Deletion of all three MAP kinase genes results in severe defects in stress responses and pathogenesis in Fusarium graminearum  

作　　者：Jingyi Ren Yuhan Zhang Yuhua Wang Chengliang Li Zhuyun Bian Xue Zhang Huiquan Liu Jin-Rong Xu Cong Jiang 

机构地区：[1]State Key Laboratory of Crop Stress Biology for Arid Areas and NWAFU-Purdue Joint Research Center,College of Plant Protection,Northwest A&F University,Yangling 712100,Shaanxi,China [2]Department of Botany and Plant Pathology,Purdue University,West Lafayette,IN 47907,USA

出　　处：《Stress Biology》2022年第1期621-633,共13页逆境生物学（英文）

基　　金：supported by grants from the National Youth Talent Support Program and National Natural Science Foundation of China(no.31772114)to JC and grants from NSWBSI to JRX。

摘　　要：Mitogen-activated protein kinase(MAPK)cascades are activated by external stimuli and convert signals to cellular changes.Individual MAPKs have been characterized in a number of plant pathogenic fungi for their roles in pathogenesis and responses to biotic or abiotic stresses.However,mutants deleted of all the MAPK genes have not been reported in filamentous fungi.To determine the MAPK-less effects in a fungal pathogen,in this study we generated and characterized mutants deleted of all three MAPK genes in the wheat scab fungus Fusarium graminearum.The Gpmk1 mgv1 Fghog1 triple mutants had severe growth defects and was non-pathogenic.It was defective in infection cushion formation and DON production.Conidiation was reduced in the triple mutant,which often produced elongated conidia with more septa than the wild-type conidia.The triple mutant was blocked in sexual reproduction due to the loss of female fertility.Lack of any MAPKs resulted in an increased sensitivity to various abiotic stress including cell wall,osmotic,oxidative stresses,and phytoalexins,which are likely related to the defects of the triple mutant in environmental adaptation and plant infection.The triple mutant also had increased sensitivity to the biocontrol bacterium Bacillus velezensis and fungus Clonostachys rosea.In co-incubation assays with B.velezensis,the Gpmk1 mgv1 Fghog1 mutant had more severe growth limitation than the wild type and was defective in conidium germination and germ tube growth.In confrontation assays,the triple mutant was defective in defending against mycoparasitic activities of C.rosea and the latter could grow over the mutant but not wild-type F.graminearum.RNA-seq and metabolomics analyses showed that the MAPK triple mutant was altered in the expression of many ATP-binding cassette(ABC)and major facilitator superfamily(MFS)transporter genes and the accumulation of metabolites related to arachidonic acid,linoleic acid,and alpha-linolenic acid metabolisms.Overall,as the first study on mutants deleted of all three MAPKs in

关 键 词：Abiotic stresses Fungal-bacterial interaction Gibberella zeae MYCOPARASITISM Signal transduction 

分 类 号：Q94[生物学—植物学]