Our model suggests that the rhabdovirus M protein regulates the transition from replication to virion assembly and renders the infected cells nonpermissive for secondary infections.<b>IMPORTANCE</b> Superinfection exclusion (SIE) is a widespread phenomenon in which an established virus infection prevents reinfection by closely related viruses.
These results indicate that M protein mutant viruses are superior candidates as oncolytic viruses for therapies of prostate tumors, but future strategies for use of VSV will require testing individual tumors for their susceptibility to virus infection.