6533b835fe1ef96bd12a0125

RESEARCH PRODUCT

Dynamics and interactions of parvoviral NS1 protein in the nucleus

subject

description

Summary Nuclear positioning and dynamic interactions of viral proteins with nuclear substructures play essen- tial roles during infection with DNA viruses. Visual- ization of the intranuclear interactions and motility of the parvovirus replication protein (NS1) in living cells gives insight into specific parvovirus protein- cellular structure interactions. Confocal analysis of highly synchronized infected Norden Laboratory Feline Kidney cells showed accumulation of nuclear NS1 in discrete interchromosomal foci. NS1 fused with enhanced yellow fluorescence protein (NS1- EYFP) provided a marker in live cells for dynamics of NS1 traced by photobleaching techniques. Fluo- rescence Recovery after Photobleaching suggested that the NS1 protein is not freely diffusing but undergoes transient interactions with nuclear com- partments. Fluorescence Loss in Photobleaching demonstrated for the first time the shuttling of a par- voviral protein between the nucleus and the cyto- plasm as assayed with NS1-EYFP. Finally, time-lapse imaging of infected cells revealed that the intra- nuclear distribution of NS1-EYFP evolves dramati- cally starting from the formation of NS1 foci and proceeding to a homogenous distribution extending throughout the nucleus.