Prominent increase in the amount of a cytosol protein in transformed fibroblasts and ascites hepatome cells

Analysis of cytosol proteins by sodium dodecyl sulfate polyacrylamide slab gel electrophoresis revealed a prominent increase in the amount of a cytosol protein with molecular weight of 88 000 in transformed human adult, human embryo, mouse adult, and hamster embryo fibroblasts as compared with normal fibroblasts. The cytosol protein with M r 88 000 is also increased in the cytosol of four kinds of rat ascites hepatoma cell as compared to normal and regenerating liver. The protein with M r 88 000 exists as one of the major cytosol proteins in transformed fibroblasts, hepatoma cells and HeLa cells, constituting 7–10% of total cytosol proteins. The data suggest that the cytosol protein with M r 88 000 is associated with certain growth characteristics of cells.