Approach to the mechanism of fertilization and reproductive medicine

1.人精子顶体反应是通过细胞表膜孕酮受体(PR)参与精子受精能力、性激素的获得和对孕酮作用机制的分析而实现的。然而，膜受体的分子特性还不是很清楚。我们从人睾丸组织文库中克隆到孕激素受体基因的一个新亚型(称为“S亚型”)(PR亚型S基因，PR-S基因)，它由一个先前未知的5‘-未翻译序列和细胞内PR基因的第4-8外显子组成。PR-S基因编码与细胞内PR激素结合域的几乎全部部分相对应的蛋白质，称为“PR亚型S(PR-S)”。基因组克隆证实该信息的5‘端非翻译序列来源于一个新的外显子(称为“S”外显子)。此外，PR-S基因在…中的表达水平较高雌激素诱导Ca++内流进入精子细胞，这种作用是通过细胞表膜雌激素受体(ER，mo)的非基因组作用来估计的。我们从人睾丸c DNA文库中发现了雌激素受体基因的一个新亚型(称为“S”亚型)，它由一个5‘端未翻译的序列和细胞内ER基因的外显子4-8组成。结论：1.ERα-S基因编码的蛋白与细胞内ER激素结合域的几乎全部部分相对应，命名为“ERa亚型S(ERα-S)”，提示精子中可能表达的PR-S和ERα-S可能与细胞表膜类固醇激素受体有关。为分析卵母细胞胞浆内单精子注射(ICSI)后精子膜状态对卵母细胞激活率的影响，将人和小鼠精子分别注入小鼠卵母细胞，其中人精子注射后，用Triton X-100处理后，卵母细胞激活最快、效率最高，精子头部解聚后用Triton X-100处理。完整的精子激活卵母细胞的效果最差。当将小鼠精子注射到小鼠卵母细胞中时，无论注射前的精子处理类型如何，激活的卵母细胞内的卵母细胞激活率和精子头去凝集率都是相同的。较少

1. The participation to the sperm fertilizing ability acquisition of sex steroid hormones and analysis of mechanisms for the process/Progesterone has been demonstrated to induce the acrosome reaction in the human spermatozoon via the cell surface membrane progesterone receptor (PR). However, the molecular identity of the membrane receptor has not been clarified yet. We identified a novel isoform (termed "isoform S") of the progesterone receptor mRNA (PR isoform S mRNA ,PR-S mRNA) which consisted of a previously unidentified 5' -untranslated sequence and the exon 4-8 of the intracellular PR gene from the human testicular cDNA library. The PR-S mRNA could encode the protein corresponding to the almost entire part of the hormone binding domain of the intracellular PR, termed "PR isoform S (PR-S)". The 5' -untranslated sequence of the message was confirmed to be derived from a novel exon (termed "exon S") by the genomic cloning. Moreover, the expression level of the PR-S mRNA was higher in … More the spermatozoon than that in the uterine endometrium.Estrogen induces the influx of Ca++ into sperm cell, and this action is estimated with non-genomic action via the cell surface membrane estrogen receptor (ER), mo. We identified a novel isoform ( termed "isoform S" ) of the estrogen receptor mRNA (ER is form S mRNA ,Era -S mRNA) which consisted of a previously unidentified 5' -untranslated sequence and the exon 4-8 of the intracellular ER gene from the human testicular cDNA library. The ERα -S mRNA could encode the protein corresponding to the almost entire part of the hormone binding domain of the intracellular ER, termed "Era isoform S (ERα - S).These results implied that the PR-S and ERα -S which were possibility expressed in the spermatozoon might be related to the cell surface membrane steroid hormone receptors.2. Effect of sperm immobilization and demembranation on the oocyte activation rate in the mouseTo analyze the effect of the state of sperm membrane on the oocyte activation rate following intracytoplasmic sperm injection (ICSI), three types of human and mouse spermatozoa (intact, immobilized and Triton X-100 treated) were individually injected into mouse oocytes.Following human sperm injection, the fastest and the most efficient oocyte activation and sperm head decondensation occurred when the spermatozoa were treated with Triton X-100. Intact spermatozoa were the least effective in activating oocytes. When mouse spermatozoa were injected into mouse oocytes, the rates of oocyte activation and sperm head decondensation within activated oocytes were the same irrespective of the types of sperm treatments prior to injection. Less