Molecular basis of fatty acid transport by peroxisomal ABC transporters

过氧化物酶体 ABC 转运蛋白转运脂肪酸的分子基础

• 批准号: 10796495
• 负责人: Amer Alam
• 金额: $ 17.5万
• 依托单位: UNIVERSITY OF MINNESOTA
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2026-07-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10796495
• 关键词: ACBD3 gene; ATP-Binding Cassette Transporters; Acceleration; Adrenoleukodystrophy; Bile Acid Biosynthesis Pathway; Bile Acids; Biochemical; Biological; Cells; Chemicals; Cryoelectron Microscopy; Defect; Development; Diagnostic; Disease; Disease Pathway; Electron Spin Resonance Spectroscopy; Environment; Family; Fatty Acids; Functional disorder; Future; Impairment; In Vitro; Lipids; Liver diseases; Metabolic; Metabolic Diseases; Molecular; Molecular Conformation; Mutation; Neurologic; Pathology; Patient-Focused Outcomes; Peroxisomal Disorders; Phospholipids; Physiological; Property; Regulation; Resolution; Role; Structure; Substrate Specificity; Therapeutic; Very Long Chain Fatty Acid; Work; branched chain fatty acid; combat; design; drug development; fatty acid metabolism; fatty acid transport; functional disability; improved; in silico; in vitro Assay; insight; leukodystrophy; nervous system disorder; peroxisome; rare genetic disorder; stem; tool

Project Summary Peroxisomal ABC transporters like ABCD1, ABCD2, and ABCD3 shuttle very long chain fatty acids (VLCFAs), branched chain fatty acids (BCFAs), and bile acid precursors into peroxisomes. Their functional impairment leads to severe neurological and metabolic pathologies stemming from disrupted phospholipid and fatty acid metabolism, including X-linked Adrenoleukodystrophy (X-ALD), both the most common leukodystrophy and most common peroxisomal disorder that is caused by mutations in ABCD1 and for which no cure exists, and bile acid synthesis defects and liver disease stemming from impaired ABCD3 function. While additional roles for ABCD transporters in a wider array of disease pathways continue to be uncovered, the underlying mechanisms governing their substrate recognition, transport, and transport regulation remain poorly understood. The long- term objectives of this project are to gain insight into peroxisomal ABCD transporter function and regulation in molecular detail. We will use a combination of biochemical and cell biological tools, high resolution structural analysis by cryo-electron microscopy, and continuous wave electron paramagnetic resonance (CW-EPR) spectroscopy to reveal the functionally relevant structural features and conformational states used by ABCD transporters in fatty acid translocation, how they may be altered by ABCD1 mutation in X-ALD, and how ABCD1 is mechanistically distinct from ABCD2 and ABCD3 despite their functional overlap. Specific Aim 1 deals with the development and utilization of in vitro assays for determining substrate specificity profiles and transport properties of ABCD1, ABCD2, and ABCD3. Specific Aim 2 deals with obtaining high resolution structural information of ABCD1, ABCD2, and ABCD3 in functionally relevant states in a physiological lipid environment through cryo-EM analysis. Specific Aim 3 deals obtaining information on the structural dynamics of ABCD1 through CW-EPR studies. Our results will provide fundamental insights into peroxisomal ABC transporter functioning that can be exploited for ABCD1 targeted diagnostic and therapeutic tools to improve X-ALD patient outcomes, provide a framework for the design and development of chemical probes to study ABCD family function, and generate reliable in vitro and in silico tools to accelerate drug development/discovery efforts targeting them.

项目摘要 过氧化物酶体ABC转运蛋白如ABCD 1、ABCD 2和ABCD 3穿梭极长链脂肪酸（VLCFA）， 支链脂肪酸（BCFA）和胆汁酸前体转化为过氧化物酶体。他们的功能障碍导致 磷脂和脂肪酸破坏导致的严重神经和代谢疾病 代谢，包括X连锁肾上腺脑白质营养不良（X-ALD），最常见的脑白质营养不良和最常见的脑白质营养不良。 一种常见的过氧化物酶体紊乱，由ABCD 1突变引起，目前尚无治愈方法，胆汁酸 合成缺陷和肝脏疾病源于受损的ABCD 3功能。而ABCD的其他角色 在更广泛的疾病途径中的转运蛋白继续被发现，潜在的机制 控制其底物识别、运输和运输调节的机制仍然知之甚少。很长的- 本项目的长期目标是深入了解过氧化物酶体ABCD转运蛋白的功能和调节， 分子细节我们将结合使用生物化学和细胞生物学工具， 冷冻电子显微镜和连续波电子顺磁共振（CW-EPR）分析 光谱，以揭示ABCD使用的功能相关的结构特征和构象状态 脂肪酸转运中的转运蛋白，它们如何被X-ALD中的ABCD 1突变改变，以及ABCD 1如何 尽管ABCD 2和ABCD 3的功能重叠，但在机制上与ABCD 2和ABCD 3不同。具体目标1涉及 开发和利用体外试验确定底物特异性和转运 ABCD 1、ABCD 2和ABCD 3的特性。具体目标2涉及获得高分辨率结构 生理脂质环境中功能相关状态下ABCD 1、ABCD 2和ABCD 3的信息 通过冷冻电镜分析具体目标3涉及获得ABCD 1结构动力学的信息 通过CW-EPR研究。我们的研究结果将提供基本的见解过氧化物酶体ABC转运 功能，可用于ABCD 1靶向诊断和治疗工具，以改善X-ALD患者 结果，提供了一个框架的设计和开发的化学探针，研究ABCD家庭 功能，并生成可靠的体外和计算机工具，以加速药物开发/发现工作 瞄准他们。