Abstract：
Mutations in transporters can impact an individual\'s response to drugs and cause many diseases. Few variants in transporters have been evaluated for their functional impact. Here, we combine saturation mutagenesis and multi-phenotypic screening to dissect the impact of 11,213 missense single-amino-acid deletions, and synonymous variants across the 554 residues of OCT1, a key liver xenobiotic transporter. By quantifying in parallel expression and substrate uptake, we find that most variants exert their primary effect on protein abundance, a phenotype not commonly measured alongside function. Using our mutagenesis results combined with structure prediction and molecular dynamic simulations, we develop accurate structure-function models of the entire transport cycle, providing biophysical characterization of all known and possible human OCT1 polymorphisms. This work provides a complete functional map of OCT1 variants along with a framework for integrating functional genomics, biophysical modeling, and human genetics to predict variant effects on disease and drug efficacy.
摘要：
转运蛋白的突变会影响个体对药物的反应并导致许多疾病。已经评估了转运蛋白中的少数变体的功能影响。这里,我们结合饱和诱变和多表型筛选来剖析11,213个错义单氨基酸缺失的影响，以及跨OCT1的554个残基的同义变体，OCT1是一种关键的肝脏异种生物转运蛋白。通过平行表达和底物摄取定量，我们发现大多数变体对蛋白质丰度发挥主要作用，一种通常不与功能一起测量的表型。利用我们的诱变结果，结合结构预测和分子动力学模拟，我们开发了整个运输周期的精确结构-功能模型，提供所有已知和可能的人类OCT1多态性的生物物理表征。这项工作提供了OCT1变体的完整功能图谱以及整合功能基因组学的框架，生物物理建模，和人类遗传学来预测疾病和药物疗效的变异效应。
