Gap Junctional Patterning in Arrhythmic Heart

心律失常心脏的间隙连接模式

• 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
• 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

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信是由称为间隙连接（GJ）的质膜中细胞间通道的聚集体介导的。 Connexin43（CX43）GJS的重塑已与心律不齐有关。在此RO1的上一个时期完成的工作确定了CX43与肌动蛋白结合蛋白齐原子闭塞（ZO）-1之间相互作用的生物学功能。在最近的工作中，我们确定已知可抑制CX43/ZO-1相互作用的肽1CT1降低了左心室损伤后诱导性心律不齐的频率。在体外用1CT1进行的工作的初步数据表明，从膜中的自由连接通道过渡到细胞间通道聚集体中的配对连接子是GJ重塑的基础。我们假设ZO-1调节膜胶中的自由连接速率到GJS-GJS-“ Connexon Switch”。这种续签的目的将检验该假设及其对GJ细胞间交流，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上的差异作用 - 所有过程可能会影响重新进入势力的所有过程。提出的实验将使用包括活细胞成像，荧光融合蛋白，功能障碍突变体，全细胞斑块夹，单个通道电生理学和生物化学分析在内的方法定量确定CX43/ZO-1相互作用在“连接开关”中的作用。 CX43/ZO-1相互作用在体内心脏损伤生理框架内的影响将通过超声心动图，EKG遥测，电激活的光学映射和心律失常诱导方案进行评估。产生的数据将扩大我们对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：心肌梗塞后心脏的伤害和心脏疤痕是美国突然死亡最常见的原因之一。该项目将对稳定的心跳蛋白质的功能提供新的见解，称为Connexin43。该项目旨在为预防和治疗心脏病发作提供新颖的方法。