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.

项目摘要该PPG的总体目标是定义调节局部钙的分子机制（CA2+）在正常和失败的心脏中发出信号，具有前所未有的精度。四个目标共有三个目标项目：1）探索肾上腺信号在调节正常和失败心脏中钙的确切作用； 2）定义了T管与肌质网（SR）钙通道之间相互作用的新机制； 3）对涉及钙的遗传形式的基于遗传的机制发展了新的理解。项目四通过研究肌浆和内质上存在的2型Ryanodine受体（RYR2）/钙释放通道在心力衰竭的情况下，许多细胞类型的网状（SR/ER）（慢性HF射血分数降低， HFREF）。从细胞内存储中释放Ca2+需要RYR2通道，这会触发兴奋 - 收缩（EC）在心肌中耦合。继承的RYR2突变会导致心律不齐，包括运动引起的猝死或儿茶酚胺能多态性心脏心动过速（CPVT）以及应力诱导的后 RYR2的翻译修饰有助于心力衰竭（HF）进展。在这两种情况下由于遗传突变（CPVT）或获得后翻译后修饰（HF）而被泄漏。未得到答复问题包括：1）RYR2突变可能会导致HF； 1）可以（如果是这样）； 2）什么是什么精确机制哪种PKA磷酸化激活RYR2并在HF中起作用？使用Cryo-Em的初步数据来解决〜2.4Å人类RyR2的结构表明，人CPVT突变RyR2-R2474S将通道放入一个 “底漆状态”，可以在低的，通常没有激活的[Ca2+] Cyt下从中轻松地从中受到病理的激活解释为什么这些通道在运动或压力过程中引起致命的心室心律不齐。这 Rycal Drug ARM210与RYR2结合，并将突变通道恢复为稳定的封闭状态，以防止泄漏和心律不齐。适用的假设是RYR2错义突变，其中14个已在来自巴基斯坦基因组资源（PGR）患者心肌病的斜角预测的患者，A 具有广泛表型数据和高血缘率（核心A）的独特人群可能是功能（GOF）突变的获取，该突变也将通道置于底漆状态，对此更加敏感与CPVT突变相比激活。那就是这些患者的RYR2通道泄漏并发展HF 由于SR Ca2+的耗竭，导致心脏收缩性受损。这些问题将使用功能和结构测定，并使用新型药物Rycal（ARM210），该药物固定RYR2介导的SR CA2+通过定义明确的机制泄漏。提出了三个目的：1）评估功能的变化和与心力衰竭相关的RYR2 GOF错义变体的结构（HFREF）； 2）评估Rycal对人RYR2和疾病相关变体的结构/功能； 3）检查分子机制肾上腺素信号传导在正常和失败的心脏中调节RYR2功能。