An HTS to Discover Novel Modulators of the GIRK 2/3 Potassium Channel

用于发现 GIRK 2/3 钾通道新型调制器的 HTS

• 批准号: 8582276
• 负责人: C DAVID WEAVER
• 金额: $ 23.53万
• 依托单位: VANDERBILT UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-15 至 2016-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8582276
• 关键词: Absence of pain sensation; Address; Analgesics; Area; Atrial Fibrillation; Binding Sites; Biological Assay; Brain; Brain region; Cells; Collection; Coupled; Development; Disease; Electrophysiology (science); Epilepsy; Equilibrium; Family; Family member; GIRK1 subunit, G protein-coupled inwardly-rectifying potassium channel; GIRK2 subunit, G protein-coupled inwardly-rectifying potassium channel; GTP-Binding Proteins; Health; Heart Rate; Homo; In Vitro; Investigation; Ion Channel; Knowledge; Lead; Location; Mediating; Midbrain structure; Pain; Pathologic Processes; Pathology; Pattern; Pharmaceutical Chemistry; Physiological; Physiological Processes; Physiology; Potassium; Potassium Channel; Process; Property; Protocols documentation; Research; Research Design; Research Personnel; Rewards; Role; Running; Sampling; Structure; Synapses; Testing; Thallium; Therapeutic; Tissues; Translating; Validation; Ventral Tegmental Area; addiction; base; design; heart rhythm; high throughput screening; in vivo; inhibitor/antagonist; innovation; neurotransmission; novel; scaffold; screening; segregation; small molecule; solute; statistics; success; therapeutic target; tool

Project Summary Ion channels are expressed in every cell in the body and are involved in critical and diverse physiological processes including fast neurotransmission, establishing and maintaining cardiac rhythms, and solute balance. The importance and diversity of ion channel function results both in ion channel-related pathologies but also in a number of ion channel-targeted therapies. Though ion channels have been the targets of intense research over the last three decades, much remains to be understood regarding the roles of specific ion channels in normal physiological processes and disease. A substantial reason for our lack of understanding of the roles of specific ion channels process is the lack of potent and selectively pharmacological tools targeting these channels. The G-protein Coupled Inward Rectifying Potassium K+ Channels (GIRK) are prime examples of an ion channel family that has been the focus of research for nearly two decades and are thought to be potential targets for numerous indications spanning from atrial fibrillation to analgesia. However, there is but one highly potent and selective GIRK inhibitor and no potent and selective GIRK activators. GIRKs are comprised of homo and heteromeric combinations of four subunits (GIRK 1-4). These subunits are expressed in numerous tissues in the CNS and the periphery. Very recently we have used thallium (Tl+) flux- based screening to discover the first potent and selectively activators of a GIRK channel comprised of GIRK1/2 subunits. Surprisingly, none of the ~ 100 GIRK 1/2 activators evaluated thus far show any activity at non-GIRK 1 containing GIRKs (GIRK 2, GIRK 2/3). Thus, we propose to perform a high-throughput screen to discover the first selective activators of the GIRK 2/3 subunit combination. The GIRK 2 and GIRK2/3 subunit combinations have a relatively restricted expression pattern in mid-brain structures such as the ventral tegmental area (VTA) and discrete subcellular localization compared to GIRK 1-containing GIRKs. Though there is building research that implicates these channels in reward and addiction-related circuitry, most of understanding of GIRKs role remains uncertain due to the lack of selective pharmacological tools. Building upon our success in discovering small molecule modulators of GIRK 1/2 using Tl+ flux-based high-throughput screening, we are proposing to screen a 160,000 sample compound collection and characterize hits using a well-developed set of confirmatory, mechanism of action, and selectivity screens designed to identify compounds with the capacity to be developed as subunit-selective GIRK probes. These probes will be immediately useful to begin understanding mechanisms of action and selectivity between GIRK 1 and non-GIRK1 containing GIRKs. These probes will also advance as candidates for in vivo probe development to enable the investigation of GIRK's roles in physiology and exploration of its therapeutic potential for a variety of important indications including addiction, pain, and epilepsy.

项目摘要 离子通道在体内的每个细胞中都表示，并参与关键和多样的生理 包括快速神经传递，建立和维持心律和溶质平衡在内的过程。 离子通道功能的重要性和多样性既导致离子通道相关的病理，又在 许多以离子通道为目标的疗法。尽管离子渠道一直是激烈研究的目标 在过去的三十年中，关于特定离子渠道在 正常的生理过程和疾病。我们缺乏了解角色的重要原因 特定的离子渠道过程缺乏针对这些的有效和有选择的药理工具 频道。 G蛋白耦合向内整流钾K+通道（GIRK）是一个主要例子 离子频道家族已经成为研究的重点近二十年，被认为是潜在的 从房颤到镇痛的许多迹象的目标。但是，只有一个 有效和选择性的girk抑制剂，没有有效的和选择性的侧重激活剂。 Girks由四个亚基（Girk 1-4）的同型和异类组合组成。这些亚基是 在中枢神经系统和外围的许多组织中表达。最近，我们使用了thallium（tl+）通量 - 基于筛选以发现由GIRK1/2组成的GIRK通道的第一个有效激活因子 亚基。令人惊讶的是，迄今为止评估的〜100 GIRK 1/2激活剂都没有显示非girk的任何活性 1包含girk（Girk 2，Girk 2/3）。因此，我们建议执行高通量屏幕以发现 GIRK 2/3亚基组合的第一个选择性激活剂。 Girk 2和Girk2/3亚基组合 在中脑结构（例如腹侧对段区域（VTA））中具有相对受限的表达模式 与1个含Girk 1的Girks相比，离散的亚细胞定位。尽管有建筑研究 这意味着这些渠道是奖励和成瘾相关的电路，大多数对Girks角色的理解 由于缺乏选择性的药理学工具，仍然不确定。基于我们在发现的成功之后 使用基于TL+通量的高通量筛选的GIRK 1/2的小分子调节剂，我们提议 使用一组完善 确认性，作用机理和选择性筛选，旨在识别具有能力的化合物 作为亚基选择性的GIRK探针开发。这些探针将立即开始 理解围绕少女的作用和选择性的作用机制和选择性。这些 探针也将作为候选体内探测器开发的候选者，以使Girk的调查调查 生理学和探索其治疗潜力的作用 成瘾，疼痛和癫痫病。