REGULATION OF SPERM FUNCTION BY PROTEIN PHOSPHORYLATION

蛋白质磷酸化对精子功能的调节

• 批准号: 6637061
• 负责人: SRINIVASAN VIJAYARAGHAVAN
• 金额: $ 19.99万
• 依托单位: KENT STATE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-06-01 至 2004-12-06
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6637061
• 关键词: acidity /alkalinity; calcium ion; cilium /flagellum motility; cyclic AMP; enzyme activity; flagellum; immunoprecipitation; isozymes; phosphoprotein phosphatase; phosphoproteins; phosphorylation; protein kinase; recombinant proteins; sperm; sperm motility

DESCRIPTION: (Adapted from the applicant's abstract) This is a first time revised application intended to assess biochemical regulation of sperm motility. The long-term goal is to define the biochemical mechanisms underlying development and regulation of motility with emphasis on considerations of phosphorylation of proteins associated with the axoneme. Levels of phosphorylation are a balance between the action of protein kinases and protein phosphatases. The applicant has identified a sperm-specific protein phosphatase, PP1g2 that is involved in regulation of sperm motility. High activity of this enzyme results in low sperm motility, whereas vigorously motile sperm exhibit low enzyme activity. Specific inhibition of PP1g2 leads to initiation of motility in immotile sperm and to the stimulation of velocity and flagellar beat amplitude in motile sperm. Genetic and biochemical studies support the hypothesis of the applicant that PP1g2 is a key component regulating sperm phosphorylation and, hence, motility. The focus of this particular proposal is to study the biochemical mechanisms regulating PP1g2. The investigator hypothesizes that two sperm-specific regulatory proteins, P33 and P72, control the activity and the sub cellular localization of PP1g2. Furthermore, he believes that the interaction of PP1g2 with P33 is regulated by glycogen synthase kinase-3 phosphorylation. Three Specific Aims to test these ideas are formulated as follows: (1) To purify and sequence the inhibitor P33 and to determine how it regulates PP1g2. (2) To determine the molecular basis for the sub cellular targeting of PP1g2 to the sperm flagellum and the anterior region of the sperm head. (3) To determine how PP1g2 and its activating enzyme glycogen synthase kinase-3 are regulated by sperm intracellular second messengers. Elucidation of such novel sperm biochemical mechanisms should lead to a better understanding of male gamete function, result in novel approaches for the regulation of sperm motility, and could enable better diagnosis and treatment of male factor infertility.

描述：（改编自申请人的摘要）这是第一次 修订后的申请旨在评估精子的生化调节 动力。长期目标是确定潜在的生化机制 运动的发展和调节，重点考虑 与轴丝相关的蛋白质的磷酸化。级别 磷酸化是蛋白激酶和蛋白质作用之间的平衡 磷酸酶。申请人已鉴定出精子特异性蛋白质 磷酸酶，PP1g2，参与精子活力的调节。高的 这种酶的活性导致精子活力低下，而精子活力旺盛 活动精子表现出低酶活性。 PP1g2 的特异性抑制导致 不动精子的运动启动以及速度和速度的刺激 活动精子的鞭毛搏动幅度。遗传和生化研究 支持申请人的假设，PP1g2是一个关键组件 调节精子磷酸化，从而调节精子活力。 这个特别提案的重点是研究生化机制 调节PP1g2。研究人员假设两个精子特异性 调节蛋白 P33 和 P72 控制活性和亚细胞 PP1g2 的本地化。此外，他认为PP1g2的相互作用 P33 受糖原合酶激酶 3 磷酸化调节。三 检验这些想法的具体目标制定如下： (1) 纯化和 对抑制剂 P33 进行测序并确定其如何调节 PP1g2。 (2) 至 确定 PP1g2 亚细胞靶向的分子基础 精子鞭毛和精子头的前部区域。 (3) 确定如何 PP1g2 及其激活酶糖原合成酶激酶 3 受调节 精子细胞内第二信使。 阐明这种新颖的精子生化机制应该会带来更好的结果。 对雄配子功能的了解，产生了新的方法 调节精子活力，可以实现更好的诊断和治疗 男性因素不育症。