pH changes associated with meiotic maturation in oocytes of Xenopus laevis.
pH changes associated with meiotic maturation in oocytes of Xenopus laevis.
复制标题
与非洲爪蟾卵母细胞减数分裂成熟相关的 pH 变化。
DOI：
10.1016/0012-1606(81)90267-0
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发表时间：
1981
影响因子：
2.7
通讯作者：
R. Steinhardt
中科院分区：
文献类型：
--
作者：
S. Lee;R. Steinhardt
在受精的海胆卵蛋白质合成的速率的pH值依赖控制表明，pH值可能有一个重要的作用，在受精的细胞活化。我们在异卵母细胞减数分裂成熟过程中寻找类似的细胞内pH值变化。卵母细胞的基础pH在7.4-7.8的范围内。较高的值主要是在最近激素刺激的动物的卵母细胞中发现的，这表明与这些卵母细胞的代谢升高相关。无论基础pH值如何，孕酮诱导的成熟卵母细胞平均碱化0.18 pH单位。在萌发囊泡破裂前不久开始，细胞内pH值下降到接近原始值。当通过注射“成熟促进因子”诱导成熟时，观察到相同的程序。如果细胞内pH被驱动为酸性，则成熟被延迟或抑制。它是在孕激素不存在的情况下由三甲胺诱导的，三甲胺是一种弱碱，可通过强制碱化作用发挥作用。然而，当防止净碱化时，仍然发生成熟。这些数据表明，在成熟过程中的碱化是一种形式的代谢“保险”，并可能有pH值依赖和pH值不依赖的成熟途径。有一些证据表明，pH值的变化与其他离子的运动有关。
The pH-dependent control of the rate of protein synthesis in the fertilized sea urchin egg has suggested that pH may have an important role in cell activation at fertilization. We looked for similar changes of intracellular pH during meiotic maturation of theXenopusoocyte. The basal pH of the oocyte is in the range 7.4–7.8. The higher values were found mostly in oocytes from animals with recent hormonal stimulation, suggesting a correlation with the elevated metabolism of such oocytes. Regardless of basal pH, progesterone-induced maturing oocytes alkalize an average of 0.18 pH unit. Beginning shortly before germinal vesicle breakdown, intracellular pH then decreases to near the original value. The same program is observed when maturation is induced by an injection of “maturation promoting factor.” Maturation is delayed or inhibited if intracellular pH is driven acidic. It is induced in the absence of progesterone by trimethylamine, a weak base which may act via an imposed alkalization. However, maturation still occurs when net alkalization is prevented. These data suggest that the alkalization during maturation is a form of metabolic “insurance” and that there may be both pH-dependent and pH-independent pathways for maturation. There is some evidence suggesting that pH changes are related to movement of other ions.