玉米大斑病菌GPCRs超家族的基因鉴定及其在孢子发育过程中的转录模式  

Gene Identification of GPCRs Superfamily and Its Transcriptional Profile During Conidial Development of Setosphaeria turcica

作　　者：于波[1] 张玉妹[1] 李志勇[2] 吴迪[1] 巩校东[1] 申珅[1] 曹志艳[1] 郝志敏[1] 董金皋[1] 

机构地区：[1]河北农业大学生命科学学院/河北省植物生理与分子病理学重点实验室,保定071001 [2]河北省农林科学院谷子研究所,石家庄050031

出　　处：《农业生物技术学报》2016年第9期1302-1311,共10页Journal of Agricultural Biotechnology

基　　金：国家自然科学基金项目(No.31301616);河北省高等学校青年拔尖人才计划项目(No.BJ2014349Y);河北省自然科学基金项目(No.C2014204111;No.C2016204160)

摘　　要：G蛋白偶联受体（G protein-coupled receptors,GPCRs）广泛存在于动物、植物以及微生物中,是最大的涉及信号转导的膜受体家族。本研究通过基于隐马尔科夫模型的HMMER 3.0软件搜索玉米大斑病菌（Setosphaeria turcica）基因组数据库,鉴定并获得GPCRs超家族基因及其基因组定位;采用MEGA 6.0软件进行系统进化分析;通过通用样品数据系统（generalized sample data system,GSDS）工具进行基因结构分析;利用Inter Pro和SMART工具分析GPCRs的保守结构域。进一步利用q RT-PCR技术,对所确定的GPCR基因在分生孢子发育形成侵染结构的过程中不同阶段的相对表达量进行分析。结果表明,在玉米大斑病菌基因组中至少有9个典型的GPCR,其中3个属氮源感应因子类,信息素受体和碳源感应因子类各2个,类环磷酸腺苷受体和真菌视蛋白类各1个。这些基因散布在玉米大斑病菌基因组中,且结构复杂多样,但所有成员编码产物均由N端、7个跨膜结构域、3个胞内环、3个胞外环及C端组成。每个跨膜结构域包含20~25个氨基酸。以分生孢子为对照,所有基因在附着胞成熟时期接种后12 h（12 hours post inoculation,12 hpi）均显著下调（P〈0.05）;除基因St Rtc1和Stfdd123以外,全部基因整体变化趋势均呈现上调/持平（3 hpi）-上调（6 hpi）-下调（12 hpi）-上调（24 hpi）的规律,尤其在侵入丝形成时期（24 hpi）显著上调（P〈0.05）。在附着胞形成时期（6 hpi）,仅St Ste2p和St Rtc2表达显著上调。St Rtc1和Stfdd123在各阶段中的表达量与对照差异不显著或显著降低。本研究为深入解析植物病原真菌GPCR超家族的功能提供了理论依据。G protein coupled receptors （GPCRs） constitute the biggest transmembrane receptor superfamily which mediates the signal transduction and generally exists in animals, plants and microbes. The genes encoding GPCRs and their genomic locations were obtained and identified by searching the genome database of Setosphaeria turcica with the HMMER 3.0 software based on hidden markov model. The MEGA 5.0 software was employed to analyze the systemic evolution. Genetic structure conservative sites of GPCRs were analyzed online through generalized sample data system （GSDS）, InterPro and SMART. It was finally confirmed that there were 9 GPCR genes in the genome of S. turcica. Three of them belonged to putative nitrogen sensors, while there were 2 pheromone receptors and 2 carbon sensors respectively. And the remaining 2 were classified as cyclic adenosine monophosphate （cAMP） receptor-like protein and Fungal opsin. GPCR superfamily genes distributed in the genome randomly, and its structure was complicated. All members consisted of N-terminal, seven transmembrane domains, three intracellular loops, three extracellular loops and C-terminal. Each transmembrane domain comprised 20 to 25 amino acids. Finally, relative expression quantities of GPCR genes in the invasive structure formation process were detected by using the qRT-PCR technology. Transcriptional pattern analysis showed that in appressorium mature period 12 hours post inoculation （hpi）, all genes were significantly downregulated （P〈0.05）. Except StRtcl and Stfdd123, trends of other genes all showed a downregulated/fiat （3 hpi）-upregulated （6 hpi）- downregulated （12 hpi）- upregulated （24 hpi）. Especially, they were significantly upregulated （/9〈0.05） during the invasive mycelium formation （24 hpi）. In appressorial formation period （6 hpi）, only StSte2p and StRtc2 significantly upregulated. The expression levels of StRtcl and Stfdd123 in each stage were not significant or significantly downregulated. This study provides

关 键 词：玉米大斑病菌 G蛋白偶联受体 侵染 转录模式 

分 类 号：S435.131[农业科学—农业昆虫与害虫防治]