摘要
大豆[Glycine max(L.)Merr.]能与根瘤菌形成共生关系,实现生物固氮。油菜素类固醇(BR,brassinosteroid)是调控植物生长发育的重要激素,对大豆结瘤具有负调控作用,但油菜素甾醇受体BRI1在大豆共生固氮方面的功能尚不明确。因此,鉴定与解析GmBRI1基因家族成员的特征与功能对于揭示GmBRI1在大豆生长发育中的作用至关重要。本研究利用生物信息学方法在大豆基因组中共鉴定出6个GmBRI1基因,非均匀地分布在4条染色体上,氨基酸数量在1136~1211 aa之间,亮氨酸占比最高,均为酸性稳定蛋白。系统发育分析显示,GmBRI1基因家族可分为3个亚家族,同一亚家族的基因结构和保守基序分布高度相似。共线性分析表明片段复制是GmBRI1基因家族扩张的主要原因。GmBRI1基因家族的启动子上含有丰富的调控大豆光响应、激素响应、逆境响应和生长发育过程的顺式作用元件。GmBRI1的潜在磷酸化位点数量在111~132个之间。同时预测了与GmBRI1互作的蛋白有19个,直接结合的有9个,通过与多种蛋白互作参与到BR信号转导途径中调控多种生物学过程。GmBRI1家族基因在根和根瘤中均表达,而且GmBRI1a、GmBRI1b、GmBRL1a和GmBRL1b在受到根瘤菌侵染后下调表达。本研究为大豆GmBRI1基因的功能研究提供了新的理论依据,并证明了它们在根瘤菌侵染早期发生响应,这为深入了解GmBRI1基因家族在大豆共生结瘤中的功能与分子机制提供了基础信息。
Soybean[Glycine max(L.)Merr.]can form a symbiotic relationship with rhizobia for biological nitrogen fixation.Brassinosteroid(BR)as an important hormone regulates plant growth and development and negatively affects soybean nodulation.The function of brassinosteroid receptor BRI1 in symbiotic nitrogen fixation remains unclear.Therefore,analysis of the characteristics and functions of GmBRI1 gene family members is crucial for revealing their roles in soybean growth and development.In this study,six GmBRI1 genes were identified in the soybean genome by bioinformatics methods.They were unevenly distributed on four chromosomes,encoding proteins with 1136 to 1211 amino acids,of which leucine was the most abundant.These proteins were acidic and stable proteins.Phylogenetic analysis divided the GmBRI1 gene family members into three subfamilies,with highly similar gene structures and conserved motifs within each subfamily.Synteny analysis indicated that the family expansion resulted from fragment duplication events.Promoter analysis revealed multiple cis-elements related to light,hormone,stress response and growth and development.The number of potential phosphorylation sites in GmBRI1 proteins ranged from 111 to 132.Protein interaction network prediction identified 19 interacting proteins and 9 directly binding proteins involved in BR signal transduction.The GmBRI1 family genes expressed in both roots and nodules,and four genes GmBRI1a,GmBRI1b,GmBRL1a and GmBRL1b were down-regulated after rhizobia infection.This study provided a new theoretical basis for the functional research of soybean GmBRI1 family genes,highlighting their response during the early stages of rhizobium infection,and advances our understanding of their functions and mechanisms in soybean symbiotic nodulation.
作者
杨家慧
黄乐香
刘郅贤
苏伯鸿
赵苗羽
邢程顺
刘宝辉
赵晓晖
YANG Jiahui;HUANG Lexiang;LIU Zhixian;SU Bohong;ZHAO Miaoyu;XING Chengshun;LIU Baohui;ZHAO Xiaohui(School of Life Sciences,Guangzhou University/Guangdong Provincial Key Laboratory of Plant Adaptation and Molecular Design,Guangzhou 510006)
出处
《植物遗传资源学报》
北大核心
2025年第5期989-1004,共16页
Journal of Plant Genetic Resources
基金
国家自然科学基金(32272135,32072013)。
