ROUS-SARCOMA VIRUS GENOME STABLY INTEGRATED INTO MOUSE ASCITES SARCOMA-CELLS

The organization of RSV genes present in the mouse ascites sarcoma cells was analysed. The transformed cells kept in vivo and in vitro for a long time continued to contain intact RSV genome and the cellular integration site was unchanged. RSV was recovered by transfection of chick embryo cells with these cellular DNA. As these cells, especially in ascites form, grow very rapidly and it is easy to obtain a large amount of cells at a time, they are useful for further study as RSV-transformants derived from mouse cells.