Mechanism of sperm differentiation in amphibians.

为了了解是什么决定了成熟精子中鞭毛的长度。比较了爪蟾和蝾螈精子细胞鞭毛生长的动力学。结果表明，蝾螈的生长速度和生长期比非洲爪蟾高2-3倍。两种动物的微管蛋白池的量均不随时间变化。在非洲爪蟾中，微管蛋白合成在第6天鞭毛生长停止时停止。对非洲爪蟾精子细胞顶体形成过程的相差显微镜观察和蛋白质合成抑制剂的应用表明，顶体囊泡的增大是由于小囊泡的合并，高尔基体前顶体小囊泡的形成不需要蛋白质合成，但囊泡的增大需要蛋白质合成。低渗处理后，次级精母细胞衍生的精子细胞发生融合，形成联顶体。测试了几种抑制剂，但没有效果。这些结果表明，蛋白质。RNA和碳水化合物的合成。细胞骨架营ATP生产。精子细胞中的Ca^<2+>和线粒体中的蛋白质合成在精子细胞核周围的线粒体组装中不起作用。在无细胞系统中。来自爪蟾肝脏的线粒体附着在精子细胞核上。而对肝细胞核和初级精母细胞则无影响。这些结果表明，爪蟾精子细胞核的变化是获得线粒体在核周围组装能力的原因。

In order to know what determines the flagellar length in mature sperm. The Kinetics of flagellar growth was compared between xenopus and newt spermatids. The results showed that the growth rate and growing period were higher and longer by 2-3 times in the newt than in xenopus. The amount of tubulin pool did not change with time in either species. In Xenopus, tubulin synthesis stopped on the 6th day when the flagellar growth ceased. Whereas in the newt, synthesis continued even on the 12th day.Phase contrast microscopic observation about acrosomal formation in Xenopus spermatids and application of protein synthesis inhibitors indicate that the enlargement of the vesicles is due to the coalescence of the small vesicles and the formation of small proacrosomal vesicles from Golgi appratus do not require protein synthesis but the enlargement of the vesicles do so. It was also found that hypotonic treatment of the spermatids derived from a secondary spermatocyte induces the cell fusion of the spermatids, which results in the formation of synacrosomes.To elucidate the mechanism of mitochondrial assembly around the nuclei of spermatids. Several inhibitors were tested but had no effect. These results indicate that protein. RNA and carbohydrate synthesis. cytoskeletons. cAMP. ATP production. Ca^<2+> in spermatids and protein synthesis in mitochondria play no role in mitochondrial assembly around the spermatid nuclei. In a cell-free system. mitochondria from Xenopus liver attached to the spermatid nuclei. Whereas they did not to the nuclei of liver or primary spermatocytes. These results indicate that the nuclear change is responsible for the acquisition of the ability of mitochondrial assembly around the nuclei in Xenopus spermatids.