title: Simian virus 40 mutants carrying two temperature-sensitive mutations.
abstract: Five temperature-sensitive mutants of simian virus 40 containing two temperature-sensitive mutations were isolated. The double mutant of the A and D complementation groups, like the D mutants, failed to complement by conventional complementation analysis and did not induce host DNA synthesis at 40 degrees C. However, under conditions that suppressed the D defect, the A:D double mutant expressed only the A defect. Thus, viral DNA replication dropped rapidly after this mutant was shifted from permissive to restrictive temperatures. The A:D double mutant failed to transfrom at the restrictive temperature when subconfluent Chinese hamster lung monolayers were used. Double mutants of A:B, A:C, and A:BC complementation groups, like their A parent, were defective in viral DNA replication, in the induction of host DNA synthesis and in the transformation of secondary Chinese hamster lung cells at the nonpermissive temperature.
mesh_terms: D000818:Animals; D002460:Cell Line; D002471:Cell Transformation, Neoplastic; D006224:Cricetinae; D004247:DNA / Q000096:biosynthesis; D004261:DNA Replication; D004279:DNA, Viral / Q000096:biosynthesis; D005816:Genetic Complementation Test; D006898:Hydroxylamines; D009153:Mutagens; D009154:Mutation; D013539:Simian virus 40 / Q000378:metabolism; D013696:Temperature
chemical_list: D004279:DNA, Viral; D006898:Hydroxylamines; D009153:Mutagens; D004247:DNA