info:ar-repo/semantics/artículo
Interaction of Mal de Río Cuarto virus (Fijivirus genus) proteins and identification of putative factors determining viroplasm formation and decay
Fecha
2017Autor
Llauger, Gabriela
De Haro, Luis Alejandro
Alfonso, Victoria
Del Vas, Mariana
Resumen
Mal de Río Cuarto virus (MRCV) is a member of the Fijivirus genus, within the Reoviridae family, that repli-cates and assembles in cytoplasmic inclusion bodies called viroplasms. In this study, we investigatedinteractions between ten MRCV proteins by yeast two-hybrid (Y2H) assays and identified interactionsof non-structural proteins P6/P6, P9-2/P9-2 and P6/P9-1. P9-1 and P6 are the major and minor compo-nents of the viroplasms respectively, whereas P9-2 is an N-glycosylated membrane protein of unknownfunction. Interactions involving P6 and P9-1 were confirmed by bimolecular fluorescence complementa-tion (BiFC) in rice protoplasts. We demonstrated that a region including a predicted coiled-coil domainwithin the C-terminal moiety of P6 was necessary for P6/P6 and P6/P9-1 interactions. In turn, a shortC-terminal arm was necessary for the previously reported P9-1 self-interaction. Transient expression ofthese proteins by agroinfiltration of Nicotiana benthamiana leaves showed very low accumulation levelsand further in silico analyses allowed us to identify conserved PEST degradation sequences [rich in pro-line (P), glutamic acid (E), serine (S), and threonine (T)] within P6 and P9-1. The removal of these PESTsequences resulted in a significant increase of the accumulation of both proteins.