【摘要】 从不同年龄（20天,30天,1年）的小白鼠全脑制得细胞质混合氨酰tRNA合成酶。用异源体系（即用酵母tRNA和小白鼠全脑氨酰tRNA合成酶）测定了氨酰tRNA合成酶分别载运³H标记的Asp、Gly、Glu、Lys和Ala的活力。结果表明除未检出tRNA^Glu的合成酶活力外,对其余四种氨基酸都有明显的活力,特别是年龄20天小白鼠的氨酰tRNA合成酶对³H-Gly具有高达35％的载运活力。对³H-Gly、³H-Lys和³H-Ala的载运活力有随增龄而下降的趋势,但对³H-Asp的载运活力则随年龄增长而增高。更多还原

【Abstract】 Results in this paper indicate that the aminoacyl-tRNA synthetases, prepared from brain tissues of mouse at different age have different charging activities to tRNAs of aspartic acid, glycine, lysine and alanine but no detectable- activity to charge glutamic acid tRNA in a heterologous assay system containing yeast tRNA and mouse aminoacyl-tRNA synthetase.Aminoacyl-tRNA synthetase activities related to glycine lysine and alanine are tending to decrease with increase in age, but the age-related charge in activtty is just reversed in the case of aspartic acid tRNA synthetase.更多还原