Integrating Drosophila and human podocyte studies to discover APOL1 renal toxicity mechanism and therapeutic targets

非洲裔美国人患肾脏疾病的风险增加，这在很大程度上是由于APOL1风险等位基因的遗传 (RA)。APOL1肾病的分子和细胞机制正在被广泛研究， 但其机制仍不清楚，潜在的治疗靶点仍未被发现。我们产生了一只果蝇 研究APOL1肾病的模型和显示APOL1-RA导致肾细胞损伤的昆虫 人类足细胞的结构和功能同源物。最近开发的小鼠APOL1模型提供了 是研究APOL1肾病分子机制和测试有希望的治疗方法的关键工具，但它 不能用于进行大规模的基因筛选，以确定可能对抗肾脏的修饰基因 APOL1-RA的毒性。使用鼠标模型来筛选数百名候选人也是极其困难的 药物化合物。果蝇系统在低成本和高效率方面表现出独特的优势， 使其成为修饰基因筛选的理想模型，以确定新的APOL1-RA相互作用因子 抢救APOL1肾毒性，或检测从细胞APOL1药物中鉴定出的数百种药物化合物 屏幕。我们提出以下三个目标来开发果蝇在APOL1上的这些独特优势 肾病研究：目的1利用RNA-Seq和跨物种鉴定APOL1-RA下游基因 用果蝇肾细胞和人足细胞进行比较，并测试它们作为潜在的治疗靶点； 目的2、利用果蝇遗传筛选技术筛选APOL1肾毒性调节基因，并对其进行验证。 肾细胞和人足细胞的潜在治疗靶点；目标3，使用果蝇作为药物筛选 从基于细胞的APOL1药物筛查中筛选阳性匹配的平台。实现上述提出的目标 将产生新的、突破性的发现，以了解APOL1肾病的分子机制。我们 将识别下游的APOL1-RA靶基因，利用果蝇基因识别潜在的治疗靶点 筛选加上人体足细胞验证，筛选出最有效和毒性最低的药物化合物 可能最终用于治疗APOL1肾病。

African Americans face elevated risk of kidney disease, due in large part to inheritance of APOL1 risk alleles (RA). The molecular and cellular mechanisms underlying APOL1 nephropathy are being extensively investigated, but the mechanism remains unclear and potential therapeutic targets remain hidden. We generated a Drosophila model to study APOL1 nephropathy and showed that APOL1-RA led to renal cell injury in nephrocytes, the insect structural and functional homologs of human podocytes. The recently developed mouse APOL1 model provides a critical tool to study the molecular mechanism of APOL1 nephropathy and to test promising treatments, but it cannot be used to conduct large-scale genetic screens to identify modifier genes that could antagonize the renal toxicity of APOL1-RA. It is also extremely difficult to use the mouse model to screen for hundreds of candidate drug compounds. The Drosophila system presents unique advantages in terms of low-cost and high-efficiency, making it an ideal model for modifier genetic screening to identify novel APOL1-RA interacting factors that could rescue APOL1 renal toxicity, or to test hundreds of drug compunds identified from cell-based APOL1 drug screens. We propose the following three aims to exploit these unique advantages of Drosophila for APOL1 nephropathy studies: Aim 1, Identify downstream genes of APOL1-RA using RNA-Seq and cross-species comparison, and test them as potential therapeutic targets using Drosophila nephrocytes and human podocytes; Aim 2, Identify modifier genes for APOL1 renal toxicity using Drosophila genetic screening, and test them as potential therapeutic targets in nephrocytes and human podocytes; Aim 3, Use Drosophila as a drug screening platform to screen positive hits from a cell-based APOL1 drug screen. Accomplishing the above proposed aims will yield novel, ground-breaking discoveries to understand molecular mechanisms of APOL1 nephropathy. We will identify down-stream APOL1-RA target genes, identify potential therapeutic targets using Drosophila genetic screening plus human podocyte validation and screen the most effective and least toxic drug compounds that may eventually be used to treat APOL1 nephropathy.