Identification of a movement protein of the tenuivirus rice stripe virus.
Rice stripe virus (RSV) is the type member of the genus Tenuivirus. RSV has four single-stranded RNAs and causes severe disease in rice fields in different parts of China. To date, no reports have described how RSV spreads within host plants or the viral and/or host factor(s) required for tenuivirus movement. We investigated functions of six RSV-encoded proteins using trans-complementation experiments and biolistic bombardment. We demonstrate that NSvc4, encoded by RSV RNA4, supports the intercellular trafficking of a movement-deficient Potato virus X in Nicotiana benthamiana leaves. We also determined that upon biolistic bombardment or agroinfiltration, NSvc4:enhanced green fluorescent protein (eGFP) fusion proteins localize predominantly near or within the walls of onion and tobacco epidermal cells. In addition, the NSvc4:eGFP fusion protein can move from initially bombarded cells to neighboring cells in Nicotiana benthamiana leaves. Immunocytochemistry using tissue sections from RSV-infected rice leaves and an RSV NSvc4-specific antibody showed that the NSvc4 protein accumulated in walls of RSV-infected leaf cells. Gel retardation assays revealed that the NSvc4 protein interacts with single-stranded RNA in vitro, a common feature of many reported plant viral movement proteins (MPs). RSV NSvc4 failed to interact with the RSV nucleocapsid protein using yeast two-hybrid assays. Taken together, our data indicate that RSV NSvc4 is likely an MP of the virus. This is the first report describing a tenuivirus MP.
Xiong
Ruyi
R
State Key Laboratory of Rice Biology, Institute of Biotechnology, Zhejiang University, Hangzhou 310029, People's Republic of China.
Wu
Jianxiang
J
Zhou
Yijun
Y
Zhou
Xueping
X
D016679:Genome, Viral / Q000235:genetics; D016253:Microscopy, Immunoelectron; D019590:Nucleocapsid Proteins / Q000235:genetics / Q000378:metabolism; D019697:Onions / Q000235:genetics / Q000378:metabolism / Q000821:virology; D018515:Plant Leaves / Q000235:genetics / Q000378:metabolism / Q000821:virology; D053830:Plant Viral Movement Proteins / Q000235:genetics / Q000378:metabolism*; D017863:Potexvirus / Q000235:genetics / Q000378:metabolism; D011485:Protein Binding; D012313:RNA / Q000378:metabolism; D029364:Tenuivirus / Q000235:genetics / Q000378:metabolism*
D019590:Nucleocapsid Proteins; D053830:Plant Viral Movement Proteins; D012313:RNA