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Sperm-Egg Interactions

精子与卵子的相互作用

基本信息

批准号：
61440006
负责人：
HOSHI Motonori
金额：
$ 18.43万
依托单位：
Tokyo Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (A)
财政年份：
1986
资助国家：
日本
起止时间：
1986 至 1988
项目状态：
已结题

项目摘要

Molecular mechanisms of the acrosome reaction, sperm-binding to and sperm penteration through the vitelline coat, and membrane fusion were studied by using echinoderms and ascidians.Starfish egg jelly contains a sulfated glycoprotein (ARIS), a high-mannose glycoprotein with saccharide chains having 0-3 glucose residues at the non-reducing termini, sulfated steroidal saponins including Co-ARIS I, II, and III, and oligopeptides including SAP. In alkaline or high Ca^<++> sea water, ARIS induces the acrosome reaction. In normal sea water, a combination of ARIS and Co-ARIS induces the acrosome reaction whithout incresing PH_i.Three novel ceramide dihexosides; melibiosyl,gentibiosyl and from echinoderm gametes. Their possible roles in the acrosome reaction and fusion of sperm and egg plasma membranes are under investigation.N-Acetylhexosaminidase, the most potent glycosidase in the sperm of Halocynthia roretzi, was purified and characterized. The second potent was -L-fucosidase that seems to serve as vitelline coat-binding protein. Sperm receptor in the vitelline coat was suggested to have terminal L-Fuc, D-GalNAc and D-GlcNAc. Indeed, major N-glycoside chains of the vitelline coat have such structures. A 60K protein was suggested to be a physiological substrate of vitelline coat lysin(s).During the course of oocyte maturation triggered by 1-methyl-adenine in Asterina, a 39K Gi protein and a trypsin-type protease of high substrate specificity participate in the steps befor and after MPF formation, respectively.

用棘皮动物和海鞘动物研究了顶体反应、精子结合和穿卵以及膜融合的分子机制。海星卵冻含有一种硫酸化糖蛋白（阿里斯）、一种糖链在非还原末端有0-3个葡萄糖残基的高甘露糖糖蛋白、硫酸化甾体皂苷（包括Co-阿里斯I、II和III）和寡肽（包括SAP）。在碱性或高Ca^<++>海水中，阿里斯诱导顶体反应.在正常海水中，阿里斯和Co-阿里斯的组合诱导顶体反应，而不增加PH_i。N-乙酰氨基己糖苷酶是罗雷氏盐蛙（Halocynthia roretzi）精子中最强的糖苷酶，其活性和结构尚不清楚。第二个有效的是-L-岩藻糖苷酶，似乎作为卵黄涂层结合蛋白。卵黄被膜上的精子受体末端含有L-Fuc、D-GalNAc和D-GlcNAc。事实上，卵黄外壳的主要N-糖苷链具有这样的结构。在1-甲基腺嘌呤诱导的Asterina卵母细胞成熟过程中，一个39 KGi蛋白和一个高底物特异性的胰蛋白酶型蛋白酶分别参与MPF形成的前、后步骤。