Elucidation of the Role of a Novel Cardiac Micropeptide in the Control of Heart Function and Dysfunction

阐明新型心脏微肽在控制心脏功能和功能障碍中的作用

基本信息

批准号：
9205181
负责人：
Catherine A Makarewich
金额：
$ 5.71万
依托单位：
UT SOUTHWESTERN MEDICAL CENTER
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-02-01 至 2019-01-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9205181
关键词：
Amino Acids Animals Binding Biochemical Biological Assay Ca(2+)-Transporting ATPase Calcineurin Calcium Cardiac Cardiac Myocytes Cardiovascular Diseases Cause of Death Cells Cessation of life Characteristics Chronic Clinical Confocal Microscopy Coupling DNA Sequence Defect Depressed mood Developed Countries Developing Countries Development Dilated Cardiomyopathy Disease Disease Progression Disease model Disease susceptibility Electron Microscopy Epidemic Event Expenditure Financial compensation Genes Goals Healthcare Heart Heart Abnormalities Heart Diseases Heart failure Homeostasis Human Human Characteristics Impairment In Vitro Integral Membrane Protein Knockout Mice Lead Mass Spectrum Analysis Measurement Mediating Membrane Methodology Molecular Morbidity - disease rate Mus Muscle Muscle Cells Muscle relaxation phase Myocardial dysfunction Names Open Reading Frames PPP3CA gene Pathologic Pathologic Processes Patients Peptides Performance Physiological Physiological Processes Plant Genome Prevalence Property Protein phosphatase Proteins Public Health Pump RNA Regulation Regulatory Pathway Relaxation Role Sarcoplasmic Reticulum Sequence Homology Signal Transduction Skeletal Muscle Structure Systole Systolic heart failure Testing Therapeutic Untranslated RNA Yeasts adeno-associated viral vector base disability gene therapy genetic approach heart function in vivo inhibitor/antagonist insight mortality neglect new therapeutic target novel novel therapeutics overexpression phospholamban pressure public health relevance response sarcolipin yeast two hybrid system

项目摘要

DESCRIPTION (provided by applicant): Cardiovascular disease (CVD) is the leading cause of death and disability in industrialized nations and its prevalence is rising rapidly in developing nations. In particular, heart failure (HF) has been singled out as an epidemic and is a staggering clinical and public health problem associated with significant morbidity, mortality, and healthcare expenditures. Current therapies only delay morbidity and mortality in patients with chronic systolic heart failure, as disease progression typically continues unabated resulting in death. Novel therapies for heart failure are desperately needed, which will require a greater understanding of the underlying molecular mechanisms that underlie this disease. A universal characteristic of the failing heart is impaired Ca2+ cycling through the sarcoplasmic reticulum (SR), the major internal store of Ca2+ in cardiomyocytes. Indeed, cardiomyocytes from failing hearts consistently show defective excitation contraction-coupling characterized by diminished SR Ca2+ sequestration and decreased intracellular Ca2+ transients, events that contribute to impaired contractility and relaxation that culminate in depressed pumping action of the heart. Ca2+ re- sequestration into the SR is mediated by a Ca2+-ATPase (SERCA), whose activity is known to be reversibly regulated by the small integral membrane proteins phospholamban (PLN) and sarcolipin (SLN). Enhancing SERCA activity and function has been suggested as an important clinical approach for treating HF by loading the SR with greater Ca2+ levels to augment Ca2+ release resulting in greater myocyte contractility during systole. Apart from gene therapy to actually replace SERCA protein (which is currently in human clinical trails with an AAV vector), we currently lack a facile therapeutic approach aimed at correcting alterations in Ca2+ and SERCA function in the heart. However, modulation of SERCA activity through manipulation of PLN or small peptides like it represents a novel and straightforward therapeutic approach. Our lab has identified a novel micropeptide encoded by a muscle-specific RNA currently annotated as a long non-coding RNA (lncRNA), which we have named DWORF (DWarf Open Reading Frame). DWORF shares strong sequence homology and predicted domain structure with the well-described SERCA inhibitors PLN and SLN and our preliminary results show it localizes to the SR and can bind directly to SERCA. We hypothesize that DWORF is functionally homologous to PLN and SLN and that it regulates SERCA activity and myocyte contractility. We will utilize biochemical, cell-based, and genetic approaches, along with in vivo physiological studies to define the function and regulation of DWORF in the heart and to examine how it might impact cardiac disease susceptibility. Collectively, our studies will provide new insights into Ca2+ cycling and regulation in the heart and potentially provide the basis for development of a novel therapeutic target in cardiovascular disease.

描述（由申请人提供）：心血管疾病（CVD）是工业化国家死亡和残疾的主要原因，其患病率在发展中国家迅速上升，特别是心力衰竭（HF）已被列为一种流行病，并且正在流行。与显着的发病率、死亡率和医疗保健相关的令人震惊的临床和公共卫生问题目前的治疗方法只能延缓慢性收缩性心力衰竭患者的发病率和死亡率，因为疾病进展通常会持续不减，从而导致死亡，因此迫切需要针对心力衰竭的新疗法，这需要更好地了解其背后的分子机制。衰竭心脏的一个普遍特征是肌浆网 (SR) 中的 Ca2+ 循环受损，而肌浆网是心肌细胞中 Ca2+ 的主要内部储存。事实上，衰竭心脏的心肌细胞始终表现出缺陷。兴奋收缩耦合的特征是 SR Ca2+ 隔离减少和细胞内 Ca2+ 瞬变减少，这些事件导致收缩性和松弛受损，最终导致心脏的 Ca2+ 重新隔离到 SR 中，这是由 Ca2+-ATP 酶 (SERCA) 介导的。），已知其活性受到小整合膜蛋白受磷蛋白（PLN）和肌磷脂（SLN）的可逆调节。增强 SERCA 活性和功能已被认为是治疗心力衰竭的重要临床方法，除了基因治疗以实际替代 SERCA 蛋白（目前正在研究中）之外，还可以通过在 SR 上加载更高的 Ca2+ 水平来增加 Ca2+ 释放，从而导致收缩期期间更大的心肌细胞收缩力。 AAV 载体的人类临床试验），我们目前缺乏一种旨在纠正心脏中 Ca2+ 和 SERCA 功能改变的简便治疗方法，但是，通过操纵 PLN 或小分子来调节 SERCA 活性。我们的实验室发现了一种由肌肉特异性 RNA 编码的新型微肽，目前被注释为长非编码 RNA (lncRNA)，我们将其命名为 DWORF（DWarf 开放阅读框）。 DWORF 与众所周知的 SERCA 抑制剂 PLN 和 SLN 具有很强的序列同源性和预测的结构域结构，我们的初步结果表明它定位于 SR 并且可以直接与 SERCA 结合。 DWORF 在功能上与 PLN 和 SLN 相似，并且它调节 SERCA 活性和心肌细胞收缩力。我们将利用生化、细胞和遗传学方法以及体内生理学研究来定义 DWORF 在心脏中的功能和调节。总的来说，我们的研究将为心脏中的 Ca2+ 循环和调节提供新的见解，并可能为开发心血管疾病的新治疗靶点奠定基础。