Project C

项目C

• 批准号: 7925364
• 负责人: Eva Nogales
• 金额: $ 33.73万
• 依托单位: UNIVERSITY OF CALIF-LAWRENC BERKELEY LAB
• 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 2015-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7925364
• 关键词: Anaphase; Aneuploidy; Architecture; BCAS2 gene; Binding; Bioinformatics; Biological Assay; Chromatin; Chromosome Segregation; Chromosomes; Complex; Diffuse; Diffusion; Electron Microscopy; Electrostatics; Elements; Generations; Genetic; Goals; Image Analysis; Kinetochores; Label; Location; Methods; Microtubules; Mitosis; Mitotic; Molecular Probes; Motion; Polymers; Positioning Attribute; Process; Property; Research; Resolution; Role; Site; Structural Models; Structure; Surface; System; Testing; Tubulin; Yeasts; chromosome movement; daughter cell; depolymerization; image reconstruction; protein complex; reconstitution; tumorigenesis

The kinetochore is a network of protein complexes that assembles on centromeric chromatin to act as the connection point between chromosomes and the microtubules that segregate them into daughter cells. During anaphase kinetochores allow chromosomes to track the depolymerizing ends of microtubules, which are the primary site of force generation. Thus, kinetochores not only do not let go of microtubule ends as they breakdown, but are able to harness the energy stored in the microtubule lattice and released during depolymerization to produce processive movement of chromosomes to the spindle poles. In this proposal we aim to probe the molecular mechanisms of directed chromosome motion by examining a set of kinetochore protein complexes that are the site of microtubule attachment. Our approach is to combine activity assays, electron microscopy and image analysis, and bioinformatic methods, in the characterization of fully functional complexes. We are studying the yeast-specific DAM1 complex, which assembles in a microtubule-dependent manner into a ring structure that is able to diffuse on the microtubule surface and to track depolymerizing ends. We are also characterizing the conserved NDC80 complex, and the complete KMN network in yeast, which includes also the MTW1 complex and Spc105. Our ultimate objective is to gain a mechanistic understanding of the molecular interactions governing the dynamic attachment of kinetochores to microtubules. Our structural models would be further tested with our collaborators using the powerful yeast system.

动力学是一个蛋白质复合物网络，在丝粒染色质上组装，充当染色体和微管之间的连接点，将它们隔离到子细胞中。在后期的动物学期间，染色体可以跟踪微管的解聚末端，这是力的主要部位。因此，动力学不仅在分解时不放开微管的末端，而且能够利用储存在微管晶格中的能量并在解聚过程中释放，以产生染色体向纺锤管的过程。在这个建议中，我们 旨在通过检查一组微管附着位点的动力学蛋白络合物来探测定向染色体运动的分子机制。我们的方法是结合活性测定，电子显微镜和图像分析以及生物信息学方法，以表征全功能复合物。我们正在研究酵母特异性的DAM1复合物，该复合物以微管依赖性方式组装成能够在微管表面扩散并跟踪解聚末端的环结构。我们还在表征保守的NDC80复合物，以及酵母中的完整KMN网络，其中还包括MTW1复合物和SPC105。我们的最终目标是对控制动力学在微管的动态附着的分子相互作用获得机械理解。我们的结构模型将使用强大的酵母系统与我们的合作者进行进一步测试。