Unveiling a novel entry gate:Insect foregut as an alternative infection route for fungal entomopathogens  

作　　者：Yiling Lai Weilu Zheng Yitong Zheng Haiquan Lu Shuang Qu Lili Wang Muwang Li Sibao Wang 

机构地区：[1]New Cornerstone Science Laboratory,CAS Key Laboratory of Insect Developmental and Evolutionary Biology,CAS Center for Excellence in Molecular Plant Sciences,Chinese Academy of Sciences(CAS),Shanghai 200032,China [2]CAS Center for Excellence in Biotic Interactions,University of Chinese Academy of Sciences,Beijing 100049,China [3]Sericultural Research Institute,Jiangsu University of Science and Technology,Zhenjiang 212000,China

出　　处：《The Innovation》2024年第4期42-53,41,共13页创新（英文）

基　　金：funded by the National Natural Science Foundation of China(grant nos.32021001,32230015,and 32272622);the National Key R&D Program of China(grant no.2023YFA1801000);the New Cornerstone Science Foundation,Chinese Academy of Sciences(317GJHZ2022028GC);Youth Innovation Promotion Association CAS(grant no.2021272).

摘　　要：Insects and their natural microbial pathogens are intertwined in constant arms races,with pathogens continually seeking entry into susceptible hosts through distinct routes.Entomopathogenic fungi are primarily believed to infect host insects through external cuticle penetration.Here,we report a new variety,Beauveria bassiana var.majus(Bbm),that can infect insects through the previously unrecognized foregut.Dual routes of infection significantly accelerate insect mortality.The pH-responsive transcription factor PacC in Bbm exhibits rapid upregulation and efficient proteolytic processing via PalC for alkaline adaptation in the foregut.Expression of PalC is regulated by the adjacent downstream gene Aia.Compared to non-enteropathogenic strains such as ARSEF252,Aia in Bbm lacks a 249-bp fragment,resulting in its enhanced alkaline-induced expression.This induction promotes PalC upregulation and facilitates PacC activation.Expressing the active form of BbmPacC in ARSEF252 enables intestinal infection.This study uncovers the pH-responsive Aia-PalC-PacC cascade enhancing fungal alkaline tolerance for intestinal infection,laying the foundation for developing a new generation of fungal insecticides to control destructive insect pests.

关 键 词：alkaline SEEKING enable 

分 类 号：Q96[生物学—昆虫学]