[目的]确定玉米大斑病菌转录因子stStel2在基因组中的位置,分析目的蛋白质StStel2的结构特征;明确StSTEl2在病菌不同发育时期的表达情况;筛选可能受StStel2转录因子调控的基因,分析其匹配序列的结构特征,并比较它们在病菌的中表达情况。[方法]利用生物信息学方法,确定StStel2在玉米大斑病菌基因组中的位置并解析目的蛋白质stStel2的结构特征;利用Westernblot技术分析StSTEl2在病菌不同发育时期的表达规律;根据酿酒酵母Stel2转录因子的下游调控基因,筛选病菌中可能受StStel2调控的功能基因;并利用生物信息学方法得出下游调控基因的结合位点;利用RT—PCR技术,分析这些基因在StSTEl2RNAi转化子与野生型菌株中的表达情况。[结果]StSTEl2的ID为105656,该基因位于scaffold-13正链的1061747—1064127位置;该蛋白具有stel2-1ike蛋白特有的保守结构域(STEhomeodomain和ZnF—C2H2锌指结构)及空间结构;StSTE12在附着胞时期表达量最大;筛选了部分stStel2调控基因,与stStel2的匹配序列为T\CGAAACAkG,中间部分GAAAC非常保守;Stl(AR5在野生型中表达量小于StSTEl2RNAi转化子,StBEM2、StBED8、StCHS7相反;StRAX2的表达量在野生型和转化子中一致。[结论]StStel2具有stel2-like所特有的DNA结合结构域和空间结构;该蛋白在附着胞发育中发挥重要功能;筛选了部分stStel2的调控基因,其匹配序列可概括为T\CGAAACA\C,且证实了这些基因受StStel2调控。
[Objective] The objective of this study is to locate StStel2 in genome, analyze its protein structure, confirmate its expression at different developmental stages, screen its regulatory genes which expressions were compared in Setosphaeria turcica. [Method] The location of StStel2 and its protein structures were analyzed using bioinformatics method. Its expression characteristics were detected by Western blot. The regulatory genes of StStel2 were screened according to ScStel2 of Saccharomyces cerevisiae. The binding motif of these genes was analyzed by bioinformatics. The expression level of these genes was compared between wild type strain and StSTE12 RNAi transformants using RT-PCR. [Result] The identity of StSTE12 was 105656, locating 1061747 to 1064127 of positive-strand of scaffold_13. StStel2 contained conserved domains (STE homeodomain and ZnF C2H2 domain) and spatial structure of Stel2-1ike. In S. turcica appressorium period, the expression amount of StSTE12 was the largest.Some regulatory genes of StStel2 were screened, in which the binding motif combined with StStel2 was T/C GAAAC A/G. The expression level of StKAR5 in wild type strains was lager than that in StSTE12 RNAi transformants, the level of StBEM2, StBUD8, and StCHS7 were opposite to StKAR5, whereas that of StRAX2 had no obvious difference. [Conclusion] StStel2 has DNA binding domain and spatial structure belongs to Ste 12-like Transcription factors. And it plays an important role in appressorium development of S. turcica. Some regulatory genes of StStel2 were screened, in which the binding motif was T/C GAAAC A/C2 and which was regulated by StSte 12.