Interaction of Na+/K+-ATPase With It's Signaling Partners

Na /K -ATP 酶与其信号传导伙伴的相互作用

• 批准号: 7664209
• 负责人: Zijian Xie
• 金额: $ 29.64万
• 依托单位: UNIVERSITY OF TOLEDO HEALTH SCI CAMPUS
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-04-15 至 2014-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7664209
• 关键词: 1-Phosphatidylinositol 3-Kinase; ATP phosphohydrolase; Abbreviations; Binding; Blood Pressure; Cardiac; Cardiac Glycosides; Cardiac Myocytes; Cardiovascular Diseases; Cardiovascular system; Cells; Complex; Congestive Heart Failure; Corticotropin; Cyan Fluorescent Protein; Diastolic blood pressure; Digitalis preparation; Disease; Elements; Epidermal Growth Factor Receptor; Fluorescence Resonance Energy Transfer; Focal Adhesion Kinase 1; G Protein-Coupled Receptor Genes; G-Protein-Coupled Receptors; Glutathione S-Transferase; Goals; Green Fluorescent Proteins; Heart; Knock-out; Lactate Dehydrogenase; Ligands; Lipids; Maps; Mediating; Molecular; Myocardial Ischemia; N Domain; Na(+)-K(+)-Exchanging ATPase; Nucleotides; Ouabain; PTK2 gene; Peptides; Performance; Pharmacology; Phospholipase C; Phosphotransferases; Play; Preparation; Principal Investigator; Protein Kinase; Protein Kinase C; Protein Tyrosine Kinase; Protein-Serine-Threonine Kinases; Proteins; Pump; RNA Interference; Reactive Oxygen Species; Receptor Protein-Tyrosine Kinases; Receptor Signaling; Regulation; Reperfusion Injury; Role; Sarcoplasmic Reticulum; Second Messenger Systems; Signal Transduction; Signal Transduction Pathway; Small Interfering RNA; Src peptide; Testing; Therapeutic; Time; Tissues; Transducers; Transgenic Animals; Tyrosine Phosphorylation; base; cell growth; cell growth regulation; extracellular; inhibitor/antagonist; insight; marinobufagenin; novel; novel therapeutic intervention; receptor; second messenger; src Homology Region 2 Domain; src-Family Kinases

Digitalis drugs (cardiac glycosides, cardiotonic steroids) have been valuable for the management of heart failure and cardiac arrhythmias. Recent studies have demonstrated that the Na/K-ATPase has a novel receptor function in addition to its well described pumping function; i.e., in response to a ligand-like effect of a digitalis compound, Na/K-ATPase activates protein tyrosine kinases. Specifically, we have shown that Na/K-ATPase directly interacts with Src to form a functional digitalis receptor, and ouabain binding to this receptor stimulates the associated Src kinase. This, in turn, results in the increased protein tyrosine phosphorylation and recruitment of protein kinases and lipid kinases to form a functional signalosome that transmits the ouabain signal to different intracellular compartments. Concomitantly, activation of this receptor also induces endocytosis of the signalosome which may terminate the signaling events, or exert various intracellular effects. Moreover, we have recently mapped the interaction domains between the or subunit of Na/K-ATPase and Src. These interactions illustrate a unique and Na/K-ATPase-specific cellular mechanism of Src regulation. Furthermore, we have been able to target the identified interacting domains, and have developed a cci-specific peptide that disrupts the formation of Na/K-ATPase/Src receptor complex and inhibits Src activity. This application is built upon these new discoveries and preliminary findings, and is aimed to further delineate the molecular interactions that constitute the formation of the Na/K-ATPase/Src receptor complex, and to evaluate the functionality of this receptor in digitalis-activated signal transduction. To accomplish these goals, we propose the following three Specific Aims. First, we will test the hypothesis that the formation of a functional Na/K-ATPase/Src receptor complex requires a pair of interactions involving the Na/K-ATPase a, A-domain/Src SH2 domain, and the a, N-domain/Src kinase domain. Second, we will develop and employ cell permeable Na/K-ATPase-specific Src inhibitors/activators to test the hypothesis that activation of the Na/K-ATPase/Src receptor is responsible for the pharmacological/signaling actions of ouabain in the heart. Finally, we will employ genetically modified animal models to further evaluate the functionality of the Na/K-ATPase/Src receptor complex in the heart. The results of these studies will provide new insights into the molecular mechanism of Na/K-ATPase-mediated signal transduction and digitalis pharmacology. Moreover, with a better understanding of these new cellular signaling mechanisms, new targets for developing effective therapeutic interventions for the treatment or prevention of human diseases, including cardiac dysfunctions, may be established.

洋地黄类药物（强心苷、强心类固醇）对心脏病的治疗有价值 衰竭和心律失常。最近的研究表明，Na/K-ATP酶具有一种新的 受体功能除了其充分描述的泵送功能之外;即，响应于配体样效应， 一种洋地黄化合物，Na/K-ATP酶激活蛋白酪氨酸激酶。具体来说，我们已经证明， Na/K-ATP酶直接与Src相互作用形成功能性洋地黄受体，哇巴因与此结合 受体刺激相关的Src激酶。这反过来又导致蛋白质酪氨酸增加， 磷酸化和募集蛋白激酶和脂质激酶以形成功能性信号体， 将哇巴因信号传递到不同的细胞内区室。与此同时，激活这个 受体还诱导信号体的内吞作用，这可能终止信号事件，或发挥 各种细胞内效应。此外，我们最近绘制了或 Na/K-ATP酶亚基和Src.这些相互作用说明了一个独特的和Na/K-ATP酶特异性的细胞 Src调控机制。此外，我们已经能够靶向所识别的相互作用域， 并开发了一种cci特异性肽，其破坏Na/K-ATP酶/Src受体复合物的形成 并抑制Src活性。这项应用是建立在这些新发现和初步发现的基础上， 目的是进一步描述构成Na/K-ATP酶/Src形成的分子相互作用 受体复合物，并评估该受体在洋地黄激活的信号转导中的功能。 为了实现这些目标，我们提出以下三个具体目标。首先，我们将测试假设 Na/K-ATP酶/Src受体复合物的形成需要一对相互作用， Na/K-ATP酶α，A-结构域/Src SH 2结构域和α，N-结构域/Src激酶结构域。二是 开发和使用细胞渗透性Na/K-ATP酶特异性Src抑制剂/激活剂来测试以下假设： Na/K-ATP酶/Src受体的激活负责以下的药理学/信号传导作用： 哇巴因在心脏里最后，我们将采用转基因动物模型进一步评估 Na/K-ATP酶/Src受体复合物在心脏中的功能。这些研究的结果将提供 Na/K-ATP酶介导的信号转导分子机制与洋地黄 药理学此外，随着对这些新的细胞信号传导机制的更好理解， 开发用于治疗或预防人类疾病的有效治疗干预措施的目标， 包括心脏功能障碍。