Increasing the Complexity of Microtubule-based transport: Cargo adaptors and Hitchhiking on Vesicles.

增加基于微管的运输的复杂性：货物适配器和囊泡搭便车。

• 批准号: 10713449
• 负责人: JOHN SALOGIANNIS
• 金额: $ 39万
• 依托单位: UNIVERSITY OF VERMONT & ST AGRIC COLLEGE
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-22 至 2028-08-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10713449
• 关键词: Adaptor Signaling Protein; Address; Affect; Binding; Biochemistry; Biological Models; Cell physiology; Defect; Development; Disease; Dynein ATPase; Eukaryotic Cell; Genetic; Goals; Growth; Kinesin; LRRK2 gene; Link; Membrane; Microscopy; Microtubules; Molecular; Molecular Motors; Motor; Movement; Mutation; Neurodegenerative Disorders; Neurodevelopmental Disorder; Organelles; Parkinson Disease; Phosphorylation Site; Phosphotransferases; Play; Positioning Attribute; Research; Role; Site; Specificity; Vesicle; age related; cell growth; macromolecule; malignant neurologic neoplasms; nervous system disorder; organelle movement; rab GTP-Binding Proteins; recruit; trafficking

PROJECT SUMMARY Proper positioning of intracellular cargos (organelles, vesicles, and macromolecules) is critical for cell growth, maturation, and survival. Eukaryotic cells use the molecular motors dynein and kinesin to transport cargos along microtubule tracks. Defects in microtubule-based transport and mutations in the motors themselves, are an underlying feature of many neurodevelopmental and neurodegenerative diseases. Since each type of cargo is tuned for specific cellular functions, their loading, movement and unloading along microtubules requires divergent transport mechanisms. How is cargo specificity on microtubules achieved? This proposal will address this with an in-depth analysis of the two major modes of microtubule-based transport. The canonical view, known as the cargo adaptor mode, is that each cargo interacts with specific adaptor proteins capable of recruiting molecular motors. The regulatory mechanisms by which cargos selectively load and unload from these cargo adaptors are not well understood. One goal of this proposal is to determine how a conserved phosphorylation site on vesicle-bound Rab GTPases affects interactions with dynein cargo adaptors and ultimately, how these interactions affect cellular function. Importantly, this Rab phosphorylation site is the predominant target of the Parkinson’s disease-linked kinase LRRK2. The other mode of transport is called organelle hitchhiking. In hitchhiking, Rab-vesicles can direct the movement of organelles on microtubules. To accomplish this, organelles attach to (or ‘hitchhike’ on) motor-driven Rab-vesicles at membrane contact sites. Organelle hitchhiking is a new, relatively unexplored paradigm of microtubule-based transport, and the underlying molecular mechanisms are not well understood. What are the molecular linkers, tethers, and regulators of organelle hitchhiking? Is this a prominent mode of microtubule-based transport? This proposal will use genetics, microscopy, and biochemistry in both fungal and mammalian model systems to address these questions. Taken together, studying the two main modes of microtubule-based transport is extremely important, given the critical roles Rabs, vesicles, and hitchhiking cargos play in development and age-related diseases.

项目摘要 适当定位细胞内的碳（细胞器，蔬菜和大分子）对于细胞生长至关重要， 物质和生存。真核细胞使用分子电机动力蛋白和驱动蛋白沿 微管轨道。电动机本身中基于微管的运输和突变的缺陷是一种 许多神经发育和神经退行性疾病的基本特征。由于每种类型的货物是 调谐针对特定的细胞功能，其负载，移动和沿微管的卸载需要 发散的运输机制。如何实现微管的货物特异性？该建议将解决 这是对基于微管的两种主要模式的深入分析。典型的观点，已知 作为货物适配器模式，每个货物都与能够招募的特定适配器蛋白相互作用 分子电动机。从这些货物中选择性加载并卸载货物的监管机制 适配器不太了解。该建议的目标之一是确定如何保守的磷酸化 在囊泡结合的Rab GTPase上的位置会影响与动力蛋白货物适配器的相互作用，最终如何 相互作用会影响细胞功能。重要的是，这个Rab磷酸化位点是 帕金森氏病的激酶LRRK2。另一种运输方式称为Organelle搭便车。在 搭便车，兔子可以指导细胞器在微管上的运动。为了实现这一目标， 附着在膜接触部位（或膜驱动的Rab-vesicles）附加到膜接触地点。 Organelle Hitchhiking是一个新的， 基于微管的转运和潜在的分子机制的相关意外范式是 不太了解。有机器搭便车的分子接头，系和调节剂是什么？这是吗？ 基于微管运输的突出模式？该建议将使用遗传学，显微镜和生物化学 在真菌和哺乳动物模型系统中都可以解决这些问题。两者一起研究两个 鉴于兔子，蔬菜和关键作用，基于微管运输的主要模式非常重要 搭便车的嘉戈斯在发育和与年龄有关的疾病中发挥作用。