Mechanisms that control neuronal microtubule polarity

控制神经元微管极性的机制

• 批准号: 10604356
• 负责人: Melissa Rolls
• 金额: $ 33.68万
• 依托单位: PENNSYLVANIA STATE UNIVERSITY, THE
• 依托单位国家: 美国
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-05-01 至 2025-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10604356
• 关键词: Animals; Axon; Behavior; Biological Assay; Biological Models; Cells; Complex; Cytoskeleton; Data; Defect; Dendrite Regeneration; Dendrites; Disease; Drosophila genus; Drosophila inturned protein; Endosomes; Event; Fishes; Foundations; Future; Genes; Genetic; Golgi Apparatus; Growth; Health; Hereditary Spastic Paraplegia; Human; Image; Imaging Device; Individual; Ligands; Link; Maintenance; Mediating; Microtubule Depolymerization; Microtubule Polymerization; Microtubules; Minus End of the Microtubule; Modeling; Molecular; Mutation; Natural regeneration; Nerve Degeneration; Neurodegenerative Disorders; Neurons; Outcome; Pathologic; Pathway interactions; Plus End of the Microtubule; Polymers; Positioning Attribute; Proteins; Regulation; Role; Scaffolding Protein; Signaling Protein; Site; Source; Stimulus; Stress; System; Visualization; WNT Signaling Pathway; Work; axon injury; axon regeneration; experimental study; fly; genetic approach; genetic regulatory protein; improved; neuron regeneration; novel; polymerization; receptor; screening; spastin; tool

Project Summary Neuronal microtubules are intimately interconnected with neuronal health, yet many basic principles that control neuronal microtubule organization remain mysterious. For example, microtubules can be nucleated throughout axons and dendrites, but regulators that position nucleation sites far from the cell body have not been identified. Nucleation is upregulated throughout the neuron by axon injury and stress so it is particularly important to understand how it is controlled. If basic mechanisms that control neuronal microtubule organization are not elucidated, it will be very difficult to understand the relationships between the microtubule regulatory proteins and neurodegeneration. Hereditary spastic paraplegia is genetically one of the simplest forms of neurodegenerative disease, and mutations in the gene that encodes the microtubule severing protein spastin cause 40% of cases. However, how and where spastin functions in mature neurons has not been pinned down, and why its reduction sensitizes neurons to degeneration is also not clear. In this proposal Drosophila is used as a model system in which to efficiently identify basic mechanisms that regulate neuronal microtubules to provide a framework for future work on regeneration and degeneration. Aim 1. An unexpected pathway controls microtubule nucleation in dendrites. Using a screening approach, Wnt signaling proteins emerged as key regulators that position microtubule nucleation sites in dendrites. Preliminary data in this aim indicates Wnt signaling proteins likely activate nucleation on endosomes. These preliminary findings will be strengthened by pairing a new nucleation assay with localization of Wnt signaling proteins and endosomes. Aim 2. The role of severing proteins in converting minus end nucleation to minus end growth. It was recently shown that minus ends grow in dendrites and this is important for polarity control and dendrite regeneration. Preliminary data indicates spastin plays a role in generating growing minus ends. Using new assays to visualize nucleation and severing in combination with genetic tools, how and where microtubules are severed in dendrites will be investigated. Aim 3. Control of disruptive nucleation by a checkpoint system. Microtubule nucleation has the potential to disrupt polarity by generating microtubules in random orientations. Detailed live imaging of growing microtubule plus ends determined that a checkpoint system depolymerizes microtubules nucleated in the “wrong” orientation. Two players required for promoting growth of “right” orientation microtubules have been identified. Their function, localization and interactions with one another will be investigated. Conclusion: We will elucidate fundamental but poorly understood mechanisms that control dendrite microtubule organization to fill in key gaps in our understanding of the neuronal cytoskeleton that are essential context for understanding neuronal regeneration and degeneration.

