Translation of maternal messenger ribonucleoprotein particles from sea urchin in a cell-free system from unfertilized eggs and product analysis.
Translation of maternal messenger ribonucleoprotein particles from sea urchin in a cell-free system from unfertilized eggs and product analysis.
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在无细胞系统中从未受精卵中翻译来自海胆的母体信使核糖核蛋白颗粒和产品分析。
DOI：
10.1016/0012-1606(78)90246-4
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发表时间：
1978
影响因子：
2.7
通讯作者：
J. Ilan
中科院分区：
文献类型：
--
作者：
J. Ilan
从未受精的海胆卵的postribosomal上清液中分离母体mRNP颗粒。它们在来自未受精卵的无细胞系统中翻译。这些颗粒的翻译需要12 mMMgCl2的存在，这被认为是非常高的。当mRNP颗粒在来自桑椹胚的无细胞系统中翻译时，观察到相同的高Mg 2+需求。相比之下，从mRNP颗粒提取的mRNA在3 mMMgCl 2下翻译。已知该Mg2+浓度对于mRNA翻译的起始是最佳的。同样，在无细胞系统中，兔珠蛋白mRNA在3 mMMgCl 2时被忠实地翻译成α和β珠蛋白链，但在12 mMMgCl 2时则不然。在两种凝胶系统中检查由mRNP或由mRNP衍生的mRNA指导的翻译产物，发现其非常相似。在这两种情况下，组蛋白被确定为翻译产物的一部分。这表明在高Mg 2+中mRNP的翻译不是由于这些颗粒与核糖体的非特异性结合。来自鸡蛋的无细胞系统中的珠蛋白合成的速率是相媲美的桑椹胚核糖体和翻译的珠蛋白与小鼠肝脏和网织红细胞核糖体的报告，表明未受精的海胆卵核糖体不具有翻译抑制剂，并没有缺陷的mRNA翻译的起始因子可以解释在未受精的海胆卵的蛋白质合成率低。
Maternal mRNP particles were isolated from the postribosomal supernatant fluid of unfertilized sea urchin eggs. They were translated in a cell-free system derived from unfertilized eggs. The translation of these particles required the presence of 12 mMMgCl2, which is considered very high. The same high Mg2+requirement was observed when mRNP particles were translated in a cell-free system from morula embryos. In contrast, mRNA extracted from mRNP particles is translated at 3 mMMgCl2. This concentration of Mg2+is known to be optimal for initiation of mRNA translation. Likewise, a rabbit globin mRNA is faithfully translated into α and β globin chains in a cell-free system from eggs at 3, but not at 12, mMMgCl2. The translational products directed by mRNP or by mRNA derived from mRNP were examined in two gel systems and were found to be very similar. In both cases, histones were identified as part of the translational product. This indicated that the translation of mRNP in high Mg2+is not due to nonspecific binding of these particles to ribosomes. The rates of globin synthesis in a cell-free system derived from eggs is comparable to that of morula ribosomes and to that reported for translation of globin with mouse liver and reticulocyte ribosomes, indicating that unfertilized sea urchin egg ribosomes do not possess a translational inhibitor and that no deficiency in initiation factors for mRNA translation could explain the low rate of protein synthesis in unfertilized sea urchin eggs.