Abstract: 【Objective】 The objective of this study is to locate StSte12 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 StSte12 and its protein structures were analyzed using bioinformatics method. Its expression characteristics were detected by Western blot. The regulatory genes of StSte12 were screened according to ScSte12 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. StSte12 contained conserved domains (STE homeodomain and ZnF_C2H2 domain) and spatial structure of Ste12-like. In S. turcica appressorium period, the expression amount of StSTE12 was the largest. Some regulatory genes of StSte12 were screened, in which the binding motif combined with StSte12 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】 StSte12 has DNA binding domain and spatial structure belongs to Ste12-like Transcription factors. And it plays an important role in appressorium development of S. turcica. Some regulatory genes of StSte12 were screened, in which the binding motif was T\C GAAAC A\G, and which was regulated by StSte12.

Key words: Setosphaeria turcica , transcription factor , StSte12 , regulatory gene