Appearance of a new nucleosomal protein during differentiation of human leukemia (HL-60) cells.

A 60-kilodalton protein was identified in chromatin digested by micrococcal nuclease during retinoic acid-induced differentiation of human leukemia (HL-60) cells to mature-like granulocytes. The protein was not detected in a retinoic acid-resistant variant of the HL-60 cell line treated with retinoic acid, in HL-60 cells induced with dimethyl sulfoxide, or in normal human granulocytes. This protein may have an important role in the regulation of retinoic acid-induced leukemic cell differentiation.