Pns4 of rice dwarf virus is a phosphoprotein, is localized around the viroplasm matrix, and forms minitubules Authors
First Online: 13 April 2006 Received: 06 January 2006 Accepted: 01 March 2006 DOI:
Cite this article as: Wei, T., Kikuchi, A., Suzuki, N. et al. Arch Virol (2006) 151: 1701. doi:10.1007/s00705-006-0757-4 Summary.
Rice dwarf virus (RDV), a member of the family
Reoviridae, has a 12-segmented dsRNA genome. Seven segments, designated S1, S2, S3, S5, S7, S8, and S9, encode structural proteins, while the remainder encode nonstructural proteins. One of the nonstructural proteins, Pns4, which is encoded by S4, was characterized. Pns4 was a phosphorylatable substrate in a phosphorylation assay in vivo; it associated with large cytoplasmic fibrils and formed novel minitubules in infected cultured cells of its leafhopper insect vector, as revealed by immunofluorescence and immunoelectron microscopy. Early in infection, Pns4 was detected at the periphery of the viroplasm, and it was then observed on amorphous or fibrillar inclusions, which were identified as bundles of minitubules, at later stages of infection. Since viroplasms are believed to be the site of RDV replication, the intracellular location of Pns4 suggests that this protein might be involved in the process of assembly of the RDV virion. References
Boccardo G, Milne RG (1984) Plant reovirus group. In: Murant AF, Harrison BD (eds), CM/AAB descriptions of plant viruses. Commonwealth Mycological Institute and Association of Applied Biologists, Unwin Brothers Ltd, The Gresham Press, Old Woking, England, pp 294
Cao, X, Zhou, P, Zhang, X, Zhu, S, Zhong, X, Xiao, Q, Ding, B, Li, Y 2005 Identification of an RNA silencing suppressor from a plant double-stranded RNA virus J Virol 79 13018 13027 PubMed CrossRef Das, SC, Pattnaik, AK 2004 Phosphorylation of vesicular stomatitis virus phosphoprotein P is indispensable for virus growth J Virol 78 6420 6430 PubMed CrossRef Eaton, BT, Hyatt, AD, Brookes, SM 1990 The replication of bluetongue virus Curr Top Microbiol Immunol 162 89 118 PubMed Eaton, BT, Hyatt, AD, White, JR 1987 Association of bluetongue virus with the cytoskeleton Virology 157 107 116 PubMed CrossRef Eaton, BT, Hyatt, AD, White, JR 1988 Localization of the nonstructural protein NS1 in bluetongue virus-infected cells and its presence in virus particles Virology 163 527 537 PubMed CrossRef Hemonnot, B, Cartier, C, Gay, B, Rebuffat, S, Bardy, M, Devaux, C, Boyer, V, Briant, L 2004 The host cell MAP kinase ERK-2 regulates viral assembly and release by phosphorylating the p6gag protein of HIV-1 J Biol Chem 279 32426 32434 PubMed CrossRef Kimura, I 1986 A study of rice dwarf virus in vector cell monolayers by fluorescent antibody focus counting J Gen Virol 67 2119 2124 Kimura, I, Omura, T 1988 Leafhopper cell cultures as a means for phytoreovirus research Adv Dis Vector Res 5 111 135 Kimura, T 1981 Immuno-electron microscopic study on the antigenicity of tubular structures associated with human rotavirus Infect Immunol 33 611 615 Kimura, T, Hase, A 1987 Three different forms of tubular structures associated with the replication of bovine rotavirus in a tissue culture system Arch Virol 92 165 174 PubMed CrossRef Law, LM, Everitt, JC, Beatch, MD, Holmes, CF, Hobman, TC 