CN-121991970-A - Cauliflower BoFBX gene, expression vector thereof and application of gene in regulating and controlling tightness degree of cauliflower bulbs

CN121991970ACN 121991970 ACN121991970 ACN 121991970ACN-121991970-A

Abstract

The invention discloses a broccoli BoFBX gene and an expression vector thereof and application thereof in regulating and controlling the tightness degree of broccoli balls. The invention discovers that BoFBX gene is obviously up-regulated in loose cauliflower bulbs through transcriptome difference genes and WGCNA analysis at different development stages of compact cauliflower and loose cauliflower, the nucleotide sequence of BoFBX gene is shown as SEQ ID No.1, an agrobacterium-mediated genetic transformation method is adopted to introduce an over-expression vector into a high-generation inbred line variety of compact cauliflower to obtain an over-expressed positive transgenic cauliflower plant, and the field observation of the cauliflower phenotype shows that the over-expressed positive transgenic cauliflower plant bulbs of BoFBX genes are changed into loose type from compact type. The invention has application value in creating cauliflower germplasm of a flower ball with ideal tightness degree or breeding loose type cauliflower varieties and the like.

Inventors

YANG YINGXIA
YAO XINGWEI
SUN DELING

Assignees

天津市农业科学院

Dates

Publication Date: 20260508
Application Date: 20260214

Claims (10)

1. A BoFBX gene isolated from broccoli, wherein the nucleotide sequence of the cDNA of BoFBX gene is selected from any one of the nucleotide sequences set forth in (a) - (e) below: (a) A polynucleotide sequence shown in SEQ ID No. 1; (b) A polynucleotide sequence encoding the amino acid sequence shown in SEQ ID No. 2; (c) A polynucleotide sequence capable of hybridizing to the polynucleotide sequence of (a) or (b) under stringent hybridization conditions, the polynucleotide sequence still having the function of controlling cauliflower ball tightness, (d) a polynucleotide sequence having at least 75% or more identity to any one of the polynucleotide sequences of (a) - (c), the polynucleotide sequence still having the function of controlling cauliflower ball tightness, preferably, a polynucleotide sequence having at least 85% or more identity to any one of the polynucleotide sequences of (a) - (c), the polynucleotide sequence still having the function of controlling cauliflower ball tightness, more preferably, a polynucleotide sequence having at least 90% or more identity to any one of the polynucleotide sequences of (a) - (c), the polynucleotide sequence still having the function of controlling cauliflower ball tightness, most preferably, the polynucleotide sequence having at least 95% or more identity to any one of the polynucleotide sequences of (a) - (c), the polynucleotide sequence still having the function of controlling cauliflower ball tightness; (e) A polynucleotide sequence complementary to the polynucleotide sequence of any one of (a) - (d), which polynucleotide sequence still has the function of regulating the degree of tightness of cauliflower bulbs.
2. The protein F-box encoded by BoFBX gene of claim 1, wherein the amino acid sequence of said protein F-box is selected from the amino acid sequences shown in any one of the following (a) to (d): (a) An amino acid sequence shown in SEQ ID No. 2; (b) A protein variant obtained by deleting or replacing one or more amino acid residues in the amino acid sequence shown in SEQ ID No.2, wherein the protein variant still has the function or activity of regulating the tightness degree of cauliflower bulbs; (c) A protein variant obtained by inserting one or more amino acid residues into the amino acid sequence shown in SEQ ID No.2, wherein the protein variant still has the function or activity of regulating the tightness degree of cauliflower bulbs; (d) A protein which has 85% or more identity with the amino acid sequence shown in SEQ ID No.2, and still has the function or activity of regulating the tightness degree of cauliflower bulbs.
3. An expression cassette comprising the BoFBX gene of claim 1.
4. An expression vector comprising the BoFBX gene of claim 1, preferably said expression vector is an over-expression plant vector.
5. A recombinant host cell comprising the recombinant expression vector of claim 4.
6. Use of BoFBX gene according to claim 1, protein F-box according to claim 2, expression cassette according to claim 3 or expression vector according to claim 4 for regulating the tightness of cauliflower bulbs.
7. The method of claim 6, wherein the method comprises overexpressing BoFBX gene in broccoli to increase the expression level of BoFBX gene in broccoli or to increase the function or activity of the protein encoded by F-box gene.
8. The use according to claim 6, wherein the adjusting of the tightness of the cauliflower ball is such that the ball branches grow, the ball branch pinch becomes larger or the ball becomes loose.
9. A method for cultivating a loose cauliflower variety is characterized in that BoFBX genes are overexpressed in the cauliflower, so that the expression level of BoFBX genes in the cauliflower is enhanced or the function or activity of the encoded protein of an F-box gene is enhanced, and the cauliflower variety with growing cauliflower branches, enlarged cauliflower branch clamp angles or loose cauliflower is obtained through screening.
10. A method for loosening cauliflower bulbs, which is characterized in that BoFBX genes are overexpressed in the cauliflower, so that the expression level of BoFBX genes in the cauliflower is enhanced or the function or activity of a coded protein of BoFBX genes is enhanced, and the cauliflower bulbs branches are increased, the pinch angles of the bulbs branches are enlarged or the bulbs are loosened.

