Microtubule Complexes Involved in Intracelluar Transport

参与细胞内运输的微管复合物

• 批准号: 7931513
• 负责人: RONALD D VALE
• 金额: $ 5.69万
• 依托单位: UNIVERSITY OF CALIFORNIA, SAN FRANCISCO
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-30 至 2011-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7931513
• 关键词: ATP Hydrolysis; ATP phosphohydrolase; Actins; Address; Affect; Area; Atomic Resolution X-Ray Crystallography; Binding; Binding Proteins; Biochemical; Biological; Biological Assay; Biological Process; C-terminal; COX7A2L Protein; Cell Death; Cell Polarity; Cell Shape; Cells; Chemotherapy-Oncologic Procedure; Complex; Crystallography; Cytoskeletal Proteins; Cytoskeleton; Destinations; Dimerization; Disease; Drosophila genus; Dynein ATPase; Electron Microscopy; Elements; Environment; Exhibits; Goals; Grant; Homologous Gene; In Vitro; Inflammatory; Interphase; Kinesin; Kinetochores; Life; Malignant Neoplasms; Mediating; Medical; Microscopy; Microtubules; Mitosis; Modeling; Molecular Chaperones; Mothers; Motor; Motor Activity; Movement; Mus; Myosin Type V; Nervous system structure; Neurons; Organelles; Pathway interactions; Play; Plus End of the Microtubule; Positioning Attribute; Property; Proteins; RNA; Recruitment Activity; Regulation; Research; Research Personnel; Role; Saccharomyces cerevisiae; Signaling Molecule; Structure; Surface; System; Techniques; Tertiary Protein Structure; Testing; Tubulin; Well in self; Work; Yeasts; base; cancer cell; cell behavior; cell cortex; cell motility; chemotherapy; dynactin; experience; insight; interest; macromolecule; migration; particle; polymerization; programs; protein complex; protein function; reconstitution; single molecule

DESCRIPTION (provided by applicant): The microtubule cytoskeleton plays an essential role in cell shape, migration, and division. 1 of the major functions of the microtubule cytoskeleton is to facilitate transport of organelle and macromolecules to particular destinations in the cell. Transport can be mediated by 2 strategies. First, ATP hydrolyzing motor proteins can carry cargoes along the surface of the microtubule. Second, certain proteins (+TIP proteins) can selectively track along the growing tip of a microtubule as it extends to the cell cortex and can bind to and deliver certain cargoes (e.g. signaling molecules). Our goals are to understand motor-protein cargo recognition, regulation of motor proteins, and the mechanism by which +TIP interact with microtubule growing ends. In general, we wish to dissect the mechanisms of these proteins using a variety of techniques including x-ray crystallography, electron microscopy, biochemical approaches, in vitro reconstitution assays, and cell biological approaches in living cells. In this grant, we propose the following aims. 1) We wish to determine how a particular subset of mRNAs is selected for transport by motor proteins in yeast. In particular, we wish to solve an atomic structure for a minimal element of such mRNAs complexed with the proteins that are involved in the transport pathway. 2) We have solved crystal structures of several +TIP domains and developed a model suggesting that these proteins function as "polymerization chaperones" that deliver oligomeric tubulin to the growing end of the microtubules. We propose to better define how these proteins interact with tubulin and develop functional assays to garner support for this model. 3) We will study activators of the dynein motor protein, in particular testing the notion that they affect dynein motor activity. We have also identified a new protein that may regulate dynein at kinetochores, and we will pursue further studies of this protein. 4) We will investigate new ATPases that we believe may modulate the dynamics of microtubules. This work has several potential medical applications. First, the +TIP proteins are essential for microtubule function in mitosis and in cell migration, and their selective inhibition may be useful in cancer chemotherapy (by inhibiting the spindle) or in inflammatory disease (by blocking cell migration). Our work on dynein regulators is likely to be important for understanding the spindle checkpoint, a topic of great interest in cancer since modulation of the checkpoint may enhance cancer cell death after chemotherapy.

描述（由申请人提供）：微管细胞骨架在细胞形状、迁移和分裂中起着重要作用。微管细胞骨架的主要功能之一是促进细胞器和大分子运输到细胞中的特定目的地。运输可以通过两种策略来介导。首先，ATP 水解运动蛋白可以沿着微管表面携带货物。其次，某些蛋白质（+TIP 蛋白质）可以选择性地沿着微管的生长尖端延伸到细胞皮层，并可以结合并传递某些货物（例如信号分子）。我们的目标是了解运动蛋白货物识别、运动蛋白的调节以及 +TIP 与微管生长末端相互作用的机制。一般来说，我们希望使用各种技术来剖析这些蛋白质的机制，包括 X 射线晶体学、电子显微镜、生化方法、体外重构测定和活细胞中的细胞生物学方法。在这笔赠款中，我们提出以下目标。 1) 我们希望确定酵母中运动蛋白如何选择特定的 mRNA 子集进行运输。特别是，我们希望解决与参与运输途径的蛋白质复合的此类 mRNA 的最小元素的原子结构。 2）我们已经解决了几个+TIP结构域的晶体结构，并开发了一个模型，表明这些蛋白质充当“聚合伴侣”，将寡聚微管蛋白传递到微管的生长端。我们建议更好地定义这些蛋白质如何与微管蛋白相互作用，并开发功能测定法以获得对该模型的支持。 3）我们将研究动力蛋白运动蛋白的激活剂，特别是测试它们影响动力蛋白运动活动的概念。我们还发现了一种可能调节着丝粒动力蛋白的新蛋白质，我们将对该蛋白质进行进一步的研究。 4) 我们将研究新的 ATP 酶，我们认为它们可以调节微管的动力学。这项工作有几个潜在的医学应用。首先，+TIP 蛋白对于有丝分裂和细胞迁移中的微管功能至关重要，并且它们的选择性抑制可能在癌症化疗（通过抑制纺锤体）或炎症性疾病（通过阻止细胞迁移）中有用。我们在动力蛋白调节剂方面的工作可能对于理解纺锤体检查点很重要，这是癌症中非常有趣的一个话题，因为检查点的调节可能会增强化疗后癌细胞的死亡。