G蛋白偶联受体(GPCR)腺苷酸环化酶(AcyA)途径介导赭曲霉群体感应现象的机制  

Mechanism of G protein coupled receptor(GPCR)-adenylyl cyclase(AcyA)pathway mediating quorum sensing in Aspergillus ochraceus

作　　者：许积康 贾继尧 梁志宏[1] XU Jikang;JIA Jiyao;LIANG Zhihong(College of Food Science and Nutritional Engineering,Beijing Advanced Innovation Center for Food Nutrition and Human Health,China Agricultural University,Beijing 100083,China)

机构地区：[1]中国农业大学北京食品营养与人类健康高精尖创新中心食品科学与营养工程学院,北京100083

出　　处：《生物加工过程》2024年第5期569-581,共13页Chinese Journal of Bioprocess Engineering

基　　金：国家自然科学基金面上项目(31671947)。

摘　　要：赭曲霉(Aspergillus ochraceus)是一种代表性的产毒模式真菌,存在密度依赖性转化的高、低群体密度阈值和携带这种密度信息的群体感应(QS)信号分子--氧脂素。本研究首先基于代表高、低群体密度条件的野生型赭曲霉转录组差异,分析群体密度这一环境条件对赭曲霉行为的影响,结果发现,除了氧脂素代表的细胞通信外,还具有种内对资源的竞争现象,体现在碳代谢。进一步,基于前期实验筛选到负责响应密度信息的膜受体GprC和主要的胞内效应器腺苷酸环化酶(AcyA),构建了基因缺陷型赭曲霉(ΔgprC和ΔacyA)。对比野生型与缺陷型赭曲霉的基因表达及行为差异后发现,GprC-AcyA途径缺陷后不仅中断了密度信息的传递,还直接影响赭曲霉的生命周期。本文研究结果表明,GprC和AcyA作为G蛋白网络的重要枢纽,具有广泛的调控作用,涉及生物过程、细胞组分、分子功能中大部分行为。本研究结果对利用生物手段进行真菌毒素污染的高效、绿色防治具有指导意义。Aspergillus ochraceus is a representative toxin-producing mode fungus.Both high and low population density thresholds have been identified for density-dependent transitions,and oxylipids have been discovered as quorum-sensing signaling molecules to carry this density information.Herein,we studied the influence of environmental conditions such as population density on the behavior of A.ochraceus based on the transcriptome differences between the high and low population density conditions of wild-type A.ochraceus.In addition to the cellular communication represented by oxylipids,the involvement of intraspecific competition for resources was also found,which was reflected in carbon metabolism.After the construction of genetically defective A.ochraceus(ΔgprC andΔacyA)based on the membrane receptor GprC and the main intracellular effector adenylyl cyclase(AcyA),we evaluated the differences between wild-type and defective A.ochraceus with regards to their gene expression and behavior.As a result,the defect of GprC-AcyA pathway could not only interrupt the transmission of density information,but also directly affect the life cycle of A.ochraceus,indicating that GprC and AcyA,as important hubs of the G-protein network,played a wide range of regulatory roles,involving most of the behaviors in biological processes,cellular components,and molecular functions.Our research will provide scientific guidance for the efficient and green prevention and control of mycotoxin pollution by biological means.

关 键 词：群体感应信号 G蛋白偶联受体 第二信使 赭曲霉毒素 赭曲霉 细胞通信 

分 类 号：Q939.9[生物学—微生物学]