Chemical probes of the astroglial potassium channel Kir4.1

描述（由申请人提供）：内向整流钾（Kir）通道是多种生理过程的关键调节因子，可能是疾病的新药物靶点。然而，在大多数情况下，缺乏选择性药理学探针阻碍了确定其特定细胞功能以及其药物性和治疗潜力的进展。在这里，研究人员建议开发强大的初级和次级分析，以支持针对“星形胶质”内向整流通道Kir4.1的探针开发工作。该通道主要在神经系统、内耳和肾小管的胶质细胞中表达，可能是胶质细胞癌、髓鞘形成障碍和高血压的药物靶点。在目标1中，研究人员将开发基于荧光的Kir4.1通道功能铊（Tl+）通量测定，用于384孔板或1536孔板的高通量筛选（HTS）。该试验将通过对约3000个小分子Kir4.1活性调节剂进行筛选来验证HTS。在目标2中，研究人员将开发额外的高通量Tl+通量和中等通量电生理分析，以支持他们随后的探针开发活动。概要：这项工作的长期目标是开发新的化学工具来探测神经系统和肾脏中表达的“钾通道”的结构、功能和治疗潜力。这些研究可能为开发治疗癌症、运动障碍和高血压的新药奠定基础。

DESCRIPTION (provided by applicant): Inward rectifying potassium (Kir) channels are key regulators of diverse physiological processes and may represent novel drug targets for diseases. In most cases, however, the lack of selective pharmacological probes has hindered progress toward defining their specific cellular functions as well as their drugability and therapeutic potential. Here the investigators propose to develop robust primary and secondary assays to support probe development efforts directed toward the "astroglial" inward rectifier channel Kir4.1. This channel is expressed predominately in glial cells of the nervous system, inner ear and kidney tubule and may be a drug target for glial-cell cancers, disorders of myelination and hypertension. In Aim 1, the investigators will develop a fluorescence-based thallium (Tl+) flux assay of Kir4.1 channel function for high-throughput screening (HTS) in either 384- or 1536- well plates. The assay will be validated for HTS by performing a screen of approximately 3,000 small molecules for modulators of Kir4.1 activity. In Aim 2, the investigators will develop additional high- throughput Tl+ flux and moderate-throughput electrophysiological assays to support their subsequent probe development campaign. Lay summary: The long-term objective of this work is to develop novel chemical tools which to probe the structure, function and therapeutic potential of a "potassium channel" expressed in the nervous system and kidney. These studies may lay the foundation for the development of novel drugs to treat cancer, movement disorders and high blood pressure. PUBLIC HEALTH RELEVANCE: Inward rectifying potassium (Kir) channels play key physiological roles in diverse cell types and may represent novel therapeutic targets. However, the lack of selective small-molecule probes has hindered efforts to understand the integrative physiology and pharmacology of most Kir channels. Here we propose to develop robust fluorescence and electrophysiological assays to support high-throughput screening (HTS) and probe development efforts directed toward the "astroglial" potassium channel Kir4.1.