Tomato chlorosis virus CPm protein is a pathogenicity determinant and suppresses host local RNA silencing induced by single-stranded RNA

Frontiers in Microbiology

Microbiology

Fan Li¹  Xian OuYang²  Yu Zhang²  Xiao Yang³  Yong Liu⁴  Zhanhong Zhang⁴  Deyong Zhang⁴  Xiangwen Luo⁴  Xiaobin Shi⁴  Songbai Zhang⁴  Xiaoyuan Lv⁵ 

[1] College of Plant Protection, Yunnan Agricultural University, Kunming, China;Key Laboratory of Pest Management of Horticultural Crop of Hunan Province, Hunan Plant Protection Institute, Hunan Academy of Agricultural Science, Changsha, Hunan, China;Longping Branch, College of Biology, Hunan University, Changsha, Hunan, China;Longping Branch, College of Biology, Hunan University, Changsha, Hunan, China;Key Laboratory of Pest Management of Horticultural Crop of Hunan Province, Hunan Plant Protection Institute, Hunan Academy of Agricultural Science, Changsha, Hunan, China;Technical Center of Changsha Customs, Changsha, Hunan, China;

关键词: Tomato chlorosis virus;    CPm protein;    pathogenicity determinant;    RNA silencing suppressor;    posttranscriptional gene silencing;   

DOI  :  10.3389/fmicb.2023.1151747

 received in 2023-01-26, accepted in 2023-03-10,  发布年份 2023

来源: Frontiers

【 摘 要 】

IntroductionTomato chlorosis virus (ToCV) is a typical member of the genus Crinivirus, which severely threatens Solanaceae crops worldwide. The CPm protein encoded by ToCV has been reported to be associated with virus transmission by vectors and is involved in RNA silencing suppression, while the mechanisms remain ambiguous.MethodsHere, ToCV CPm was ectopically expressed by a Potato virus X (PVX) vector and infiltrated into Nicotiana benthamiana wild-type and GFP-transgenic16c plants.ResultsThe phylogenetic analysis showed that the CPm proteins encoded by criniviruses were distinctly divergent in amino acid sequences and predicted conserved domains, and the ToCV CPm protein possesses a conserved domain homologous to the TIGR02569 family protein, which does not occur in other criniviruses. Ectopic expression of ToCV CPm using a PVX vector resulted in severe mosaic symptoms followed by a hypersensitive-like response in N. benthamiana. Furthermore, agroinfiltration assays in N. benthamiana wilt type or GFP-transgenic 16c indicated that ToCV CPm protein effectively suppressed local RNA silencing induced by single-stranded but not double-stranded RNA, which probably resulted from the activity of binding double-stranded but not single-stranded RNA by ToCV CPm protein.ConclusionTaken together, the results of this study suggest that the ToCV CPm protein possesses the dual activities of pathogenicity and RNA silencing, which might inhibit host post-transcriptional gene silencing (PTGS)-mediated resistance and is pivotal in the primary process of ToCV infecting hosts.

【 授权许可】

Unknown   
Copyright © 2023 Yang, Luo, Zhang, Zhang, OuYang, Shi, Lv, Li, Zhang, Liu and Zhang.