Cellular ras activity and phospholipid metabolism.

Cellular ras activity has been neutralized in 3T3 cells by microinjection of a specific anti-ras monoclonal antibody. The injected antibody efficiently inhibited proliferation in cells treated with a phorbol ester and a calcium ionophore, or with prostaglandin F2 alpha. These treatments were designed to imitate the action of phospholipase C or of phospholipase A2. In addition, the highly efficient mitogenic potential of phosphatidic acid was inhibited by the injected antibody even more efficiently than was serum-induced proliferation. The close reliance of phospholipid-induced mitogenesis upon ras activity suggests that ras proteins are unlikely to function to control the action of a phospholipase.