Molecular cloning and characterization of the mRNA for cyclin from sea urchin eggs.
Molecular cloning and characterization of the mRNA for cyclin from sea urchin eggs.
复制标题
海胆卵细胞周期蛋白 mRNA 的分子克隆和表征。
作者：
J. Pines;T. Hunt
我们分离到了一个编码海胆细胞周期蛋白的cDNA克隆，并确定了其序列。它包含一个409个氨基酸的开放阅读框，与蛤细胞周期蛋白具有同源性。从该序列中转录的RNA在网织细胞裂解物中有效翻译，产生全长细胞周期蛋白。将纳克量的合成mRNA注射到爪蟾卵母细胞中，使其成熟速度比黄体酮处理更快。海胆周期蛋白在爪蟾卵母细胞成熟过程中经历了两次翻译后修饰。第一次发生在成熟成为环己亚胺抗性的时候，这时观察到细胞周期蛋白的分子量明显增加。第二次修饰涉及在白斑出现时周期蛋白的破坏，就像在自然环境中海胆胚胎分裂的中期/后期转变时发生的那样。
We have isolated a cDNA clone encoding sea urchin cyclin and determined its sequence. It contains a single open reading frame of 409 amino acids which shows homology with clam cyclins. RNA transcribed in vitro from this sequence was efficiently translated in reticulocyte lysates, yielding full‐length cyclin. Injection of nanogram amounts of this synthetic mRNA into Xenopus oocytes caused them to mature more rapidly than with progesterone treatment. The sea urchin cyclin underwent two posttranslational modifications in the Xenopus oocytes during maturation. The first occurred at about the time that maturation became cycloheximide‐resistant, when a small apparent increase in the molecular weight of cyclin was observed. The second modification involved destruction of the cyclin at about the time of white spot appearance, just as would have occurred at the metaphase/anaphase transition in the natural environment of a cleaving sea urchin embryo.