ABCA1-mediated biogenesis of nascent HDL particles

ABCA1 介导的新生 HDL 颗粒的生物发生

基本信息

批准号：
8061006
负责人：
Nicholas Lyssenko
金额：
$ 5.51万
依托单位：
CHILDREN'S HOSP OF PHILADELPHIA
依托单位国家：
美国
项目类别：
财政年份：
2011
资助国家：
美国
起止时间：
2011-04-01 至 2014-03-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8061006
关键词：
ATP-Binding Cassette Transporters Amino Acids Apolipoprotein A-I Apolipoproteins Binding Binding Sites Biogenesis Biological Assay Cause of Death Caveolae Cell membrane Cells Chemicals Cholesterol Complex Computer Analysis Coronary heart disease Detergents Development Disease Exhibits Generations Heart Diseases Heterogeneity High Density Lipoprotein Cholesterol High Density Lipoproteins Human Immunoprecipitation Intervention Investigation Knowledge LDL Cholesterol Lipoproteins Lead Length Lipids Liver Longevity Mass Spectrum Analysis Mediating Membrane Microdomains Morbidity - disease rate Mutagenesis Mutation Observational Study Peptides Peripheral Population Process Production Property Proteins Research Risk Signaling Protein Sphingomyelins Surface Plasmon Resonance Testing Therapeutic Intervention Tissues atheroprotective base caveolin 1 cell type crosslink design extracellular feeding heart disease risk mortality novel palmitoylation particle reverse cholesterol transport therapy development

项目摘要

DESCRIPTION (provided by applicant): High-density lipoprotein cholesterol (HDL-c) is an especially promising candidate for therapeutic intervention against coronary heart disease (CHD). Although, absolute levels of HDL-c correlate inversely with the CHD risk, there is growing evidence that cholesterol flux in HDL particles from peripheral tissues to the liver - i.e., reverse cholesterol transport (RCT) - is a more important atheroprotective factor. Recent research shows that different HDL particle species stimulate RCT to varying extents. The origins of particle heterogeneity are unclear. Some particle speciation is already evident in nascent HDL. Nascent HDL is assembled from cellular lipids and extracellular apolipoprotein AI (apoAI) through a process mediated by ATP-binding cassette transporter A1 (ABCA1). In Specific Aim 1, we propose to test the hypothesis that localization of ABCA1 in different microenvironments of the plasma membrane is responsible for nascent HDL particle heterogeneity. Lipid composition of the plasma membrane and putative localization of ABCA1 to different plasma membrane domains will be manipulated to determine what effects these manipulations exert on the nascent HDL population. ApoAI binding protects ABCA1 from degradation and promotes nascent HDL particle formation in a feed-forward regulatory loop. In Specific Aim 2, we propose two primary approaches to identify putative apoAI binding sites on ABCA1. In one approach, ABCA1 and apoAI will be cross-linked and then ABCA1-apoAI complexes will be analyzed using mass spectrometry. In the second approach, computationally selected candidate ABCA1 regions will be chemically synthesized and tested for binding to apoAI using surface plasmon resonance. The regions of ABCA1 identified with the two approaches will be validated using mutagenic analyses and binding completion assays. The knowledge gained from this project will aid in design of novel therapies to stimulate RCT and maximize production of the most atheroprotective HDL species. PUBLIC HEALTH RELEVANCE: Coronary heart disease is a leading cause of death in the US and the world. Present therapies that focus on lowering levels of "bad" (LDL) cholesterol reduce but do not completely eliminate coronary heart disease occurrences. The proposed research should facilitate development of supplemental therapies that exploit heart disease reducing properties of "good" (HDL) cholesterol.

描述（由申请人提供）：高密度脂蛋白胆固醇（HDL-C）是针对冠心病（CHD）治疗干预的特别有前途的候选人。尽管HDL -C的绝对水平与CHD风险成反比，但越来越多的证据表明，HDL颗粒从外周组织到肝脏的胆固醇通量 - 即反向胆固醇转运（RCT） - 是更重要的动脉粥样硬化因子。最近的研究表明，不同的HDL颗粒物种刺激RCT到不同的范围。粒子异质性的起源尚不清楚。在新生的HDL中，一些颗粒形成已经很明显。新生的HDL是通过通过ATP结合盒式转运蛋白A1（ABCA1）介导的过程从细胞脂质和细胞外载脂蛋白AI（APOAI）组装而成的。在特定目标1中，我们建议检验以下假设：ABCA1在质膜不同微环境中的定位是造成新生HDL颗粒异质性的原因。将操纵质膜的脂质组成和ABCA1对不同质膜结构域的推定定位，以确定这些操纵对新生HDL种群的影响。 ApoAI结合可保护ABCA1免受降解，并促进馈送调节环中的新生HDL颗粒形成。在特定目标2中，我们提出了两种主要方法，以识别ABCA1上推定的ApoAI结合位点。在一种方法中，ABCA1和APOAI将交联，然后使用质谱法分析ABCA1-APOAI复合物。在第二种方法中，使用表面等离子体共振的计算选择的候选ABCA1区域将进行化学合成并测试与ApoAI结合。用两种方法识别的ABCA1区域将使用诱变分析和结合完成分析进行验证。从该项目中获得的知识将有助于设计新型疗法，以刺激RCT并最大程度地生产最大的动脉保护HDL物种。公共卫生相关性：冠心病是美国和世界的主要死亡原因。目前专注于降低“不良”（LDL）胆固醇水平的疗法减少但不能完全消除冠心病的发生。拟议的研究应促进开发补充疗法，以利用心脏病降低“良好”（HDL）胆固醇的特性。