棉花WRKY转录因子家族成员的鉴定和生物信息学分析

Genome-wide Identification and Analysis of WRKY Transcription Factors in G.arboretum

WRKY转录因子家族在植物抵御各种生物、非生物胁迫反应和生长发育调控中扮演着重要角色。利用生物信息学方法鉴定和分析棉花A基因组WRKY转录因子,共鉴定得到109个候选WRKY基因,编码区全长474~3 528 bp,基因分布在棉花13条染色体上。依据WRKY家族基因的保守结构域和系统进化关系,将其划分为3个大组:G1组、G2组和G3组。G1组WRKY基因包括21个成员,其中18个含有两个WRKY域;G2组有73个成员,可进一步分为G2-a、G2-b、G2-c、G2-d和G2-e五个亚类;G3组WRKY基因包括15个成员。同组的WRKY成员保守域的氨基酸构成大体相似,但也存在WRKYGQK多肽和锌指结构的变异,不同组成员的氨基酸保守域组成特异。拟南芥和棉花WRKY基因的系统进化树表明,功能相似的基因聚在一起,暗示和拟南芥抗逆功能基因聚类在一起Ga WRKY可能参与棉花抵御逆境胁迫反应,为进一步发现和挖掘棉花WRKY基因的功能奠定理论基础。

The WRKY transcription factor family is widely involved in regulating plant development and defense response against various biotic and abiotic stresses. In this study,the gene number,classification,conserved motif of the WRKY transcriptional factors in G. arboretum were analyzed. A total of 109 Ga WRKYs were identified in G. arboretum. The coding sequences were 474 ~ 3 528 bp in length,and the genes were distributed in 13 different chromosomes. According to the structural feature of WRKY domain and evolution of the protein family,the 109 Ga WRKYs were classified into 3 groups（ G1,G2 and G3）. G1 included 21 WRKY members,among which 18 members had 2 WRKY domains; G2 included 73 WRKY members,and they were divided into 5 subgroups（ G2-a,G2-b,G2-c,G2-d and G2-e）; G3 had 15 WRKY members. The WRKY transcription factors showed similar motif compositions within each group,but there were variants of WRKYGQK peptide and zinc finger motif. However,the amino acid conserved domains of WRKY members were different among different groups. Phylogenetic trees of the WRKY gene of Arabidopsis thaliana and cotton showed that functional similar genes got together. It indicated that those Ga WRKYs together with Arabidopsis thaliana anti reverse function gene were likely involved in plant responses to various stresses. The present results provided theoretical basis for further discovery and mining functional WRKY gene in cotton.