Polypeptides of pneumonia virus of mice. I. Immunological cross-reactions and post-translational modifications.

A murine polyclonal antiserum and monoclonal antibodies have been employed to identify pneumonia virus of mice (PVM) polypeptides in infected cells and to study post-translational modifications. Immunoprecipitation experiments using a murine polyclonal antiserum and a monoclonal antibody directed against a 39K protein have established an antigenic relationship between two PVM proteins and the N and P proteins of human respiratory syncytial virus. Although 20 virus-specific polypeptides have been identified in lysates of infected cells, evidence is presented that some of these are related and that the number of unique polypeptides probably does not exceed 11 or 12. The phosphoproteins of PVM have a pattern of mobilities more like that of the recently described pneumovirus causing rhinotracheitis in turkeys than that of human or bovine respiratory syncytial virus.