Subtype-Specific Small Molecule Chemical Probes for Non-neuronal KCNQ1 Potassium

用于非神经元 KCNQ1 钾的亚型特异性小分子化学探针

• 批准号: 7928000
• 负责人: Meng Wu
• 金额: $ 4.1万
• 依托单位: JOHNS HOPKINS UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-04-23 至 2012-02-29
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7928000
• 关键词: Action Potentials; Arrhythmia; Atrial Fibrillation; Biological Assay; Cardiac; Cardiology; Cell Line; Cell physiology; Cells; Cellular Membrane; Chemicals; Chemosensitization; Collaborations; Complex; Cyclic AMP; Cystic Fibrosis; Development; Diarrhea; Disease; Ear; Epithelial; Epithelial Cells; Etiology; Family; Family member; Fluorescence; Functional disorder; Future; Genus Cola; Hearing; Heart; Heart Arrest; Heart Diseases; Homeostasis; Hormones; Intestines; Investigation; Ion Channel; Ions; Jervell-Lange Nielsen Syndrome; Kidney; Libraries; Long QT Syndrome; Lung; Membrane Proteins; Neurons; Pharmaceutical Chemistry; Pharmacologic Substance; Pharmacology; Play; Potassium; Potassium Channel; Preparation; Role; Romano-Ward Syndrome; Safety; Signal Transduction; Sodium Chloride; Structure; Sudden infant death syndrome; Syndrome; Testing; Thallium; Therapeutic; Tissues; Universities; Validation; Voltage-Gated Potassium Channel; Water; base; hearing impairment; high throughput screening; improved; medical schools; patch clamp; public health relevance; salt balance; scaffold; small molecule; tool

DESCRIPTION (provided by applicant): Ion channels are membrane proteins that selectively conduct ions across cellular membranes, existing in both excitable cells and non-excitable cells. Ion channels play a critical role in cellular physiology, including electrical and cellular signaling, ion homeostasis, and hormone secretion. The objective of this proposal is to find small molecule chemical probes that activate or potentiate a disease-causing potassium channel - KCNQ1. Abnormality of this channel, through co-assembly with other accessory subunits in different tissues, is thought to be causal to both cardiac diseases and epithelial cell diseases, such as long QT syndrome and cystic fibrosis. We have developed cell lines, validated the cell lines in a fluorescence-based thallium surrogate flux assay, and perform feasibility trials of high throughput screening. This proposal outlines a specific plan to conduct a >300,000-compound screen using the KCNQ1 cell line to search for specific activators/potentiators. The active compounds will then be evaluated by automated patch-clamp recording of various cell lines expressing different combinations of KCNQ1/KCNE channels, including KCNE1, KCNE2, KCNE3, KCNE4 and KCNE5 b- subunits. Because different KCNE subunits co-assemble with KCNQ1 in different tissues, specific probes developed from this proposal will therefore be useful for tissue-specific investigations. In collaboration with Dr. Gordon Tomaselli in Division of Cardiology and Dr. Mark Donowitz in Hopkins Center for Epithelial Disorders of Johns Hopkins School of Medicine, our compound validation plan includes testing of the isolated compounds in native preparations. These active compounds, with further efforts in pharmacology and medicinal chemistry, may be exploited for therapeutic remedy of cardiac arrhythmia and water and salt imbalance in epithelial tissues. PUBLIC HEALTH RELEVANCE: Non-neuronal KCNQ1 potassium channels are critical functional components of heartbeat, hearing, and water/salt balance in lung and intestinal tissues. Dysfunction of these potassium channels results in serious arrhythmia, cardiac arrest, hearing loss, diarrhea, and cystic fibrosis. There is increasing evidence for their causality for long QT syndrome, familial atrial fibrillation, Jervell and Lange-Nielsen syndrome, Romano-Ward syndrome, short QT syndrome, and sudden infant death syndrome (SIDS). Discovery of small molecule probes through this project can therefore provide tools for better understanding of these channels, improve assessment of safety concerns in future pharmaceutical development, and develop therapeutics for the above mentioned diseases.

描述（由申请人提供）：离子通道是选择性传导离子穿过细胞膜的膜蛋白，存在于可兴奋细胞和非可兴奋细胞中。离子通道在细胞生理学中起关键作用，包括电和细胞信号传导、离子稳态和激素分泌。该提案的目的是寻找激活或增强致病钾通道-KCNQ 1的小分子化学探针。该通道的异常，通过与不同组织中的其他辅助亚基的共组装，被认为是心脏疾病和上皮细胞疾病如长QT综合征和囊性纤维化的原因。 我们已经开发了细胞系，在基于荧光的铊替代通量测定中验证了细胞系，并进行了高通量筛选的可行性试验。该提案概述了使用KCNQ 1细胞系进行> 300，000化合物筛选以寻找特定激活剂/增强剂的具体计划。然后通过表达KCNQ 1/KCNE通道的不同组合的各种细胞系的自动膜片钳记录来评价活性化合物，所述KCNQ 1/KCNE通道包括KCNE 1、KCNE 2、KCNE 3、KCNE 4和KCNE 5 B-亚基。由于不同的KCNE亚基在不同的组织中与KCNQ 1共组装，因此从该提议开发的特异性探针将用于组织特异性研究。与心脏病科的Gordon Tomaselli博士和约翰霍普金斯医学院霍普金斯上皮疾病中心的Mark Donowitz博士合作，我们的化合物验证计划包括检测天然制剂中分离的化合物。这些活性化合物，随着药理学和药物化学的进一步努力，可能会被开发用于心律失常和上皮组织水盐失衡的治疗。 公共卫生关系：非神经元KCNQ 1钾通道是心脏跳动、听力和肺和肠组织水/盐平衡的关键功能成分。这些钾通道的功能障碍导致严重的心律失常、心脏骤停、听力丧失、腹泻和囊性纤维化。有越来越多的证据表明它们与长QT综合征、家族性房颤、Jervell和Lange-Nielsen综合征、Romano-Ward综合征、短QT综合征和婴儿猝死综合征（SIDS）之间存在因果关系。因此，通过该项目发现小分子探针可以为更好地理解这些通道提供工具，改善未来药物开发中安全性问题的评估，并开发上述疾病的治疗方法。