Mitogenic effects of the proto-oncogene and oncogene forms of c-H-ras DNA in human diploid fibroblasts

Nuclear microinjection of c-H-ras DNA induced DNA synthesis in reversibly nonproliferating quiescent human cells. The proto-oncogene and oncogene forms were equally effective inducers. In contrast, c-H-ras DNA either alone or in combination with the adenovirus E1A gene did not cause terminally nondividing senescent cells to synthesize DNA.