RT Journal Article SR Electronic(1) A1 Eichwald, Catherine A1 Rodriguez, José Francisco A1 Burrone, Oscar R.YR 2004 T1 Characterization of rotavirus NSP2/NSP5 interactions and the dynamics of viroplasm formation JF Journal of General Virology, VO 85 IS 3 SP 625 OP 634 DO https://doi.org/10.1099/vir.0.19611-0 PB Microbiology Society, SN 1465-2099, AB Viroplasms are discrete structures formed in the cytoplasm of rotavirus-infected cells and constitute the replication machinery of the virus. The non-structural proteins NSP2 and NSP5 localize in viroplasms together with other viral proteins, including the polymerase VP1, VP3 and the main inner-core protein, VP2. NSP2 and NSP5 interact with each other, activating NSP5 hyperphosphorylation and the formation of viroplasm-like structures (VLSs). We have used NSP2 and NSP5 fused to the enhanced green fluorescent protein (EGFP) to investigate the localization of both proteins within viroplasms in virus-infected cells, as well as the dynamics of viroplasm formation. The number of viroplasms was shown first to increase and then to decrease with time post-infection, while the area of each one increased, suggesting the occurrence of fusions. The interaction between NSP2 and a series of NSP5 mutants was investigated using two different assays, a yeast two-hybrid system and an in vivo binding/immunoprecipitation assay. Both methods gave comparable results, indicating that the N-terminal region (33 aa) as well as the C-terminal part (aa 131–198) of NSP5 are required for binding to NSP2. When fused to the N and C terminus of EGFP, respectively, these two regions were able to confer the ability to localize in the viroplasm and to form VLSs with NSP2., UL https://www.microbiologyresearch.org/content/journal/jgv/10.1099/vir.0.19611-0