Tissue specificity of histone phosphorylation.

The incorporation of (32)P-phosphate into histone fractions isolated from normal, hepatectomized, and Novikoff hepatoma-bearing rats was investigated. Varying degrees of phosphorylation were exhibited by different histone fractions. The phosphorylation of histones is tissue specific and appears to be correlated with metabolic cell functions, that is, it decreases with increasing mitotic activity of the cells.