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的细胞运作中起着关键作用。 致病变异与许多神经、心血管和代谢紊乱有关。虽然 一些变体通过改变配基调节或离子渗透而导致KIR中的门控缺陷，存在着越来越多的 有证据表明，许多--也许是大多数--变异导致KIR的折叠和贩运存在缺陷。尽管中央 对于折叠和贩卖作用的疾病病因，迄今还没有全面的大规模研究 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 我们首次对错义和拓扑突变对KIR运输的影响进行了全面评估 和功能。获取这些数据是建立定量的生物物理模型的必要的第一步 KIR中的序列、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，并确定新的KIR治疗策略- 连锁性疾病。这些模型也将为KIR作为化学发生试剂的合理工程铺平道路 这可以用来研究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.