Geminiviral C2 proteins inhibit active autophagy to facilitate virus infection by impairing the interaction of ATG7 and ATG8  

作　　者：Buwei Cao Linhao Ge Mingzhen Zhang Fangfang Li Xueping Zhou 

机构地区：[1]State Key Laboratory for Biology of Plant Diseases and Insect Pests,Institute of Plant Protection,Chinese Academy of Agricultural Sciences,Beijing 100193,China [2]State Key Laboratory of Rice Biology,Institute of Biotechnology,Zhejiang University,Hangzhou 310058,China

出　　处：《Journal of Integrative Plant Biology》2023年第5期1328-1343,共16页植物学报（英文版）

基　　金：support from the National Natural Science Foundation of China(31930089)to X.Z.;the National Key Research and Development Program of China(2021YFD1400400)to F.L.

摘　　要：Autophagy is a conserved intracellular degradation process that plays an active role in plant response to virus infections.Here we report that geminiviruses counteract activated autophagymediated antiviral defense in plant cells through the C2 proteins they encode.We found that,in Nicotiana benthamiana plants,tomato leaf curl Yunnan virus(TLCYnV)infection upregulated the transcription levels of autophagy-related genes(ATGs).Overexpression of NbATG5,NbATG7,or NbATG8a in N.benthamiana plants decreased TLCYnV accumulation and attenuated viral symptoms.Interestingly,transgenic overexpression of NbATG7 promoted the growth of N.benthamiana plants and enhanced plant resistance to TLCYnV.We further revealed that the C2 protein encoded by TLCYnV directly interacted with the ubiquitinactivating domain of ATG7.This interaction competitively disrupted the ATG7–ATG8 binding in N.benthamiana and Solanum lycopersicum plants,thereby inhibiting autophagy activity.Furthermore,we uncovered that the C2-mediated autophagy inhibition mechanism was conserved in three other geminiviruses.In summary,we discovered a novel counter-defensive strategy employed by geminiviruses that enlists their C2 proteins as disrupters of ATG7–ATG8 interactions to defeat antiviral autophagy.

关 键 词：AUTOPHAGY C2 counterdefense GEMINIVIRUS plant defense the ATG7–ATG8 interaction 

分 类 号：S432.41[农业科学—植物病理学]