Influence of the deprivation of a single amino acid on cellular proliferation and survival in rat 3Y1 fibroblasts and their derivatives transformed by a wide variety of agents

Abstract

We compared proliferation and survival of various syngeneic transformed cell lines under conditions of depletion of 15 amino acids in Dulbecco-Eagle's medium. We used a normal fibroblast line 3Y1 and 22 transformed sublines of 3Y1 which had been induced by one of seven transforming agents--simian virus 40, mouse polyomavirus, adenovirus type 12, E1A gene of adenovirus type 12, cDNA of Harvey murine sarcoma virus, Rous sarcoma virus, or N-methyl-N'-nitro-N-nitrosoguanidine. Unlike other untransformed cells examined (mouse BALB/c-3T3 line, mouse NIH-3T3 line, and primary Fischer rat embryo fibroblasts), 3Y1 ceased to proliferate and accumulated in a viable state with a G1-phase DNA content under 14 singular deprivations of amino acid. None of the transformed 3Y1 lines completely arrested in the G1 phase of the cell cycle and each showed different levels of survival, depending on each transforming agent. As for transformed 3Y1 cells induced by a given virus or a given transforming gene, any one of the three sublines shared the same trend with respect to proliferation and survival. Transformed derivatives induced by N-methyl-N'-nitro-N-nitrosoguanidine showed almost the same trend in proliferation, but the patterns of survival were not uniform. Our observations suggest that the unique responses of 3Y1 to amino acid depletion are differently modified by different transforming agents.