SULFATED GLYCOLIPID THAT REGULATES DEVELOPMENT OF MALE GERM CELLS

调节雄性生殖细胞发育的硫酸糖脂

基本信息

批准号：
13670138
负责人：
HONKE Koichi
金额：
$ 2.3万
依托单位：
OSAKA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2002
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13670138/
关键词：
SPERMATOGENESIS MEIOSIS SULFATED GLYCOLIPID SEMINOLIPID SULFOTRANSFERASE KNOCKOUT MOUSE

项目摘要

The sulfated glycolipid, seminolipid occupies more than 90% of total glycolipids in the testis and is specifically expressed in the testis. Seminolipid is biosynthesized in the Golgi membranes of spermatocytes during spermatogenesis. First, a galactosyltransferase called ceramide galactosyltransferase (CGT) acts on the precursor glycerolipid, and synthesizes an intermediate product, galactosylalkylacylglycerol (GaIEAG). Then, a sulfotransferase called cerebroside sulfotransferase (CST) catalyzes the sulfation of GaIEAG, synthesizing the terminal product, seminolipid. We have found that the testes of CST-deficient mice completely lack seminolipid and spermatogenesis is arrested at the metaphase of the first meiosis. These findings indicate that seminolipid is essential for spermatogenesis (Proc.Natl.Acad.Sci.USA 99, 4227-4232, 2002). Next, we have been studying how seminolipid is involved in spermatogenesis. First, we examined the issue whether seminolipid exists in the lipid raft on the plasma membranes of spermatocytes. To this end, we had established the procedure to isolate spermatocytes from mouse testis using a density-gradient centrifugation. As a result, we confirmed that seminolipid is included in the lipid raft. Similarly, we found that another sulfated glycolipid, sulfatide is also included in the lipid raft of brain myelin sheath. Secondly, we have developed a photo-sensitive carbohydrate probe to identify the molecules that interact with seminolipid on the cell-suface of spermatocytes. We are planning to introduce this probe into cultured spermatocytes and detect such molecules in living cells. Thirdly, we have been trying to inject seminolipid into the seminiferous tubules and make the testis to resume spermatogenesis

硫酸糖胶质固醇占睾丸中总糖脂的90％以上，并在睾丸中特别表达。精子发生过程中精子细胞的高尔基膜中塞米诺脂质是生物合成的。首先，一种称为神经酰胺半乳糖基转移酶（CGT）的半乳糖基转移酶作用于前体甘油脂肪，并合成中间产物半乳乙酰烷基酰基甘油（GAIEAG）。然后，一种称为脑二硫代硫代转移酶（CST）的硫代转移酶催化了盖伊格的硫酸化，合成了末端产物塞米诺脂脂。我们发现，CST缺陷型小鼠的睾丸完全缺乏塞诺脂脂，并且在第一个减数分裂的中期被捕。这些发现表明，塞诺脂脂对于精子发生至关重要（proc.natl.acad.sci.usa 99，4227-4232，2002）。接下来，我们一直在研究Seminolipid如何参与精子发生。首先，我们检查了精子细胞质膜上的脂质筏中是否存在Seminolipid。为此，我们已经建立了使用密度梯度离心分离小鼠睾丸的精子细胞的程序。结果，我们确认脂质筏中包括塞米脂脂。同样，我们发现另一种硫化的糖脂，硫化物也包括在脑髓鞘鞘的脂质筏中。其次，我们开发了一种光敏的碳水化合物探针，以鉴定与精子细胞细胞表面上与塞诺脂相互作用的分子。我们计划将此探针引入培养的精子细胞中，并在活细胞中检测到这种分子。第三，我们一直在试图将半脂质注入精子小管中，并使睾丸恢复精子发生