MECHANISMS OF ORGANELLE BIOGENESIS AT THE ENDOPLASMIC RETICULUM SUBDOMAINS

内质网亚域细胞器生物发生机制

• 批准号: 10684111
• 负责人: Amit Joshi
• 金额: $ 37.51万
• 依托单位: UNIVERSITY OF TENNESSEE KNOXVILLE
• 依托单位国家: 美国
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-15 至 2027-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10684111
• 关键词: Binding; Biogenesis; C2 Domain; Cell Culture Techniques; Cells; Cellular biology; Defect; Disease; Endoplasmic Reticulum; Eukaryota; Eukaryotic Cell; Family; Fatty Liver; Functional disorder; Goals; Integral Membrane Protein; Intracellular Membranes; Life; Lipids; Lipodystrophy; Mammalian Cell; Medical; Membrane; Metabolic Diseases; Mitochondria; Morphology; Non-Insulin-Dependent Diabetes Mellitus; Nuclear Envelope; Organelles; Play; Proteins; Research; Role; Saccharomyces cerevisiae; Testing; Vesicle; Work; Yeasts; Zellweger Syndrome; fatty liver disease; nervous system disorder; peroxisome; therapeutic target

PROJECT SUMMARY Intracellular membrane-bound organelles are a hallmark of all eukaryotic cells. Understanding how cells generate different organelles remains one of the central problems in cell biology. Some organelles, like the endoplasmic reticulum (ER) and mitochondria, are self-generating whereas other organelles can be generated de novo. The ER plays a central role in organelle biogenesis. Even though the ER is a single continuous membrane that extends from the outer nuclear envelope into the periphery of the cell, there are discrete regions in the ER membrane called ER subdomains. Nascent peroxisomes and lipid droplets (LDs) form at specialized ER subdomains. Remarkably, little is known about these ER subdomains and their role in regulating organelle biogenesis. The goal of our research is to determine the mechanisms of peroxisome and LD biogenesis by detailed characterization of the discrete ER subdomains using S. cerevisiae and mammalian cell culture. Previously, we identified a family of reticulon-like ER membrane tubulating proteins, Pex30 in yeasts and multiple C2 domains containing transmembrane proteins, MCTP1 and MCTP2, in higher eukaryotes. We demonstrated that both Pex30 and MCTPs are localized at discrete ER subdomains where nascent pre-peroxisomal vesicles and LDs are formed. Based on these findings, we proposed to identify the proteins and lipids enriched at the specialized ER subdomains using unbiased as well as candidate-based approaches. We will then test the effects of modulating the functions of candidate proteins and lipids on the formation, abundance, morphology, and distribution of peroxisomes and LDs. Investigating the mechanistic details of peroxisomes and LDs biogenesis from these ER subdomains is not only important for understanding basic principles of cell biology but also has critical medical implications. Several life-threatening neurological disorders including Zellweger syndrome associated with peroxisomal defects and metabolic disorders such as type 2 diabetes and fatty liver disease caused due to LD defects have no cure. Determining the mechanisms of organelle biogenesis will have implications in understanding the pathophysiology of these disorders and provide us hints for potential therapeutic targets.

项目摘要 细胞内膜结合的细胞器是所有真核细胞的标志。了解细胞 产生不同的细胞器仍然是细胞生物学中的核心问题之一。一些细胞器，例如 内质网（ER）和线粒体是自我生成的，而其他细胞器可以是 从头产生。 ER在细胞器生物发生中起着核心作用。即使急诊室是一个 连续膜从外部核包膜延伸到细胞的周围，有 ER膜中的离散区域称为ER子域。新生的过氧化物酶体和脂质液滴（LDS） 在专门的ER子域中形式。值得注意的是，这些子域及其角色知之甚少 在调节细胞器生物发生方面。我们研究的目的是确定过氧化物酶体的机制 和LD生物发生，通过使用酿酒酵母和酿酒酵母对离散ER子域进行详细表征 哺乳动物细胞培养。以前，我们确定了一个类似网状的ER膜管蛋白的家族， 酵母中的PEX30和多个含有跨膜蛋白MCTP1和MCTP2的C2结构域中 较高的真核生物。我们证明了PEX30和MCTP都位于离散的ER子域中 形成了新生的过敏性囊泡和LDS的地方。根据这些发现，我们提出了 使用公正和 基于候选的方法。然后，我们将测试调节候选蛋白功能的效果 以及关于过氧化物酶体和LDS的形成，丰度，形态和分布的脂质。调查 这些ER子域的过氧化物酶体和LDS生物发生的机械细节不仅是 对于理解细胞生物学的基本原理但也具有关键的医学意义。一些 威胁生命的神经系统疾病，包括Zellweger综合征与过氧化物酶体缺陷有关 以及由LD缺陷引起的2型糖尿病和脂肪肝病等代谢疾病没有 治愈。确定细胞器生物发生的机制将对理解 这些疾病的病理生理学，并为我们提供了潜在治疗靶点的提示。