CatSper-null mutant spermatozoa are unable to ascend beyond the oviductal reservoir
CatSper-null mutant spermatozoa are unable to ascend beyond the oviductal reservoir
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DOI：
10.1071/rd08183
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发表时间：
2009-01-01
影响因子：
1.9
通讯作者：
Suarez, Susan S.
中科院分区：
文献类型：
--
作者：
Ho, Katharine;Wolff, Collin A.;Suarez, Susan S.
精子超活化的特征是高幅度，不对称的鞭毛弯曲，并需要穿透卵母细胞透明质膜。有人提出，超活化也使精子能够到达卵母细胞，协助逃逸输卵管精子库。为了验证这一假设，将CatSper缺失小鼠精子在输卵管中的行为与杂合子精子的行为进行了比较。CatSper（-/-）雄性不育，因为它们的精子不能过度活化，而CatSper（+/-）雄性的精子具有正常量的CatSper蛋白并且可以过度活化。雄性在排卵的早晨与野生型雌性交配。1或4小时后获得输卵管，并使用透射法检查精子的行为。在1小时，空突变精子仍然附着在他们的头部输卵管上皮在水库，而从杂合子精子脱离输卵管上皮后，执行深不对称鞭毛弯曲。在4 h时，在输卵管中仍观察到50至200个CatSper（+/-）精子;相比之下，仅发现1个CatSper（-/-）精子。CatSper（-/-）精子在未能及时与上皮分离后从输卵管中丢失，从而证明精子需要超活化才能上升到输卵管储库之外。
Sperm hyperactivation is characterised by high-amplitude, asymmetrical flagellar bending and is required to penetrate the oocyte zona pellucida. It was proposed that hyperactivation also enables spermatozoa to reach the oocyte by assisting escape from the oviductal sperm reservoir. To test this hypothesis, the behaviour of CatSper-null mouse spermatozoa in the oviduct was compared with that of spermatozoa from heterozygotes. CatSper(-/-) males are infertile because their spermatozoa fail to hyperactivate, whereas spermatozoa from CatSper(+/-) males have normal amounts of CatSper proteins and can hyperactivate. Males were mated with wild-type females on the morning of ovulation. Oviducts were obtained 1 or 4 h later, and behaviour of spermatozoa was examined using transillumination. At 1 h, null mutant spermatozoa remained attached by their heads to oviductal epithelium in the reservoir, whereas spermatozoa from heterozygotes detached from the oviductal epithelium after performing deep asymmetrical flagellar bends. At 4 h, 50 to 200 CatSper(+/-) spermatozoa were still seen in the oviducts; in contrast, only one CatSper(-/-) spermatozoon was found. CatSper(-/-) spermatozoa were lost from the oviducts after failing to detach from the epithelium in a timely manner, thus demonstrating that hyperactivation is required by spermatozoa to ascend beyond the oviductal reservoir.