Analysis of Septin Structure and Function

Septin结构与功能分析

• 批准号: 10532365
• 负责人: Erfei Bi
• 金额: $ 39.82万
• 依托单位: UNIVERSITY OF PENNSYLVANIA
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-26 至 2024-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10532365
• 关键词: Actomyosin; Alzheimer' s Disease; Anaphase; Architecture; Bacterial Infections; Basic Science; Binding Proteins; Biological Models; Cell membrane; Cell physiology; Cells; Cellular Structures; Complex; Cytokinesis; Cytoskeleton; Data; Daughter; Defect; Dendritic Spines; Diffusion; Electron Microscopy; Environment; Excision; Filament; Genes; Higher Order Chromatin Structure; Human; Imaging technology; Infertility; Malignant Neoplasms; Mammalian Cell; Mitotic; Modeling; Morphogenesis; Mothers; Mutation; Myosin Type II; Neck; Neurodegenerative Disorders; Organism; Parkinson Disease; Phosphorylation; Phosphotransferases; Platinum; Play; Process; Protein Dephosphorylation; Protein Kinase; Protein phosphatase; Proteins; Public Health; Regulation; Research; Resolution; Rod; Role; STK11 gene; Saccharomyces cerevisiae; Saccharomycetales; Shapes; Site; Spermiogenesis; Structure; System; Testing; Visualization; Yeasts; anillin; cell motility; cilium biogenesis; constriction; hereditary neuropathy; imaging modality; insight; light microscopy; molecular assembly/self assembly; overexpression; scaffold; tool; tumorigenesis; ultra high resolution; yeast genetics

Project Summary/Abstract: Septins from all organisms including yeast and humans form rod-shaped heterooligomeric complexes that are assembled into linear filaments and other higher-order structures such as rings and hourglasses. These structures act as a cellular scaffold and/or diffusion barrier to impact diverse cellular functions including cytokinesis, cell migration, ciliogenesis, dendritic spine morphogenesis, spermiogenesis, and bacterial infection. Mutations in septin genes cause hereditary neuropathy and infertility in humans. Septins are also implicated in tumorigenesis and neurodegenerative diseases such as Alzheimer's and Parkinson's. Thus, understanding septin structure and function is critically important not only for basic science but also for public health. However, it remains largely unknown how septins are assembled and dynamically remodeled into various cellular architectures to perform distinct functions in any system. Since the initial discovery of septins in the budding yeast Saccharomyces cerevisiae, this organism has served as a highly effective model for uncovering the general principles of septin assembly and function. By combining the power of yeast genetics and cell synchronization with cutting-edge imaging technologies including platinum-replica electron microscopy and super-resolution light microscopy, we have determined the architectures of the native septin structures in budding yeast. Septins form an “early hourglass” at the division site that consists of paired septin filaments arranged in parallel to the mother-daughter axis. This structure matures into a “zonal transitional hourglass” in anaphase, with a septin gauze at the outer zones and myosin-II filaments in the mid-zone. The transitional hourglass is then remodeled into a “septin double ring” that consists of circumferential paired and single filaments. The double ring now sandwiches a constricting actomyosin ring. Both structures act together to restrict diffusible factors at the division site during cytokinesis. Recent evidence suggests that septins also undergo architectural remodeling from an hourglass-shaped structure during furrow ingression to a double ring-like structure during abscission in mammalian cells. In this application, we will: (Aim 1) determine how septin high-order assembly and stability at the division site is controlled by a LKB1-like kinase before cytokinesis in yeast; (Aim 2) determine how septin architectural remodeling is controlled by a RhoGEF-anillin module during cytokinesis in yeast; and (Aim 3) determine the septin architectures and their regulation by ArhGEF18 and anillin during furrow ingression and abscission in mammalian cells. The proposed study is expected to significantly advance our mechanistic understanding of septin assembly, remodeling, and function across model systems.

项目摘要/摘要： 来自包括酵母和人类在内的所有生物体的脓蛋白形成杆状异寡聚复合物， 被组装成线性细丝和其他高阶结构，例如环和沙漏。 结构充当细胞支架和/或扩散屏障，影响多种细胞功能，包括 胞质分裂、细胞迁移、纤毛发生、树突棘形态发生、精子发生和细菌 Septin 基因突变也会导致人类遗传性神经病和不孕症。 与肿瘤发生和神经退行性疾病如阿尔茨海默病和帕金森病有关。 了解 septin 的结构和功能不仅对于基础科学而且对于公众都至关重要 然而，脓毒症是如何组装和动态重塑的仍然很大程度上未知。 各种蜂窝架构在任何系统中执行不同的功能。 自从在芽殖酵母酿酒酵母中首次发现脓毒蛋白以来，这种生物体已经 作为揭示 septin 组装和功能一般原理的高效模型。 将酵母遗传学和细胞同步的力量与尖端成像技术相结合 包括铂复制品电子显微镜和超分辨率光学显微镜，我们已经确定 出芽酵母中的天然脓蛋白结构的结构形成了“早期沙漏”。 由平行于母女轴排列的成对脓蛋白丝组成的分裂位点。 结构在后期成熟为“区域过渡沙漏”，外部区域有隔膜纱布 中间区域的肌球蛋白-II 细丝随后被重塑为“septin 双”。 “环”由圆周成对和单丝组成，双环现在夹着一个。 收缩肌动球蛋白环。两种结构共同作用以限制分裂位点的扩散因子。 最近的证据表明脓毒症也经历了结构重塑。 沟侵入时的沙漏形结构到脱落时的双环状结构 在此应用中，我们将：（目标 1）确定 septin 如何进行高阶组装和稳定性。 在酵母胞质分裂之前，分裂位点由 LKB1 样激酶控制（目标 2）； septin 结构重塑在酵母胞质分裂过程中由 RhoGEF-anillin 模块控制； （目标 3）确定脓蛋白结构及其在犁沟过程中 ArhGEF18 和苯胺的调节 哺乳动物细胞的进入和脱落。预计这项研究将显着推进我们的研究。 对跨模型系统的 septin 组装、重塑和功能的机械理解。