Mechanisms of intracellelar signal transduction in sperm-induced mause egg activation

精子诱导小鼠卵子激活的细胞内信号转导机制

• 批准号: 08671931
• 负责人: AYABE Takuya
• 金额: $ 1.41万
• 依托单位: Teikyo University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08671931/
• 关键词: egg activation; intracellular Ca^<2+> store; IP_3; IP_3 receptor; ryanodine; ryanodine receptor; cyclic ADP ribose; 第2極体放出; 前核形成; ヒストンH1蛋白; 3量体GTP結合蛋白(G蛋白); beta; gammaサブユニット

Sperm-induced activation of mammalian eggs is associated with a transient increase in Ca^<2+> concentrations thought to be derived from inositol 1,4,5-trisphosphate-sensitive and -insensitive intracellular stores. whereas the importance of inositol 1,4,5-trisphosphate-sensitive Ca^<2+> stores has been evaluated, the identity and role of inositol 1,4,5-trisphosphate-insensitive stores are poorly understood. To explore the role of the ryanodine-sensitive Ca^<2+> store, I first used reverse transcription-polymerase chain reaction to identify transcripts of the ryanodine receptor in eggs and determined that transcripts for the type 2 and 3 receptor were present. Immunoprecipitation of radioiodinated egg extracts with an antibody that recognizes both type 2 and 3 receptors detected specifically a band of M_r=520,000. Immunolocalization of the receptor (s) using laser-scanning confocal microscopy revealed that the receptor (s) was uniformly distributed in the cortex of the germinal vesicle-i … More ntact oocyte, but became asymmetrically localized to the cortex in a region apposed to the meiotic spindle in the metaphase II-arrested egg ; this asymmetrical localization developed by metaphase I.The role of the ryanodine receptor in mouse egg activation was examined by determining the effects of microinjected ryanodine or cyclic ADP ribose on endpoints of egg activation in either uninseminated or inseminated eggs. Ryanodine induced the conversion of the zona pellucida glycoprotein ZP2 to its post-fertilization form ZP2_f in a biphasic concentration-dependent manner ; nanomolar concentrations stimulated this conversion, whereas micromolar concentrations had no stimulatory effect. Cyclic ADP ribose also promoted the ZP2 conversion, but with a hyperbolic concentration dependence. Neither of these compounds induced cell cycle resumption. Last, treatment of eggs under conditions that would block the release of Ca^<2+> from the ryanodine-sensitive store had no effect on any event of egg activation following fertilization. Results of these experiments suggest that although ryanodine receptors are present and functional, release of Ca^<2+> from this store is not essential for sperminduced mouse egg activation. Less

精子诱导的哺乳动物卵子激活与Ca^<2+>浓度的短暂增加有关，这被认为是来源于肌醇1,4,5-三磷酸敏感和-不敏感的细胞内储存。虽然已经评估了肌醇1,4,5-三磷酸敏感Ca^<2+>储存的重要性，但对肌醇1,4,5-三磷酸不敏感储存的身份和作用知之甚少。为了探究ryanodine敏感的Ca^<2+>储存的作用，我首先使用逆转录-聚合酶链反应鉴定了鸡蛋中ryanodine受体的转录本，并确定了2型和3型受体的转录本存在。用一种同时识别2型和3型受体的抗体对放射性碘化鸡蛋提取物进行免疫沉淀，特异性检测到M_r=52万的条带。利用激光共聚焦显微镜对受体进行免疫定位，发现受体均匀分布在生发囊泡的皮层中，与卵母细胞接触较多，但在中期阻滞的卵中，受体不对称地定位于与减数分裂纺锤体相对的皮层区域；ryanodine受体在小鼠卵子激活中的作用通过测定微注射ryanodine或环ADP核糖对未受精卵或受精卵激活终点的影响来研究。赖诺定诱导透明带糖蛋白ZP2向受精后形态ZP2_f的转化呈双相浓度依赖性；纳摩尔浓度刺激这种转化，而微摩尔浓度没有刺激作用。环状ADP核糖也促进ZP2转化，但具有双曲线浓度依赖性。这两种化合物都不能诱导细胞周期恢复。最后，在阻止Ca^<2+>从ryanoine敏感库释放的条件下处理卵子，对受精后卵子激活的任何事件都没有影响。这些实验结果表明，尽管ryanodine受体存在并且具有功能，但Ca^<2+>的释放对于精子诱导的小鼠卵子激活不是必需的。少

项目成果

綾部 琢哉、森 宏之: "Ryanodine受容体のマウス卵受精時細胞内カルシウム上昇機構における意義" 第14回日本受精着床学会講演抄録集. 93-93 (1996)

Takuy​​a Ayabe、Hiroyuki Mori：“Ryanodine 受体在小鼠卵子受精过程中细胞内钙升高机制中的意义”第 14 届日本受精与着床学会会议记录 93-93 (1996)。

Moore, G.D., Ayabe, T., Kopf, G.S.and Schultz, R.M.: "Temporal patterns of gene expression of G1-S cyclins and cdks during the first and second mitotic cell cycles in mouse embryos." Mol.Reprod.Dev.45. 264-275 (1996)

Moore, G.D.、Ayabe, T.、Kopf, G.S. 和 Schultz, R.M.：“小鼠胚胎第一和第二有丝分裂细胞周期中 G1-S 细胞周期蛋白和 cdks 基因表达的时间模式。”

綾部 琢哉、森 宏之: "マウス卵成熟過程におけるryanodine感受性Caプールの変化" 日本不妊学会雑誌. 41・4. 158-158 (1996)

Takuy​​a Ayabe、Hiroyuki Mori：“小鼠卵母细胞成熟过程中兰尼碱敏感性钙池的变化”，日本不孕协会杂志 41・4（1996 年）。

Ayabe, T., Tsutsumi, O., Sakai, H., Yoshikawa, H.Yano, T., Kurimoto, F.and Taketani, Y.: "Increased circulating levels of insulin-like growth factor-I and decreased circulating levels of insulin-like growth factor binding protein-l in postmenopausal women

Ayabe, T.、Ttsutsumi, O.、Sakai, H.、Yoshikawa, H.Yano, T.、Kurimoto, F. 和 Taketani, Y.：“胰岛素样生长因子-I 的循环水平增加，循环水平降低

Ayabe, T.et al.: "Increased circulating levels of insulin-like growth factor-I and decreased circulating levels of insulin-like growth factor binding protein-1 in postmenopausal women with endometrial cancer." Endocrine Journal. 44. 419-424 (1997)

Ayabe, T.等人：“患有子宫内膜癌的绝经后妇女中胰岛素样生长因子-I 的循环水平增加，胰岛素样生长因子结合蛋白-1 的循环水平降低。”