Efficiency of translation of messenger-RNA before and after fertilization in sea urchins.
Efficiency of translation of messenger-RNA before and after fertilization in sea urchins.
复制标题
海胆受精前后信使 RNA 的翻译效率。
DOI：
10.1016/0012-1606(69)90025-6
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发表时间：
1969
影响因子：
2.7
通讯作者：
T. Humphreys
中科院分区：
文献类型：
--
作者：
T. Humphreys
翻译效率（定义为每单位时间每个 mRNA 分子产生的蛋白质分子数量）在海胆卵受精时蛋白质合成加速之前和之后进行了比较。对蛋白质周转、核糖体上蛋白质合成的程度以及受精前后新合成蛋白质的大小分布的检查表明，蛋白质合成的加速涉及在 10 至 15 倍数量的活性核糖体上合成 10 至 15 倍的蛋白质分子。为了确定这些数量增加的活性核糖体是否与数量不变的 mRNA 分子更有效地相互作用，或者与数量增加的 mRNA 分子以相同的效率相互作用，比较了受精前后多核糖体的大小和核糖体在多核糖体上停留的时间。后一个时间间隔是通过测量新掺入的氨基酸保留在新生链中的平均时间和新生链的大小分布来确定的。新方法使海胆细胞的活性多核糖体产量基本上达到 100%，使这些测量成为可能。实验结果表明，卵和胚胎中的翻译效率相似。因此，蛋白质合成在受精时通过额外 mRNA 分子的翻译而加速。因此，蛋白质合成的翻译水平控制不能是细胞合成机器中某些成分（例如核糖体）活性的一般变化，而是必须特异性地控制特定的 mRNA 分子群的活性。
The efficiency of translation, defined as the number of protein molecules produced per mRNA molecule per unit time, was compared before and after the acceleration of protein synthesis which occurs upon fertilization of sea urchin eggs. Examination of protein turnover, extent of protein synthesis on ribosomes, and the size distribution of newly synthesized protein before and after fertilization showed that this acceleration of protein synthesis involved the synthesis of 10 to 15 times more protein molecules on 10 to 15 times as many active ribosomes. To determine whether these increased numbers of active ribosomes were interacting more efficiently with an unchanged number of mRNA molecules or at the same efficiency with an increased number of mRNA molecules, the size of the polysomes and the time a ribosome stayed on the polysomes was compared before and after fertilization. The latter time interval was determined by measuring the average time a newly incorporated amino acid remained in the nascent chains and the size distribution of the nascent chains. New methods giving essentially 100% yield of active polysomes from sea urchin cells made these measurements possible.The results of the experiments show that efficiency of translation is similar in egg and embryos. Protein synthesis, thus, is accelerated at fertilization by the translation of additional mRNA molecules. This translation level control of protein synthesis therefore cannot be a general change in activity of some component in the cellular synthetic machinery such as ribosomes, but must specifically control the activity of a defined population of mRNA molecules.