OOCYTE CORTICAL MATURATION AND GRANULE ACTIVATION

卵母细胞皮质成熟和颗粒激活

• 批准号: 2673566
• 负责人: THOMAS W DUCIBELLA
• 金额: $ 20.48万
• 依托单位: TUFTS UNIVERSITY BOSTON
• 依托单位国家: 美国
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-07-01 至 2000-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2673566
• 关键词: aneuploidy; calcium flux; carbohydrate receptor; cell cell interaction; egg /ovum; egg proteins; exocytosis; female; fertilization; granule; inositol phosphates; laboratory mouse; sperm; tissue /cell culture

In humans and other mammals, 1-5% of fertilized eggs become triploid, abort, and die. Human triploidy is primarily due to fertilization by more than one sperm and is usually prevented by the release of egg cortical granules (CGs) whose contents biochemically modify the egg's zona pellucida. In a mouse model, the long-term objectives are to identify: (Aim 1) an important cause of triploidy that originates from a failure of CG release and (Aim 2) egg proteins responsible for the prevention of triploidy. The failure of CG release, associated with incomplete cytoplasmic maturation in mice and humans, involves second messengers and their targets: inositol trisphosphate (IP3), calcium (Ca), and Ca-dependent proteins. Aims: 1) Development of Ca signaling for CG release: Does the ability to undergo CG exocytosis develop from increases in Ca release (hypothesis A) or an increased response to Ca (hypothesis B)? Prior to ovulation, is CG exocytosis failure due to insufficient elevation of Ca, a lack of sensitivity to Ca, and/or improper amount, localization, or phosphorylation of IP3 receptor isoforms (channels for intracellular Ca release)? 2) Biochemical characterization of individual (egg CG) proteins released at fertilization. Testing the hypothesis that one or more proteins are responsible for the zona protein (ZP3)-mediated block to polyspermy, characterized by reductions in sperm binding and in the acrosome reaction. Technical Methods: High resolution fluorescence microscopy and computerized image analysis of CGs, Ca imaging, electrophoresis, ultrasensitive chemiluminescence protein detection, and bioassays. Significance: Aim 1) Identification of a signaling deficiency would provide an important 'marker' for oocyte cytoplasmic maturation and a more detailed scientific explanation for the origin of abnormal triploid abortuses. Determination of a quantitative relationship between egg Ca and CG release (& cell cycle resumption) will advance our knowledge of the role of Ca in fertilization. Aim 2) The biochemical identification of the egg protein(s) modifying ZP3 is an important step in elucidating the molecular mechanism responsible for the mammalian block to polyspermy. This research may lead to a new non-invasive egg activation assay of released CG proteins (for optimizing or monitoring animal and human in vitro fertilization).

在人类和其他哺乳动物中，1-5％的受精卵变成 三倍体， 流产，死了。 人类三倍主要是由于受精 经过 超过一个精子，通常可以通过释放鸡蛋来阻止 皮质颗粒（CGS）的含量在生化上修改了 鸡蛋 Zona Pellucida。 在鼠标模型中，长期目标是 识别：（目标1）造成三倍的重要原因 来自 CG释放和（AIM 2）卵子蛋白的失败负责 预防三倍体。 CG释放的失败，相关 和 小鼠和人类中不完全的细胞质成熟涉及 第二 信使及其目标：肌醇三磷酸盐（IP3），钙 （CA）， 和CA依赖性蛋白。 目标： 1）开发CG释放的CA信号传导：是否能够 CA释放的增加而出现CG胞吐作用 （假设A） 还是对CA的反应增加（假设B）？ 排卵之前 是CG 由于CA的升高不足而导致的胞吞作用失败，缺乏 对CA的敏感性和/或数量不当，本地化或 IP3受体同工型的磷酸化（通道 细胞内Ca 发布）？ 2）个体（EGG CG）蛋白的生化表征 发行 受精。 测试一种或多种蛋白质的假设 是 负责Zona蛋白（ZP3）介导的块 多人物， 其特征是精子结合和高级体中的降低。 反应。 技术方法：高分辨率荧光显微镜和 CGS，CA成像，电泳的计算机图像分析， 超敏化化学发光蛋白检测和生物测定。 意义：目标1）识别信号缺乏将 为卵母细胞胞质成熟提供重要的“标记”和 一个 对异常起源的更详细的科学解释 三倍体 堕胎。 确定定量关系 鸡蛋 和CG释放（和细胞周期恢复）将提高我们的知识 的 CA在受精中的作用。 目标2）生化 鉴别 修饰ZP3的卵子蛋白是重要的一步 阐明 负责哺乳动物块的分子机制 多工。 这项研究可能导致新的非侵入卵 激活 释放CG蛋白的测定（用于优化或监测动物 和 人体体外受精）。