title: Interference between virulent and avirulent strains of Sendai virus.
abstract: Interference between a virulent and an avirulent strain of Sendai virus was studied by plaque morphology and analysis of viral protein and RNA. On simultaneous infection a virulent, large plaque-forming strain (RL) was inhibited by an avirulent, small plaque-forming strain (RS). The interference was dose-dependent and decreased with u.v. irradiation of RS. One infectious particle was sufficient to induce the interference. SDS-polyacrylamide gel electrophoresis showed that interference was detectable in the synthesis of viral P protein; this was abolished when RS was u.v.-irradiated. Both growth and P protein synthesis of RL was restricted by superinfection with RS when this was done within 4 h after infection of RL, but the interference decreased gradually after this period and was not detectable after 8 h. Cycloheximide prolonged the period susceptible to superinfection by RS.
mesh_terms: D000818:Animals; D002642:Chick Embryo; D003513:Cycloheximide / Q000494:pharmacology; D006790:Host-Parasite Interactions; D010222:Parainfluenza Virus 1, Human / Q000254:growth & development* / Q000472:pathogenicity; D018184:Paramyxoviridae Infections / Q000382:microbiology; D012367:RNA, Viral / Q000235:genetics; D013997:Time Factors; D014466:Ultraviolet Rays; D014762:Viral Interference / Q000187:drug effects / Q000528:radiation effects; D014764:Viral Proteins / Q000096:biosynthesis; D014774:Virulence
chemical_list: D012367:RNA, Viral; D014764:Viral Proteins; D003513:Cycloheximide