The Bivalve Egg's Lectin Recognizing Sperm Glycosphingolipid

从淡水双壳类水母（Hyriopsis schlegelii）精子中分离得到一种酸性鞘糖脂，其结构为：GlcA4Me 1-4[GalNAc3Me 1-3] Guc 1-4GlcNAc 1-2Man 1-3[Xy1 -2]Man 1-4Glc 1-1Ceramide。这是一种独特的糖脂，因为它含有4- o - mathylglucur醛酸和一个位于内部的焦点，作为糖残基，也被认为专门存在于双壳精子的细胞表面，分类学上属于Veneridae， Unionidae和mytilidae。这些内在的事实让我们探索精子-卵子相互作用的可能作用。然后，通过与携带脂质的辛基- sepharose的亲和库仑层析，我们试图从100,000 x g的海蚌蛋均质上清中提取某些识别酸性脂质的物质。该提取物被证明可以凝集某些双壳类动物的精子，以及酸性含脂脂质体。在sd聚丙烯酰胺凝胶电泳上，大部分提取物被确认在表观分子质量100K、80k、60K、40K和20KDa五个区域内的条带上。所有这些都被发现直接与^ 3h标记的酸性脂质结合，这表明在20KDa的生产中发现了初始结合活性。将活贻贝卵与用提取物预先孵育的精子混合，发现它完全抑制了受精。

An acidic glycosphingolipid was isolated from spermatozoa of the fresh-water bivalve, Hyriopsis schlegelii, and it was found to have the following structure: GlcA4Me 1-4[GalNAc3Me 1-3] Guc 1-4GlcNAc 1-2Man 1-3[Xy1 1-2]Man 1-4Glc 1-1Ceramide. This is a unique glycolipid, in that a 4-O-mathylglucuronic acid and an internally located fucose are contained as sugar residues and also thought to exist specifically on the cell surface of the bivalve spermatozoa placed taxonomically in the Veneridae, Unionidae and mytilidae. These intrinsic facts let us explore possible roles for sperm-egg interaction. Then, by affinity coulumn chromatography with the octyl-Sepharose carrying lipid, we tried to extract certain substances that recognize the acidic lipid from a 100,000 x g supernatant of the Hyriopsis egg homogenates. The extract was demonstrated to agglutinate spermatozoa from certain bivalve species, and also the acidic lipid-containing liposomes. On SDSpolyacrylamide gel electrophoresis, the majority of the extract was confirmed to the bands within the five regions of apparent molecular mass: 100K, 80, 60K, 40K, and 20KDa. All of them were found to directly bind to ^3H-labelled acidic lipid, and this indicated that the initial binding activity was found in a production of the 20KDa. When living Mytilus edulis eggs were mixed with sperm preincubated with the extract, it was found to completely inhibit the fertilization.