Transfer of thymidine kinase to thymidine kinaseless L cells by infection with ultraviolet-irradiated herpes simplex virus.
L cells lacking thymidine kinase (TK) activity (Ltk(-) cells) have been stably transformed to a TK-positive phenotype by infection with ultraviolet-irradiated herpes simplex virus (HSV-UV). The highest frequency of the Ltk(-) to Ltk(+) transformation observed in these experiments was approximately 10(-3), whereas no measurable transformation was observed (less than 10(-8)) in the absence of HSV-UV infection. Cell lines of HSV-transformed Ltk(+) cell lines contain 7 to 24 times as much TK activity as do the parental Ltk(-) cells, and they have been maintained in culture for a period exceeding 8 months. The kinetics of thermal inactivation of the TK activity derived from an Ltk(+) HSV-transformed cell line and the TK activity from Ltk(-) cells lytically infected with infectious HSV are similar. Both of these TK activities are much more thermolabile than the TK activity present in wild-type L cells. A mutant strain of HSV which does not induce TK activity during lytic infection does not cause the Ltk(-) to Ltk(+) transformation. These data suggest that either an HSV TK gene has been transferred to Ltk(-) cells or that an HSV gene product has caused the expression of a previously repressed cellular enzyme.
D000818:Animals; D001973:Bromodeoxyuridine / Q000494:pharmacology; D002474:Cell-Free System; D003470:Culture Media; D003588:Cytopathogenic Effect, Viral; D003851:Deoxyribonucleases; D006358:Hot Temperature; D007106:Immune Sera; D007739:L Cells / Q000201:enzymology*; D009154:Mutation; D011817:Rabbits; D018139:Simplexvirus / Q000472:pathogenicity / Q000528:radiation effects; D013936:Thymidine / Q000378:metabolism; D013937:Thymidine Kinase / Q000378:metabolism*; D014170:Transformation, Genetic; D014316:Tritium; D014466:Ultraviolet Rays
D003470:Culture Media; D007106:Immune Sera; D014316:Tritium; D013937:Thymidine Kinase; D003851:Deoxyribonucleases; D001973:Bromodeoxyuridine; D013936:Thymidine