Description

Cauliflower BoFBX gene, expression vector thereof and application of gene in regulating and controlling tightness degree of cauliflower bulbs Technical Field The invention relates to a gene separated from vegetables and application thereof, in particular to BoFBX gene separated from cauliflower and an expression vector thereof and application thereof in regulating and controlling the tightness degree of a flower ball, belonging to the field of cauliflower BoFBX gene and application thereof. Background Broccoli (Brassica oleracea var. Botrytis) is one of important vegetable crops, and is popular with consumers because of its high nutritive value, good taste and wide adaptability. The tightness of the cauliflower ball is one of key characters for determining the quality and market price of the commodity, and is closely related to the appearance, the taste, the storage and transportation resistance and the consistency of the commodity of the cauliflower ball. Therefore, how to accurately regulate the tightness of the cauliflower is a technical problem which needs to be overcome in the current breeding and production management of the cauliflower. The prior researches show that the flower ball tightness has typical quantitative character characteristics, is regulated by multiple genes, and is closely related to plant hormone, development regulation network and meristem structure development. However, the key regulatory genes, molecular mechanisms and applications thereof in variety improvement are still very limited, and the definite target genes are not used for molecular breeding screening and precise improvement. This bottleneck severely restricts the innovation speed of high-quality varieties of broccoli, and also results in a lack of effective genetic control means for the stability of the curd structure in the industrial production process. The F-box family of proteins is an important component of the widely distributed ubiquitin-proteasome pathway in plants, originally found in Cyclin F, and is the core component of the SCF (SKP 1-Cullin-F-box) ubiquitin E3 ligase complex (Glickman m.h. et al, 2002; jain m., 2007). The F-box protein is named because the N end of the F-box protein contains about 40-50 amino acids in length and has an F-box motif with a combination of conserved Leu-Pro dipeptide and hydrophobic amino acids (Val, ile and the like), can be combined with SKP1 to form an SCF complex, and can participate in various important biological processes such as plant growth and development, hormone signal transduction, photomorphogenesis, stress resistance regulation and the like by recognizing and degrading specific substrate proteins. It has been shown that F-box protein plays a key role in plant development regulation, but its function in cauliflower ball structure development, especially in the formation of tightness, is not clear. Disclosure of Invention It is an object of the present invention to provide BoFBX gene isolated from broccoli and its encoded protein. It is a further object of the present invention to provide an expression vector containing the BoFBX gene isolated from broccoli and a recombinant host cell containing the expression vector. The invention also aims to apply the BoFBX gene separated from the cauliflower and the expression vector thereof to the regulation of the tightness degree of the cauliflower ball. In order to achieve the above object, the present invention adopts the technical scheme that: an aspect of the present invention provides BoFBX genes isolated from broccoli, the nucleotide sequence of the cDNA of the genes being selected from any one of the nucleotide sequences set forth in (a) - (e) below: (a) A polynucleotide sequence shown in SEQ ID No. 1; (b) A polynucleotide sequence encoding the amino acid sequence shown in SEQ ID No. 2; (c) A polynucleotide sequence capable of hybridizing to the polynucleotide sequence of (a) or (b) under stringent hybridization conditions, the polynucleotide sequence still having the function of controlling cauliflower ball tightness, (d) a polynucleotide sequence having at least 75% or more identity to any one of the polynucleotide sequences of (a) - (c), the polynucleotide sequence still having the function of controlling cauliflower ball tightness, preferably, a polynucleotide sequence having at least 85% or more identity to any one of the polynucleotide sequences of (a) - (c), the polynucleotide sequence still having the function of controlling cauliflower ball tightness, more preferably, a polynucleotide sequence having at least 90% or more identity to any one of the polynucleotide sequences of (a) - (c), the polynucleotide sequence still having the function of controlling cauliflower ball tightness, most preferably, the polynucleotide sequence having at least 95% or more identity to any one of the polynucleotide sequences of (a) - (c), the polynucleotide sequence still having the function of controlling cauliflower ball tightne