Ryanodine receptor structure and function in heart failure

Ryanodine 受体结构和心力衰竭中的功能

基本信息

批准号：
10628917
负责人：
ANDREW Robert MARKS
金额：
$ 42.77万
依托单位：
COLUMBIA UNIVERSITY HEALTH SCIENCES
依托单位国家：
美国
项目类别：
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/10628917
关键词：
3-Dimensional Address Adrenergic Agents Affect Alanine Anti-Arrhythmia Agents Arrhythmia Back Binding Binding Sites Biological Assay Calcium Calcium Channel Calcium Signaling Calmodulin Cardiac Cardiomyopathies Catecholaminergic Polymorphic Ventricular Tachycardia Cell membrane Cells Chronic ClinVar Complex Congestive Heart Failure Consanguinity Coupling Cryoelectron Microscopy Cyclic AMP-Dependent Protein Kinases Data Defect Disease EFRAC Endoplasmic Reticulum Exercise FKBP1B gene Functional disorder Genetic Goals Heart Heart failure Human Impairment In Vitro Individual Inherited Ligands Link Location Mediating Missense Mutation Molecular Morbidity - disease rate Movement Mus Mutant Strains Mice Mutate Mutation Myocardial dysfunction Myocardium Myopathy Outcome Pakistan Pathogenesis Pathologic Patients Pharmaceutical Preparations Phenotype Phosphorylation Phosphorylation Site Physiology Post-Translational Protein Processing Pre-Clinical Model Proteins Recombinants Regulation Resolution Role RyR1 RyR2 Ryanodine Receptor Calcium Release Channel Sarcoplasmic Reticulum Signal Transduction Site Stress Structure Structure-Activity Relationship Sudden Death Testing United States National Institutes of Health Variant Ventricular Arrhythmia Work calmodulin-dependent protein kinase II cell type cofactor cohort drug discovery gain of function gain of function mutation genome resource heart function human model in vivo junctophilin mortality mouse model mutant nanobodies novel novel therapeutics oxidation phenotypic data prevent receptor function research clinical testing small molecule

项目摘要

Project Summary The overarching goal of this PPG is to define the molecular mechanisms that regulate local calcium (Ca2+) signaling in normal and failing hearts with unprecedented precision. There are three goals shared by the four projects: 1) explore the precise role of adrenergic signaling in modulating calcium in normal and failing hearts; 2) define novel mechanisms of interactions between T-tubule and sarcoplasmic reticulum (SR) calcium channels; 3) develop new understandings of genetic based mechanisms of inherited forms of CV disease involving calcium. Project four provides the essential link to SR calcium release by studying the structure-function relationships of the type 2 ryanodine receptor (RyR2)/calcium release channel present on the sarcoplasmic and endoplasmic reticula (SR/ER) of many cell types in the context of heart failure (chronic HF with reduced ejection fraction, HFrEF). RyR2 channels are required for Ca2+ release from intracellular stores that triggers excitation-contraction (EC) coupling in the cardiac muscle. Inherited RyR2 mutations can cause arrhythmias including exercise-induced sudden death or catecholaminergic polymorphic ventricular tachycardia (CPVT), and stress-induced post- translational modifications of RyR2 contribute to heart failure (HF) progression. In both cases RyR2 channels are leaky either due to inherited mutations (CPVT) or acquired post-translational modifications (HF). Unanswered questions include: 1) can (and if so how) RyR2 mutations can cause HF; 2) what is the precise mechanism by which PKA phosphorylation activates RyR2 and plays a role in HF? Preliminary data using cryo-EM to solve the structure of human RyR2 at ~2.4 Å show that a human CPVT mutation RyR2-R2474S puts the channel into a “primed state” from which it can be readily and pathologically activated at low, normally non-activating [Ca2+]cyt explaining why these channels are leaky and cause fatal ventricular arrhythmias during exercise or stress. The Rycal drug ARM210 binds to RyR2 and restores the mutant channel back to a stable closed state preventing leak and arrhythmias. The applicant hypothesizes that RyR2 missense mutations, 14 of which are found in patients with a ClinVar prediction of cardiomyopathy in patients from the Pakistan Genome Resource (PGR), a unique cohort of individuals with extensive phenotype data and high rates of consanguinity, (Core A), may be gain of function (GoF) mutations that also put the channel into a primed state which is even more sensitive to activation compared to the CPVT mutations. Thus, these patients have leaky RyR2 channels and develop HF due to depletion of SR Ca2+ resulting in impaired cardiac contractility. These questions will be addressed using functional and structural assays and using a novel drug, Rycal (ARM210), that fixes the RyR2 mediated SR Ca2+ leak via a well-defined mechanism. Three aims are proposed: 1) Evaluate changes in the function and structure of RyR2 GoF missense variants linked to heart failure (HFrEF); 2) Evaluate the effect of Rycal on the structure/function of human RyR2 and disease related variants; and 3) Examine the molecular mechanism by which adrenergic signaling regulates RyR2 function in normal and failing hearts.

