Structure and Function of Cytoplasmic Dynein

细胞质动力蛋白的结构和功能

基本信息

批准号：
7652759
负责人：
Thomas S Hays
金额：
$ 25.72万
依托单位：
UNIVERSITY OF MINNESOTA
依托单位国家：
美国
项目类别：
财政年份：
1990
资助国家：
美国
起止时间：
1990-07-01 至 2011-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/7652759
关键词：
Address Affect Affinity Alanine Alleles Alzheimer&apos s Disease Amyotrophic Lateral Sclerosis Animal Model Aspartate Axon Axonal Transport Binding Biochemical Biochemical Genetics Biological Assay Caenorhabditis elegans Cell Death Cell Differentiation process Cell Line Cells Chromosome Segregation Chromosomes Complement Complex Congenital Abnormality Defect Development Disease Disease model Drosophila genome Drosophila genus Dynein ATPase Excision Exhibits Eye Functional disorder Genes Genetic Goals Growth Human Huntington Disease In Vitro Individual Intracellular Membranes Intracellular Transport Investigation Kinesin Kinetochores Lead Life Light Location Malignant Neoplasms Mediating Medical Membrane Methods Microtubules Mitosis Mitotic Modeling Molecular Molecular Motors Motor Mutate Mutation Nerve Degeneration Neurodegenerative Disorders Neurons Organelles Parkinson Disease Pathogenesis Pathology Pathway interactions Patients Phenotype Phosphorylation Phosphorylation Site Play Post-Translational Protein Processing Preparation Principal Investigator Process Protein Isoforms Proteins Recombinants Regulation Research Research Activity Role Signal Pathway Signal Transduction Site Source Spectrin Spinocerebellar Ataxia Type 5 Structure System Tertiary Protein Structure Testing Therapeutic Time Tissues To specify Transgenes Transport Process Vesicle Work Yeasts adapter protein base cell motility comparative dosage dynactin dynein light chain fly genome wide association study human disease in vivo interest mimetics motor deficit mutant novel overexpression pericentrin polypeptide postsynaptic presynaptic programs protein function public health relevance research study single molecule stable cell line trafficking

项目摘要

DESCRIPTION (provided by applicant): Molecular motor proteins function in a multitude of intracellular transport processes including organelle transport, chromosome segregation, axonal transport, and signaling pathways. Motor dependent processes are critical for growth, proliferation, and the differentiation of cells and tissues. How motor function is regulated in a developmental context, and the relationship of motor dysfunction to numerous medical problems, including neurodegenerative disease and cancer, is a current focus of research activity. Our work is focused on the microtubule motor cytoplasmic dynein, and the important and unanswered questions regarding how this single motor isoform accomplishes multiple tasks. Our aims will address three mechanisms that potentially regulate dynein targeting and/or activity. (1) First, cytoplasmic dynein contains multiple subunits. The individual subunits or subunit domains could specify where, and to what, dynein is attached. Aim 1 includes biochemical and genetic experiments to address how the dynein light chain and light intermediate chain influence dynein functions. (2) Second, the posttranslational modification of dynein subunits might control dynein subunit activities or binding affinities. We are defining the in vivo sites of phosphorylation on dynein subunits and will study the significance of the target sites. The target sites on the LIC subunit will be mutated to mimic the phosphorylated or unphosphorylated state, and the phenotypes produced by transgenes that express the mutant subunits will be analyzed. (3) In a third mechanism, specific binding partners or effector proteins might mediate the targeting of the dynein motor to specific cargoes or locations. Previous studies have provided evidence that spectrin mediates the attachment of dynactin and dynein to membranes. Our collaborator, Laura Ranum (UMN), recently discovered that Spinocerebellar ataxia type 5 (SCA5), an autosomal dominant neurodegenerative disease, is caused by mutations in 2-III spectrin (SPTBN2). In Drosophila, we have shown that mutant, but not wild type, human ss-III spectrin expressed in neurons causes neurodegeneration and a rough eye phenotype. One goal is to conduct a genome-wide screen to recover modifier loci that identify novel genes in the pathogenic process. A second priority is to determine if mutations in human spectrins, and the corresponding mutations in fly ss spectrin, disrupt axonal vesicular transport in Drosophila. These studies will help to elucidate the molecular underpinnings of SCA5 pathology and neurodegenerative disease. PUBLIC HEALTH RELEVANCE: We are studying the molecular basis of intracellular transport. Our work focuses on the microtubule motor cytoplasmic dynein and the mechanisms by which this motor can accomplish diverse transport tasks. Perturbations in intracellular transport are implicated in human diseases, including neurodegenerative disease, cancer, and birth defects.

描述（由申请人提供）：分子运动蛋白在多种细胞内运输过程中发挥作用，包括细胞器运输、染色体分离、轴突运输和信号传导途径。运动依赖性过程对于细胞和组织的生长、增殖和分化至关重要。如何在发育背景下调节运动功能，以及运动功能障碍与包括神经退行性疾病和癌症在内的众多医学问题的关系，是当前研究活动的焦点。我们的工作重点是微管运动细胞质动力蛋白，以及关于这种单一运动亚型如何完成多项任务的重要且尚未解答的问题。我们的目标将解决可能调节动力蛋白靶向和/或活性的三种机制。 (1)首先，细胞质动力蛋白含有多个亚基。各个亚基或亚基域可以指定动力蛋白连接的位置和内容。目标 1 包括生物化学和遗传实验，以解决动力蛋白轻链和轻中间链如何影响动力蛋白功能。 (2)其次，动力蛋白亚基的翻译后修饰可能控制动力蛋白亚基活性或结合亲和力。我们正在定义动力蛋白亚基上磷酸化的体内位点，并将研究靶位点的重要性。 LIC 亚基上的靶位点将被突变以模拟磷酸化或非磷酸化状态，并且将分析表达突变亚基的转基因产生的表型。 (3)在第三种机制中，特定的结合伴侣或效应蛋白可能介导动力蛋白马达靶向特定的货物或位置。先前的研究提供了证据表明血影蛋白介导动力蛋白和动力蛋白与膜的附着。我们的合作者 Laura Ranum (UMN) 最近发现 5 型脊髓小脑共济失调 (SCA5) 是一种常染色体显性遗传神经退行性疾病，是由 2-III 血影蛋白 (SPTBN2) 突变引起的。在果蝇中，我们发现神经元中表达的突变型而非野生型人类 ss-III 血影蛋白会导致神经变性和粗糙的眼睛表型。一个目标是进行全基因组筛选，以恢复识别致病过程中新基因的修饰位点。第二个优先事项是确定人类血影蛋白的突变以及果蝇 ss 血影蛋白的相应突变是否会破坏果蝇的轴突囊泡运输。这些研究将有助于阐明 SCA5 病理学和神经退行性疾病的分子基础。公共卫生相关性：我们正在研究细胞内运输的分子基础。我们的工作重点是微管马达细胞质动力蛋白以及该马达完成不同运输任务的机制。细胞内运输的扰动与人类疾病有关，包括神经退行性疾病、癌症和出生缺陷。