二穗短柄草GRFs基因家族的鉴定及表达模式分析

Whole Genome Identification and Analysis of GRFs Gene Family in Brachypodium distachyon

GRFs基因家族在植物生长发育及逆境响应中起着重要的调控作用。为了探明二穗短柄草GRFs基因家族的基本特征及其进化关系,本研究利用生物信息学方法在全基因组水平上对二穗短柄草GRFs基因家族成员进行鉴定与分析。结果表明,二穗短柄草GRFs基因家族包括12个家族成员,蛋白质序列长度在238~577个氨基酸之间;序列比对发现二穗短柄草GRFs家族基因包括2个保守的QLQ和WRC结构域及广泛的保守基序;染色体定位发现,12个家族成员在二穗短柄草的5条染色体上呈不均匀分布,bd03号染色体分布最多;系统发育关系比较分析表明,这些GRFs基因家族成员存在4对直系同源基因。RT-qPCR分析表明,全部GRFs基因家族成员在二穗短柄草幼嫩组织中表达量较高,而在根系和衰老组织中表达量较低,外源激素特别是GA3诱导了二穗短柄草大部分GRFs基因家族成员的上调表达,表明GRFs基因家族广泛地参与了二穗短柄草分生组织功能和器官形成的生命进程。本研究结果为二穗短柄草GRFs家族蛋白功能的研究奠定了理论基础。

Growth-regulating factors play important roles in plant growth and development as well as plant tolerance to abiotic stress. To investigate the characteristics of GRFs gene family and their evolutionary relationship, GRFs gene family in Brachypodium distachyon were identified and analyzed using bioinformatics method. The results showed that Brachypodium distachyon contained 12 GRF genes. The length of protein sequence ranged letween 238 and 577 aa. The sequence alignment analysis showed that GRF genes have two conserved domains: QLQ and WRC, and a wide range of conservative motif. All the GRF genes were found to be distributed unevenly in the five chromosomes with the maximum in bd03. Based on phylogenetic relationship in Brachypodium distachyon, four pairs of orthologous genes were revealed. RT-qPCR analysis found that expression level of all the GRF genes were higher in actively growing tissues than in senescent tissue and root, and most GRF genes were induced by exogenous hormones, especially GA3, suggesting that most of GRF genes were involed in the meristem function and organ formation. The results of this study could provide a theoretical foundation for the protein function analysis of the GRFs family in Brachypodium distachyon.