CHROMOSOME MOVEMENT IN MEIOSIS AND MITOSIS

减数分裂和有丝分裂中的染色体运动

• 批准号: 2183725
• 负责人: Sharyn A. Endow
• 金额: $ 24.47万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1991
• 资助国家: 美国
• 起止时间: 1991-07-01 至 1999-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2183725
• 关键词: CHROMOSOME; MOVEMENT; MEIOSIS; MITOSIS

The long-term objectives of this project are to identify and characterize the forces that underlie chromosome movement in meiosis and mitosis, including interactions of chromosomes with the spindle and microtubule dynamics involved in spindle assembly and function. The proposed studies focus on ncd, a Drosophila protein related to the microtubule motor protein, kinesin. Ncd is a minus-end microtubule motor required for normal chromosome segregation in oocyte meiosis and mitosis in early embryos. The ncd protein is associated with meiotic spindles and mitotic spindle fibers and centrosomes. The proposed studies will test the hypotheses that 1) ncd functions to assemble bipolar spindles in meiosis and move chromosomes poleward in meiosis and mitosis, and 2) interactions of ncd with microtubules during its mechanochemical cycle differ from those of kinesin, and account for the differences in motility properties of ncd and kinesin. Specific aims are to: 1. Visualize spindle assembly and chromosome movement in wildtype and mutant oocytes and embryos using transformants carrying the A. Victoria green fluorescent protein (GFP) fused to ncd. 2. Screen for and analyze new modifier mutants of ncd to identify proteins that interact with specific ncd mutant alleles. 3. Determine the tubulin subunit(s) to which ncd binds and the site(s) of binding using genetic interactions of ncd with tubulin mutants, molecular analysis, and in vitro binding studies. 4. Design, construct and analyze mutants that specifically affect the ncd ATPase in order to obtain information regarding interactions of the ncd motor with microtubules. The proposed studies address the basis of chromosome movement during meiosis and mitosis, and the role and mechanism of function of the ncd microtubule motor protein. Results of these studies will provide information regarding the molecular forces needed for proper chromosome distribution in dividing cells. Defective chromosome distribution causes aneuploidy and genetic abnormalities, and is associated with cellular transformation in humans.

该项目的长期目标是确定和描述 减数分裂和有丝分裂中染色体运动的基础力量， 包括染色体与纺锤体和微管的相互作用 动力学涉及主轴的装配和功能。 拟议的研究集中在ncd上，这是一种与 微管运动蛋白，驱动蛋白。NCD是一种负端微管马达 卵母细胞减数分裂和有丝分裂中正常染色体分离所需的 早期胚胎NCD蛋白与减数分裂纺锤体有关， 有丝分裂纺锤体纤维和中心体。 拟议的研究将检验以下假设：1）NCD功能 在减数分裂中组装双极纺锤体， 减数分裂和有丝分裂，以及2）NCD与微管的相互作用， 其机械化学循环不同于驱动蛋白， NCD和驱动蛋白运动特性的差异。 具体目标是： 1.可视化野生型和非野生型中的纺锤体组装和染色体运动， 突变的卵母细胞和胚胎，使用携带A.维多利亚 融合到ncd的绿色荧光蛋白（GFP）。 2.筛选和分析NCD的新修饰突变体以鉴定蛋白质 与特定的NCD突变等位基因相互作用。 3.确定NCD结合的微管蛋白亚基和NCD结合的位点。 利用ncd与微管蛋白突变体的遗传相互作用的结合，分子 分析和体外结合研究。 4.设计、构建和分析特异性影响NCD的突变体 ATP酶，以获得关于NCD相互作用的信息。 微管马达 拟议的研究解决了染色体运动的基础， 减数分裂和有丝分裂，以及NCD的作用和机制 微管运动蛋白这些研究的结果将提供 关于正确的染色体所需的分子力的信息 在分裂细胞中的分布。染色体分布缺陷导致 非整倍体和遗传异常，并与细胞 人类的转变。