Proteins of Friend leukemia cells. Comparison of hemoglobin-synthesizing and noninduced populations.

Proteins of Friend leukemia cells induced to form large amounts of hemoglobin by dimethylsulfoxide treatment were compared with proteins from noninduced cells by high resolution two-dimensional polyacrylamide gel electrophoresis. Approximately 98% of more than 500 proteins separated by this technique were qualitatively and quantitatively the same in both cell populations. Changes representing more than 50% of the control cell amount were detected in six non-histone chromosomal proteins, two nucleoplasmic proteins, and three cytoplasmic proteins. It is concluded that dimethylsulfoxide induces an extremely specific pattern of erythroid differentiation in these cells, which should be susceptible to detailed analysis. Comparison of protein patterns from Friend leukemia cells and HeLa cells revealed electrophoretic identity of approximately 20% of cytoplasmic proteins and 50% of non-histone chromosomal proteins.