Chromosome Movement in Prometaphase

前中期染色体运动

• 批准号: 7282358
• 负责人: GARY J. GORBSKY
• 金额: $ 34.18万
• 依托单位: OKLAHOMA MEDICAL RESEARCH FOUNDATION
• 依托单位国家: 美国
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-01-01 至 2009-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7282358
• 关键词: Affect; Anaphase; Aneuploidy; Behavior; Binding; Binding Sites; Biochemical; Biological; Cell Cycle Progression; Cell Cycle Regulation; Cells; Chromosome Arm; Chromosomes; Class; Clip; Complex; Cytolysis; Cytoplasm; Data; Dynein ATPase; Health; Human; In Vitro; Individual; Kinesin; Kinetochores; Laboratories; Lateral; Life; Mammalian Cell; Maps; Measures; Mechanics; Mediating; Mediator of activation protein; Meiosis; Metaphase; Metaphase Plate; Methods; Microtubule Proteins; Microtubules; Mitosis; Mitotic; Mitotic spindle; Mitotic/Spindle Checkpoint; Modeling; Molecular; Motion; Movement; Organelles; Phosphorylation; Phosphorylation Site; Phosphotransferases; Play; Plus End of the Microtubule; Prometaphase; Protein Dynamics; Proteins; Regulation; Research Personnel; Role; Signal Transduction; Signaling Molecule; Sister; Source; System; Testing; Thinking; Time; Xenopus; aurora B kinase; chromokinesin; chromosome movement; dynactin; egg; in vivo; mutant; novel; novel strategies; prevent; programs; protein function; retinal rods; tool

DESCRIPTION (provided by applicant): We seek to understand, at the cell biological and molecular levels, how chromosomes move, how they are guided to the metaphase plate, and how microtubule interactions with the kinetochore and other mitotic organelles regulate the mitotic spindle checkpoint. Chromosome movements during prometaphase are driven primarily by dynamic interactions of the mitotic spindle microtubules with the kinetochores. At the same time, kinetochores lacking stable bipolar attachment to microtubules serve to signal the spindle checkpoint that blocks anaphase onset until metaphase alignment is achieved. This checkpoint is silenced when the all sister kinetochores establish stable bipolar microtubule attachments. Thus, chromosome attachment and movement on the mitotic spindle are intimately intertwined with the regulation of the spindle checkpoint. Previously, this lab provided evidence that translocation of the kinetochores along microtubules is the prime mediator of chromosome movement in mitosis. We later discovered that individual kinetochores within a mitotic cell were biochemically distinct and developed the model of kinetochores as catalytic sources for spindle checkpoint signaling. We have now assembled a unique set of tools to dissect the molecular roles of several of the most important regulators of chromosome movement and the spindle checkpoint in vertebrate cells. We will determine if and how microtubule attachment and mechanical tension regulate kinetochore protein dynamics and signaling. We focus on a set of key regulators of microtubule-kinetochore interactions: the Ndc80 protein complex, Polo-like kinase1, the Aurora B kinase, the dynein/dynactin complex and an associated protein complex, the ZW10/Rod complex. We will analyze the functions of these proteins in living Xenopus and mammalian cells. We will recapitulate kinetochore regulation in lysed cell systems, in fractions from mitotic cells, and with purified proteins in vitro. We will collaborate to conduct complementary studies in Xenopus egg extracts. Analyzing the roles of several dynamic protein complexes is a significant challenge. However, only by approaching kinetochore and microtubule protein dynamics in concert with a variety of in vivo and in vitro approaches can we begin to understand the regulation of mitosis in living cells.

描述（由申请人提供）：我们试图在细胞生物学和分子水平上了解染色体如何移动，它们如何被引导到中期板，以及微管与动粒和其他有丝分裂细胞器的相互作用如何调节有丝分裂纺锤体检查点。前中期的染色体运动主要由纺锤体微管与动粒的动态相互作用驱动。与此同时，缺乏稳定的双极附着微管的动粒起到信号纺锤体检查点的作用，该检查点阻止后期开始，直到实现中期对齐。当所有姐妹着丝粒建立稳定的双极微管附着时，该检查点沉默。因此，有丝分裂纺锤体上的染色体附着和运动与纺锤体检查点的调节密切相关。此前，该实验室提供的证据表明，动粒沿着微管的移位是有丝分裂中染色体运动的主要介质。我们后来发现，有丝分裂细胞内的单个动粒在生物化学上是不同的，并开发了动粒作为纺锤体检查点信号传导的催化源的模型。我们现在已经组装了一套独特的工具来剖析脊椎动物细胞中染色体运动和纺锤体检查点的几个最重要的调节因子的分子作用。我们将确定微管附着和机械张力是否以及如何调节动粒蛋白动力学和信号传导。我们专注于一组微管动粒相互作用的关键调节因子：Ndc 80蛋白复合物，Polo样激酶1，极光B激酶，动力蛋白/动力肌动蛋白复合物和相关的蛋白复合物，ZW 10/杆复合物。我们将分析这些蛋白质在活爪蟾和哺乳动物细胞中的功能。我们将概括在裂解细胞系统中，在有丝分裂细胞的组分中，以及在体外用纯化的蛋白质对动粒的调节。我们将合作进行非洲爪蟾卵提取物的补充研究。分析几种动态蛋白质复合物的作用是一个重大的挑战。然而，只有通过接近动粒和微管蛋白动力学与各种体内和体外的方法，我们才能开始了解活细胞有丝分裂的调节。