The Role of CIC-6 in Vascular Control of Blood Pressure

项目概要 近一半的美国成年人患有高血压，这使得他们患中风、血管疾病的风险增加 损害、心脏病发作、心力衰竭和肾脏疾病。最近的全基因组关联研究已将 CLCN6 基因中的一些突变可降低高血压和中风风险。 CLCN6 编码 电压敏感氯离子通道 6 (ClC-6)。迄今为止，人们对 ClC-6 功能或其作用知之甚少 血压稳态。该提案的总体目标是建立生理学和分子学 ClC-6 对血管平滑肌细胞 (VSMC) 功能和血压的作用。 指导阶段：初步数据表明，ClC-6 在高尔基体中表达 VSMC 的数量。我假设 VSMC 中的 ClC-6 活性通过提供 Ca2+吸收的电荷平衡，从而维持膜的电中性。这通过发生 与高尔基体特异性 Ca2 -ATP 酶、SPCA1 和 ClC-6 损失的关联会减少高尔基体 Ca2 储存 和信号传导，改变 VSMC 收缩性。具体目标 1. 确定 ClC-6 对高尔基体 Ca2 的作用 VSMC 中的处理。我将利用平面脂质双层电生理学和复杂的 Ca2 成像来 确定 ClC-6 氯通道特性及其对高尔基体 Ca2 存储能力的影响。 此外，这些实验将为高尔基体特异性 Ca2 释放在 VSMC 中的作用提供第一个证据 Ca2 对血管收缩和扩张刺激的反应，此前从未被研究过。 独立阶段：该项目的这一阶段将制定独立的调查路线 ClC-6 对 VSMC 功能的分子影响。从这些实验中获得的见解将进一步解释 ClC-6 调节血压控制的生理机制。我的初步数据有 确定 ClC-6 可以预防或减缓高血压发展过程中的大动脉血管硬化。我会 进一步考察ClC-6对细胞增殖、迁移、凋亡以及细胞外基质蛋白的影响 沉积在正常血压和高血压血管中。我假设 ClC-6 的损失会减少 细胞外基质蛋白分泌并减缓细胞增殖，从而减少高血压诱发 纤维化和中膜增厚。这些变化将导致动脉硬化和血管消失 重塑，并降低外周血管阻力，为 ClC-6 如何调节提供了理论依据 血压。具体目标 2. 阐明 ClC-6 对血管硬度和血管重塑的影响 高血压期间。解决这一假设的实验将包括各种各样的实验， 包括脉搏波速度测量、组织学分析、迁移测定、肌动描记、隧道和 BrdU 测定和转录组分析。这些研究将有助于我们了解蛋白质的功能 通过在分子、细胞和全身水平上定义该通道在脉管系统中的作用。

PROJECT SUMMARY Nearly half of the US adult population has hypertension, which puts them at increased risk for stroke, vascular damage, heart attack, heart failure, and kidney disease. Recent genome-wide association studies have linked a number of mutations in the gene, CLCN6, to reduced hypertension and stroke risk. CLCN6 encodes the voltage-sensitive chloride channel 6 (ClC-6). To date, very little is known of about the function ClC-6, or its role in blood pressure homeostasis. The overall goal of this proposal is to establish the physiological and molecular roles of ClC-6 on vascular smooth muscle cell (VSMC) function and blood pressure. Mentored Phase: Preliminary data have demonstrated that ClC-6 is expressed in the Golgi apparatus of VSMCs. I hypothesize that ClC-6 activity in VSMCs regulates luminal Golgi Ca2+ stores by providing a charge balance for Ca2+ uptake, thereby maintaining membrane electroneutrality. This occurs through an association with the Golgi-specific Ca2+-ATPase, SPCA1, and loss of ClC-6 reduces Golgi Ca2+ stores and signaling, which alters VSMC contractility. Specific Aim 1. Establish the role of ClC-6 on Golgi Ca2+ handling in VSMCs. I will utilize planar lipid bilayer electrophysiology and sophisticated Ca2+ imaging to determine ClC-6 chloride channel properties and their impact on the Ca2+ storage capacity of the Golgi. Furthermore, these experiments will provide the first evidence of the role of Golgi-specific Ca2+ release in VSMC Ca2+ handling in response to vasocontraction and dilation stimuli, which has never before been examined. Independent Phase: This phase of the project will develop an independent line of investigation into the molecular effects of ClC-6 on VSMC function. Insight gained from these experiments will further explain the physiological mechanism underlying ClC-6 regulation of blood pressure control. My preliminary data have established that ClC-6 prevents or slows large artery vessel stiffening during development of hypertension. I will further examine the effect of ClC-6 on cellular proliferation, migration, apoptosis, and extracellular matrix protein deposition in normotensive and hypertensive vessels. I hypothesize that loss of ClC-6 will reduce extracellular matrix protein secretion and slow cell proliferation, thereby reducing hypertension induced fibrosis and media thickening. These changes will result in abrogated arterial stiffening and vessel remodeling, and reduce peripheral vascular resistance, providing a rationale for how ClC-6 moderates blood pressure. Specific Aim 2. Elucidate the influence of ClC-6 on vascular stiffness and vessel remodeling during hypertension. Experiments to address this hypothesis will include a diverse range of experiments, including pulse-wave velocity measurements, histological analyses, migration assays, myography, TUNNEL and BrdU assays, and transcriptomic analysis. These studies will inform our understanding of the protein's function by defining the role of this channel in vasculature at the molecular, cellular, and systemic levels.