Illuminating the function regulome of cardiac L-type Ca2+ channels in health and disease

阐明心脏 L 型 Ca2 通道在健康和疾病中的功能调节组

• 批准号: 10628916
• 负责人: Manu Ben Johny
• 金额: $ 44.28万
• 依托单位: COLUMBIA UNIVERSITY HEALTH SCIENCES
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-05-15 至 2028-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10628916
• 关键词: Acceleration; Action Potentials; Adrenergic Agents; Adult; Animals; Arrhythmia; Atrial Fibrillation; Binding; Calcium Channel; Calmodulin; Cardiac; Cardiac Myocytes; Cardiomyopathies; Cell physiology; Cells; Collaborations; Complex; Coupling; Data; Defect; Development; Dilated Cardiomyopathy; Disease; Electrophysiology (science); Fluorescence Resonance Energy Transfer; Functional disorder; Genetic Transcription; Health; Heart; Heart Diseases; Heart failure; Human; Hybrids; Hypertrophic Cardiomyopathy; Impairment; In Vitro; Individual; Knockout Mice; Leucine-Rich Repeat; Life; Link; Macromolecular Complexes; Mediating; Molecular; Morphology; Mus; Mutation; Neighborhoods; Pakistan; Pathogenesis; Pharmaceutical Preparations; Phenotype; Physiological; Physiology; Probability; Proteins; Proteomics; Regulation; Reporter; Role; RyR2; Signal Transduction; Structure; Testing; Variant; Work; biophysical analysis; cardiometabolism; cohort; experimental study; genetic regulatory protein; genome resource; genome sequencing; junctophilin; link protein; loss of function mutation; next generation; novel; novel therapeutics; phenotypic data; recruit; screening; small hairpin RNA; trafficking

PROJECT SUMMARY CaV1.2 channels and their modulation are fundamentally important for the normal function and pathophysiology of the heart. Disruption of CaV1.2 function and regulation results in electrical and Ca2+ disturbances that underlie life-threatening cardiac diseases including arrhythmias, cardiomyopathies, and heart failure. CaV1.2 serves as the primary portal for Ca2+ influx into cardiomyocytes that initiates excitation-contraction coupling, sculpts the action potential morphology, underlies inotropy, and supports activity-dependent gene transcription. To fulfill diverse cellular functions, CaV1.2 channels recruit a rich repertoire of regulatory proteins, yielding heterogeneous macromolecular complexes. In this regard, the CaV1.2 auxiliary subunits (α2δ and β2) and various regulatory proteins have emerged as key players in orchestrating trafficking, gating, and adrenergic regulation. Recent work using proximity proteomics suggests that the CaV1.2 neighborhood extends beyond these well-studied subunits. Yet, how the non-canonical interacting proteins tune CaV1.2 function, and how alterations in channel regulation contribute to pathophysiology are largely unknown. This gap impairs forward progress in our understanding of CaV1.2 in cardiac physiology and thwarts the development of new therapies. Thus, the overall objective of this project within the PPG is to construct a next-generation blueprint of functionally- relevant cardiac CaV1.2 modulators, and to determine the contribution of channel mis-regulation by non-canonical regulators in heart failure. We develop a novel functional screening approach to systematically identify potential CaV1.2 modulators. We further undertake extensive mechanistic analysis of two non-canonical CaV1.2 modulators―Leucine rich repeat containing protein 10 (Lrrc10) and Junctophilin-2 (Jph2), both linked to cardiomyopathies and heart failure. In addition, we leverage the Pakistan Genome Resource which provides genome sequencing data and deep cardio-metabolic phenotyping of individuals with loss-of-function mutations in both Lrrc10 and Jph2 to discern the function importance of the proteins to human physiology. The three specific aims are: (1) Identify functionally-relevant non-canonical modulators of CaV1.2. (2) Elucidate the mechanism of Lrrc10 modulation of CaV1.2 and effects of DCM-linked mutations. (3) Identify mechanism of Jph2 modulation of CaV1.2 and effects of human mutations.

项目摘要 CAV1.2通道及其调节对于正常功能至关重要， 心脏的病理生理学。 CAV1.2功能和调节的破坏导致电气和 CA2+灾难是威胁生命的心脏病，包括心律不齐， 心肌病和心力衰竭。 Cav1.2是Ca2+影响力的主要门户 启动兴奋 - 收缩耦合的心肌细胞雕刻动作电位 形态学，肌力基础，并支持活动依赖性基因转录。实现 CAV1.2通道的多种细胞函数募集了丰富的调节蛋白曲目，产生 异质大分子复合物。在这方面，CAV1.2辅助亚基（α2δ和 β2）和各种调节蛋白已成为策划贩运的关键参与者， 门控和肾上腺素调节。最近使用接近度蛋白质组学的工作表明 CAV1.2社区延伸超出了这些良好的亚基。但是，非典型的 相互作用的蛋白质调整CAV1.2功能，以及通道调节中的变化如何促进 病理生理学在很大程度上未知。这个差距会损害我们对 CAV1.2心脏生理学和阻碍新疗法的发展。那，总体 该项目在PPG中的目的是构建功能功能的下一代蓝图 相关心脏CAV1.2调节剂，并确定通道错误调节的贡献 通过心力衰竭中的非经典调节剂。我们开发了一种新型的功能筛选方法 系统地识别潜在的CAV1.2调节器。我们进一步进行广泛的 两个非典型CAV1.2调节剂 - 亮氨酸富含重复的机械分析，含有 蛋白10（LRRC10）和封闭蛋白-2（JPH2）都与心肌病和心力衰竭有关。 此外，我们利用提供基因组测序的巴基斯坦基因组资源 两者中具有功能丧失突变的个体的数据和深度心代谢表型 LRRC10和JPH2辨别蛋白质对人体生理学的功能重要性。三个 具体目的是：（1）识别CAV1.2的与功能相关的非传统调节剂。 （2） 阐明了CAV1.2的LRRC10调制机制以及DCM连接突变的作用。 （3）确定CAV1.2调制的JPH2调节机制和人类突变的作用。