Effect of estradiol on the phosphorylation of rat liver ribosome proteins.

The effect of estradiol on phosphorylation with gamma-32P-ATP of ribosome proteins from polyribosome fraction, isolated from female rat liver is found out. Rats (180 g) used were: sham-operated, ovariectomized and treated after ovariectomy for 11 days with 20 micrograms 17 beta-estradiol-dipropionate per 100 g body weight. The estradiol deficiency after ovariectomy decreased phosphorylation, but the estrogenization of ovariectomized rats increases it twice. In vitro the hormone (1-2 mumol/l) [corrected] also stimulated ribosome protein phosphorylation. It is supposed that the hormone may take part in the regulation of protein synthesis in the translational region of the process.