COBRE: UNR: MOLECULAR PHYSIOL & REGULATION OF VOLUME SENSITIVE CHLORIDE CHANNEL

本子项目是利用由NIH/NCRR资助的中心赠款提供的资源的众多研究子项目之一。子项目和研究者（PI）可能已经从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。列出的机构是中心的，不一定是研究者的机构。COBRE项目1将研究心脏体积调节阴离子通道的分子生理学和调控。离子通道调节的分子机制对于理解细胞如何调节其体积和理解离子通道蛋白的结构/功能关系具有重要意义。我们之前提出ClC-3，电压依赖性Cl-通道ClC超家族的成员，作为负责心脏和平滑肌细胞中天然体积调节的向外整流阴离子通道（VSOACs）的候选分子。本项目拟开展的实验将为研究氨基端氨基酸的多种蛋白激酶磷酸化在两种主要的ClC-3亚型调控中的作用提供新的思路，并利用转基因小鼠进一步研究ClC-3与天然VSOACs之间的关系，揭示其生理作用。最后将使用分子和蛋白质组学方法来鉴定构成天然VSOAC多聚体蛋白复合物的主要成分和辅助蛋白。由于心肌Cl-通道的激活可对动作电位持续时间和自动性产生显著影响，并且是细胞体积稳态的关键调节因子，因此这些通道在心律失常、心肌缺血、充血性心力衰竭和肥厚等多种心肌疾病中具有重要的临床意义。这个项目对于阐明容量敏感的Cl-通道在心脏和心血管系统中的正常生理和可能的病理生理作用具有重要的潜力。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. COBRE Project 1 will study the molecular physiology and regulation of volume-regulated anion channels in the heart. The molecular mechanism of Cl- channel regulation is an important issue for understanding how cells regulate their volume and for understanding structure/function relationships of ion channel proteins in general. We previously proposed ClC-3, a member of the ClC superfamily of voltage-dependent Cl- channels, as a molecular candidate responsible for native volume-regulated outwardly rectifying anion channels (VSOACs) in cardiac and smooth muscle cells. The experiments proposed in this project will provide new insights into the role of phosphorylation by various protein kinases of amino terminus amino acids in the regulation of the two major ClC-3 isoforms, use transgenic mice to further examine the relationship between ClC-3 and native VSOACs and reveal their physiological role, and finally will use molecular and proteomic approaches to identify the major components and accessory proteins that constitute the native VSOAC multimeric protein complex. Since the activation of cardiac Cl- channels can produce significant effects on action potential duration and automaticity, and are key regulators of cell volume homeostasis, these channels have important clinical significance for several myocardial diseases, including cardiac arrhythmias, myocardial ischemia, congestive heart failure and hypertrophy. This project has significant potential of elucidating the normal physiological and possible pathophysiological role of volume-sensitive Cl- channels in the heart and cardiovascular system.