EPIDIDYMAL MATURATION OF MAMMALIAN SPERM

哺乳动物精子的附睾成熟

• 批准号: 5212410
• 负责人: GEROGE L GERTON
• 金额: --
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/5212410
• 关键词: acrosin; acrosome; bioassay; biological signal transduction; carbohydrate sequence; carbohydrate structure; egg /ovum; enzyme activity; enzyme structure; epididymis; glycoprotein structure; glycosylation; guinea pigs; high performance liquid chromatography; immunoaffinity chromatography; ion exchange chromatography; oligosaccharides; posttranslational modifications; protein purification; protein sequence; proteolysis; sperm capacitation; testis; tissue /cell culture; zymogens

The broad, long term objective of this research proposal is to understand the process of epididymal maturation of sperm. this poorly defined process is essential for fertilization; sperm that have entered the cauda epididymis and vas deferens are able, after a period of capacitation, to fertilize eggs whereas sperm taken from the testis or caput epididymis are not. The working model is that sperm maturation within the epididymis is not a single event but involves sequential, progressive in sperm properties brought about by the transduction of signals from the epididymal secretions to the intracellular spaces of the sperm. The challenge in understanding sperm maturation in the epididymis, therefore, is one of determining the modifications to sperm components that are essential for fertilization, characterizing how these components become functional as a result of epididymis-induced alterations, and elucidating the epididymal factors or conditions that stimulate these changes. This proposed research will examine changes that take place within the confines of the important sperm acrosome, the acrosome. The alterations to be investigated are the structural and functional modifications of the sperm-specific serine protease zymogen, proacrosin, and structural changes to another acrosomal glycoprotein, acrogranin. specific Aim 1 will characterize, using high performance liquid chromatography for carbohydrate analysis, the modification of proacrosin oligosaccharides that takes place in the corpus epididymis. Specific Aim 2 will determine how these alterations affect enzymatic activity. Specific Aim 3 will determine where specific cleavages in the polypeptide backbone of acrogranin occur by partial amino acid sequencing of products isolated from cauda epididymal sperm. Specific Aim 4 will use the biochemical information from Specific Aims 1 and 3 to predict and to identify the specific glycosidase(s) and protease(s) responsible for the epididymis-induced alterations of proacrosin and acrogranin. Specific Aim 5 is to develop a bioassay using the modifications of proacrosin and acrogranin as markers of epididymal maturation. this bioassay will be used to determine the conditions or substances that initiate these changes in testicular and caput epididymal sperm. These experiments will provide a unique approach to investigate epididymal maturation of sperm. The bioassay developed during the proposed project will be used in future studies to characterize the conditions or purify the factors responsible for initiating this aspect of sperm maturation. Furthermore, the information gained from these studies will find application in the treatment of male infertility caused by blockage of the epididymis or vas deferens. New approaches toward development of a male contraceptive may also result from the information gained from these studies.

这项研究提案的广泛、长期目标是理解 精子附睾成熟的过程。这个定义不明确的过程 对受精是必不可少的；进入尾部的精子 附精和输精管在获能一段时间后，能够 使卵子受精，而从睾丸或附睾头取出的精子 不。其工作模式是精子在附睾体内成熟 不是单个事件，而是涉及精子特性的连续、渐进 由附睾腺分泌物的信号转导引起的 到精子的细胞内空间。理解中的挑战 因此，精子在附睾中的成熟是决定精子成熟度的因素之一。 对受精过程中必不可少的精子成分进行修饰， 描述这些组件是如何通过 附睾症引起的改变，并阐明附睾性因子或 刺激这些变化的条件。这项拟议的研究将 检查在重要精子的范围内发生的变化 顶体，顶体。要调查的改动是 精子特异性丝氨酸的结构和功能修饰 另一个顶体的蛋白酶原、顶体酶原和结构变化 糖蛋白，顶体颗粒素。特定目标1将描述，使用高 用于碳水化合物分析的高效液相色谱 原顶体蛋白低聚糖在语料库中的修饰 附睾症。具体目标2将确定这些变化如何影响 酶活性。特定目标3将确定特定卵裂的位置 在顶体蛋白的多肽骨架中以部分氨基酸形式存在 附睾尾精子分离产物的测序。特定目标 4将使用来自特定目标1和3的生化信息来 特异性糖苷酶(S)和蛋白酶(S)的预测和鉴定 对附睾症引起的顶体原和顶体蛋白的改变负责 肢端颗粒素。具体目标5是开发一种使用 精子顶体原和顶体颗粒素作为附睾标志物的修饰 成熟。这种生物测定将被用来确定条件或 在睾丸和附睾头引起这些变化的物质 精子。这些实验将提供一种独特的方法来研究 精子的附睾性成熟。生物测定是在拟议的 项目将在未来的研究中用于表征条件或 提纯启动精子这一方面的因素 成熟。此外，从这些研究中获得的信息将 在治疗阻滞性男性不育中的应用 附精或输精管。开发一种新的方法 男性避孕药也可能是从这些信息中获得的 学习。