Caveolae and adipocyte lipid metabolism

小凹和脂肪细胞脂质代谢

• 批准号: 9265472
• 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
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-07-05 至 2018-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9265472
• 关键词: 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 model; 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; 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; 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; caveolin-2; cell type; glucose tolerance; human disease; in vivo; inhibitor/antagonist; interest; lipid metabolism; male; metabolic profile; multicatalytic endopeptidase complex; novel; perilipin; public health relevance; response; small hairpin RNA; sterol esterase

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)：小凹和脂肪细胞脂代谢小窝是脂肪细胞质膜的显著特征，约占细胞表面积的50%，因此提出了为什么它们如此丰富以及它们在这一代谢重要的细胞类型中的功能是什么的问题。囊泡结构是50-100 nm的囊状凹陷，从质膜突入胞浆。它们由小的整体膜蛋白、小窝蛋白1和2以及小窝蛋白家族的外周膜蛋白(Cavin-1-3)组成。它们集中了维持其结构完整性所需的高水平的胆固醇和鞘脂。在体外和体内，通过基因操作/失活，脂肪细胞小凹成分的丢失会导致脂肪细胞代谢的异常。这项建议的长期目标是了解相关蛋白质和脂类如何相互作用形成小凹，以及小凹如何影响脂肪细胞的代谢和生化功能，这对有机体具有表型后果。具体目标1将阐述脂肪细胞体内和体外脂肪代谢失调的机制(S)。初步数据支持Cavin-1和/或Cavin-2在激素刺激的脂解中作为调节因子(S)的假设，我们将在动物和缺乏特定小窝成分的细胞培养模型中实验解决这一假设。胆固醇耗竭伴随着皮质细胞骨架的重塑和蛋白小体对Cavin-2的降解而导致小凹的塌陷。在目标2中，我们将通过这个和其他方案来操纵小窝，以确定小窝如何感知胆固醇，以及小窝如何影响质膜组织和功能。我们将检验泛素化是小窝形成所必需的假设。在目标3中，我们建议对脂肪细胞中缺乏Cavin-1的小鼠进行表型分析，以评估该组织对全球Cavin-1基因敲除中出现的代谢异常的贡献，并将从代谢角度描述缺乏Cavin-3的小鼠的脂肪质量减少。我们还将对Cavin-2基因敲除小鼠进行表型和分析。小窝缺陷小鼠的多器官表型似乎与人类的小窝成分存在失活突变相同，因此这些研究与人类生物学有相当大的生理相关性。脂肪细胞研究还将向对其他相关系统和组织中的小凹感兴趣的研究团体提供信息，例如，在心血管生物学中。

项目成果

Interaction of suppressor of cytokine signalling 3 with cavin-1 links SOCS3 function and cavin-1 stability.

• DOI: 10.1038/s41467-017-02585-y
• 发表时间: 2018-01-12
• 期刊: Nature communications
• 影响因子: 16.6
• 作者: Williams JJL;Alotaiq N;Mullen W;Burchmore R;Liu L;Baillie GS;Schaper F;Pilch PF;Palmer TM
• 通讯作者: Palmer TM