Investigation of the Role of the KCNH Voltage-Gated Potassium Channel Intracellular Domains in Gating

KCNH 电压门控钾通道细胞内结构域在门控中的作用研究

• 批准号: 10728722
• 负责人: Whitney Alexandra Stevens-Sostre
• 金额: $ 1.78万
• 依托单位: UNIVERSITY OF WISCONSIN-MADISON
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-09-01 至 2023-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10728722
• 关键词: Action Potentials; Address; Animal Model; Area; Arrhythmia; Award; Binding; Binding Sites; Biophysics; Brain; C-terminal; Calcium; Calmodulin; Cardiac; Cardiac Death; Collaborations; Complex; Couples; Critical Thinking; Cyclic Nucleotides; Development; Disease; Doctor of Philosophy; Electrodes; Electron Microscope; Electrophysiology (science); Epilepsy; Equity; Ethers; Family; Functional disorder; Future; Future Generations; Genes; Goals; Heart; Human; Hydrophobic Interactions; Hydrophobicity; Image; Investigation; Ion Channel; Journals; Kinetics; Knowledge; Laboratories; Laboratory Research; Learning; Life; Light; Malignant Neoplasms; Maps; Measures; Mediating; Memory; Methods; Molecular; Molecular Machines; Mutation; N-terminal; Nature; Nervous System; Neurologic; Neurological Models; Neurons; Neurosciences; Nucleotides; Oral; Oxidation-Reduction; Oxygen; Pathologic Processes; Pathway Analysis; Pathway interactions; Peer Group; Pharmaceutical Preparations; Phase; Physiological; Physiological Processes; Point Mutation; Positioning Attribute; Postdoctoral Fellow; Potassium Channel; Presynaptic Terminals; Process; Property; Proteins; Publications; Rattus; Research; Research Personnel; Research Project Grants; Role; Schizophrenia; Scientist; Shapes; Site-Directed Mutagenesis; Structure; Synaptic Transmission; Techniques; Testing; Thermodynamics; Training; Ventricular; Voltage-Gated Potassium Channel; Work; Xenopus oocyte; alpha helix; biophysical techniques; diagnostic biomarker; experience; insight; meetings; mutant; nervous system disorder; neuronal excitability; neurotransmitter release; novel; optogenetics; posters; protein protein interaction; sensor; simulation; skills; synaptic function; targeted treatment; therapeutic development; voltage; voltage clamp

PROJECT SUMMARY/ABSTRACT KCNH channels, also known as the Ether-à-go-go (Eag) family, are voltage-gated potassium ion channels that have roles in neuronal excitability and cardiac repolarization. The dysfunction of these ion channels is implicated in a variety of diseases, including cancer, epilepsy, and cardiac arrythmia, making them promising targets for both diagnostic markers and the development of therapeutic drugs. KCNH channels like EAG and human Ether-à-go-go–Related Gene (hERG) possess unique and highly conserved intracellular domains that have evolved to serve unique physiological roles. The N-terminal Per-Arnt-Sim (PAS) domain has diverse functions in nature: they serve as input modules that mediate protein-protein interactions and as redox potential, oxygen, and light sensors. The C-terminal cyclic nucleotide binding homology (CNBh) domain has structural homology to cyclic nucleotide binding (CNB) domains but lack the ability to bind nucleotides. The intracellular PAS and CNBh domains modulate gating in KCNH channels and are known from structural and functional studies to associate in a complex. Several disease-associated mutations are concentrated at the PAS-CNBhD interface, highlighting the physiological importance of their interaction. However, details of how these domains interact to allosterically regulate critical channel functions, such as slow deactivation in hERG and calmodulin (CaM) inhibition in EAG1, are not understood. This proposal seeks to investigate the role of the KCNH channel intracellular domains in gating by combining structural, computational, and electrophysiological approaches. In Aim 1 (PhD Progress), I describe the presence of a hydrophobic interaction among residues in the PAS-cap (residues1-25), the downstream globular PAS (residues 26-135), and the CNBh domain of a neighboring subunit that are critical for slow deactivation in hERG channels. In Aim 2 (F99 Phase), I propose to uncover the allosteric pathways that mediate Ca2+-CaM inhibition of EAG1 currents. Given the importance of KCNH channels in various physiological and pathological processes, we expect our novel findings to have broad implications in neuroscience and beyond. During the F99 Phase, I will continue my thesis work in my advisor's state-of-the art laboratory with the guidance and support of my colleagues and graduate trainee peer group. I will learn cutting-edge techniques and methods of analysis, as well as develop my critical thinking skills to interpret my findings. I will continue engaging in professional development activities, including journal clubs, seminars, and lab meetings. Finally, I will share my scientific findings through publications, and oral and poster presentations at scientific meetings. My long-term goal is to understand the effects of channelopathies within the nervous system. Thus, for the K00 phase, I have identified specific areas, concepts, and techniques I must develop to become a well-rounded researcher and expert in neurological channelopathies. I intend to utilize my expertise to establish a diverse and equitable academic research laboratory to train future generations of scientists.

项目总结/文摘