CHLORIDE AND OSMOLYTES AND VOLUME REGULATION

描述：细胞体积调节对整个细胞至关重要 动态平衡，在各种病理情况下发挥作用，如 昏迷、浮肿、中风和糖尿病。该提案结合使用了 电生理、荧光和共聚焦显微镜与分子 解决阴离子、渗透调节物质的生理作用的生物技术 而细胞骨架在体积调节中。重点放在一个 体积调节阴离子电导(VRAC)，它是普适的 机械敏感离子通道家族。这种电导存在于一种 多种细胞类型，并与从细胞中恢复有关 许多细胞中的肿胀，包括淋巴细胞，模型系统用于 这些研究。 这一建议解决了几个旨在理解 调节这一体积调节的阴离子电导及其贡献 通过同时测量对细胞体积调节的电导 低渗环境中的电流幅度和细胞肿胀。 具体讨论的是体积调节阴离子电流的假设 活性受细胞内的组成和浓度的调节 渗透剂。电流和体积测量将与分子测量相结合 生物技术来解决这样一种假设，即这种活动 电流也受一种小的胞浆肌动蛋白结合蛋白的调节， 称为ICLN。肌动蛋白细胞骨架的变化，为细胞提供 结构也与调节细胞体积有关，并已被 建议作为机械换能器来激活阴离子电流。这 假说将用两种蛋白质，BotC2和明胶蛋白来改变 F-肌动蛋白和G-肌动蛋白之间的平衡及其对肌动蛋白的影响 电流激活和细胞肿胀的电生理学，分子 和荧光技术。成功完成这项提案将 使您更好地了解 细胞内的机械转导及其在体积调节中的作用 正常和病理状态。

DESCRIPTION: Cell volume regulation is critical to overall cellular homeostasis and plays a role in a variety of pathological situations such as coma, edema, stroke and diabetes. This proposal uses a combination of electrophysiological, fluorescent and confocal microscopy and molecular biology techniques to address the physiological role of anions, osmolytes and the cytoskeleton in volume regulation. The focus is on a volume-regulated anion conductance (VRAC), which is a member of a ubiquitous family of mechanosensitive ion channels. This conductance is found in a wide variety of cell types and has been implicated in the recovery from cell swelling in many cells, including lymphocytes, the model system used in these studies. This proposal addresses several hypotheses directed toward understanding the regulation of this volume-regulated anion conductance and the contribution of this conductance to cellular volume regulation by concurrent measurements of current amplitude and cell swelling in a hyposmotic environment. Specifically addressed is the hypothesis that volume regulated anion current activity is regulated by the intracellular composition and concentration of osmolytes. Current and volume measurements will be combined with molecular biological techniques to address the hypothesis that the activity of this current is also regulated by a small, cytosolic actin binding protein, termed ICln. Changes in the actin cytoskeleton which provide cells with structure have also been implicated in regulating cell volume and have been suggested as the mechanotransducer which activated the anion current. This hypothesis will be addressed with two proteins, BotC2 and gelsolin to alter the equilibrium between F- and G- actin and determining the effect on current activation and cell swelling using electrophysiological, molecular and fluorescent techniques. Successful completion of this proposal will provide a greater understanding of the underlying mechanisms of mechanotransduction in cells and their role in volume regulation under normal and pathological conditions.