Identification of a glucocorticoid-sensitive histone protein from mouse fibroblast nuclei

Abstract The acid-soluble proteins from mouse fibroblast nuclei show a typical elution profile for histone proteins on Bio-Rex 70 columns. Glucocorticoid treatment of cells growing in vitro decreases labeled amino acid incorporation into one specific histone region, corresponding to a peak of a lysinerich histone. The single histone affected is present in only small amounts in the cell; it normally represents about 6% of the H 1 protein, and less than 1% of the total histones. As measured by total protein nitrogen of the affected peak, glucocorticoid inhibition of this protein is first apparent between one and two hours after the start of steroid treatment.