Expression of varicella-zoster virus-related antigens in biochemically transformed cells

L(O)cl 3 and L(K)cl 1 cells, biochemically transformed by varicella-zoster virus (VZV), were labelled with L-[35S]methionine and [32P]orthophosphate. Cell extracts were immunoprecipitated with anti-VZV monkey serum and analysed by SDS-polyacrylamide gel electrophoresis. Four polypeptides of apparent mol. wt. 135000 (135K), 48K, 44K and 35K were detected in the L-[35S]methionine-labelled extracts, and, of these, the 35K band showed marked intensity. However, this band was not detected in extracts from cells infected with a VZV tk- strain (Kanno strain). Also, the 35K polypeptide showed very low intensity when immunoprecipitated from extracts of transformed cells grown in non-selective (NS) medium, i.e. cells that had a very low thymidine kinase (tk) activity. In the case of [32P]orthophosphate-labelled cells, polypeptides of apparent mol. wt. 180K, 81K, 48K, 44K and 37K were obtained. In both instances, the 44K polypeptide was not immunoprecipitated from L(K)cl 1 cell extracts. From our data it is postulated that the expression of the 35K polypeptide is correlated with the VZV-specific tk activity of the cells.