Molecular Mechanisms underlying Allo-recoguition in Ascidians

海鞘同种异体识别的分子机制

• 批准号: 04454024
• 负责人: HOSHI Motonori
• 金额: $ 3.71万
• 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 (B)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04454024/
• 关键词: Allo-recognition; Ascidians; Self-sterility; Contant Reaction; Hemocyte; Sperm Binding; Chimeric Embryos; Pheno Oxidase; 組織適合抗原; 受精

The contact reaction of hemocytes and self-sterility of gametes are typical examples of all-recognition in the ascidians We have found in Halocymhia roreizi that the contact reaction is accompanied with a burst of oxygen consumption by phenol oxidase. Basing upon this finding, we developed a method to quantify the contact reaction Similar bursts were observed when hemocytes were mixed eggs or follicle cells from different individuals.Sperm binding to the vitelline coat is a step of allo- recognition in Ciona imtesinalis. Although H.roreizi is strictly self-stcrile, autologous as well as homologous spem bound to the vitelline coat. However, autologous sperm did not block fertilozation by homologous sperm at all, suggesting that binding of autologous sperm is phusiologically meaningless for fertilization. A highly hydrophobic glycoprotein of 70 kDa isolated from H.roretzi vitcllinc coats was purificd as a sperm-receptor. Thc N-terminal eicosapeptide and four other fragments (sixty residues in total)of this protein were sequenced.In order to answer a question whether self-sterility is purely genetic or it depends to some extent on a kind of clonal selection during devclopment, 8-ccll embryos of C.intestinalis were dissected into left and right halves to make chimeric chimeric embryos. No sexually matured chimeras were so for obtained.

血细胞的接触反应和配子的自不育是海鞘类全识别的典型例子。我们在Halocymhia roreizi中发现，接触反应伴随着酚氧化酶的突然耗氧。基于这一发现，我们开发了一种量化接触反应的方法。当血细胞与来自不同个体的卵或卵泡细胞混合时，观察到类似的爆发。精子与卵黄层的结合是玻璃海鞘同种异体识别的一个步骤。尽管H.roreizi 是严格自不育的，但自体和同源精子均与卵黄皮结合。然而，自体精子根本不会阻止同源精子的受精，这表明自体精子的结合对于受精在生理学上没有意义。从 H.roretzi vitcllinc 外壳中分离出 70 kDa 的高度疏水性糖蛋白，将其纯化为精子受体。对该蛋白的N端二十肽和其他四个片段(总共60个残基)进行了测序。 为了回答自体不育是纯粹遗传的还是在一定程度上取决于发育过程中的克隆选择的问题，将C.intestinalis的8-ccll胚胎解剖成左右两半，制备嵌合嵌合胚胎。没有获得性成熟的嵌合体。

项目成果

A.Ushiyama: "Specific Binding of Acrosome Reaction-Inducing Substance to the Head of Starfish Spermatozoa" Zygote. 1. 121-127 (1993)

A.Ushiyama：“顶体反应诱导物质与海星精子头部的特异性结合”合子。

S.Takizawa: "Effects of Protease Inhibitors on Binding of Sperm to the Vitelline Coat of the Ascidian Eggs:Implications for Participation of Proteasome(Multicatalytic Proteinase Complex)" J.Exp.Zool.267. 86-91 (1993)

S.Takizawa：“蛋白酶抑制剂对精子与海鞘卵卵黄膜结合的影响：蛋白酶体（多催化蛋白酶复合物）参与的影响”J.Exp.Zool.267。

星 元紀(分担): "細胞社会のグリオバイオロジー" 講談社サイエンチフィク, 238 (1993)

Motonori Hoshi（撰稿人）：“细胞社会的胶质生物学”讲谈社科学，238（1993）

M.Hoshi: "Glycosphingolipids:Important Membrane Components Rather Neglected in Biotechnology" Biol.Internat.special issue, 112 (1993)

M.Hoshi：“鞘糖脂：在生物技术中相当被忽视的重要膜成分”Biol.Internat.特刊，112 (1993)

Motonori Hoshi: "Metalloendoproteases Are Involved in Gamete Fusion of Ciona intestinalis" Develop.Biol.153. 165-171 (1992)

Motonori Hoshi：“金属内蛋白酶参与海鞘配子融合”Develop.Biol.153。