Caveolae and adipocyte lipid metabolism

小凹和脂肪细胞脂质代谢

基本信息

批准号：
8843840
负责人：
PAUL F PILCH
金额：
$ 40.82万
依托单位：
BOSTON UNIVERSITY MEDICAL CAMPUS
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-07-05 至 2016-04-30
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8843840
关键词：
ANXA2 gene Address Adipocytes Adipose tissue Affect Age Animals Annexins Area Binding Biochemical Biological Assay Biology Blood Glucose Body Weight CAV1 gene Cardiovascular system Caveolae Cell Culture Techniques Cell Line Cell membrane Cell physiology Cell surface Cells Characteristics Cholesterol Cholesterol Homeostasis Communities Complex Cyclodextrins Cytoskeleton Cytosol Data Employee Strikes Event Excision Familial generalized lipodystrophy Family Fasting Fatty Acids Fatty acid glycerol esters Functional disorder Genes Goals Health Hormonal Hormones Human Human Biology Impairment In Vitro Insulin Insulin Resistance Integral Membrane Protein Isoproterenol Knock-out Knockout Mice Lipids Lipodystrophy Lipolysis Liposomes Mass Spectrum Analysis Membrane Membrane Proteins Metabolic Metabolism Modeling Molecular Monitor Mus Mutation Myocardium Organ Organism Pathology Pathway interactions Peripheral Phenotype Phosphorylation Physiological Physiology Population Protein Isoforms Proteins Proteome Protocols documentation Recovery Regulation Research Role Scaffolding Protein Sphingolipids Structure System Testing Time Tissues Ubiquitination Western Blotting Work caveolin 1 cell type feeding glucose tolerance human disease in vivo inhibitor/antagonist interest lipid metabolism male multicatalytic endopeptidase complex novel perilipin response small hairpin RNA sterol esterase

项目摘要

DESCRIPTION (provided by applicant): Caveolae and adipocyte lipid metabolism Caveolae are prominent features of the adipocyte plasma membrane comprising ca. 50% of the cell surface area, thus begging the question of why they are so abundant and what their functions are in this metabolically important cell type. Caveolar structures are 50-100 nm sac-like invaginations projecting from the plasma membrane into the cytosol. They are comprised of small integral membrane proteins, caveolins 1 & 2, and peripheral membrane proteins of the cavin family (cavin-1- 3). They concentrate high levels of cholesterol and sphingolipids which are needed to maintain their structural integrity. Loss of adipocyte caveolae components, in vitro and in vivo, by gene manipulation/inactivation results in abnormalities of adipocyte metabolism. It is the long-term goal of this proposal to understand how the relevant proteins and lipids interact to form caveolae, and how caveolae impact the metabolic and biochemical functions of the fat cell, which has phenotypic consequences for the organism. Specific Aim 1 will address the mechanism(s) by which lipid metabolism is dysregulated in vitro and in vivo in adipocytes deficient in caveolae. Preliminary data support the hypothesis that cavin-1 and/or cavin-2 serve as regulatory factor(s) in hormonally- stimulated lipolysis, and we will experimentally address this hypothesis in animals and in cell culture models lacking specific caveolae components. Cholesterol depletion collapses caveolae concomitantly with remodeling of the cortical cytoskeleton and degradation of cavin-2 by the proteosome. In Aim 2, we will manipulate caveolae by this and other protocols to determine how caveolae sense cholesterol, and how caveolae influence plasma membrane organization and function. We will test the hypothesis that ubiquitination is requisite for caveolae formation. In Aim 3, we propose to phenotypically analyze mice lacking cavin-1 in adipocytes to assess the contribution of this tissue to the metabolic abnormalities seen in the global cavin-1 knockout, and we will metabolically characterize mice lacking cavin-3, which have a reduced adipose mass. We will also phenotype and analyze cavin-2 knockout mice. The multi-organ phenotype of caveolae-deficient mice appears identical to that of humans harboring inactivating mutations in caveolae components, and therefore the physiological relevance of these studies to human biology is considerable. The adipocyte studies will also inform the research community interested in caveolae in other relevant systems and tissues, for example, in cardiovascular biology.

描述（由申请人提供）：小窝和脂肪细胞脂质代谢小窝是脂肪细胞质膜的突出特征，包括Ca。细胞表面积的50％，因此乞求了为什么它们如此丰富的问题以及它们在这种代谢上重要的细胞类型中的功能。洞穴结构是从质膜投射到细胞质的50-100 nm类似SAC样的内陷。它们由小的整合性膜蛋白，小窝蛋白1和2以及卡文家族的周围膜蛋白（Cavin-1-3）组成。他们集中了高水平的胆固醇和鞘脂，以维持其结构完整性。通过基因操纵/失活的体外和体内脂肪细胞小窝成分的损失导致脂肪细胞代谢异常。该提案的长期目标是了解相关蛋白和脂质如何相互作用以形成小窝，而小窝如何影响脂肪细胞的代谢和生化功能，这对生物体具有表型后果。具体目标1将解决脂质代谢在体外和体内失调的机制，而在小窝中缺乏脂肪细胞中的体内。初步数据支持以下假设：Cavin-1和/或Cavin-2是荷尔蒙刺激脂解的调节因子，我们将在动物和缺乏特定洞穴成分的细胞培养模型中实验地解决这一假设。胆固醇的耗竭使小窝与蛋白质体的皮质细胞骨架和Cavin-2降解相同。在AIM 2中，我们将通过该方案和其他方案来操纵口腔，以确定小窝感觉胆固醇的感觉，以及小窝如何影响质膜的组织和功能。我们将检验以下假设：泛素化是小窝形成所必需的。在AIM 3中，我们建议表型分析脂肪细胞中缺乏Cavin-1的小鼠，以评估该组织对全球Cavin-1敲除中代谢异常的贡献，我们将代谢缺少Cavin-3的小鼠，这些小鼠缺乏Cavin-3，这些小鼠的脂肪量减少了。我们还将表型和分析Cavin-2基因敲除小鼠。小鼠缺陷小鼠的多器官表型似乎与在小窝成分中无效突变的人类相同，因此这些研究与人类生物学的生理相关性是相当可观的。脂肪细胞研究还将告知对其他相关系统和组织中的小窝感兴趣的研究界，例如心血管生物学。