title: Characterization of a replication-defective temperature-sensitive mutant of Rous sarcoma virus.
abstract: A temperature-sensitive mutant (LA83) of Rous sarcoma virus defective both in the transformation and replication function has been isolated and partially characterized. Temperature-shift experiments showed that the defects in both the focus-forming and replication functions were late and continuous. The mutant LA83 was complemented by avian leukosis viruses. Complementation of LA83 replication was also observed with the glycoprotein-deletion mutant, Brian high-titer RSV(-) suggesting that the env gene in LA83 was not defective. At the nonpermissive temperature LA83-infected cells produced noninfectious particles with a yield of about 30%. The noninfectious particles had only about 3% of reverse-transcriptase activity as the infectious LA83 produced at the permissive temperature. However, the LA83 virions were as thermolabile as the parent wild-type PR-B virions.
mesh_terms: D000818:Animals; D001358:Avian Sarcoma Viruses / Q000235:genetics* / Q000302:isolation & purification; D002478:Cells, Cultured; D002642:Chick Embryo; D004261:DNA Replication; D004259:DNA-Directed DNA Polymerase / Q000378:metabolism; D005347:Fibroblasts; D009154:Mutation; D012194:RNA-Directed DNA Polymerase / Q000378:metabolism; D013696:Temperature; D014771:Virion / Q000235:genetics; D014779:Virus Replication
chemical_list: D012194:RNA-Directed DNA Polymerase; D004259:DNA-Directed DNA Polymerase