CONTROL OF CENTROSOME REPRODUCTION AND MITOTIC PROGRESSI

中心体繁殖和有丝分裂进展的控制

• 批准号: 2637514
• 负责人: GREENFIELD SLUDER
• 金额: $ 33.61万
• 依托单位: UNIV OF MASSACHUSETTS MED SCH WORCESTER
• 依托单位国家: 美国
• 财政年份: 1982
• 资助国家: 美国
• 起止时间: 1982-05-01 至 2003-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2637514
• 关键词: CHO cells; Xenopus oocyte; alternatives to animals in research; cell cycle; cell growth regulation; centromere; centrosome; cyclin dependent kinase; cyclins; density gradient ultracentrifugation; electron microscopy; enzyme activity; genetic crossing over; high performance liquid chromatography; immunoprecipitation; light microscopy; meiosis; mitotic spindle apparatus; nondisjunction; phosphoprotein phosphatase; protein purification; sea urchins; tissue /cell culture; video recording system; western blottings

In broad terms our research is directed at elucidating the control mechanisms for cell division. We use living cells and egg extracts to provide information that cannot be obtained from conventional biochemical and molecular approaches. 1. We developed the first Xenopus egg extract that supports multiple rounds of centrosome reproduction. We will finish our characterization of this experimental system and then use it to further investigate the mechanisms that control centrosome reproduction and coordinate it with nuclear events in the cell cycle, with an emphasis on the role of cyclin dependent kinase 2-cyclin E (Cdk2-E) in the regulation of centrosome reproduction. 2. We will characterize the activities of Cdks complexed with cyclins A and E when sea urchin zygotes are arrested in G1 and S phases and correlate these activities with the different abilities of centrosomes to repeatedly reproduce in these cell cycle phases. 3. We will use mammalian somatic cells to test whether the initiation of centriole duplication can occur during G1, without cell cycle progression into S phase. This should provide new insight into the centriole cycle and its cell cycle regulation. 4. We will test the hypothesis that the spindle, not the cytoplasm, provides the competency for the cell to execute the metaphase-anaphase transition. 5. We will use vertebrate somatic cells to study the regulation of chromatid cohesion at the metaphase-anaphase transition. Health relevance: We study the control of centrosome reproduction because a wide variety of human tumors have an abnormally high number of centrosomes; this can directly lead to aneuploidy and genomic instability through the formation of multipolar spindles at mitosis. We study the regulation of chromatid cohesion, because failure of the sister chromatid arms to completely release at anaphase onset directly leads to chromosome breakage or chromosome non-disjunction, either of which leads to genetic damage that can promote neoplastic transformation.

从广义上讲，我们的研究旨在阐明细胞分裂的控制机制。 我们使用活细胞和卵提取物来提供无法通过传统生化和分子方法获得的信息。 1.我们开发了第一个支持多轮中心体繁殖的非洲爪蟾卵提取物。 我们将完成对该实验系统的表征，然后用它来进一步研究控制中心体复制并协调其与细胞周期中的核事件的机制，重点是细胞周期蛋白依赖性激酶 2-细胞周期蛋白 E (Cdk2- E) 中心体繁殖的调节。 2. 我们将表征当海胆受精卵在 G1 和 S 期停滞时，与细胞周期蛋白 A 和 E 复合的 Cdks 的活性，并将这些活性与中心体在这些细胞周期阶段重复繁殖的不同能力相关联。 3. 我们将使用哺乳动物体细胞来测试是否可以在G1期间开始中心粒复制，而无需细胞周期进展到S期。 这将为中心粒周期及其细胞周期调控提供新的见解。 4. 我们将检验以下假设：为细胞提供执行中期-后期转变的能力的是纺锤体，而不是细胞质。 5. 我们将利用脊椎动物体细胞研究中期-后期转变时染色单体凝聚力的调节。 健康相关性：我们研究中心体繁殖的控制，因为多种人类肿瘤具有异常大量的中心体；这可以通过有丝分裂时多极纺锤体的形成直接导致非整倍性和基因组不稳定。 我们研究染色单体凝聚力的调节，因为姐妹染色单体臂在后期开始时未能完全释放直接导致染色体断裂或染色体不分离，这两种情况都会导致可促进肿瘤转化的遗传损伤。