Estrogen-induced variation of lysine transfer ribonucleic acid isoacceptors in chicken liver

Abstract

The effect of estrogenization on aminoacyl-tRNA formation in unfractionated chicken liver tRNA preparations from actively laying hens and diethylstilbestrol-treated immature hens and cocks was studied. 1. 1. Laying hen liver tRNA prepared by a pH 5 precipitation procedure contained approx. 25 % more lysyl-tRNA per A 260 unit of tRNA, as measured by enzymatic aminoacylation, than equivalent preparations from immature hens and cocks. 2. 2. Estrogenization of 10–14 week old immature birds by diethylstilbestrol injection also resulted in an approx. 25 % increase in lysyl-tRNA 65 h after treatment. This increase was independent of the sex of the bird and whether the synthetase preparation was made from control or diethylstilbestrol-treated birds. tRNA prepared by a detergent-phenol procedure gave results similar to the pH 5-precipitated tRNA. 3. 3. Increases in seryl-tRNA (18.7 %) and arginyl-tRNA (0.4 %) were noted in liver tRNA preparations from diethylstilbestrol-treated birds. No changes were observed for glutamyl-tRNA and phenylalanyl-tRNA. 4. 4. Co-chromatography of control and diethylstilbestrol-treated chicken liver lysyl-tRNA on methylated albumin-kieselguhr columns resolved two species of lysyl-tRNA. A marked increase in lysyl-tRNA (Species I) relative to lysyl-tRNA (Species II) was noted in the diethylstilbestrol-treated chicken liver preparations.