October 6, 2020

Early steps in reovirus replication

Conformational change in a reovirus surface protein modulate the virus’s attachment to host cells, Vanderbilt researchers have found.

by Leigh MacMillan

Reoviruses — a family of viruses that infect most mammals — use a protein called sigma1 to attach to host cells. Sigma1 undergoes a conformational change from a compact form to an extended form during virus cell entry and uncoating, but the functional significance of this change is unknown. 

Kristen Ogden, PhD, and colleagues engineered changes in various domains of sigma1 to restrict the protein’s conformational mobility. 

They report in the Journal of Virology that a change cross-linking the receptor-binding domain yielded a virus that replicates faster and forms larger plaques compared to the parental virus. Functional assays showed the change did not affect virus uncoating or transcription of viral genetic material. 

The findings suggest that the conformational flexibility of sigma1 modulates the efficiency of reovirus host cell attachment. The authors note that many viruses likely employ conformational rearrangements of outer proteins to modulate the early steps of viral replication.

This research was supported by the National Institutes of Health (grant AI118887).