REGULATION OF SPERM FUNCTION BY PROTEIN PHOSPHORYLATION

描述：(改编自申请人的摘要)这是第一次 修订后的应用程序旨在评估精子的生化调节 能动性。长期目标是定义潜在的生化机制 运动性的发展和调节，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之间的平衡。 磷酸酶。申请者已经确定了一种精子特异性蛋白质 参与调节精子运动的磷酸酶，PP1g2。高 这种酶的活性导致精子活动率低，而精子活力强 活动精子表现出较低的酶活性。PP1g2的特异性抑制导致 静止精子运动的启动及对运动速度和运动速度的刺激 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，即PP1g2是一个关键组件 调节精子的磷酸化，从而调节精子的活力。 这一建议的重点是研究生物化学机制。 调节PP1g2。研究人员假设，两个精子特异的 调节蛋白P33和P72控制活性和亚细胞 PP1g2基因的定位。此外，他认为PP1g2的相互作用 与P33的结合受糖原合成酶-3的磷酸化调节。三 检验这些想法的具体目标制定如下：(1)提纯和 对抑制物P33进行测序，并确定其如何调节PP1g2。(2)至 确定PP1g2亚细胞靶向性的分子基础 精子鞭毛和精子头的前部。(3)决定如何 PP1g2及其激活酶糖原合成酶激酶-3受 精子在细胞内的第二信使。 对这种新的精子生化机制的阐明应该会导致更好的 对雄配子功能的理解，导致了新的方法 调节精子的活力，可以更好地诊断和治疗 男性因素不育症。

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.