To study the morphogenesis and packaging of rice dwarf phytoreovirus (RDV), the interactions among multiple structural proteins were analysed using both the yeast two-hybrid system and far-Western blotting analysis. The following protein-protein interactions were observed. P3 (major core protein) bound to itself as well as to P7 (nucleic acid-binding protein) and P8 (major outer capsid protein). P7 bound to P1 (RNA-dependent RNA polymerase) and P8, in addition to P3. Based on these findings, we hypothesize that the core shell structure is based on P3-P3 interactions and that P7 has the ability to bind to multiple structural proteins as well as to genomic RNAs during viral particle assembly. Based on the observed protein-protein interactions and on computer-aided analysis of the numbers of structural proteins per particle, possible RDV assembly events are proposed.
AnzolaJ. V., XuZ., AsamizuT., NussD.1987; Segment-specific inverted repeats found adjacent to conserved terminal sequences in wound tumor virus genome and defective interfering RNAs. Proceedings of the National Academy of Sciences USA: 848301–8305
MuraoK., SudaN., UyedaI., IsogaiM., SugaH., YamadaN., KimuraI., ShikataE.1994; Genomic heterogeneity of rice dwarf phytoreovirus field isolates and nucleotide sequences of variants of genome segment 12. Journal of General Virology 75:1843–1848
NakashimaK., KakutaniT., MinobeY.1990; Sequence analysis and product assignment of segment 7 of the rice dwarf virus genome. Journal of General Virology 71:725–729
NibertM. L., SchiffL. A., FieldsB. N.1996; Reoviruses and their replication. In Fields Virology, 3rd edn. pp 1557–1596FieldsB. N., KnipeD. M., HowleyP. M. Edited by Philadelphia: Lippincott-Raven;
OmuraT., IshikawaK., HiranoH., UgakiM., MinobeY., TsuchizakiT., KatoH.1989; The outer capsid protein of rice dwarf virus is encoded by genome segment S8. Journal of General Virology 70:2759–2764
SuzukiN., SugawaraM., KusanoT., MoriH., MatsuuraY.1994; Immunodetection of rice dwarf phytoreoviral proteins in both insect and plant hosts. Virology 202:41–48
YeZ. S., BaltimoreD.1994; Binding of Vav to Gab2 through dimerization of Src homology 3 domains. Proceedings of the National Academy of Sciences USA: 9112629–12633