108] The plants to be tested are: T3 generation homozygous strains of rice 93-11, mutant strain Osc3hc4-1, and Osc3hc4-2.

[0109] The seeds of each plant to be tested were germinated and raised in a greenhouse (starting from the time of white appearance, for a total of 3 weeks) to obtain 3-week seedlings. The 3-week seedlings were subjected to high temperature stress treatment (45°C for 48 h) and the survival rate was counted. At least 60 individual plant data were counted for each material. The survival rate was calculated as follows: Survival rate (%) = (total number of rice individual plants - number of dead rice individual plants) / total number of rice individual plants × 100%.

[0110] The growth of the plants to be tested is shown in Figure 3 Compared with 93-11, the high temperature stress phenotypes of Osc3hc4-1 and Osc3hc4-2 were not significantly changed in plant height and growth rate under normal conditions (CK) during the seedling stage. Figure 3 However, under high temperature stress (HS), the survival rate of 93-11 was 0%, while the survival rates of Oscam3 knockout mutant plants Oscam3-1 and Oscam3-2 were 35% and 38%, respectively. Compared with 93-11, Osc3hc4-1 and Osc3hc4-2 showed higher survival rates, with the survival rates of Osc3hc4-1 and Osc3hc4-2 increasing by 35% and 38%, respectively ( Figure 3 (middle B).

[0111] The present invention has been described in detail above. For those skilled in the art, without departing from the purpose and scope of the present invention, and without the need to carry out unnecessary experimental conditions, the present invention can be implemented in a wide range under equivalent parameters, concentrations and conditions. Although the present invention provides specific embodiments, it should be understood that the present invention can be further improved. In a word, according to the principles of the present invention, the application is intended to include any changes, uses or improvements to the present invention, including departure from the disclosed scope in the application, and changes made with conventional techniques known in the art.

Claims

1. Use of a protein or a substance that regulates the activity or content of the protein or regulates the expression of a gene encoding the protein in any of the following: 1) Application in regulating plant's ability to tolerate high temperatures; 2) Application in the preparation of products for regulating the high temperature tolerance of plants; 3) Application in breeding plants with altered high temperature tolerance; 4) Application in the preparation of products for cultivating plants with altered high temperature tolerance; 5) Application in plant breeding; The protein is any of the following: a1) a protein having an amino acid sequence of SEQ ID No: 1; a2) a protein having the same function as the amino acid sequence shown in SEQ ID No: 1 after one or more amino acid residues are substituted and / or deleted and / or added; a3) a protein having an amino acid sequence identity of more than 80% with that of a1) or a2) and having the same function; a4) A fusion protein obtained by connecting a tag to the end of the protein defined in any one of a1) to a3).

2. The use according to claim 1, characterized in that: The protein is derived from rice.

3. The use according to claim 1 or 2, characterized in that: The substance that regulates the activity or content of the protein or regulates the expression of the gene encoding the protein is a biological material related to the protein in the application of claim 1 or 2, and the biological material is any one of the following: c1) a 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) a recombinant microorganism containing the nucleic acid molecule described in c1), or a recombinant microorganism containing the expression cassette described in c2), or a recombinant microorganism 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 molecule 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) a nucleic acid molecule that inhibits, reduces or silences 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) a recombinant microorganism containing the nucleic acid molecule described in e1), or a recombinant microorganism containing the expression cassette described in e2), or a recombinant microorganism 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 molecule 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).

4. The use according to claim 3, characterized in that: c1) The nucleic acid molecule is a DNA molecule as shown in any of the following: d1) the nucleotide sequence is a DNA molecule shown in SEQ ID No: 3; d2) the coding region sequence is the DNA molecule shown in SEQ ID No: 2; d3) a DNA molecule having 90% or more identity with the nucleotide sequence defined in d1) or d2) and encoding the protein described in claim 1; d4) A DNA molecule which hybridizes with the nucleotide sequence defined in d1) or d2) under stringent conditions and encodes the protein described in claim 1.

5. A method for improving the high temperature resistance of plants, characterized in that: The method comprises step P, wherein step P is to inhibit, reduce or silence the activity and / or content of the protein described in claim 1 or 2 in the target plant, or / and, inhibit, reduce or silence the expression level of the gene encoding the protein described in claim 1 or 2, so as to improve the plant's ability to withstand high temperatures.

6. A method for reducing the high temperature tolerance of plants, characterized in that: The method comprises step M, wherein step M is to enhance, increase or up-regulate the activity and / or content of the protein described in claim 1 or 2 in the target plant, or / and enhance, increase or up-regulate the expression level of the gene encoding the protein described in claim 1 or 2 to reduce the plant's ability to withstand high temperatures.

7. A method for breeding plants with enhanced high temperature tolerance, characterized in that: The invention comprises inhibiting, reducing or silencing the expression level of the gene encoding the protein described in claim 1 or 2 in the receptor plant, and / or the activity and / or content of the protein in the plant having enhanced high temperature resistance, wherein the high temperature resistance of the plant with enhanced high temperature resistance is stronger than that of the receptor plant.

8. The method according to claim 7, characterized in that: The steps include: (1) constructing a recombinant expression vector for inhibiting, reducing or silencing the gene encoding the protein described in claim 1 or 2; (2) Transforming the recombinant expression vector constructed in step (1) into a recipient plant to obtain a plant having a higher heat resistance than the recipient plant.

9. The protein according to claim 1 or 2 and / or the biomaterial according to claim 3 or 4.

10. The use according to any one of claims 1 to 4, and / or the method according to any one of claims 5 to 8, characterized in that: The plant is any of the following: N1) monocots or dicots; N2) Gramineae; N3) Gramineae; N4) Oryza plants; N5) Rice.

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