Single-molecule characterization of cytoplasmic dynein

描述(申请人提供)：细胞质动力蛋白是一种分子马达，在许多过程中起着至关重要的作用，对正确的神经功能至关重要。其不适当的功能会导致神经发育失败(如Miller-Dieker Lissephy)、神经退化和其他认知疾病，如精神分裂症。Dynein的广泛作用是通过调节其与辅助蛋白如Lis1、nude和Nudel的功能而实现的。然而，尽管遗传学研究，无论是通过模式生物的突变，还是通过识别人类疾病的致病/风险因素，都一再证明这些蛋白质处于动力蛋白途径，并且对动力蛋白功能重要--即当它们的功能丧失时，动力蛋白介导的运输受到损害--从机械上无法确定它们的作用，或者它们为什么重要。缺乏这样的知识使理解疾病的进展变得困难，以及使其不可能合理地设计治疗方法来纠正损害。我们的工作在机制水平上准确地确定了不同的辅助因素如何改变动力蛋白的功能，并开始确定这些辅助因素对动力蛋白的影响本身是如何调节的。在机制层面上，我们将更好地理解dynein是如何被裸体关闭，然后又被Lis1重新激活的。在全球水平上，我们将从功能上确定Nudel对dynein功能的影响(如果有的话)，以及nude、Nudel和Lis1的功能如何通过磷酸化改变。由于动力蛋白对神经元功能的许多方面都至关重要，这将重要地推动神经生物学的一般领域，并可能使设计更有针对性的治疗方法成为可能。 公共卫生相关性：基于动力蛋白的运输直接关系到公共健康：疱疹和腺病毒等病毒利用动力蛋白在细胞中传播，线粒体和内体等重要货物由动力蛋白定位。动力蛋白功能的改变与神经退行性变有关。在这里研究的蛋白质Lis1的突变与人类神经发育疾病Miller-Dieker Lissephy有关。

DESCRIPTION (provided by applicant): Cytoplasmic dynein is a molecular motor crucially involved in many processes essential for correct neurological function. Its improper function causes failed neurodevelopment (e.g. Miller- Dieker Lissencephaly), neurodegeneration, and other cognitive diseases such as schizophrenia. The wide range of dynein roles is made possible by tuning its function with accessory proteins such as Lis1, NudE, and NudEL. However, while genetic studies, both via mutagenesis in model organisms, and via identification of causative/risk factors in human disease, have repeatedly established that these proteins are in the dynein pathway and are important for dynein function-that is, dynein-mediated transport is impaired when their function is lost-mechanistically it has been impossible to determine what they do, or why they are important. Lacking such knowledge makes understanding disease progression difficult, as well as making it impossible to rationally design therapeutic approaches to correct the impairments. Our work determines at a mechanistic level exactly how the different cofactors alter dynein function, and starts to determine the ways that these co-factors effects on dynein are themselves regulated. At a mechanistic level, we will better understand how dynein is turned off by NudE, and then re-activated by Lis1. At a global level, we will determine functionally what NudEL does to dynein function (if anything), and how the function of NudE, NudEL, and Lis1 are altered by phosphorylation. Since dynein is crucial for many aspects of neuronal function, this will importantly advance the general field of neurobiology, and possibly allow design of more targeted therapeutic approaches. PUBLIC HEALTH RELEVANCE: Dynein-based transport is directly related to public health: viruses such as herpes and adenovirus employ dynein to spread through cells and important cargos like mitochondria and endosomes are positioned by dynein. Altered dynein function is linked to neurodegeneration. Mutations in the protein Lis1 studied here are linked to the human neurodevelopmental disease Miller-Dieker Lissencephaly.