层出镰孢锌金属蛋白酶FpMep的功能研究  

Functional analysis of the zinc metalloprotease FpMep in Fusariumproliferatum

作　　者：高贻宙 李海博 王艺潼 何四明 吴志宏[1] GAO Yizhou;LI Haibo;WANG Yitong;HE Siming;WU Zhihong(School of Biological and Chemical Engineering,Zhejiang University of Science and Technology,Hangzhou 310023,Zhejiang,China)

机构地区：[1]浙江科技学院生物与化学工程学院,浙江杭州310023

出　　处：《菌物学报》2024年第5期60-79,共20页Mycosystema

基　　金：浙江科技学院人才引进启动经费(F701103M09)。

摘　　要：植物病原真菌层出镰孢Fusariumproliferatum可引起苜蓿根腐病,影响作物产量,危害人畜健康及食品安全,而目前关于层出镰孢关键致病基因及其作用机制的研究报道较少。胞外锌金属蛋白酶是一类在植物病原真菌侵染寄主过程中发挥重要作用的分泌蛋白。本研究对植物病原真菌中一个显著受寄主诱导表达且具有信号肽分泌活性的锌金属蛋白酶FpMep的功能进行研究。该蛋白在植物病原真菌中高度保守,具有典型的锌离子蛋白酶功能基序(HEXXH)。通过构建FpMep基因敲除突变体并对其进行表型观察,发现FpMep基因可正调控营养生长及产孢,且在层出镰孢响应各种环境胁迫中起着不同的作用。FpMep基因的敲除导致层出镰孢对苜蓿的致病力显著下降。本研究进一步通过转录组测序技术,分析了FpMep对基因群组网络的调控,发现在ΔFpMep突变体中,编码转运蛋白、翻译后修饰酶类、代谢酶类、转录因子等多种类型的致病相关基因表达显著改变,为进一步揭示FpMep调控致病性的作用机制提供了思路。Fusarium proliferatum is a plant pathogen that causes root rot disease,posing a substantial threat to agricultural productivity,human and animal health,and food safety.However,comprehensive studies about the virulence-related genes and their underlying mechanisms of F.proliferatum are relatively scarce.Extracellular zinc metalloproteinases are a class of secreted proteins that play important roles during infection by fungal pathogens.The function of one zinc metalloproteinase FpMep in F.proliferatum,which is up-regulated by host induction and shows secretory activity,was studied.FpMep contains the typical conserved feature motif(HEXXH)of the zinc-dependent proteinase family.Through the construction of the FpMep gene knockout mutant,coupled with phenotypic observations,it was found that FpMep could positively regulate mycelial growth and conidial production of F.proliferatum,and played an important role in response to diverse environmental stresses.FpMep displayed the reduction of virulence to alfalfa.RNA sequencing and comparative transcriptome analysis revealed that the expression levels of several types of virulence-related genes,such as ggenes encoding transporters,post-translational modification enzymes,metabolic enzymes and transcription factors were differentially expressed in FpMep,and these findings provide new insights for the analysis of the pathogenic mechanism of F.proliferatum.

关 键 词：层出镰孢 苜蓿根腐病 锌金属蛋白酶 致病力 分泌蛋白 

分 类 号：S432.44[农业科学—植物病理学]