Transcriptomic, therapeutic and genetic investigations of sickle cell nephropathy

镰状细胞肾病的转录组学、治疗和遗传学研究

基本信息

批准号：
9334844
负责人：
ALLISON E ASHLEY-KOCH
金额：
$ 23.85万
依托单位：
DUKE UNIVERSITY
依托单位国家：
美国
项目类别：
财政年份：
2016
资助国家：
美国
起止时间：
2016-08-18 至 2019-07-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/9334844
关键词：
APOL1 gene Adult Albuminuria Alleles Angiotensin-Converting Enzyme Inhibitors Architecture Autophagocytosis Biological Assay Biology CRISPR/Cas technology Candidate Disease Gene Cells Chemicals Chloride Channels Chromosomes, Human, Pair 22 Chronic Kidney Failure Clinical Clustered Regularly Interspaced Short Palindromic Repeats Code Complement Complex Conflict (Psychology)Data Dominant-Negative Mutation End stage renal failure Enzyme-Linked Immunosorbent Assay Exhibits FDA approved Family Family health status Fluorescence Functional disorder GC gene Genes Genetic Genetic Transcription Genetic study Healthcare Hereditary Disease Human Investigation Kidney Kidney Diseases Kidney Failure Knowledge Larva Lead Libraries Linkage Disequilibrium Meta-Analysis Methods Modeling Molecular Genetics Monitor Names Other Genetics Outcome Pathogenicity Pathology Pathway interactions Patients Phenotype Physiological Predisposition Proteinuria Renal function Reporting Reproducibility Research Infrastructure Risk Risk Factors Role Series Sickle Cell Sickle Cell Anemia Signal Transduction Stress Susceptibility Gene Testing Therapeutic Therapeutic Intervention Transcript Transgenic Organisms Validation Variant Vascular Endothelial Cell Zebrafish base cell type cellular pathology cohort deep sequencing differential expression effective therapy genetic risk factor genetic variant genome wide association study in vivo in vivo Model loss of function multidisciplinary mutant next generation sequencing novel novel therapeutics podocyte risk variant small molecule spatiotemporal targeted treatment tool transcriptome sequencing transcriptomics translational study

项目摘要

ABSTRACT Sickle cell disease (SCD) is a genetic disorder with profound consequences to families and the health care infrastructure. Notably, SCD can trigger nephropathy leading to end-stage renal disease (ESRD) with poor outcomes and no effective treatment. SCD-dependent susceptibility to ESRD is influenced by genetic factors. We demonstrated previously that MYH9 and APOL1, two loci in close physical proximity on chromosome 22, are independent predictors of proteinuria in SCD. This region, particularly two major risk alleles (named G1 and G2), has been replicated widely in non-SCD nephropathy. However, conflicting studies have suggested that alleles in either APOL1 or MYH9 might contribute to the pathology through an as yet unclear mechanism. Recently, we employed in vivo studies to understand the contribution of this locus to ESRD. We discovered a role for APOL1 in the developing zebrafish kidney and uncovered a complex genetic architecture, wherein the APOL1 G1 risk allele is a functional null while the G2 risk allele exerts a dominant negative effect. Critically, we also found that APOL1 and MYH9 interact genetically, in the context of anemic stress, potentially reconciling diverse observations about the roles of each gene in ESRD. These advances afford us the opportunity to probe key questions in the field, including: the spatiotemporal context involved in the pathology; the underlying cellular mechanisms and pathways that could be targeted for therapeutic intervention; and the extent to which other genetic factors contribute the SCD nephropathy. Equipped with potent, multidisciplinary working tools, including zebrafish mutants that recapitulate an experimentally tractable, physiologically relevant in vivo pathology, we propose three Aims. First, to examine the cellular pathology of the APOL1/MYH9 locus we will investigate the altered transcriptional networks in multiple relevant cell types in our APOL1 zebrafish models. Through this method, we will be able to query both suggested pathways, such as autophagy and altered chloride channel functionality and discover new ones in an unbiased fashion. Second, the absence of mechanistic knowledge in SCD nephropathy has limited therapeutic options. Although angiotensin-converting enzyme inhibitors (ACEi) appear to reduce albuminuria and are used widely, their efficacy in the context of APOL1 and SCD nephropathies remains unproven. We will screen our relevant APOL1 in vivo models for FDA-approved lead therapeutic compounds that could be transitioned rapidly into the clinical arena. Finally, although APOL1 and MYH9 convey critical risk for SCD nephropathy, there is clear evidence for additional genetic risk factors, the identification of which will likely inform pathomechanism. We will leverage our large SCD nephropathy cohort and our in vivo tools to identify additional susceptibility loci and, thus, provide potentially orthogonal entry points into the biology of this phenotype. Taken together, our studies will inform the pathomechanism underpinned by the MYH9/APOL1 locus, identify new drivers for SCD nephropathy and offer an exciting opportunity to identify lead compounds that will have both investigative and therapeutic potential.

抽象的镰状细胞病（SCD）是一种遗传疾病，对家庭和医疗保健产生了深远的影响基础设施。值得注意的是，SCD会触发肾病，导致终末期肾病（ESRD）结果，没有有效的治疗。 SCD依赖性对ESRD的敏感性受遗传因素的影响。我们以前证明了MYH9和APOL1，两个基因座在22号染色体上的物理近端附近，是SCD中蛋白尿的独立预测指标。该区域，尤其是两个主要风险等位基因（命名为G1 和G2），已在非SCD肾病中广泛复制。但是，矛盾的研究表明 APOL1或MYH9中的等位基因可能通过尚未清楚的机制促进病理。最近，我们采用了体内研究来了解该基因座对ESRD的贡献。我们发现了一个 Apol1在发育中的斑马鱼肾脏中的作用，并发现了复杂的遗传结构，其中 APOL1 G1风险等位基因是功能无效的，而G2风险等位基因会产生主要的负面影响。批判性，我们还发现，在贫血压力的背景下，Apol1和MyH9在遗传上相互作用，可能会和解关于每个基因在ESRD中的作用的不同观察结果。这些进步使我们有机会探测该领域的关键问题，包括：病理中涉及的时空环境；基础可以针对治疗干预的细胞机制和途径；以及在多大程度上其他遗传因素会导致SCD肾病。配备有效的多学科工作工具，包括斑马鱼突变体，这些突变体概括了实验性的，生理上相关的体内病理学，我们提出三个目标。首先，要检查apol1/myh9基因座的细胞病理学，我们将研究我们Apol1斑马鱼模型中多种相关细胞类型中的转录网络的变化。通过这种方法，我们将能够查询建议的途径，例如自噬和更改氯化物频道功能并以公正的方式发现新的功能。其次，没有 SCD肾病中的机械知识具有有限的治疗选择。虽然是血管紧张素转换的酶抑制剂（ACEI）似乎减少了蛋白尿，并被广泛使用，其功效在背景下 APOL1和SCD肾病仍然未经证实。我们将筛选相关的apol1在体内模型中可以快速过渡到临床领域的FDA批准的铅治疗化合物。最后，尽管APOL1和MYH9传达了SCD肾病的关键风险，但有明确的证据表明遗传危险因素，其识别可能会为病理机理提供依据。我们将利用我们的大型 SCD肾病队列和我们的体内工具，以识别其他敏感性基因座，从而提供潜在的正交入口指向该表型的生物学。综上所述，我们的研究将告知由MYH9/APOL1基因座支撑的病理机制，确定SCD肾病的新驱动因素并提供一个令人兴奋的机会来识别将具有调查和治疗潜力的铅化合物。