Cell-biological analyses on the mechanism of infertility induced in gene knockout mice and sperm preparation leading to oocyte activation.

主要研究结果如下：1.基因敲除小鼠不孕症的发生机制。1)GOPC-/-精子(无顶体头部)的能力与MN13的储存程度成正比，而与DNA染色质的破坏程度无关。这有力地提示了精子头中MN13分子存储的重要性。2)GC/-/-精子不育(畸精症)不能反映MN13的保存程度。3)Caf-1-/-精子不育(少弱畸形精子症)本质上是支持细胞-生殖细胞相互作用失败所致。这一失败是由于支持细胞中维甲酸X受体β的功能障碍，导致精子发生在早期伸长精子期停止。3)Brek-/-不育症的主要原因是早熟生殖细胞的凋亡和早期伸长精子细胞外质特化的不良形成。2.精子准备、启动，导致卵母细胞激活。1)免疫球蛋白超家族蛋白Begeging和MC31/CE9在精子发生顶体反应后被修饰，使其分子质量降低。这是由于脱糖作用所致。2)对顶体内转运途径和MN9/Equatorin行为的分析表明，MN9/Equatorin定位于顶体内膜，由于赤道段的染色能力，可作为评价顶体反应中顶体状态的稳定标志物。3)由于顶体后区域的染色能力，核膜周膜蛋白MN13也是在精卵融合水平上评价精子状态的稳定标记物。3.精子成熟相关的油菜素。肉碱依赖的精子在附睾头的成熟依赖于肉碱转运体OCTN2在附睾头的表达。

The major results obtained were as follows.1.The mechanisms of the infertility found in gene knockout mice. 1) Inability of GOPC -/- sperm (acrosome-less head) paralleled to the degree of MN13 storage but not to the disruption degree of DNA chromatin. This strongly suggests the importance of MN13 molecule storage in ther sperm head. 2) The infertility of Gc/ -/- sperm (teratozoospermia) did not reflect the degree of MN13 storage. 3) The infertility of Caf-1 -/- sperm (oligo-astheno-teratozoospermia) was essentially due to the failure between Sertoli cell-germ cell interaction. This failure was mediated by the dysfunction of retinoid X receptor beta in Sertoli cells, causing spermiogenesis arrest at early elongating spermatic stage. 3) The infertility of BREK -/- was essentially due to apoptosis in premature germ cells and ill formation of ectoplasmic specialization at early elongating spermatids. 2.Sperm preparation, priming, leading to oocyte activation. 1) Immunoglobulin superfamily proteins, besieging and MC31 /CE9, were posttestically modified, reducing the molecular weight after the acrosome reaction. This was due to deglycosylation. 2) Analyses to detect the intracrosomla transport route to developing acrosomal membranes and the behavior of MN9/equatorin indicated that MN9/equatorin locates to the inner acrosomal membrane and becomes a stable marker to evaluate the acrosome status during acrosome reaction because of the staining ability of the equatorial segment. 3) Perinuclear theca protein MN13 was also a stable marker to evaluate the sperm status at the level of sperm-egg fusion because of the staining ability of the postacrosomal region. 3.Sperm maturation-related camitine. Carnitine-dependent sperm maturation in the epididymis was found to depend on the expression of carnitine transporter OCTN2 in the dital caput epididymis.