Non-Histone Chromosomal Proteins of Chemically Transformed Neoplastic Cells in Tissue Culture

Chromatin proteins from control and dimethylnitrosamine-transformed baby hamster kidney cells were compared by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Our results indicate that non-histone chromosomal proteins from transformed cells contained protein components of low and intermediate electrophoretic mobility, which were deficient in normal cells. Comparison of the relative amount of incorporation of labeled amino acids into non-histone chromosomal proteins showed that protein components with a molecular weight of about 60,000 M.W. had a markedly increased labeling activity in the chemically transformed cells. These results suggest that changes in non-histone chromosomal proteins are associated with neoplastic transformation by chemical carcinogens.