Reinitiation of cellular DNA synthesis in BrdU-selected nondividing senescent WI-38 cells by simian virus 40 infection.
Bromodeoxyuridine-selected nondividing senescent WI-38 cells were stimulated to synthesize DNA, as evidenced by incorporation of [3H]thymidine into nuclei of senescent cells, after infection with simian virus 40 (SV40). Cellular DNA synthesis was confirmed by DNA-DNA hybridization experiments and the use of temperature-sensitive A gene mutants. The DNA synthesis was, at least in part, semiconservative, as microdensitometry of Feulgen-stained nuclei revealed increased DNA content in a large fraction of the cells in the infected population. Thus, senescent cells retain the capacity to replicate their DNA, despite their intrinsic inability to initiate DNA synthesis.
D000818:Animals; D000952:Antigens, Polyomavirus Transforming; D000957:Antigens, Viral, Tumor / Q000032:analysis; D001973:Bromodeoxyuridine / Q000494:pharmacology*; D002470:Cell Survival; D002472:Cell Transformation, Viral; D004261:DNA Replication / Q000187:drug effects*; D003720:Densitometry; D005455:Fluorescent Antibody Technique; D009693:Nucleic Acid Hybridization; D009856:Oncogene Proteins, Viral / Q000032:analysis; D051381:Rats; D013539:Simian virus 40; D013696:Temperature; D013936:Thymidine / Q000378:metabolism
D000952:Antigens, Polyomavirus Transforming; D000957:Antigens, Viral, Tumor; D009856:Oncogene Proteins, Viral; D001973:Bromodeoxyuridine; D013936:Thymidine