Calcineurin compartmentation and regulation of pathological cardiac remodeling

钙调神经磷酸酶的划分和病理性心脏重塑的调节

• 批准号: 10231978
• 负责人: Michael Seth Kapiloff
• 金额: $ 53.06万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-04-01 至 2025-03-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10231978
• 关键词: Adrenergic Agents; Adult; Agonist; Allosteric Site; Angiotensins; Attenuated; Binding; Ca(2+)-Transporting ATPase; Calcineurin; Calmodulin; Cardiac; Cardiac Myocytes; Cell membrane; Cell physiology; Cells; Clinical; Complex; Contracts; Coronary artery; Coupling; Data; Dependovirus; Diagnosis; Diffuse; Diglycerides; Distal; Elements; Enzymes; Exhibits; Family; Fluorescence Resonance Energy Transfer; G Protein-Coupled Receptor Signaling; G-Protein-Coupled Receptors; Gene Targeting; Genetic; Guanosine Triphosphate Phosphohydrolases; Heart; Heart Hypertrophy; Heart failure; Hypertrophy; Image; Immunosuppressive Agents; In Vitro; Ion Channel; Ischemia; Knockout Mice; Left; Ligation; Mediating; Membrane; Membrane Proteins; Modeling; Monomeric GTP-Binding Proteins; Mus; Muscle Cells; Myocardial Infarction; Myocardial Ischemia; N-terminal; NFAT Pathway; Operative Surgical Procedures; Pathologic; Phosphoric Monoester Hydrolases; Phosphoserine; Prevention; Protein Isoforms; Proteins; Pump; RHO Effector Domain; RNA Interference; Rattus; Regimen; Regulation; Reperfusion Injury; Reperfusion Therapy; Reporter; Role; Sarcomeres; Scaffolding Protein; Second Messenger Systems; Signal Pathway; Signal Transduction; Source; Specificity; Stains; Stress; Structure; Syndrome; TRIP10 gene; Testing; Therapeutic; Threonine; VIVIT peptide; Ventricular; Vesicle; beta-adrenergic receptor; calcineurin phosphatase; cardiogenesis; cdc42 GTP-Binding Protein; experimental study; functional independence; heart function; improved; inhibitor/antagonist; insight; member; mortality; mutant; myocardial injury; new therapeutic target; novel; novel therapeutic intervention; novel therapeutics; polyproline; pressure; receptor; recruit; response; rho; sensor; theories; therapeutic target

The Ca2+/calmodulin-dependent phosphatase calcineurin (CaN, PP2B) is a pleiotropic signaling enzyme important for the regulation of cardiac hypertrophy. While CaN inhibition will attenuate pathological cardiac remodeling, therapeutic targeting of CaN is problematic as clinically established CaN inhibitors are immunosuppressant and as CaN targeting can worsen myocardial injury due to ischemia/reperfusion. In theory, however, if CaN signaling pathways mediating pathological cardiac hypertrophy could be targeted in isolation, a new therapeutic paradigm could be established. Two isoforms of CaNA, α and β, are expressed as proteins equally in the heart, and yet genetic targeting of CaNAβ (PPP3cb) is sufficient to blunt pathological hypertrophy in mice. We recently discovered that CaNAβ2 is targeted through its unique N-terminal polyproline (PP) domain to a myocyte compartment organized by the scaffold protein Cdc4-Interacting Protein 4 (CIP4, TRIP10). Imaging using Forster Resonance Energy Transfer (FRET) reporters revealed that CIP4-bound CaNAβ2 is activated by G-protein coupled receptor signaling, including angiotensin II, α- and β-adrenergic receptors, but not by pacing that induces myocyte contraction. Notably, both CIP4 gene targeting and adeno-associated virus-mediated PP- domain anchoring disruption inhibited cardiac remodeling and improved cardiac function in response to pressure overload. Thus, CaNAβ PP-dependent anchoring constitutes a novel mechanism for specification of CaN function, providing an explanation for the specific role of CaNAβ in the cardiac myocyte, as well as for the important question why hypertrophic CaN signaling is not active in normal contracting myocytes. In this project, we will test the novel hypothesis that in the cardiac myocyte PP-domain anchoring and CIP4 compartmentation confer CaNAβ2 action selectively promoting pathological cardiac hypertrophy, thereby comprising a new therapeutic target for the prevention and/or treatment of heart failure. Specific Aim 1: Localization and function of the CIP4 signaling compartment. This Aim will define CIP4 localization in the myocyte, study the relevance of the various CIP4 domains for myocyte hypertrophy, and explore whether CIP4-associated CaNAβ2 acts locally or distally from CIP4 complexes to promote hypertrophy. Specific Aim 2: Regulation of Ca2+ in the CIP4-CaNAβ2 compartment. Functional independence of a Ca2+ signaling compartment requires mechanisms for both local influx of Ca2+ and for insulating the compartment against elevations in Ca2+ associated with other cellular functions. In this Aim, we will define the source of Ca2+ and how this compartment is insulated using live myocyte imaging. Specific Aim 3: PP-anchored CaNAβ and ischemic heart disease. This aim will test whether targeting of PP-anchored CaNAβ can attenuate the development of heart failure without worsening myocyte survival in ischemic heart disease, These Aims will elucidate how PP-domain-mediated anchoring CaNAβ confers activation within a novel Ca2+ compartment, providing both novel insights regarding specificity in phosphatase signal transduction and further evidence supporting a novel therapeutic approach for heart failure.

