Functional characterization of the dark matter ion channel polycystin2-like2

暗物质离子通道多囊蛋白2-like2的功能表征

• 批准号: 10452157
• 负责人: Markus G Delling
• 金额: $ 16.15万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-07-01 至 2024-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10452157
• 关键词: Area; Bacteria; Biological; Biological Assay; Biological Process; Biology; Cells; Chemicals; Cilia; Complex; Congenital Heart Defects; Cyst; Data; Defect; Development; Disease; Divalent Cations; Drug Targeting; Electrophysiology (science); Endoplasmic Reticulum; Endosomes; Environment; Family; Family member; Fertilization; G-Protein-Coupled Receptors; Genome; Goals; Handedness; Human; Human Genome; Ion Channel; Ions; Kidney; Knowledge; Learning; Length; Light; Liver; Maps; Mediating; Membrane; Memory; Methods; Molecular; Monitor; Monoclonal Antibodies; Mutation; Optics; Organ; Organelles; Output; Pancreas; Pharmaceutical Preparations; Phosphatidylinositol 4,5-Diphosphate; Physiological; Plasma; Process; Protein Isoforms; Protein translocation; Proteins; Regulation; Second Messenger Systems; Signal Transduction; Specificity; TRP channel; Work; apical membrane; base; biophysical properties; body system; ciliopathy; clinically relevant; congenital heart disorder; dark matter; human disease; member; novel; patch clamp; therapeutic target; treatment strategy; voltage

PROJECT SUMMARY Ion channels are multispan transmembrane proteins that transport ~106 to 107 ions per second across membranes. The human genome encodes ~400 different ion channel (1.5% of the genome) that control such diverse processes as fertilization, proliferation, development, learning and memory. Although it is well validated that ion channels are at the core of many diseases, approved drugs are available for only a small percentage of this protein class. A major bottleneck in expanding the palette of ion channels as potential drug targets is the fact that several ion channels are only poorly characterized with respect to their biological function and regulation. Subcellular compartmentalization of ion channels to organellar membranes such as endoplasmic reticulum, endosomes or primary cilia further complicates a detailed biophysical characterization. As a consequence, a significant number of ion channels qualify as dark matter of the human genome with unknown function. One such dark matter ion channel is PKD2-L2, one of three members of the polycystin channel family. Mutations in the other polycystin members cause a plethora of human diseases, ranging from congenital heart disease and laterality defects to cyst formation in multiple organs (liver, kidney and pancreas). Polycystin channels are enriched in primary cilia, antenna-shaped protrusions of the apical membrane but the molecular mechanisms by which polycystin channels are regulated and thus contribute to ciliary signaling remains poorly understood. The central goal of this project is to functionally characterize PKD2-L2 containing polycystin channels and determine how PKD2-L2 contributes to ciliary signaling. There are two specific aims. The first aim characterizes the biophysical properties of homomeric and heteromeric polycystin channels containing PKD2-L2. The second aim is to determine the subcellular localization of homomeric and heteromeric PKD2-L2 channels. The applicants’ preliminary observations include several novel unpublished methods. Completion of this project will be a critical step towards understanding the fundamental principles of ion channel signaling within primary cilia. Our long‐ term goal is to understand how dysregulation of ciliary ion channels cause human ciliopathies and establish PKD2-L2 as a therapeutic target.

项目摘要 离子通道是多跨跨膜蛋白，每秒运输约106至107个离子 膜。人类基因组编码约400个不同的离子通道（基因组的1.5％） 潜水过程作为受精，增殖，发展，学习和记忆。尽管已得到充分验证 离子渠道是许多疾病的核心，只有一小部分的批准药物可用 这个蛋白质类。扩展离子通道调色板作为潜在药物靶标的主要瓶颈是 几个离子通道仅在其生物学功能和调节方面的特征很差。 离子通道的亚细胞隔室化到有机膜，例如内质网， 内体或原发性纤毛进一步使详细的生物物理表征复杂化。结果， 大量的离子通道作为人类基因组的暗物质，具有未知功能。一个这样的 暗物质离子通道是PKD2-L2，这是Polycystin通道家族的三个成员之一。突变 其他多囊成员会引起大量人类疾病，从先天性心脏病和 多个器官（肝，肾脏和胰腺）中的侧向缺陷。多囊通道是 富含根尖膜的原代纤毛，天线形蛋白，但分子机制 哪些多囊蛋白通道受到调节，因此有助于纤毛信号传导仍然很少理解。这 该项目的中心目标是在功能上表征包含多囊蛋白通道的PKD2-L2并确定 PKD2-L2如何有助于睫状信号传导。有两个具体的目标。第一个目的是 含有PKD2-L2的同源物和异源多囊通道的生物物理特性。第二个目标 是为了确定同源物和杂体PKD2-L2通道的亚细胞定位。申请人的 初步观察包括几种新型未发表的方法。该项目的完成将是关键 迈向理解原发性纤毛内离子通道信号传导的基本原理。我们的长期 术语目标是了解睫状离子通道的失调如何引起人类纤毛病并建立 PKD2-L2作为治疗靶标。