Motor protein interactions on cytoskeletal networks

细胞骨架网络上的运动蛋白相互作用

• 批准号: 8089322
• 负责人: ADAM G HENDRICKS
• 金额: $ 5.13万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-06-01 至 2012-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8089322
• 关键词: Behavior; Biological Assay; Cell Communication; Charcot-Marie-Tooth Disease; Complement; Complex; Cytoskeleton; Defect; Degenerative Disorder; Development; Dynein ATPase; Endocytosis; Environment; Feedback; Future; Hereditary Spastic Paraplegia; Human; In Vitro; Individual; Intracellular Transport; Kinesin; Length; Link; Melanosomes; Microfilaments; Microtubule-Associated Proteins; Microtubules; Missense Mutation; Motor; Mutation; Myosin Type V; Physiological; Proteins; Regulation; Role; Running; Testing; Time; Vesicle; War; dynactin; genetic regulatory protein; in vitro Assay; in vivo; mathematical model; motor neuron degeneration; public health relevance; research study; trafficking

DESCRIPTION (provided by applicant): Motor proteins operate in a complex environment in the cell where interactions with motors of the same type, oppositely-directed motors, and the cytoskeletal landscape allow long-range, bidirectional transport. Interactions among motor proteins and with the cytoskeleton modulate the behavior of motor proteins in vivo and make possible the targeted trafficking of intracellular cargoes. Motor proteins of different types often associate simultaneously with vesicular cargoes to allow bidirectional transport along microtubules and switching between microtubules and actin filaments. The objective of this study is to elucidate the dynamics of bidirectional transport through analysis of the interactions among motor proteins and with the cytoskeleton in increasingly complex in vitro approximations of the physiological environment. Specifically, we propose the following aims: 1. To investigate the mechanism of interaction between the oppositely-directed motors kinesin and dynein when transporting artificial cargoes. Is bidirectional transport by opposing motors coordinated through regulatory proteins, or the result of a tug-of-war between oppositely-directed motors? How multiple kinesin or dynein do motors function collectively in teams? What role do Microtubule Associated Proteins (MAPs) have in regulating bidirectional transport? 2. To examine bidirectional transport of purified endogenous vesicles and endocytosed cargoes. How does the endogenous complement of motors interact? What influence do the effectors that copurify with the vesicles have on motor function and coordination? 3. To develop a mechanistic, mathematical model of bidirectional transport by kinesin and dynein. A mathematical model will provide a feedback mechanism for the experiments, functioning to test our understanding of bidirectional transport and direct further experiments. What mechanisms of interactions among motors produce results consistent with experimental observations? What future experiments are best suited to further the understanding of bidirectional transport? By systematically increasing the complexity of in vitro assays, we can separate the influence of complicating factors (i.e. motor-motor interactions, cytoskeletal networks, and MAPs) and understand each independently. We can then integrate these individual aspects into more complex assays, sequentially incorporating aspects of the cellular environment. The integrated in vitro experiments and mathematical models will provide an understanding of the dynamics and regulation of intracellular transport, which is critical as defects in intracellular transport are strongly implicated in both developmental and degenerative diseases in humans. PUBLIC HEALTH RELEVANCE: The objective of this study is to elucidate the regulation and dynamics of motor proteins in intracellular transport through analysis of motors in increasingly complex in vitro approximations of the physiological environment. An understanding of intracellular transport is critical as defects are strongly implicated in both developmental and degenerative diseases in humans. For example, a missense mutation in dynactin leads to autosomal dominant motor neuron degeneration and mutations in kinesins have been linked to Charcot-Marie-Tooth Disease Type 2A and Hereditary Spastic Paraplegia.

描述（由申请人提供）：马达蛋白在细胞中的复杂环境中运行，其中与相同类型的马达、相反方向的马达和细胞骨架景观的相互作用允许长距离双向运输。马达蛋白之间以及与细胞骨架之间的相互作用调节马达蛋白在体内的行为，并使细胞内货物的靶向运输成为可能。不同类型的马达蛋白通常同时与囊泡货物结合，以允许沿着微管的双向运输以及在微管和肌动蛋白丝之间的转换。本研究的目的是阐明双向运输的动力学，通过分析马达蛋白之间的相互作用，并在日益复杂的体外生理环境的近似与细胞骨架。具体而言，我们提出以下目标：1.探讨反向运动的驱动蛋白和动力蛋白在运输人工货物时的相互作用机制。双向运输是通过调节蛋白协调的相反马达，还是相反方向马达之间拔河的结果？多个驱动蛋白或动力蛋白如何在团队中共同发挥作用？微管相关蛋白（MAPs）在调节双向转运中起什么作用？2.检查纯化的内源性囊泡和内吞货物的双向转运。内源性的马达互补是如何相互作用的？与囊泡共纯化的效应器对运动功能和协调有什么影响？3.建立驱动蛋白和动力蛋白双向转运的数学模型。数学模型将为实验提供反馈机制，用于测试我们对双向传输的理解并指导进一步的实验。什么样的运动之间的相互作用机制产生的结果与实验观察一致？什么样的未来实验最适合于进一步了解双向传输？通过系统地增加体外试验的复杂性，我们可以分离复杂因素（即运动-运动相互作用，细胞骨架网络和MAP）的影响，并独立地理解每个因素。然后，我们可以将这些单独的方面整合到更复杂的检测中，依次纳入细胞环境的各个方面。集成的体外实验和数学模型将提供对细胞内转运的动力学和调节的理解，这是至关重要的，因为细胞内转运的缺陷强烈地涉及人类的发育和退行性疾病。 公共卫生相关性：本研究的目的是通过分析越来越复杂的体外生理环境中的马达，阐明马达蛋白在细胞内转运中的调节和动力学。细胞内运输的理解是至关重要的，因为缺陷在人类的发育和退行性疾病中都有很大的牵连。例如，dynactin的错义突变导致常染色体显性运动神经元变性，驱动蛋白的突变与Charcot-Marie-Tooth病2A型和遗传性痉挛性截瘫有关。