Ca2+/钙调蛋白依赖性磷酸酶钙调蛋白（CAN，PP2B）是一种多效信号酶 对心脏肥大的调节很重要。虽然可以抑制会减弱病理心脏 重塑，治疗靶向罐头是有问题的，因为临床确定的抑制剂是 免疫抑制剂和靶向可能会因缺血/再灌注而使心肌损伤恶化。从理论上讲 但是，如果可以隔离地介导病理心脏肥大的信号通路，则可以孤立地针对 可以建立新的治疗范式。 CANA，α和β的两个同工型表示为蛋白质 同样在心脏中，但CANAβ（PPP3CB）的遗传靶向足以钝化病理肥大 在老鼠中。我们最近发现CANAβ2通过其独特的N末端多生（PP）结构域靶向 到由支架蛋白Cdc4相互作用蛋白4（CIP4，TRIP10）组织的肌细胞室。成像 使用Forster共振能量转移（FRET）报告者表明，CIP4结合的CANAβ2被激活 G蛋白偶联受体信号传导，包括血管紧张素II，α-和β-肾上腺素受体，但不是通过起搏 这会影响心肌收缩。值得注意的是，CIP4基因靶向和腺相关病毒介导的PP- 锚定锚定抑制了心脏重塑和改善心脏功能，以应对压力 超载。那就是CANAβPP依赖性锚定构成了一种新的罐头规范机制 功能，为CANAβ在心肌细胞中的特定作用提供了解释，以及 重要的问题为什么肥厚的可以信号在正常收缩肌细胞中不活跃。在这个项目中， 我们将测试新的假设，即心肌细胞PP - 域锚定和CIP4隔室 会议CANAβ2动作有选择地促进病理心脏肥大，从而完成了新的 预防和/或心力衰竭治疗的治疗靶标。特定目标1：本地化和 CIP4信号隔室的功能。该目标将定义肌细胞中的CIP4定位，研究 各种CIP4结构域与肌细胞肥大的相关性，并探索CIP4相关的CANAβ2是否相关 与CIP4复合物局部或分开作用以促进肥大。特定目的2：CA2+的调节 CIP4-CANAβ2室。 CA2+信号舱的功能独立性需要机制 对于Ca2+的局部影响，以及与其他相关的Ca2+高程的绝缘室 细胞功能。在此目标中，我们将定义Ca2+的来源以及如何使用Live隔离该隔室 心肌成像。特定目标3：PP锚定的CANAβ和缺血性心脏病。这个目标将测试 靶向PP锚定的CANAβ是否可以减弱心力衰竭的发展而不担心 肌细胞在缺血性心脏病中的生存，这些目标将阐明PP域介导的锚定 CANAβ赋予了新型Ca2+室内的激活，提供了有关特异性的两种新见解 磷酸酶信号转移和进一步的证据支持一种新型的心力衰竭治疗方法。