The Structure Analysis Of Transcription Factor StSte12and Screening Of Downstream Target Genes Of StSte12in Setosphaeria Turcica

A transcription factor gene StSTE12of Setosphaeria turcica, which was a possibledownstream gene in Fus3/Kss1-homolog MAPK cascade pathway, was cloned. ThreeRNAi transformants with different gene silencing efficiency were also obtained in theprevious study. The location of StSTE12in S. turcica genome as well as the structurecharacteristics of the transcription factor protein were confirmed using bioinformaticstechnology in this research. The possible downstream regulatary genes were searched fromS.turcica genome datebase. The expression patterns of these genes were detected in term ofreverse transcription PCR and Real-time PCR technonlogy by analyzing StSTE12RNAisilencing transformants and the downstream regulatary genes of StSte12was determined inthe study. The main results were as follows:1. StSTE12was in the sites from1061747to1064127in positive-strand ofscaffold₁3and its identity was105656using bioinformatics methods. StSte12containedconserved domains and space structure of Ste12-like proteins, such as STE homeodomainand ZnF_C2H2domain.2. The expression level of transcription factor StSte12in different development stages,including mycelium development, conidium and appressorium formation was detected byWestern blotting techniques, showing that Stste12appeared the highest expression level inthe stage of appressorium formation.3. The downstream target genes of transcription factor ScSte12were obtained bysearching S. cerevisiae genome database and their homologous genes were acquired byscanning S.turcica genome database. All downstream target genes of S.turcica sharedconserved domains （T\C GAAAC A\G）, and the sequence GAAAC was highly conservedin the domain.4. StSte12downstream regulatary genes, such as StBEM2, StBUD8,StCHS7, StPCK1, StKAR5, StRAX2, StBEM1and StSHO1, was identified by analyzing StSTE12RNAitransformants using RT-PCR as well as Real-time PCR technonlogy.