Regulation of sperm motility by the Rho signaling pathway

Rho 信号通路对精子活力的调节

• 批准号: 8339875
• 负责人: DANIEL W CARR
• 金额: $ 6.3万
• 依托单位: OREGON HEALTH & SCIENCE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-28 至 2014-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8339875
• 关键词: A kinase anchoring protein; Accounting; Adaptor Signaling Protein; Affect; Binding; Biochemical; Cilia; Couples; Cyclic AMP; Cyclic AMP-Dependent Protein Kinases; Diagnosis; Dimerization; Disease; Docking; Drug Design; Enzymes; Event; Fertility; Flagella; Genomics; Goals; Human; In Vitro; Infertility; Knockout Mice; Knowledge; Literature; Male Infertility; Measures; Microtubules; Molecular; Mus; Muscle Contraction; Mutant Strains Mice; Names; Pathway interactions; Peptides; Phosphorylation; Physiological; Plant Roots; Process; Protein Binding; Protein Isoforms; Protein phosphatase; Proteins; Publishing; Regulation; Role; Scaffolding Protein; Signal Pathway; Signal Transduction; Slide; Sperm Motility; Testing; Testis; Therapeutic; Ursidae Family; Yeasts; cell motility; in vivo; male; men; protein expression; research study; rho; rho GTP-Binding Proteins; rhophilin; sperm cell; therapy development; yeast two hybrid system

DESCRIPTION (provided by applicant): Suboptimal sperm motility accounts for nearly 30% of all human infertility. As such, a better understanding of the biochemical mechanisms regulating sperm motility may provide therapeutic options for infertile couples. We have recently identified a gene product (ROPN1) that appears to be critical for both sperm motility and fertility. ROPN1 is highly expressed in testis and sperm, and mice lacking ROPN1 have impaired sperm motility and are subfertile or infertile. The expression level of ROPN1 is significantly lower in asthenozoospermic men than in normozoospermic controls. ROPN1 was originally identified as a protein that binds to rhophilin, a binding partner of Rho. Using a yeast two-hybrid analysis, we discovered that ROPN1 also binds to sperm A-kinase anchoring proteins (AKAPs). ROPN1 contains a dimerization/docking domain similar to the regulatory subunit of protein kinase A (PKA). However, outside the docking domain, ROPN1 bears little or no similarity to PKA suggesting they have distinct functions. Two observations suggest that ROPN1 is required for flagellar motility: 1) adding peptides (Ht31) that disrupt the interaction between AKAPs and ROPN1 results in altered protein phosphatase 1 (PP1) activity, GSK3 phosphorylation and arrested sperm motility, and 2) sperm from mutant mice lacking ROPN1 (Ropn1-/-) have reduced motility. Thus, ROPN1 appears to be a key molecule located at the intersection between the cAMP and Rho pathways. Although many articles have been published on the role of cAMP/PKA in sperm, the literature on Rho in sperm is relatively sparse. Inactivation of Rho-GTPase has been shown to reduce mammalian sperm motility and we have recently shown that sperm contain all the protein components of the Rho signaling pathway. Inhibition of PP1, a downstream effector in the Rho pathway, dramatically alters sperm motility. However, to our knowledge, no one has measured the activity of Rho-GTPase from sperm. The goal of this project is to determine if Rho is a critical component of the biochemical machinery regulating sperm motility and if ROPN1 functions as part of this pathway. Successful completion of this proposal will enhance our knowledge of this important regulatory mechanism and thus may facilitate development of treatments for male infertility.

描述（申请人提供）：次优的精子运动占所有人类不育的30％。因此，更好地了解调节精子运动的生化机制可能为不育夫妇提供治疗选择。我们最近确定了一种基因产物（ROPN1），这似乎对精子运动和生育至关重要。 ROPN1在睾丸和精子中高度表达，缺乏ROPN1的小鼠患有精子运动性，并且是次生或不育的小鼠。哮喘性男性的ROPN1的表达水平明显低于Normozoospermic对照中的表达水平。 ROPN1最初被鉴定为与Rho的结合伴侣Rhhophilin结合的蛋白质。使用酵母双杂交分析，我们发现ROPN1还与精子A-激酶锚定蛋白（AKAP）结合。 ROPN1包含一个类似于蛋白激酶A（PKA）的调节亚基的二聚化/对接域。但是，在对接域之外，ROPN1与PKA几乎没有相似之处，表明它们具有不同的功能。两个观察结果表明，鞭毛运动需要ROPN1：1）添加肽（HT31）破坏AKAP和ROPN1之间的相互作用会导致蛋白质磷酸酶1（PP1）活性改变，GSK3磷酸化的磷酸化，精子运动和2）Sprers cointy cottion cottion cottion cottion cottion cottion cot ropn1（ropn1）（ropn1）（ropn1）（ropn1）。因此，ROPN1似乎是位于营地和Rho途径之间的交点的关键分子。尽管已经发表了许多有关CAMP/PKA在精子中的作用的文章，但有关精子中Rho的文献相对较少。 Rho-GTPase的灭活已被证明可以降低哺乳动物的精子运动，我们最近表明精子包含Rho信号通路的所有蛋白质成分。 PP1的抑制作用，PP1是RHO途径中下游效应器的抑制作用，极大地改变了精子运动。但是，据我们所知，没有人能够测量精子中Rho-GTPase的活性。该项目的目的是确定RHO是否是调节精子运动的生化机械的关键组成部分，并且ROPN1是否功能作为该途径的一部分。该提案的成功完成将增强我们对这一重要的监管机制的了解，因此可能有助于开发男性不育治疗。