项目概要该 PPG 的首要目标是定义调节局部钙 (Ca2+) 的分子机制以前所未有的精确度向正常和衰竭的心脏发出信号四人共有三个目标。项目： 1) 探索肾上腺素信号传导在正常和衰竭心脏中调节钙的精确作用； 2）定义T小管和肌浆网（SR）钙通道之间相互作用的新机制； 3）对涉及钙的遗传性心血管疾病的遗传机制有新的认识。项目四通过研究 SR 钙释放的结构与功能关系，提供了与 SR 钙释放的重要联系。存在于肌浆和内质上的 2 型兰尼碱受体 (RyR2)/钙释放通道心力衰竭（射血分数降低的慢性心力衰竭， HFrEF）需要 RyR2 通道来释放细胞内储存的 Ca2+，从而触发兴奋收缩。 (EC) 心肌中的遗传性 RyR2 突变可导致心律失常，包括运动诱发的心律失常。猝死或儿茶酚胺能多形性室性心动过速（CPVT），以及应激诱发的后遗症在这两种情况下，RyR2 通道的翻译修饰都会导致心力衰竭 (HF) 进展。由于遗传突变（CPVT）或获得性翻译后修饰（HF）而导致泄漏。问题包括：1) RyR2 突变是否可以（如果是的话，如何）引起心力衰竭；2) 其确切机制是什么？哪种 PKA 磷酸化激活 RyR2 并在 HF 中发挥作用？使用冷冻电镜解决该问题的初步数据人类 RyR2 约 2.4 Å 的结构表明，人类 CPVT 突变 RyR2-R2474S 将通道置于 “启动状态”，在低水平、通常不激活的 [Ca2+]cyt 下，它可以很容易地病理性激活解释为什么这些通道会渗漏并在运动或压力期间导致致命的室性心律失常。 Rycal 药物 ARM210 与 RyR2 结合并将突变通道恢复到稳定的关闭状态，从而防止申请人招募了 RyR2 错义突变，其中 14 个出现在来自巴基斯坦基因组资源 (PGR) 的 ClinVar 预测心肌病患者具有广泛表型数据和高血亲率的独特个体群体（核心A），可能是功能获得（GoF）突变也使通道进入启动状态，该状态对与 CPVT 突变相比，这些患者的 RyR2 通道存在渗漏并发生心力衰竭。由于 SR Ca2+ 耗尽导致心肌收缩力受损，这些问题将通过使用来解决。功能和结构分析，并使用一种新药 Rycal (ARM210)，它可以修复 RyR2 介导的 SR 通过明确的机制进行 Ca2+ 泄漏提出了三个目标：1）评估功能的变化和与心力衰竭 (HFrEF) 相关的 RyR2 GoF 错义变异的结构；2) 评估 Rycal 对人类 RyR2 的结构/功能和疾病相关变异；以及 3) 检查分子机制肾上腺素能信号调节正常和衰竭心脏中的 RyR2 功能。