ABCA1-mediated biogenesis of nascent HDL particles

ABCA1 介导的新生 HDL 颗粒的生物发生

• 批准号: 8448765
• 负责人: Nicholas Lyssenko
• 金额: $ 5.77万
• 依托单位: CHILDREN'S HOSP OF PHILADELPHIA
• 依托单位国家: 美国
• 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/8448765
• 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; public health relevance; reverse cholesterol transport; therapy development

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.

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者。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 颗粒中的胆固醇从外周组织流向肝脏（即逆胆固醇转运 (RCT)）是更重要的动脉粥样硬化保护因素。最近的研究表明，不同的 HDL 颗粒种类会不同程度地刺激 RCT。颗粒异质性的起源尚不清楚。在新生的 HDL 中，一些粒子形态已经很明显。新生 HDL 由细胞脂质和细胞外载脂蛋白 AI (apoAI) 通过 ATP 结合盒转运蛋白 A1 (ABCA1) 介导的过程组装而成。在具体目标 1 中，我们建议检验这样的假设：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。质膜的脂质组成和 ABCA1 到不同质膜域的假定定位将被操纵，以确定这些操纵对新生 HDL 群体产生什么影响。 ApoAI 结合可保护 ABCA1 免遭降解，并促进前馈调节环路中新生 HDL 颗粒的形成。在具体目标 2 中，我们提出了两种主要方法来识别 ABCA1 上假定的 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，通过计算选择的候选 ABCA1 区域将被化学合成，并使用表面等离子共振测试与 apoAI 的结合。通过这两种方法鉴定的 ABCA1 区域将使用诱变分析和结合完成测定进行验证。从该项目中获得的知识将有助于设计新疗法，以刺激 RCT 并最大限度地生产最具动脉粥样硬化保护作用的 HDL 物种。

项目成果

Cell lipid metabolism modulators 2-bromopalmitate, D609, monensin, U18666A and probucol shift discoidal HDL formation to the smaller-sized particles: implications for the mechanism of HDL assembly.

细胞脂质代谢调节剂 2-溴棕榈酸酯、D609、莫能菌素、U18666A 和普罗布考将盘状 HDL 形成转变为较小尺寸的颗粒：对 HDL 组装机制的影响。

• DOI: 10.1016/j.bbalip.2016.09.017
• 发表时间: 2016
• 期刊: Biochimica et biophysica acta
• 作者: Quach,Duyen;Vitali,Cecilia;La,FionaM;Xiao,AngelX;Millar,JohnS;Tang,Chongren;Rader,DanielJ;Phillips,MichaelC;Lyssenko,NicholasN
• 通讯作者: Lyssenko,NicholasN