DNA Geminivirus Infection Induces an Imprinted E3 Ligase Gene to Epigenetically Activate Viral Gene Transcription. Issue 10 (7th August 2020)

• Record Type: Journal Article
• Authors: Chen, Zhong-Qi; Zhao, Jian-Hua; Chen, Qian; Zhang, Zhong-Hui; Li, Jie; Guo, Zhong-Xin; Xie, Qi; Ding, Shou-Wei; Guo, Hui-Shan
• Is Part Of: The Plant Cell. Volume 32:Issue 10(2020)
• Page Start: 3256
• Page End: 3272
• Publication Date: 2020-08-07
• DOI: 10.1105/tpc.20.00249
• Languages: English
• ISSNs: 1040-4651

Abstract

Abstract : Geminivirus infection induces the expression of a plant imprinted E3 ligase gene, leading to the proteosomal degradation of DNA methyltransferases and epigenetic activation of viral gene transcription. Abstract: Flowering plants and mammals contain imprinted genes that are primarily expressed in the endosperm and placenta in a parent-of-origin manner. In this study, we show that early activation of the geminivirus genes C2 and C3 in Arabidopsis ( Arabidopsis thaliana ) plants, encoding a viral suppressor of RNA interference and a replication enhancer protein, respectively, is correlated with the transient vegetative expression of VARIANT IN METHYLATION5 ( VIM5 ), an endosperm imprinted gene that is conserved in diverse plant species. VIM5 is a ubiquitin E3 ligase that directly targets the DNA methyltransferases MET1 and CMT3 for degradation by the ubiquitin-26S proteasome proteolytic pathway. Infection with Beet severe curly top virus induced VIM5 expression in rosette leaf tissues, possibly via the expression of the viral replication initiator protein, leading to the early activation of C2 and C3 coupled with reduced symmetric methylation in the C2-3 promoter and the onset of disease symptoms. These findings demonstrate how this small DNA virus recruits a host imprinted gene for the epigenetic activation of viral gene transcription. Our findings reveal a distinct strategy used by plant pathogens to exploit the host machinery in order to inhibit methylation-mediated defense responses when establishing infection.