项目概要 神经元微管与神经元健康密切相关，但许多基本原则 控制神经元微管组织仍然是个谜。例如，微管可以成核 整个轴突和树突，但将成核位点远离细胞体的调节器却没有 已被识别。由于轴突损伤和压力，整个神经元的成核作用上调，因此特别重要 了解它是如何控制的很重要。如果控制神经元微管的基本机制 如果不阐明组织结构，就很难理解微管之间的关系 调节蛋白和神经变性。遗传性痉挛性截瘫是遗传性最简单的一种 神经退行性疾病的形式，以及编码微管切断蛋白的基因突变 40% 的病例由 spastin 引起。然而，spastin 在成熟神经元中如何以及在何处发挥作用尚不清楚。 但为什么它的减少会使神经元对退化变得敏感，目前还不清楚。在这个提案中 果蝇被用作模型系统，可有效识别调节神经元的基本机制 微管为未来的再生和退化工作提供框架。 目标 1. 一种意想不到的途径控制树突中的微管成核。使用筛选 通过这种方法，Wnt 信号蛋白成为定位微管成核位点的关键调节因子。 树突。该目标的初步数据表明 Wnt 信号蛋白可能激活成核作用 内体。这些初步发现将通过将新的成核分析与 Wnt 信号蛋白和内体的定位。 目标 2. 切断蛋白质在将负端成核转变为负端生长中的作用。原来是 最近表明负端在树突中生长，这对于极性控制和树突很重要 再生。初步数据表明，spastin 在产生不断增长的负端方面发挥着作用。使用新的 结合遗传工具可视化成核和切断的分析，了解微管的位置和方式 将研究树突中的切断。 目标 3. 通过检查点系统控制破坏性成核。微管成核具有潜力 通过产生随机方向的微管来破坏极性。生长的详细实时成像 微管正端确定检查点系统解聚在微管中成核的微管 “错误”的方向。促进“正确”方向微管生长所需的两个参与者已被 确定。它们的功能、定位以及彼此之间的相互作用将得到研究。 结论：我们将阐明控制树突的基本但知之甚少的机制 微管组织填补了我们对神经细胞骨架理解的关键空白 了解神经元再生和变性的背景。

项目成果

Principles of microtubule polarity in linear cells.

• DOI: 10.1016/j.ydbio.2022.01.004
• 发表时间: 2022-03
• 期刊: DEVELOPMENTAL BIOLOGY
• 影响因子: 2.7
• 作者: Rolls, Melissa M.

Identification of Proteins Required for Precise Positioning of Apc2 in Dendrites.

• DOI: 10.1534/g3.118.200205
• 发表时间: 2018-05-04
• 期刊: G3 (Bethesda, Md.)
• 作者: Weiner AT;Seebold DY;Michael NL;Guignet M;Feng C;Follick B;Yusko BA;Wasilko NP;Torres-Gutierrez P;Rolls MM
• 通讯作者: Rolls MM

Directed microtubule growth, +TIPs, and kinesin-2 are required for uniform microtubule polarity in dendrites.

• DOI: 10.1016/j.cub.2010.11.050
• 发表时间: 2010-12-21
• 期刊: CURRENT BIOLOGY
• 影响因子: 9.2
• 作者: Mattie, Floyd J.;Stackpole, Megan M.;Stone, Michelle C.;Clippard, Jessie R.;Rudnick, David A.;Qiu, Yijun;Tao, Juan;Allender, Dana L.;Parmar, Manpreet;Rolls, Melissa M.
• 通讯作者: Rolls, Melissa M.

Neuronal polarity in Drosophila: sorting out axons and dendrites.

• DOI: 10.1002/dneu.20836
• 发表时间: 2011-06
• 期刊: DEVELOPMENTAL NEUROBIOLOGY
• 影响因子: 3
• 作者: Rolls, Melissa M.

Bilaterian Giant Ankyrins Have a Common Evolutionary Origin and Play a Conserved Role in Patterning the Axon Initial Segment.

• DOI: 10.1371/journal.pgen.1006457
• 发表时间: 2016-12
• 期刊: PLoS genetics
• 影响因子: 4.5
• 作者: Jegla T;Nguyen MM;Feng C;Goetschius DJ;Luna E;van Rossum DB;Kamel B;Pisupati A;Milner ES;Rolls MM
• 通讯作者: Rolls MM