Coat proteins, host factors and plant viral replication

It was once believed that the sole biological function of viral coat protein (CP) is to encapsidate the viral genome, protecting it from degradation. The past several decades have witnessed a shift in this paradigm towards recognizing CPs as multifunctional proteins involved in almost every stage of the viral infection cycle. Such functional diversity is achieved via specific CP interactions with viral and host components in the infected cell. Different CP functions are tightly regulated both temporally and spatially through a variety of mechanisms including post-translational modifications and competing interactions. In the present review, we summarize the non-structural functions of plant viral CPs, placing special emphasis on their roles in viral genome replication and translation.

► Plant viral coat proteins (CPs) represent multifunctional proteins involved in nearly every stage of the viral infection cycle. ► Interactions between CPs and viral RNA may lead to either inhibition or enhancement of viral gene expression. ► Changes in CP levels regulate the progression of viral infection cycle from genome replication/translation to virion assembly.