Journal of Plant Pathology

, Volume 101, Issue 1, pp 135–140 | Cite as

Identification of an RNA silencing suppressor encoded by citrus vein enation virus

  • Zhen SongEmail author
  • Yanjiao Wang
  • Tiantian Cui
  • Yu Bin
  • Janhong Yan
  • Changyong ZhouEmail author
Original Article


In order to know if any protein encoded by citrus vein enation virus (CVEV) might act as an RNA silencing suppressor (RSS), five open reading frames (ORF) of CVEV, including the coat protein (CP) gene, were individually cloned into the binary expression vector pBI121. The silencing suppression ability of the five ORFs was tested by ‘viral minireplicon infectivity assays’ based on a beet yellows virus (BYV) minireplicon carrying a reporter gene (BYVminiR-GFP). GFP imaging and microscopic analyses were used to observe whether RNA silencing suppression occurred or not. In addition, real-time quantitative RT-PCR was used to quantify the mRNA expression of GFP in the injected region. The fluorescence intensity of leaves with CP expression was stronger than that of the empty vector negative control, but it was weaker than that of the positive control HC-Pro of tobacco etch virus (TEV), indicating that the CP of CVEV partly inhibited the GFP gene silencing. Co-expression of each of the other four ORFs with BYVminiR-GFP showed an almost complete quenching of GFP fluorescence in infiltrated areas, similar to that of the negative control. The amount of GFP mRNA in the leaves co-expressed with CP was nearly twice as much as that of either the negative control or other ORFs. These results suggest that CP of CVEV is a weak gene silencing suppressor.


CVEV CP RSS Viral minireplicon infectivity assays 



We are grateful to Prof. Valerian V. Dolja (Department of Botany and Plant Pathology, Oregon State University, USA) for providing us with BYVminiR-GFP. This work was supported by the National Key Research and Development Program of China (Grant Nos. 2017YFD0202002 and 2017YFE0110900), and the Fundamental Research Funds for the Central Universities of China (Grant Nos. XDJK2017B024 and XDJK2018AA002).


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Copyright information

© Società Italiana di Patologia Vegetale (S.I.Pa.V.) 2018

Authors and Affiliations

  1. 1.Citrus Research Institute of Southwest UniversityChongqingChina

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