Thyrotropin Stimulation of the Phosphorylation of Serine in the N‐Terminal Region of Thyroid H1 Histones

Abstract
The analysis of thyroid nuclear proteins by polyacrylamide gel electrophoresis has demonstrated that thyrotropin and dibutyryl adenosine 3′:5′‐monophosphate stimulate specifically the phosphorylation of H1 histones in an intact cell system.This effect does not require new protein synthesis and implicates the phosphorylation of serine residue(s) situated in the N‐terminal part of H1 histones.