Milton/Trak 1/2 Protein and the Transport of Mitochondria

Milton/Trak 1/2 蛋白和线粒体的运输

• 批准号: 10080033
• 负责人: Thomas L. Schwarz
• 金额: $ 37.17万
• 依托单位: BOSTON CHILDREN'S HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-09-20 至 2022-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10080033
• 关键词: Actins; Adaptor Signaling Protein; Axon; Binding; Biochemical; Biological Assay; Buffers; Cells; Complex; Couples; Cytoplasm; Cytoskeleton; Data; Dendrites; Dissociation; Dynein ATPase; Energy Supply; Equilibrium; GTP Binding; GTPase-Activating Proteins; Guanosine Triphosphate; Guanosine Triphosphate Phosphohydrolases; Heterodimerization; Immobilization; In Vitro; Kinesin; Location; Mediating; Metabolic; Microtubules; Mitochondria; Mitochondrial Proteins; Modeling; Motor; Movement; Mutate; Nature; Neurons; Organelles; Outer Mitochondrial Membrane; PINK1 gene; Parkinson Disease; Pathway interactions; Phenotype; Phosphorylation; Phosphotransferases; Physiological; Proteins; Regulation; Shapes; Signal Pathway; Signal Transduction; Structure; Surface; Synapses; Testing; Ubiquitination; Ursidae Family; Work; aurora B kinase; cell motility; density; in vivo; knock-down; myosin VI; novel strategies; parkin gene/protein; peroxisome; prevent; protein transport; recruit; synaptic inhibition; syntaphilin

Work from this lab and others has established that mitochondrial motility is governed by a motor/adaptor complex that couples both kinesin and dynein motors to the mitochondrial surface. Much, however, remains unknown about how regulation of that complex determines when and where a mitochondrion will stop, or why some mitochondria are long-term stationary, while others only pause briefly before continuing to move. Anchoring proteins are known that can hold mitochondria in place, but the interplay of anchoring proteins and mitochondrial motors is poorly understood. This proposal seeks to understand mechanisms that regulate the assembly of the motor/adaptor complex and signaling pathways that can turn off those motors. The proposal also seeks to understand when mitochondria are merely passively stationary and when they are being actively held in place by an anchor. The exceptional shapes of neurons makes mitochondrial motility and its regulation particularly important so that the branches of axons and dendrites can be properly supplied with mitochondria and certain locations with high energetic demand, such as synapses, can have increased density of mitochondria. This proposal therefore places special emphasis on how mitochondrial dynamics are regulated in axons and on signals that may localize mitochondria to synapses. To better understand mitochondrial regulation, the proposal introduces two novel approaches. One approach is the misdirection of the mitochondrial motor/adaptor complex to peroxisomes so that assembly and regulation of the complex can be studied and mutated away from the endogenous mitochondrial proteins. The other new approach is to use a heterodimerizing agent to attach a constitutively active kinesin motor to mitochondria and thereby test whether mitochondria are being actively held in place by an anchor. In addition, this proposal introduces two new factors that govern the motility of mitochondria, a protein that anchors mitochondria to the actin cytoskeleton, and a kinase that regulates the localization of mitochondria at synapses. In Aim 1 we propose to study how a GTPase domain of Miro regulates the ability of the complex to assemble and what physiological significance there is to the GTPase activity. In Aim 2 we investigate competing models for how elevated Ca2+and the PINK1/Parkin pathway cause mitochondria to stop and ask whether or not they immobilize mitochondria with anchoring proteins. In Aim 3 we investigate the mechanism by which Aurora kinase B inhibits mitochondrial movement and thereby promotes the localization of mitochondria to synapses.

该实验室和其他人的工作已经确定线粒体运动受电机/适配器的约束 复合物使动力蛋白和动力蛋白电动机伴随着线粒体表面。但是，仍然有很多东西 关于该复合物的调节如何确定线粒体何时何地停止的尚不清楚，或者为什么 一些线粒体是长期的，而另一些线​​粒体仅在继续移动之前短暂停留。 锚定蛋白已知可以将线粒体固定在适当的位置，但锚定蛋白质的相互作用和 线粒体电动机的理解很少。该提议旨在了解规范的机制 电动机/适配器复合物和信号通路的组装，可以关闭这些电动机。提案 还试图了解线粒体何时仅是被动固定的，何时积极 由锚定在适当的位置。神经元的特殊形状使线粒体运动及其调节 特别重要，以便可以将轴突和树突的分支与线粒体正确提供 以及某些具有高能需求的位置，例如突触，可以增加密度的密度 线粒体。因此，该建议特别强调了如何调节线粒体动力 在轴突和信号中，可能将线粒体定位为突触。更好地了解线粒体 该提案介绍了两种新方法。一种方法是误导 线粒体运动/适配器复合物至过氧化物酶体，因此可以进行组装和调节 研究并从内源性线粒体蛋白中进行了突变。另一种新方法是使用 异二聚体剂以将组成型活性驱动蛋白运动连接到线粒体上，从而测试是否是否 线粒体被锚积极地固定在适当的位置。此外，该提案介绍了两个新的 控制线粒体运动的因素，线粒体是一种将线粒体锚定在肌动蛋白细胞骨架上的蛋白质， 以及调节线粒体在突触中定位的激酶。在目标1中，我们建议研究如何 Miro的GTPase结构域调节复合物组装的能力以及生理意义 GTPase活动存在。在AIM 2中，我们调查了CA2+和如何提高的竞争模型 pink1/parkin途径导致线粒体停止并询问他们是否将线粒体固定在 锚定蛋白质。在AIM 3中，我们研究了Aurora激酶B抑制线粒体的机制 运动，从而促进线粒体将线粒体定位到突触。