Structure and Mechanism of the Kinesin-3 Motor KIF1A

Kinesin-3 电机 KIF1A 的结构和机制

• 批准号: 10735818
• 负责人: Arne Gennerich
• 金额: $ 62.17万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-09-01 至 2027-06-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10735818
• 关键词: Affect; Amino Acids; Atrophic; Axon; Binding; Biological Assay; Brain Stem; Cell Nucleus; Cell division; Cell physiology; Complex; Cryoelectron Microscopy; Data; Degenerative Disorder; Dense Core Vesicle; Disease; Docking; Dyes; Elements; Encephalopathies; Engineering; Etiology; Exhibits; Family; Fluorescence; Fluorescence Resonance Energy Transfer; Frequencies; Functional disorder; Generations; Goals; Head; Human; In Vitro; Individual; Inherited; Intellectual functioning disability; Kinesin; Label; Link; Measurement; Mediator; Microcephaly; Microtubules; Modernization; Molecular; Molecular Motors; Motion; Motor; Mutagenesis; Mutation; N-terminal; Neck; Neurodegenerative Disorders; Neurodevelopmental Disorder; Neurons; Nucleotides; Optic Nerve; Output; Pattern; Peripheral Nervous System Diseases; Phenotype; Physiological; Plus End of the Microtubule; Positioning Attribute; Presynaptic Terminals; Property; Protein Engineering; Proteins; Resolution; Series; Severities; Spastic Paraplegia; Structural defect; Structure; Synaptic Vesicles; System; Testing; Therapeutic; Therapeutic Intervention; Time; Work; autism spectrum disorder; autonomic neuropathy; cell motility; cerebral atrophy; de novo mutation; developmental disease; disease-causing mutation; drug development; falls; human disease; improved; innovation; insight; laser tweezer; member; migration; molecular targeted therapies; mutant; nervous system disorder; neuron development; novel; nuclear power; optic tweezer; single molecule; stem cells; tool; unnatural amino acids

Our goal is to define the structural and functional mechanism by which the kinesin-3 motor KIF1A generates force and moves along microtubules, and to define the structural basis of KIF1A-related human diseases. The microtubule (MT) transport system regulates essential eukaryotic activities, including neuronal cell division, neuronal migration and the transport of subcellular cargoes. KIF1A, a member of the kinesin-3 family of MT-associated motor proteins, is a key mediator of these activities as the major generator of MT plus-end-directed motility in neurons. KIF1A’s cargoes include nuclei in dividing brain stem cells and synaptic vesicle precursors and dense core vesicles in axon terminals. Not surprisingly, its dysfunction is implicated in a growing number of neurodevelopmental and neurodegenerative disorders referred to as KIF1A-associated neurological disorder (KAND). Unfortunately, these diseases remain poorly understood, in part because KIF1A’s molecular mechanism remains unclear. For example, while most mutations occur in KIF1A’s motor domain, high-resolution structures of the KIF1A-MT complex do not exist. In addition, it remains unknown why Kif1A is superprocessive but easily gives up under load. In this proposal, we will combine cryo-electron microscopy, single-molecule fluorescence, and optical tweezers-based force measurements with innovative protein engineering to determine why KIF1A is a weak but superprocessive motor, define high-resolution structures of the KIF1A-MT complex as a function of KIF1A’s mechanochemical cycle and determine the structural defects caused by disease mutations in KIF1A. These studies will provide a new understanding of KAND and elucidate molecular targets for therapeutic interventions.

我们的目标是定义驱动蛋白 3 马达 KIF1A 的结构和功能机制 产生力并沿着微管移动，并定义 KIF1A 相关的结构基础 人类疾病。微管（MT）运输系统调节重要的真核活动， 包括神经元细胞分裂、神经元迁移和亚细胞货物的运输。 KIF1A 是 MT 相关运动蛋白的驱动蛋白 3 家族的成员，是 这些活动是神经元中 MT 加末端定向运动的主要产生者。 KIF1A 的 货物包括分裂脑干细胞的细胞核、突触小泡前体和致密核心 轴突末端的囊泡。毫不奇怪，它的功能障碍与越来越多的 称为 KIF1A 相关的神经发育和神经退行性疾病 神经系统疾病（KAND）。不幸的是，我们对这些疾病的部分了解仍知之甚少。 因为KIF1A的分子机制尚不清楚。例如，虽然大多数突变 由于 KIF1A-MT 复合物发生在 KIF1A 的运动域，因此不存在高分辨率结构。 此外，目前还不清楚为什么 Kif1A 具有超处理能力，但在负载下很容易放弃。在 在这个提案中，我们将结合冷冻电子显微镜、单分子荧光和 基于光镊的力测量与创新的蛋白质工程以确定原因 KIF1A 是一种弱但超处理的电机，定义了 KIF1A-MT 的高分辨率结构 复杂作为 KIF1A 机械化学循环的函数并确定结构缺陷 由 KIF1A 疾病突变引起。这些研究将为KAND提供新的理解 并阐明治疗干预的分子靶点。