tRNA and aminoacyl-tRNA synthetases during differentiation and various functional states of the mammary gland

Regulation of tRNA

“…Such observations have been reported for reticulocytes (187,188), the silk glands of Bombyx mori (189)(190)(191), granulation tissue in rats (192,193), bovine lens tissue (194), and mammary glands (195). Moreover, sheep reticulocytes carrying different genetic alleles for hemoglobin ~/chains contain different levels of tRNA TM and tRNðt in accordance with the amino acid compositions of thẽ chain being synthesized (196).…”

“…Moreover, sheep reticulocytes carrying different genetic alleles for hemoglobin ~/chains contain different levels of tRNA TM and tRNðt in accordance with the amino acid compositions of thẽ chain being synthesized (196). Occasionally, alterations in isoaccepting tRNA patterns accompany these adaptations (190,193,195,196).…”

“…Such increases in tRNA may vary among the different tRNA species. Alteration in the tRNAO~u/tRNÃ ratio, as well as appearance, on MASA column chromatography, of a new tRNA r~u species has been reported during in vivo differentiation of bovine mammary glands (195). Alteration…”

Ribosomes

“…At the same time, the cell can selectively change the efficacy of expression (translation) of a weakly expressed mRNA through adaptation of isoacceptor tRNA concentrations to codon frequencies in the particular mRNA (Elska et al, 1971;Garel, 1976). At the same time, the cell can selectively change the efficacy of expression (translation) of a weakly expressed mRNA through adaptation of isoacceptor tRNA concentrations to codon frequencies in the particular mRNA (Elska et al, 1971;Garel, 1976).…”

Effect of anoxia and Polyscias filicifolia Bailey biomass tincture on the activity of tRNA and aminoacyl-tRNA synthetases in isolated pig heart

“…Preparations of total aminoacyl-tRNA synthetases were isolated by the DEAE-cellulose column chromatography of pig heart postribosomal supernatant as described in (22). Acceptor activities of tRNA in total tRNA preparations isolated from the control and anoxic myocardium were measured and renaturation of inactive tRNA conformers was performed as described in (23).…”