Discovery and mechanism of BK channel gating modulators

项目摘要 大电导钙激活钾通道（SLO-1或BK通道）在钙激活钾通道中起关键作用。 在限制平滑肌收缩性和神经元兴奋性中的生理作用。删除BK 在基因靶向动物模型中，通道孔形成（α）或调节（β）亚基可以 导致动脉高血压、膀胱和勃起功能障碍等疾病， 神经系统疾病，包括癫痫;人类BK通道亚基的突变与 全身性癫痫伴阵发性运动障碍（GEPD）、哮喘和自闭症谱系 紊乱因此，BK通道激活剂可以成为治疗方案的组成部分， 心血管和/或神经系统疾病。利用BK通道作为潜在的医疗 因此，重要的是要扩大我们的BK通道激活剂的分子库， 他们的行动机制。这样做将导致在理解BK的整体努力中取得进展 通道门控机制，并最终找到新的治疗心血管和 神经系统疾病根据这一建议，我们将通过以下方式实现这些目标： 1)基于细胞的荧光筛选，其目的是发现用于 BK通道由组织特异性亚基组合组成，和2）系统性 电生理实验以确定这些药物是否调节BK通道 通过与Ca 2+传感器、电压传感器或细胞膜的孔结构域的相互作用发挥功能。 频道 该设备补充将用于购买等温滴定量热计 (ITC)能够直接测定药物-受体的热力学结合常数， 交互.这个工具将大大增强我们的研究，以产生对BK的基本见解 通道门控机制，可能进一步导致新的治疗疾病。

PROJECT SUMMARY Large conductance calcium-activated K channels (SLO-1 or BK channels) play a key physiological role in limiting smooth muscle contractility and neuronal excitability. Deletion of BK channel pore-forming (alpha) or modulatory (beta) subunits in gene-targeted animal models can lead to diseases that include arterial hypertension, bladder and erectile dysfunction, and neurological disorders including epilepsy; mutations in human BK channel subunits are linked to generalized epilepsy with paroxysmal dyskinesia (GEPD), asthma, and autism spectrum disorders. BK channel activators could thus become components of treatment regimens for cardiovascular and/or neurological disease. To exploit BK channels as a potential medical target, it will be important to expand our molecular arsenal of BK channel activators and learn their mechanisms of action. Doing so will lead to advances in an overall effort to understand BK channel gating mechanisms and ultimately find new treatments for cardiovascular and neurological disease. Under this proposal, we will achieve these goals through a combination of 1) cell-based fluorescent screening, which is aimed at discovery of novel gating modulators for BK channels comprised of tissue-specific subunit combinations, and 2) systematic electrophysiological experiments to determine whether these drugs modulate BK channel function through interactions with the Ca2+-sensor, voltage-sensor, or pore domains of the channel. This equipment supplement will be used for purchase of an isothermal titration calorimeter (ITC) that is capable of directly determining thermodynamic binding constants in drug-receptor interactions. This tool will greatly enhance our research to yield fundamental insights toward BK channel gating mechanisms that may further lead to new treatments for disease.