Comprehensive mapping of trafficking and functional robustness in Inward Rectifier K+ channels for variant pathogenicity prediction and model-guided engineering of chemogenetic reagents

项目摘要 内向整流钾通道（KIR）在神经肌肉和其他组织细胞的运作中起着关键作用。 致病性变异与许多神经系统、心血管和代谢疾病有关。虽然 一些变体通过改变配体调节或离子渗透引起KIR中的门控缺陷， 许多--也许是大多数--变异体导致KIR折叠和运输缺陷的证据。尽管中央 对于折叠和贩运作用的疾病病因，迄今尚无全面的大规模研究 确定KIR运输和功能稳健性的序列和结构决定因素的研究。这里 我们首次全面评估了错义和拓扑突变对KIR转运的影响 和功能获取这些数据是建立生物物理模型的第一步。 序列、结构和功能关系。这些模型将有助于理解 KIR突变表型的基础，预测其致病性，并确定KIR的新治疗策略- 连锁障碍这些模型也将为KIR作为化学发生试剂的合理工程设计铺平道路 可用于研究K+通道在完整组织中的功能作用。

Project Summary Inward Rectifier K+ channels (KIR) play key roles in the operation of cells in neuromuscular and other tissue. Pathogenic variants are linked to numerous neurological, cardiovascular, and metabolic disorders. Although some variants cause gating defects in KIR by altering ligand regulation or ion permeation, there is growing evidence that many –perhaps most– variants cause defects in folding and trafficking of KIR. Despite the central role for folding and trafficking in the disease etiology, there have been to date no comprehensive large-scale studies that determine sequence and structural determinants of KIR trafficking and functional robustness. Here we provide the first comprehensive assessment of missense and topological mutations’ effects on KIR trafficking and function. Acquisition of these data is the required first step to build quantitative biophysical model of the sequence, structure, and function relationship in KIR. These models will be useful to understand the mechanistic basis for KIR mutation phenotypes, to predict their pathogenicity, and to identify new treatment strategies for KIR- linked disorders. These models will also pave the way for rational engineering of KIR as chemogenetic reagents that can be used to study functional roles of K+ channels in intact tissues.