小麦BES1转录因子基因TaBEH3的克隆及表达分析

Cloning and Expression Analysis of BES1 Transcription Factor TaBEH3 Genes in Wheat

BES1(油菜素内酯不敏感1-甲磺酸乙酯-抑制剂1)是一类植物特有的转录因子家族, TaBEH3基因是小麦 BES1基因家族成员之一,为进一步了解该基因的功能,以中国春为材料,克隆了 TaBEH3基因,将其3个同源基因分别命名为 TaBEH3-A、 TaBEH3-B和 TaBEH3-D。序列分析显示,3个同源基因均包含2个外显子,分别编码356、354和358个氨基酸,启动子区含有大量与植物生长发育、激素响应相关的顺式作用元件,其中,分生组织表达元件(CAT-box)和脱落酸响应元件(ABRE)在3个基因中普遍存在。系统进化树分析显示, TaBEH3基因在麦类作物中具有更近的亲缘关系。基于qRT-PCR进行的时空表达分析显示, TaBEH3基因在不同组织和不同器官间均有组成性表达,表明 TaBEH3基因在植物生长发育(特别是花器官的发育和形成)过程中具有重要的作用。 TaBEH3-A、 TaBEH3-B和 TaBEH3-D基因响应ABA激素胁迫处理,且3个基因的表达量变化趋势一致。

BES1(brassinosteroid insensitive 1-EMS-suppressor 1) is a kind of plant-specific transcription factor family. TaBEH3 gene is one of the members of wheat BES1 gene family. In order to further study the function of TaBEH3, TaBEH3 genes were cloned from Chinese Spring in this study, and its three homologous genes were designated as TaBEH3-A, TaBEH3-B and TaBEH3-D, respectively. Sequence analysis showed that the three homologous genes all contain two exons, encoding 356, 354 and 358 amino acids, respectively. The promoter region contains a large number of cis-acting elements related to plant normal growth and development and plant hormones response, and the meristem expression element(CAT-box) and the abscisic acid response element(ABRE) are existed commonly in the three genes. Phylogenetic tree analysis showed that TaBEH3 genes have closer relationship among Triticeae crops.The spatiotemporal expression analysis by qRT-PCR showed that the TaBEH3 genes were constitutively expressed in different tissues and organs, indicating that TaBEH3 might play an important role in the normal growth and development of plant, especially in the development and formation of floral organs. TaBEH3-A, TaBEH3-B and TaBEH3-D genes responded to ABA hormone stress, and the expression levels of the three genes were consistent.