INDUCTION OF TETRAPLOID DNA CONTENT BY SIMIAN-VIRUS-40 IS DEPENDENT ON T-ANTIGEN FUNCTION IN THE G(2) PHASE OF THE CELL-CYCLE

Previous experiments with the simian virus 40 mutant tsA357R-K (tsA30) demonstrated a T-antigen function that is required for production of cells with a greater-than-G(2)-phase DNA content. In this study, tempe rature shift experiments indicated that the temperature-sensitive func tion of tsA357R-K, which is necessary for entry into the greater-than- G(2) phase, is not required in G(1) or S but must be supplied in the G (2) phase.