Molecular mechanisms underlying self-sterility in the ascidians

海鞘自体不育的分子机制

• 批准号: 06454685
• 负责人: HOSHI Motonori
• 金额: $ 3.84万
• 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: 1994
• 资助国家: 日本
• 起止时间: 1994 至 1995
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06454685/
• 关键词: allo-recognition; sperm-egg-binding; contact-reaction; hemocyte; glycoprotein; Ascidian; alpha-L-Fucosidase; Metalloendoprotease; アロ認識; 精子結合; キメラ胚; フェノールオキシダーゼ

Little is so far known on the molecular mechanisms underlying self-sterility in the ascidian gametes, a typical example of the allogeneic recognition. However, an allogeneic interaction named "contact reaction" is well established in the hemocytes of the ascidian, Halocynthia roretzi. On an assumption that allo-recognition molecules in gametes and those in hemocytes are the same or closely related, we searched for such molecules in the gametes and hemocytes of the ascidian. Major findings in this project are itemized as follows.1) Vacuolate cells secreted phenol oxidase upon contact reaction, which allowed us to develop a quantitative assay for the contact reaction.2) Vacuolated cells expressed an allo-molecule (s) and its receptor, whereas granular cells did not express such a molecule in a way to be recognized by vacuolated cells.3) Follicle cells attaching to the vitelline coat expressed an allo-molecule (s).4) cDNA of sperm alpha-L-fucosidase that mediates sperm binding to the vitelline coat was cloned and partially sequenced.5) A putative sperm-receptor glycoprotein of 70 kDa was isolated from the vitelline coat and partially sequenced.6) The gametes became self-fertile in high Mg^<2+>-or caffeine-seawater.

到目前为止，在海外配子中的自我锻造性的分子机制上尚未知道，这是同种异体识别的典型例子。然而，在海囊鸟内thia roretzi的血细胞中，一种称为“接触反应”的同种异体相互作用已得到很好的确定。假设在配子中和血细胞中的异族识别分子是相同或密切相关的，我们在海藻的配子和血细胞中搜索了这种分子。该项目中的主要发现如下。1）在接触反应时将分泌的酚氧化酶排出，这使我们能够为接触反应开发定量测定法。2）真空细胞表达了一种吸液（S）的受体及其受体及其受体，而粒状细胞未通过疫苗的细胞来识别粒细胞的表达，以表达这种分子。33）效率3）33）效率3）。克隆并进行了测序的精子的精子α-L-核酶（S）.4）cDNA，该cDNA介导了与卵脂涂层结合的精子结合并进行了测序。5）一种假定的精子受体糖蛋白，为70 kDa分离出70 kDa的蛋白质，并从植物学上分离出来。咖啡因 - 盐水。

项目成果

A. Ushiyama, A. Shima and M. Hoshi: "Estimation by radiation inactivation of the minimum functional size of acrosome reaction-inducing substance (ARIS) in the starfish, Asterias amurensis" Zygote. 3(in press). (1995)

A. Ushiyama、A. Shima 和 M. Hoshi：“通过辐射灭活估计海星 Asterias amurensis 中顶体反应诱导物质 (ARIS) 的最小功能大小”合子。

M. Hoshi: "Glycosidases, Proteases and Ascidian Fertilization" Seminars Dev. Biol.5. 201-208 (1994)

M. Hoshi：“糖苷酶、蛋白酶和海鞘施肥”研讨会开发。

K. Chiba: "A Periodic Network of G Protein βγ Subunit Coexisting with Cytokeratin Filament in Starfish Oocytes" Dev. Biol. in press.

K. Chiba：“海星卵母细胞中与细胞角蛋白丝共存的 G 蛋白 βγ 亚基的周期性网络”Dev Biol。

M.Hoshi: Allogeneic recognition in ascidian fertilization. In Sixth Lake Shirakaba Placenta Conference 1994 Biology of Pregnancy ed.T.Nakayama and T.Makino, Keiseisha, Tokyo, 60-65 (1995)

M.Hoshi：海鞘受精中的同种异体识别。

F. J. Longo, M. Woerner, K. Chiba and M. Hoshi: "Cortical changes in starfish (Asterina pectinifera) oocytes during 1-methyladenine-induced maturation and fertilization/activation" Zygote. 3. 225-239 (1995)

F. J. Longo、M. Woerner、K. Chiba 和 M. Hoshi：“1-甲基腺嘌呤诱导的成熟和受精/激活过程中海星（Asterina pectinifera）卵母细胞的皮质变化”合子。