Cellular Remodeling by Microtubule Severing

通过微管切断进行细胞重塑

• 批准号: 8667814
• 负责人: JENNIFER L ROSS
• 金额: $ 30.22万
• 依托单位: ALBERT EINSTEIN COLLEGE OF MEDICINE
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-07-01 至 2018-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8667814
• 关键词: ATP phosphohydrolase; Actins; Animal Model; Basic Science; Biophysical Process; Biophysics; Cardiovascular Diseases; Cell Polarity; Cell division; Cell model; Cell physiology; Cells; Cellular Assay; Centrosome; Clinical; Collaborations; Complex; Cytoskeleton; Data; Development; Disease; Enzymes; Etiology; Excision; Generations; Goals; Health; Human; Human Development; Image Analysis; In Vitro; Injury; Knowledge; Life; Maintenance; Malignant Neoplasms; Mammalian Cell; Mammals; Massachusetts; Medicine; Membrane; Mental Retardation; Methods; Microtubule Proteins; Microtubules; Minus End of the Microtubule; Modeling; Molecular; Morphogenesis; Movement; Names; Normal Cell; Paper; Pathology; Physics; Physiology; Positioning Attribute; Process; Proteins; Published Comment; Publishing; Regulation; Research; Research Proposals; Role; Signal Transduction; Somatic Cell; Testing; Testis; Translating; Tubulin; Universities; Work; Wound Healing; base; cell motility; cell type; cellular imaging; college; in vivo; insight; katanin; member; neovascularization; novel; novel therapeutics; polymerization; prevent; professor; programs; public health relevance; reconstitution; repaired; response; single molecule; spastin; tissue regeneration; tissue repair

DESCRIPTION (provided by applicant): Rapid remodeling of the microtubule cytoskeleton is essential for normal cell division, motility and morphogenesis. A unique and intriguing class of proteins involved in this remodeling are the microtubule severing enzymes, so named because of their ability to generate internal breaks in the microtubule lattice, in vitro. The studies outlned in this research proposal will elucidate the cellular functions and biophysical mechanisms of action of members of a still poorly understood subfamily of microtubule severing enzymes, termed fidgetins. The founding member of this subfamily, fidgetin, has long been known to be important for mammalian development, yet the mechanistic basis of its developmental functions remains unclear. In a recent study, we showed that human fidgetin is a microtubule severing enzyme and minus-end depolymerase. We have now found that fidgetin and the closely related protein fidgetin-like 2 perform fundamental but distinct roles in the regulation of human cell migration. Fidgetin localizes to the centrosome and normally promotes cell motility. Cells depleted of fidgetin display severe reduction in motility rates. In stark contrast, fidgetin-like 2 associates with microtubules at the cell edge and normally functions to suppress cell movement. Cells lacking fidgetin-like 2 display a several fold increase in their rate of movement. Moreover, we have found that depletion of fidgetin-like 2 promotes wound healing and neovascularization in animal models. We will pursue the following two specific aims that, together, test the central hypothesis that fidgetin and fidgetin-like 2 recognize and modify distinct microtubule subpopulations thereby controlling different parameters of cell movement: Aim 1: Test the hypothesis that Fidgetin normally promotes cell motility by selectively severing and releasing microtubule minus-ends from centrosomes. Aim 2: Test the hypothesis that Fidgetin-like 2 normally suppresses cell motility by shearing the plus-ends of dynamic microtubules positioned at the cell edge. Our research plan combines complementary state-of-the-art biophysical and cellular approaches to systematically determine 1) how fidgetin and fidgetin-like 2 catalyze the removal of tubulin from the microtubule lattice, 2) how these activities are harnessed in cells to model MT arrays, and 3) how the modeling of cellular MTs by fidgetin or fidgetin-like 2 is translated into altered cell motility. Work will be carried out under the co-direction of David Sharp, an expert cell and molecular biologist, and Jennifer Ross, an expert single molecule biophysicist. Successful completion of the proposed work will provide fundamental insights into the basic mechanisms of microtubule regulation of cell motility, which is a central process in human development and health, and also foundationally establish a body of knowledge for the potential development of novel therapeutic paradigms to enhance tissue regeneration and repair through the manipulation of cell movement.

描述（由申请人提供）：微管细胞骨架的快速重塑对于正常细胞分裂，运动性和形态发生至关重要。这种重塑涉及的独特而有趣的蛋白质是微管切断酶，因此命名是因为它们能够在体外在微管晶格中产生内部断裂。该研究提案中概述的研究将阐明仍然被称为fidgetins的微管切断酶的下属的下属的细胞功能和生物物理机制。长期以来，该亚家族的创始成员fidgetin对哺乳动物的发育很重要，但其发育功能的机理基础尚不清楚。在最近的一项研究中，我们表明人坐立蛋白是微管切断酶和减去末端去聚合酶。现在，我们发现烦躁的蛋白和紧密相关的蛋白坐立素样2在人类细胞迁移的调节中起着基本但独特的作用。 Fidgetin定位于中心体，通常会促进细胞运动。枯竭的细胞表现出严重降低的运动率。与之形成鲜明对比的是，类似于烦躁的2 与细胞边缘的微管相关，通常功能抑制细胞运动。缺乏坐立素的细胞显示其运动速率增加了几倍。此外，我们发现类似于fidgetin的2的耗竭可促进动物模型中的伤口愈合和新血管形成。我们将追求以下两个具体目标，即共同测试了中心假设，即fidgetin和fidgetin类似2识别和修改不同的微管亚群，从而控制细胞运动的不同参数：目标1：测试烦躁的假设，即烦躁的假说通常通过选择性地切断和释放微管糖粒子粒子促进细胞运动性，从而促进细胞运动性。 AIM 2：检验以下假设：烦躁的样子2通常通过剪切位于细胞边缘的动态微管的加端来抑制细胞运动。我们的研究计划结合了系统地确定互补的最先进的生物物理和细胞方法，以确定1）如何催化从微管晶格中催化微管蛋白的去除，2）这些活动如何在细胞中利用细胞中的这些活动来模拟MT阵列，以及如何模拟MTS的MTS MTTISTIL MTSS STRENTITION FRIFTGETIN IS FRIFTGETIN IS FRIDGETIN 2 2 2）。工作将在专家细胞和分子生物学家David Sharp和专家单分子生物物理学家Jennifer Ross的共同指导下进行。成功完成拟议的工作将提供对细胞运动微管调节的基本机制的基本见解，这是人类发展和健康的中心过程，也为基础上建立了知识的基础，以通过操纵细胞运动来增强组织再生和修复的新型治疗范式的潜在发展。