2003 Phosphorylation of rubella virus capsid regulates its RNA binding activity and virus replication J Virol 77 1764 1771 PubMed CrossRef Lepault, J, Petitpas, I, Erk, I, Navaza, J, Bigot, D, Dona, M, Vachette, P, Cohen, J, Rey, FA 2001 Structural polymorphism of the major capsid protein of rotavirus EMBO J 20 1498 1507 PubMed CrossRef Li, Y, Bao, YM, Wei, CH, Kang, ZS, Zhong, YW, Mao, P, Wu, G, Chen, ZL, Schiemann, J, Nelson, RS 2004 Rice dwarf phytoreovirus segment S6-encoded nonstructural protein has a cell-to-cell movement function J Virol 78 5382 5389 PubMed CrossRef Lin, NS 1984 Gold–IgG complexes improve the detection and identification of viruses in leaf dip preparation J Virol Methods 8 81 190 CrossRef Miyazaki, N, Hagiwara, K, Naitow, H, Higashi, T, Cheng, RH, Tsukihara, T, Nakagawa, A, Omura, T 2005 Transcapsidation and the conserved interactions of two major structural proteins of a pair of phytoreoviruses confirm the mechanism of assembly of the outer capsid layer J Mol Biol 345 229 237 PubMed CrossRef Modrof, J, Lymperopoulos, K, Roy, P 2005 Phosphorylation of bluetongue virus nonstructural protein 2 is essential for formation of viral inclusion bodies J Virol 79 10023 10031 PubMed CrossRef Nakagawa, A, Miyazaki, N, Taka, J, Naitow, H, Ogawa, A, Fujimoto, Z, Mizuno, H, Higashi, T, Watanabe, Y, Omura, T, Cheng, RH, Tsukihara, T 2003 The atomic structure of Rice dwarf virus reveals the self-assembly mechanism of component proteins Structure 11 1227 1238 PubMed CrossRef Omura, T, Yan, J 1999 Role of outer capsid proteins in transmission of Phytoreovirus by insect vectors Adv Virus Res 54 15 43 PubMed Owens, RJ, Limn, C, Roy, P 2004 Role of an arbovirus nonstructural protein in cellular pathogenesis and virus release J Virol 78 6649 6656 PubMed CrossRef Shikata, E 1981 Reoviruses Kurstak, E eds. Handbook of plant virus: infections and comparative diagnosis Elsevier/North-Holland Biomedical Press Amsterdam 423 451 Shirako, Y, Ehara, Y 1986 Comparison of the in vitro translation products of wilt-type and a deletion mutant of soil-borne wheat mosaic virus J Gen Virol 67 1237 1245 Suzuki, N, Hosokawa, D, Matsuura, Y, Kikuchi, A, Omura, T 1999 In vivo and in vitro phosphorylation of rice dwarf phytoreovirus Pns12 cytoplasmic nonstructural protein Arch Virol 144 1371 1380 PubMed CrossRef Suzuki, N, Sugawara, M, Kusano, T, Mori, H, Matsuura, Y 1994 Immunodetection of rice dwarf phytoreoviral proteins in both insect and plant hosts Virology 202 41 48 PubMed CrossRef Uyeda, I, Kudo, H, Yamada, N, Matsumura, T, Shikata, E 1990 Nucleotide sequence of rice dwarf virus genome segment 4 J Gen Virol 71 2217 2222 PubMed CrossRef Wei, T, Shimizu, T, Hagiwara, K, Kikuchi, A, Moriyasu, Y, Suzuki, N, Chen, H, Omura, T 2006 Pns12 protein of Rice dwarf virus is essential for formation of viroplasms and nucleation of viral-assembly complexes J Gen Virol 87 429 438 PubMed CrossRef Xu, H, Li, Y, Mao, ZJ, Chen, ZL 1998 Rice dwarf phytoreovirus segment S11 encodes a nucleic acid-binding protein Virology 240 267 272 PubMed CrossRef Zhong, B, Kikuchi, A, Moriyasu, Y, Higashi, T, Hagiwara, K, Omura, T 2003 A minor outer capsid protein, P9, of Rice dwarf virus Arch Virol 148 2275 2280 PubMed CrossRef