Lipid droplets as sites for protein sequestration

脂滴作为蛋白质隔离位点

• 批准号: 7502162
• 负责人: MICHAEL Andreas WELTE
• 金额: $ 18.06万
• 依托单位: UNIVERSITY OF ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-09-30 至 2010-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7502162
• 关键词: Address; Area; Binding; Biological; Biological Process; Biological Testing; Biology; Cell Nucleus; Cell physiology; Cells; Chromosome Segregation; Co-Immunoprecipitations; Complement; Development; Disease; Drosophila genus; Embryo; Embryonic Development; Eukaryota; Eukaryotic Cell; Fatty acid glycerol esters; Future; Gel; Gene Expression; Goals; Health; Heat Stress Disorders; Histones; Investigation; Lead; Left; Lipids; Literature; Localized; Mammals; Mass Spectrum Analysis; Molecular; Molecular Profiling; Nuclear; Nuclear Import; Numbers; Obesity; Organelles; Perception; Phosphorylation; Physiological; Play; Post-Translational Protein Processing; Proteins; Proteomics; Recruitment Activity; Reporting; Review Literature; Role; Site; Stress; Stress-Induced Protein; Testing; Time; Work; Yeasts; crosslink; lipid metabolism; mutant; novel; protein folding; protein misfolding; research study; response

DESCRIPTION (provided by applicant): Lipid droplets are intracellular organelles best known for their role in lipid storage and obesity. The goal of this proposal is to determine whether lipid droplets serve a general new function as sites of developmentally regulated protein sequestration. In Drosophila embryos, maternally provided histones appear to be stored on droplets until needed later in development. Various hints in the literature suggest that regulated sequestration - not only of histones but also of other proteins - to lipid droplets is wide spread in eukaryotes from yeast to mammals. Such sequestration could provide a novel mechanism of development, by releasing or inactivating proteins in a temporally or spatially controlled manner. It may also provide a general means by which cells protect themselves from harmful proteins. However, neither the generality nor the mechanisms of sequestration have been established, leaving the function and importance of sequestration unresolved. To determine whether proteins other than histones are sequestered in Drosophila embryos, two strategies will be pursued: it will be determined whether the candidate protein Importin alpha2 is sequestered to droplets in a developmentally regulated manner (by determining its intracellular distribution via immunolocalization and Western analysis of purified fractions) and whether proteotoxic stress induces sequestration of specific proteins (by proteomic analysis of isolated droplets). To uncover mechanisms of sequestration, it will be determined whether sequestered histones and Importin alpha2 carry signature post-translational modifications and which proteins on droplets the histones bind to. These studies will either identify existing mutants that disrupt sequestration or suggest strategies how to generate such mutants, thus leading to a functional test of the biological roles of sequestration, either immediately or in the near future.

描述（由申请人提供）：脂质液滴是细胞内细胞器，以其在脂质储存和肥胖中的作用而闻名。该提案的目的是确定脂质液滴是否作为发育调节蛋白质隔离的位点的一般新功能。在果蝇胚胎中，产妇提供的组蛋白似乎存储在液滴上，直到以后需要开发为止。文献中的各种暗示表明，不仅组蛋白和其他蛋白质的调节隔离 - 脂质液滴在从酵母到哺乳动物的真核生物中广泛传播。这种隔离可以通过时间或空间控制的方式释放或灭活蛋白质来提供新的发育机理。它还可以提供一种一般的手段，细胞可以保护自己免受有害蛋白质的侵害。但是，尚未建立隔离的通用性和机制，从而使隔离的功能和重要性尚未解决。要确定是否将除组蛋白以外的其他蛋白质隔离在果蝇胚胎中，将采用两种策略：将确定是否将候选蛋白的进口素α2隔离为液滴，以发育范围的调节方式（通过通过纯化的蛋白质分析来确定其细胞内分布的特定蛋白质）（是否通过纯化的分布）来确定其特异性分布（是否均分布）。孤立的液滴）。为了揭示隔离的机制，将确定隔离组蛋白和进口α2是否具有翻译后修饰和组蛋白上的蛋白质的蛋白质结合。这些研究将确定破坏隔离的现有突变体，或提出如何产生这种突变体的策略，从而立即或不久的将来对隔离的生物学作用进行功能测试。