蓖麻WRKY转录因子的全基因组鉴定及其进化分析

Genome-wide identification and phylogenetic analysis of WRKY transcription factor family in castor bean

为探讨WRKY转录因子在蓖麻耐胁迫中可能的生物学功能,研究基于已公布的基因组和EST数据对蓖麻WRKY转录因子家族进行全面鉴定和系统命名,并在此基础上分析了其基因结构和进化特征。结果显示,蓖麻基因组中至少存在56个WRKY基因,它们散布于39条scaffolds上,所含内含子数目在1～5个;RcWRKYs包含1～2个WRKY结构域,根据WRKY结构域的数量及其锌指结构的特征,这些蛋白可分为I、IIa、IIb、IIc、IId、IIe和III类/亚类。与拟南芥相比,蓖麻的WRKY基因在物种分化后并未明显进化,它们中的大部分在拟南芥中都有同源基因;相对而言,在不同类基因中,I类的WRKY基因得到了较快的进化。

With the published genome and EST sequences, a genome-wide search was carried out for genes encoding RcWRKYs, a type of plant-specific transcription factor which was shown to be one of the most important transcription factor families involved in biotic and abiotic stress response of plants. As a result, a total of 56 RcWRKYs were identified and then nominated as RcWRKY1 to RcWRKY56 based on their gene structure and phylogenesis. The RcWRKYs containing one to five introns each were distributed across 39 of the 25 800 scaffolds. According to the number of WRKY domain and the type of zine finger, the identified RcWRKYs were grouped intoⅠ, Ⅱa, Ⅱb, Ⅱc, Ⅱd, lie or Ⅲ class or subclass. Comparative genome analysis suggests that the Ricinus WRKY family didn＇ t expand ferent class or significantly in the history for most of them have ortholog genes in Arabidopsis thaliana. Among difsubclass of RcWRKYs, this class may have evolved in a faster pace