3H-31, A Non-structural Protein of Heliothis virescens ascovirus 3h,Inhibits the Host Larval Cathepsin and Chitinase Activities

作     者：Huan Yu Yi-Yi Ou-Yang Chang-Jin Yang Ni Li Madoka Nakai Guo-Hua Huang Huan Yu;Yi-Yi Ou-Yang;Chang-Jin Yang;Ni Li;Madoka Nakai;Guo-Hua Huang

作者机构：Hunan Provincial Key Laboratory for Biology and Control of Plant Diseases and Insect PestsHunan Agricultural UniversityChangsha 410128China College of Plant ProtectionHunan Agricultural UniversityChangsha 410128China Tokyo University of Agriculture and TechnologySaiwaiFuchuTokyo 183-8509Japan 

出 版 物：《Virologica Sinica》 (中国病毒学（英文版）)

年 卷 期：2021年第36卷第5期

页      面：1036-1051页

核心收录：

学科分类：0710[理学-生物学] 1007[医学-药学(可授医学、理学学位)] 1002[医学-临床医学] 1001[医学-基础医学(可授医学、理学学位)] 09[农学] 0904[农学-植物保护] 

基　　金：supported by the National Natural Science Foundation of China(32070168,31700141,31872027) Provincial Natural Science Foundation of Hunan(2019JJ50234) Changsha Science and Technology Project(kq1901033) Double first-class construction project of Hunan Agricultural University Sakura Science Plan of Japan Science Technology Agency(JST)。 

主　　题：Cathepsin Chitinase Heliothis virescens ascovirus 3h(HvAV-3h) Recombinant virus 3h-31 

摘      要：3h-31 of Heliothis virescens ascovirus 3h(Hv AV-3h)is a highly conserved gene of ascoviruses.As an early gene of Hv AV-3h,3h-31 codes for a non-structural protein(3H-31)of Hv AV-3h.In the study,3h-31 was initially transcribed and expressed at 3 h post-infection(hpi)in the infected Spodoptera exigua fat body cells(Se FB).3h-31 was further inserted into the bacmid of Autographa californica nucleopolyhedrovirus(Ac MNPV)to generate an infectious baculovirus(Ac MNPV-31).In vivo experiments showed that budded virus production and viral DNA replication decreased with the expression of 3H-31,and lucent tubular structures were found around the virogenic stroma in the Ac MNPV-31-infected Se FB cells.In vivo,both LD50and LD90values of Ac MNPV-31 were significantly higher than those of the wild-type Ac MNPV(Ac MNPV-wt)in third instar S.exigua larvae.An interesting finding was that the liquefaction of the larvae killed by the infection of Ac MNPV-31 was delayed.Chitinase and cathepsin activities of Ac MNPV-31-infected larvae were significantly lower than those of Ac MNPV-wt-infected larvae.The possible regulatory function of the chitinase and cathepsin for 3H-31 was further confirmed by RNAi,which showed that larval cathepsin activity was significantly upregulated,but chitinase activity was not significantly changed due to the RNAi of 3h-31.Based on the obtained results,we assumed that the function of 3H-31 was associated with the inhibition of host larval chitinase and cathepsin activities,so as to restrain the hosts in their larval stages.