The Norovirus NS3 Protein Is a Dynamic Lipid- and Microtubule-Associated Protein Involved in Viral RNA Replication.

Abstract

Many mechanisms involved in the replication of norovirus still remain unclear, including the role for the NS3 protein, one of seven nonstructural viral proteins, which remains to be elucidated. This study reveals that murine norovirus (MNV) NS3 is intimately associated with the viral replication complex and dsRNA. We observed that the NS3 proteins of both MNV and Norwalk virus (NV) induce prominent vesicular structures and that this formation is dependent on microtubules and cellular cholesterol. Thus, this study contributes to our understanding of protein function within different Norovirus genogroups and expands a growing knowledge base on the interaction between positive-strand RNA [(+)RNA] viruses and cellular membranes that contribute to the biogenesis of virus-induced membrane organelles. This study contributes to our understanding of viral protein function and the ability of a viral protein to recruit specific cellular organelles and lipids that enable replication.