玉米大斑病菌转录因子StMSN4基因的克隆及表达模式分析

Cloning and expression pattern analysis of transcription factor gene StMSN4 in Setosphaeria turcica

为明确玉米大斑病菌转录因子StMSN4基因的结构特征及其在病菌重要生长发育时期的表达模式,本试验以酿酒酵母ScMSN4氨基酸序列为探针,在玉米大斑病菌基因组数据库中搜索并克隆其同源基因,并对该基因的结构及其编码蛋白的理化性质、空间结构等进行预测;通过分析病菌关键生长发育阶段的RNA-Seq数据,明确该基因的表达模式。结果发现,在玉米大斑病菌基因组中搜索并克隆得到了ScMSN4的同源基因,将其命名为StMSN4;该基因DNA全长为1357 bp,cDNA全长为1296 bp,包含2个外显子,1个内含子;其编码蛋白包含431个氨基酸,含有2个典型ZnF-C2H2保守结构域。通过对病菌的菌丝、分生孢子、芽管、附着胞和侵入钉时等5个典型发育时期的RNA-Seq数据分析表明,StMSN4基因在5个发育时期均有表达,且表达水平较高,表明该基因在病菌的生长发育阶段发挥着重要的作用。本研究不仅明确了StMSN4基因的结构特性及其表达模式,也为深入研究该基因的功能及HOG-MAPK信号转导途径的作用机制奠定了基础。

In order to determine the structural characteristics of the transcription factor StMSN4 gene and its expression pattern at different growth and development stages in Setosphaeria turcica, the amino acid sequence of ScMSN4 from Saccharomyces cerevisiae was used as a probe to search the homologous gene in the genome database of S. turcica. The physicochemical properties and spatial structures were further analyzed and predicted. The RNASeq data obtained in our previous research was employed to clarify the expression pattern of the gene at different stages of growth and development of the pathogen. The results found that the homologous gene of ScMSN4 was obtained in the genome of S. turcica, and it was cloned and designed as StMSN4. The full length DNA of the gene was 1 357 bp and the full-length cDNA was 1 296 bp. The gene had two exons and one intron, encoded 431 amino acids, and contained 2 typical ZnF-C2H2 conserved domains. The RNA-Seq data based on five typical developmental stages including hypha, conidium, germ tube, appressorium and penetration peg showed that StMSN4 was expressed at the 5 developmental stages, and the expression level was high, which indicated that StMSN4 gene played an important role in the growth and development stages of pathogens. This study not only confirms the structural characteristics of StMSN4 and its expression pattern, but also lays the foundation for further elucidating the functions of this gene and the mechanism of HOG-MAPK signal transduction pathway.