Inositol 1,4,5-trisphosphate microinjection activates sea urchin eggs
Inositol 1,4,5-trisphosphate microinjection activates sea urchin eggs
复制标题
肌醇1,4,5-三磷酸显微注射激活海胆卵
作者：
M. Whitaker;R. Irvine
当精子在受精时激活海胆卵时，它会通过一种迄今为止未知的机制触发卵内储存的钙的释放1，2。随后细胞质钙浓度的瞬时增加是胚胎发育开始的刺激因素3，4。在这里，我们通过显微注射1，4，5-三磷酸肌醇（InsP 3）激活了海胆（Lytechinus pictus）卵，Berridge认为InsP 3可能是一种细胞内信使，其功能可能是从细胞内储存中释放钙6 -9。InsP 3被认为是由质膜磷脂酰肌醇4，5-二磷酸（PtdIns（4，5）P2）通过磷脂酶C10的酶水解产生的。最近，它已被证明，有一个大幅度增加的营业额的聚磷酸肌醇在海胆卵受精11。我们现在提出的初步证据表明，有一个钙刺激的故障PtdIns（4，5）P2在卵皮质。我们认为，正如显微注射InsP 3刺激细胞质钙的增加一样，受精时InsP 3的产生可能是导致卵子细胞内钙释放的原因。
When a sperm activates a sea urchin egg at fertilization, it triggers the release of calcium from a store within the egg by a hitherto unknown mechanism1,2. The ensuing transient increase in cytoplasmic calcium concentration is the stimulus for the beginning of embryonic development3,4. Here we have activated sea urchin (Lytechinus pictus) eggs by microinjecting inositol 1,4,5-trisphosphate (InsP3), a substance which Berridge5 has suggested may be an intracellular messenger whose probable function is to release calcium from intracellular stores6–9. It is thought that InsP3 is produced from plasma membrane phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2) via enzymatic hydrolysis by a phospholipase C10. Recently, it has been demonstrated that there is a substantial increase in the turnover of polyphosphoinositides in the sea urchin egg at fertilization11. We now present preliminary evidence that there is a calcium-stimulated breakdown of PtdIns(4,5)P2 in the egg cortex. We believe that, just as microinjecting InsP3 stimulates an increase in cytoplasmic calcium, the production of InsP3 at fertilization may be responsible for the release of calcium from the egg's intracellular store.
肌醇 1,4,5-三磷酸。
DOI：
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发表时间：
1984
期刊：
The Journal of biological chemistry
影响因子：
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作者：
Joseph,SK;Thomas,AP;Williams,RJ;Irvine,RF;Williamson,JR
通讯作者：
Williamson,JR