HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via CrossRef Citing Articles via Google Scholar Google Scholar Articles by Zhang, C. Articles by Qiu, B. Search for Related Content PubMed PubMed Citation Articles by Zhang, C. Articles by Qiu, B. Agricola Articles by Zhang, C. Articles by Qiu, B.

Rice black streaked dwarf virus P9-1, an -helical protein, self-interacts and forms viroplasms in vivo

Chaozheng Zhang^1,

Yueyong Liu^2,

Liyue Liu^3,

¹ Center for Agricultural Biotechnology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, PR China
² California Pacific Medical Center Research Institute, San Francisco, CA 94107, USA
³ Bureau of Animal Husbandry and Fishery of Xiangxiang, Xiangxiang 411400, PR China
⁴ Laboratory of Structural Biology, School of Life Sciences and Bio-Engineering, Tsinghua University, Beijing 100084, PR China
⁵ Hebei Academy of Agricultural Sciences, Baoding 071000, PR China

Correspondence
Bingsheng Qiu
qiubs{at}sun.im.ac.cn

Replication and assembly of viruses from the family Reoviridae are thought to take place in discrete cytoplasmic inclusion bodies, commonly called viral factories or viroplasms. Rice black streaked dwarf virus (RBSDV) P9-1, a non-structural protein, has been confirmed to accumulate in these intracellular viroplasms in infected plants and insects. However, little is known about its exact function. In this study, P9-1 of RBSDV-Baoding was expressed in Escherichia coli as a His-tagged fusion protein and analysed using biochemical and biophysical techniques. Mass spectrometry and circular dichroism spectroscopy studies showed that P9-1 was a thermostable, -helical protein with a molecular mass of 41.804 kDa. A combination of gel-filtration chromatography, chemical cross-linking and a yeast two-hybrid assay was used to demonstrate that P9-1 had the intrinsic ability to self-interact and form homodimers in vitro and in vivo. Furthermore, when transiently expressed in Arabidopsis protoplasts, P9-1 formed large, discrete viroplasm-like structures in the absence of infection or other RBSDV proteins. Taken together, these results suggest that P9-1 is the minimal viral component required for viroplasm formation and that it plays an important role in the early stages of the virus life cycle by forming intracellular viroplasms that serve as the sites of virus replication and assembly.

These authors contributed equally to this work.

The GenBank/EMBL/DDBJ accession number for the sequence reported in this study is DQ407917.