Gap Junctional Patterning in Arrhythmic Heart

心律失常心脏的间隙连接模式

基本信息

批准号：
8049732
负责人：
ROBERT G GOURDIE
金额：
$ 33.19万
依托单位：
MEDICAL UNIVERSITY OF SOUTH CAROLINA
依托单位国家：
美国
项目类别：
财政年份：
2010
资助国家：
美国
起止时间：
2010-04-01 至 2014-02-28
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8049732
关键词：
Actin-Binding Protein Actins Action Potentials Adhesions Arrhythmia Binding Biochemical Biological Assay Biological Process Biotinylation CTF1 gene Cardiac Cardiomyopathies Cell Culture Techniques Cell Line Cell membrane Cell physiology Cells Chimeric Proteins Cicatrix Clinical Coculture Techniques Communication Competence Connexin 43 Connexins Connexon Coronary artery Coupling Data Dyes Echocardiography Electrocardiogram Electrophysiology (science)Fibroblasts Frequencies Gap Junctions Goals Heart Hela Cells Heterogeneity Human Imagery Implant In Vitro Infarction Injury Left ventricular structure Life Ligation Link Manuscripts Maps Mediating Membrane Methods Molecular Morbidity - disease rate Mus Muscle Cells Myocardial Myocardial Infarction Myofibroblast Neonatal Optics Pattern Peer Review Peptides Physiological Predisposition Prevention approach Prevention therapy Process Proteins Protocols documentation Publishing Role Silicones Skin Sudden Death Surface Telemetry Testing Tight Junctions Time Tissues Transgenic Mice Translating Ventricular Remodeling Work cellular imaging in vivo insight intercellular communication loss of function mortality mutant novel novel strategies patch clamp public health relevance research study response uptake

项目摘要

DESCRIPTION (provided by applicant): Direct cytosolic communication between cells is mediated by an aggregate of intercellular channels in the plasma membrane called the gap junction (GJ). Remodeling of connexin43 (Cx43) GJs has been linked to cardiac arrhythmias. Work accomplished during the previous period of this RO1 identified a biological function of interaction between Cx43 and the actin-binding protein Zonula Occludens (ZO)-1 in GJ remodeling. In recent work, we have determined that a peptide known to inhibit Cx43/ZO-1 interaction, 1CT1, reduces the frequency of inducible arrhythmias following injury to the left ventricle. Preliminary data from work performed with 1CT1 in vitro, indicates that the transition from free connexon channels in the membrane to paired connexons in intercellular channel aggregates underlies GJ remodeling. We hypothesize that ZO-1 regulates the rate at which free connexons in the membrane accrete to GJs-the "connexon switch". The aims in this renewal will test this hypothesis and its implications for GJ intercellular communication, membrane excitability, and a novel role for Cx43 in differential adhesion between myocytes and fibroblasts following myocardial infarction - all processes likely to impact susceptibility to re-entrant arrhythmia. The proposed experiments will quantitatively determine the role of Cx43/ZO-1 interaction in the "connexon switch" using methods including live cell imaging, fluorescent fusion proteins, loss-of-function mutants, whole cell patch clamp, single channel electrophysiology and biochemical assays. Implications of Cx43/ZO-1 interaction within the physiological framework of cardiac injury in vivo will be assessed by echocardiography, EKG telemetry, optical mapping of electrical activation and arrhythmia induction protocols. The data generated will broaden our understanding of fundamental mechanisms of Cx43 function and may translate to new therapies for the prevention and treatment of cardiac arrhythmia. PUBLIC HEALTH RELEVANCE: Injury and scarring of the heart following myocardial infarction (heart attack) is one the most frequent causes of sudden death in the USA. This project will deliver new insights on the function of a protein essential to a stable heartbeat called connexin43. The project aims to provide novel approaches to the prevention and treatment of heart attacks.

描述（由申请人提供）：细胞之间的直接胞质通讯是由质膜中称为间隙连接（GJ）的细胞间通道聚集体介导的。连接蛋白 43 (Cx43) GJ 的重塑与心律失常有关。 RO1 前期完成的工作确定了 Cx43 和肌动蛋白结合蛋白闭锁小带 (ZO)-1 之间相互作用在 GJ 重塑中的生物学功能。在最近的工作中，我们确定了一种已知可抑制 Cx43/ZO-1 相互作用的肽 1CT1，可降低左心室损伤后诱发心律失常的频率。体外 1CT1 工作的初步数据表明，从膜中的游离连接子通道到细胞间通道聚集体中的配对连接子的转变是 GJ 重塑的基础。我们假设 ZO-1 调节膜中游离连接子附着到 GJ（“连接子开关”）的速率。本次更新的目的将测试这一假设及其对 GJ 细胞间通讯、膜兴奋性的影响，以及 Cx43 在心肌梗死后心肌细胞和成纤维细胞之间差异粘附中的新作用——所有过程都可能影响折返性心律失常的易感性。拟议的实验将使用活细胞成像、荧光融合蛋白、功能丧失突变体、全细胞膜片钳、单通道电生理学和生化测定等方法定量确定 Cx43/ZO-1 相互作用在“连接子开关”中的作用。将通过超声心动图、心电图遥测、电激活光学测绘和心律失常诱导方案来评估 Cx43/ZO-1 相互作用在体内心脏损伤生理框架内的影响。生成的数据将拓宽我们对 Cx43 功能基本机制的理解，并可能转化为预防和治疗心律失常的新疗法。公共卫生相关性：心肌梗塞（心脏病发作）后心脏损伤和疤痕是美国猝死的最常见原因之一。该项目将为稳定心跳所必需的连接蛋白（connexin43）的功能提供新的见解。该项目旨在提供预防和治疗心脏病的新方法。