陆地棉油菜素内酯信号基因GhBES1家族的鉴定及表达分析

Identification and Expression Analysis of the Brassinosteroid Signal Gene GhBES1 Family in Upland Cotton

BES1基因是植物激素油菜素内酯信号转导过程中的重要转录因子,为了解陆地棉油菜素内酯信号基因Gh BESI家族,通过对陆地棉异源四倍体标准系TM-1基因组数据库的全面分析和鉴定,获得21个GhBES1基因,这些基因分布在不同的亚基因组,有9对基因在A亚组和D亚组上存在对应关系,AD亚组对应基因序列一致性高于95%。根据进化分析,21个GhBES1基因分为4个亚家族,除了亚家族Ⅲ,其他3个亚家族在拟南芥中均有对应基因;除了亚家族Ⅳ基因和亚家族Ⅱ中GhBES1-1基因外,其他GhBES1基因均有2个外显子。亚细胞定位结果表明,21个GhBES1蛋白主要定位到细胞核、细胞质等部位,其中7对基因的蛋白亚细胞定位完全一致。GhBES1基因在根、茎、叶、顶端分生组织中均有表达,但不同亚家族基因在不同组织中的表达水平存在差异。研究结果为棉花GhBES1基因家族功能的深入研究奠定了基础。

BES1 gene is a major transcription factor responsible for brassinosteroid-regulated gene expression and plant growth. In order to know the family of GhBES1 gene in upland cotton,21 GhBES1 genes were identified from the genome sequence database of upland cotton（ Gossypium hirsutum L. acc. TM-1）. These GhBES1 genes were found to be distributed on different subgenomes. There were 9 pairs of GhBES1 genes in the A and D subgenomes with one-to-one correspondence relationship,and the gene sequence identity of the correspondence genes were higher than 95%. Based on the results of phylogenetic tree,the 21 GhBES1 genes could be divided into four subfamilies,and there were homologous genes of Arabidopsis thaliana L. in each subfamily,except for subfamily Ⅲ;GhBES1 genes had two exons,except for genes in subfamily Ⅳ and GhBES1-1 in subfamily Ⅱ. The result of subcellular localization indicated that 21 GhBES1 proteins were primarily located in nuclear and cytoplasmic,and 7pairs of GhBES1 genes had the same location. The tissue expression analysis showed that GhBES1 genes were expressed in the leaf,root,stem and shoot apical meristem,but the expression level of GhBES1 genes in different subfamily were different. These results provide a theoretical basis on cloning and functional research of GhBES1 genes.