REGULATION OF SPERM FUNCTION BY PROTEIN PHOSPHORYLATION

蛋白质磷酸化对精子功能的调节

• 批准号: 6266883
• 负责人: SRINIVASAN VIJAYARAGHAVAN
• 金额: $ 20.31万
• 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 2004-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6266883
• 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：（根据申请人的摘要进行了改编）这是第一次 旨在评估精子生化调节的修订应用 运动。长期目标是定义基础的生化机制 发展和调节运动，重点是考虑 与轴突相关的蛋白质的磷酸化。水平 磷酸化是蛋白激酶和蛋白质的作用之间的平衡 磷酸酶。申请人已经确定了精子特异性蛋白 磷酸酶，PP1G2，参与精子运动的调节。高的 该酶的活性导致精子运动性较低，而剧烈 运动精子表现出低酶活性。 PP1G2的特定抑制导致 启动免疫力精子和速度的刺激和 鞭毛在运动精子中击败振幅。遗传学和生化研究 支持申请人的假设，即PP1G2是关键组成部分 调节精子磷酸化，从而调节运动性。 该特定建议的重点是研究生化机制 调节PP1G2。研究者假设两个精子特定于 调节蛋白p33和p72控制活性和亚细胞 PP1G2的定位。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 测试这些想法的具体目的如下：（1）净化和 序列抑制剂p33并确定它如何调节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区域。 （3）确定如何 P1G2及其活化酶糖原合酶激酶-3受到调节 精子细胞内第二使者。 阐明这种新型精子生化机制应导致更好 了解男配子功能，导致新颖的方法 精子运动的调节，可以更好地诊断和治疗 男性因素不育。