Spatial and temporal control of mitotic chromosome movements.

有丝分裂染色体运动的空间和时间控制。

• 批准号: 9754508
• 负责人: JASON K STUMPFF
• 金额: $ 20万
• 依托单位: UNIVERSITY OF VERMONT & ST AGRIC COLLEGE
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-09-05 至 2022-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9754508
• 关键词: Address; Affect; Affinity; Binding; Biochemical; Biological Assay; Biophysics; Biosensor; C-terminal; Cell division; Cells; Chromosomes; Complex; Coupled; Defect; Development; Equilibrium; Event; Exhibits; Fluorescence Resonance Energy Transfer; Genomic Instability; Germ Cells; Goals; Growth; In Vitro; Infertility; Kinesin; Kinetochores; Lysine; Mammalian Cell; Measures; Metaphase; Microtubule-Associated Proteins; Microtubules; Mitosis; Mitotic; Mitotic Chromosome; Mitotic spindle; Modeling; Molecular; Motor; Movement; Mutagenesis; Neck; Phenotype; Phosphorylation; Play; Plus End of the Microtubule; Process; Prometaphase; Protein Dephosphorylation; Protein phosphatase; Proteins; Public Health; Regulation; Research; Role; Signal Transduction; Site; Structure; Syndrome; Testing; Time; Translating; Trisomy; United States; Variant; Work; attenuation; aurora B kinase; aurora kinase; base; biophysical properties; cell motility; chromosome movement; genome integrity; innovation; live cell imaging; neoplastic cell; novel; prevent; recruit; single molecule; treadmill; tumor

PROJECT SUMMARY The alignment of chromosomes during metaphase is one of the most well conserved events in cell division, yet the molecular mechanisms that underlie this process are not understood. As cells progress from prometaphase into metaphase, chromosomes are aligned at the equator of the mitotic spindle through (A) the spatial restriction of their movements and (B) an increase in attachments between kinetochores and microtubules. The mechanisms that temporally coordinate the confinement of chromosome movements with increased attachments have not been identified. The kinesin-like motor Kif18A (kinesin-8) is required for the alignment of all chromosomes in mitotic cells, however, the motor's role in this process is not fully understood. During mitosis, Kif18A concentrates at the plus-ends of kinetochore-microtubules, which generate the primary forces that move chromosomes. The proposed studies will address key questions related to understanding how Kif18A functions mechanistically during chromosome alignment including: (A) how does Kif18A access the plus-ends of kinetochore-microtubules, which are embedded in a dense protein matrix, (B) how do Kif18A ensembles affect kinetochore-microtubule-generated forces, and (C) how does Kif18A increase attachments between kinetochores and microtubules. The primary goal of the proposed work is to answer these questions by determining how Kif18A's biochemical and biophysical properties translate to its complex effects on the movements and attachments of mitotic chromosomes. We hypothesize that the accumulation of Kif18A at kinetochore-microtubule plus-ends temporally coordinates the spatial confinement of chromosome movements with increased kinetochore-microtubule attachments through two independent mechanisms. We will use an approach combining single molecule biophysics, quantitative live cell imaging, and structural mutagenesis to test these predictions.

项目摘要 中期染色体的排列是细胞分裂中最保守的事件之一， 然而，这一过程背后的分子机制尚不清楚。随着细胞从 从前中期到中期，染色体通过（A）在有丝分裂纺锤体的赤道处排列， 它们的运动的空间限制和（B）动粒和动粒之间的附着增加 微管在时间上协调限制染色体运动的机制， 没有发现增加的附件。驱动蛋白样马达Kif 18 A（驱动蛋白-8）是细胞生长所必需的。 然而，在有丝分裂细胞中所有染色体的排列中，马达在这一过程中的作用并不完全 明白在有丝分裂过程中，Kif 18 A集中在着丝粒微管的正端， 产生移动染色体的主要力量。拟议的研究将解决关键问题 与理解Kif 18 A在染色体比对过程中如何机械地发挥作用有关，包括：（A） Kif 18 A是如何进入嵌入在密集的微管中的着丝粒微管的正端的？ 蛋白质基质，（B）Kif 18 A系综如何影响肌动蛋白微管产生的力，以及（C）如何 Kif 18 A是否增加动粒和微管之间的附着。的首要目标 研究人员提出的工作是通过确定Kif 18 A的生物化学和生物物理特性来回答这些问题。 这些特性转化为它对有丝分裂染色体的运动和附着的复杂影响。我们 假设Kif 18 A在着丝粒微管+末端的积累时间上是协调的 染色体运动的空间限制与增加的着丝粒-微管附着 通过两个独立的机制。我们将使用结合单分子生物物理学的方法， 定量活细胞成像和结构诱变来测试这些预测。