Alteration of vesicular stomatitis virus L and NS proteins by uv irradiation: Implications for the mechanism of host cell shut-off

When purified, [ 35S]methionine-labeled vesicular stornatitis virus (VSV) was exposed to ultraviolet light, an irradiation-induced change in the viral proteins was detected by SDS-polyacrylamide gel electrophoresis and immunoblotting. With dose of uv irradiation in the same range as that required to inactivate VSV leader RNA, a loss occurred in the bands corresponding to the L and NS proteins concomitant with the appearance of several new bands of radioactivity throughout the gel. This alteration of viral proteins correlated with the loss of ability of the virus to inhibit host macromolecular synthesis. In light of these results, the role that has been ascribed to the VSV leader RNA in VSV-mediated host shut-off needs to be reevaluated.