RSV-transformed mammalian cells: an analysis of RNAs specific for exogenous and endogenous viruses.

A marked decrease in expression of RSV-specific sequences was observed in cryptovirogenic RSV-transformed RVP3 murine cells during passaging. Simultaneously an increase in expression of sequences specific for C-type murine viruses was observed both in these cells and other RSV-transformed murine cells. No activation of C-type viral genome was detected in spontaneous murine lung tumors and in methylcholanthrene-induced murine tumors. Four types of virus specific RNAs were found in XC cells: the 30--35 S, the 26--28 S, the 21--23 S and the 15--18 S type. The 9--14 S RNA was the dominant species of RSV-specific RNA in TWERC cells.