title: Temperature-sensitive mutants of adenovirus type 12 defective in viral DNA synthesis.
abstract: Ten temperature-sensitive (ts) mutants of adenovirus type 12 which produce plaques at 31 but not at 38.5 C have been isolated after mutagenesis with nitrosoguanidine or nitrous acid. The mutants have been classified into six separate complementation groups. DNA-DNA hybridizations have shown that at 38.5 C the ts 401 and 406 mutants of groups B and E, respectively, synthesized less than 10% of the normal level of viral DNA. The two mutants were also defective in the production of late proteins at the nonpermissive temperature, as shown by fluorescent-antibody tests and analysis by sodium dodecyl sulfatepolyacrylamide gel electrophoresis. Genetic recombination between the ts viruses 401 and 406 has been demonstrated; the recombination frequency for the wild-type virus production was 17.7%. Both mutants induced an increase in thymidine kinase activity at 38.5 C. Moreover, the two viral DNA-defective mutants shut off host DNA synthesis at the restrictive temperature. It is striking that at 38.5 C ts virus 401 transformed two to eight times more hamster cells than the wild-type virus, whereas ts virus 406 transformed at a frequency similar to the wild-type virus.
mesh_terms: D000256:Adenoviridae / Q000187:drug effects / Q000254:growth & development; D002460:Cell Line; D004279:DNA, Viral / Q000096:biosynthesis*; D003673:Defective Viruses / Q000254:growth & development; D005816:Genetic Complementation Test; D006801:Humans; D066298:In Vitro Techniques; D007668:Kidney / Q000196:embryology; D009153:Mutagens; D009154:Mutation; D009573:Nitrites; D009604:Nitrosoguanidines; D009693:Nucleic Acid Hybridization; D011995:Recombination, Genetic; D013696:Temperature; D013936:Thymidine; D013937:Thymidine Kinase / Q000378:metabolism; D014316:Tritium; D014779:Virus Replication
chemical_list: D004279:DNA, Viral; D009153:Mutagens; D009573:Nitrites; D009604:Nitrosoguanidines; D014316:Tritium; D013937:Thymidine Kinase; D013936:Thymidine