芜菁花叶病毒P3蛋白的C末端区域通过将P3靶向病毒复制复合体对病毒感染至关重要。

The C-terminal region of the Turnip mosaic virus P3 protein is essential for viral infection via targeting P3 to the viral replication complex.

作者信息

Cui Xiaoyan, Yaghmaiean Hoda, Wu Guanwei, Wu Xiaoyun, Chen Xin, Thorn Greg, Wang Aiming

机构信息

Institute of Vegetable Crops, Jiangsu Academy of Agricultural Sciences, Nanjing, Jiangsu 210014, China; London Research and Development Centre, Agriculture and Agri-Food Canada, London, Ontario N5V 4T3, Canada; Department of Biology, Western University, London, Ontario N6A 5B7, Canada.

London Research and Development Centre, Agriculture and Agri-Food Canada, London, Ontario N5V 4T3, Canada; Department of Biology, Western University, London, Ontario N6A 5B7, Canada.

出版信息

Virology. 2017 Oct;510:147-155. doi: 10.1016/j.virol.2017.07.016. Epub 2017 Jul 20.

DOI:10.1016/j.virol.2017.07.016

PMID:28735115

Abstract

Like other positive-strand RNA viruses, plant potyviruses assemble viral replication complexes (VRCs) on modified cellular membranes. Potyviruses encode two membrane proteins, 6K2 and P3. The former is known to play pivotal roles in the formation of membrane-associated VRCs. However, P3 remains to be one of the least characterized potyviral proteins. The P3 cistron codes for P3 as well as P3N-PIPO which results from RNA polymerase slippage. In this study, we show that the P3N-PIPO of Turnip mosaic virus (TuMV) is required for viral cell-to-cell movement but not for viral replication. We demonstrate that the C-terminal region of P3 (P3C) is indispensable for P3 to form cytoplasmic punctate inclusions and target VRCs. We reveal that TuMV mutants that lack P3C are replication-defective. Taken together, these data suggest that the P3 cistron has two distinct functions: P3N-PIPO as a dedicated movement protein and P3 as an essential component of the VRC.

摘要

与其他正链RNA病毒一样，植物马铃薯Y病毒在修饰的细胞膜上组装病毒复制复合体（VRCs）。马铃薯Y病毒编码两种膜蛋白，6K2和P3。已知前者在与膜相关的VRCs形成中起关键作用。然而，P3仍是特征最少的马铃薯Y病毒蛋白之一。P3顺反子编码P3以及由RNA聚合酶滑动产生的P3N-PIPO。在本研究中，我们表明芜菁花叶病毒（TuMV）的P3N-PIPO是病毒细胞间运动所必需的，但不是病毒复制所必需的。我们证明P3的C末端区域（P3C）对于P3形成细胞质点状内含物和靶向VRCs是不可或缺的。我们发现缺乏P3C的TuMV突变体复制有缺陷。综上所述，这些数据表明P3顺反子有两个不同的功能：P3N-PIPO作为一种专门的运动蛋白，P3作为VRC的一个重要组成部分。