CENTROSOME FORMATION, FUNCTION AND REPRODUCTION

中心体的形成、功能和繁殖

基本信息

批准号：
3278630
负责人：
GREENFIELD SLUDER
金额：
$ 27.68万
依托单位：
WORCESTER FOUNDATION FOR BIOMEDICAL RES
依托单位国家：
美国
项目类别：
财政年份：
1982
资助国家：
美国
起止时间：
1982-05-01 至 1995-06-30
项目状态：
已结题

项目摘要

Centrosomes for the poles of the mitotic spindle. Since they nucleate all spindle microtubules, centrosomes play a key role in the execution of mitotic events. The duplication, or reproduction, of the interphase centrosome is an important event in the cell's preparations for mitosis. We will characterize the functional properties of the mechanisms that control centrosome reproduction and the mechanisms that coordinate the centrosome cycle with the nuclear cell cycle. This sort of information cannot be gained solely by the biochemical characterization of isolated centrosomes. Our long range goal is to provide the groundwork for new technologies to control the proliferation of cancerous cells. 1. To investigate the how centrosome reproduction is coordinated with the nuclear cell cycle in sea urchin zygotes, we will test the role of maturation promoting factor levels in the reproducing of centrosomes. We will also examine the possibly that the cyclin A-p34cdc2 and cyclin B-p34cdc2 kinase complexes have separate roles in both centrosome reproduction and the nuclear cell cycle. 2. We will examine the mechanisms that control centrosome reproduction using cell-free Xenopus egg extracts. Exogenous controsomes are active in cycling egg extracts. We will determine the extent to which chromosomes can reproduce in extracts that are arrested i mitosis. Next, we will examine the role of the p34cdc2 kinase in the reproduction of centrosomes. 3. We will test the role of the nine triplet microtubules of the centriole in centrosome formation and reproduction by three complementary methods. a. We extract the triplet microtubules from isolated centrioles and show that the remnants organize centrosomes. We will deermine if these centrosomes reproduce in sea urchin zygotes and Xenopus egg extracts and if so, see if daughter centrioles with nine triplet microtubule morphology are assembled. b. To determine if the nine triplet microtubule stucture alone is sufficient to organize a centrosome, we will assay the ability of basal bodies, which may not organize centrosomes in vivo, to form functional centrosomes in Xenopus egg extracts. These experiments will enable us to determine if basal body duplication can be uncoupled from centrosome formation and reproduction. c. We will introduce centrosomes from "acentriolar" cells into Xenopus egg extracts to determine if they form centrosomes in an animal cytoplasm and if those centrosomes reproduce in a normal fashion. 4. To characterize the mechanisms that control centrosome inheritance in the development, we will detrmine when the matrnal centrosome is suppressed in the development of starfish zygotes. We will transfer meiosis I and meiosis II spindles from maturing eggs to zygotes in first mitosis.

有丝分裂纺锤体两极的中心体。由于它们成核所有纺锤体微管、中心体在执行中发挥关键作用有丝分裂事件。间期的复制或复制中心体是细胞有丝分裂准备过程中的一个重要事件。我们将描述这些机制的功能特性控制中心体复制和协调中心体复制的机制中心体周期与核细胞周期相同。这类信息不能仅通过分离的生化特征来获得中心体。我们的长期目标是为新的控制癌细胞增殖的技术。 1. 至研究中心体繁殖如何与海胆受精卵的核细胞周期，我们将测试其作用中心体复制中的成熟促进因子水平。我们还将检查细胞周期蛋白 A-p34cdc2 和细胞周期蛋白的可能性 B-p34cdc2 激酶复合物在两个中心体中具有不同的作用生殖和核细胞周期。 2. 我们将检查使用无细胞爪蟾控制中心体繁殖的机制鸡蛋提取物。外源控制体在鸡蛋提取物的循环中具有活性。我们将确定染色体可以繁殖的程度有丝分裂被阻止的提取物。接下来我们就来看看它的作用中心体复制中的 p34cdc2 激酶。 3.我们将测试中心粒的九个三联体微管在中心体中的作用通过三种互补的方法形成和繁殖。一个。我们从分离的中心粒中提取三联体微管并表明残余物组织中心体。我们将确定这些是否中心体在海胆受精卵和非洲爪蟾卵提取物中繁殖如果是这样，看看子代中心粒是否有九个三联体微管形态被组装。 b.判断是否是九个三元组仅微管结构就足以组织中心体，我们将检测基体的能力，基体可能无法组织体内中心体，在爪蟾卵中形成功能性中心体提取物。这些实验将使我们能够确定基底体是否复制可以与中心体形成和繁殖脱钩。 c.我们将把来自“acentriolar”细胞的中心体引入非洲爪蟾鸡蛋提取物以确定它们是否在动物中形成中心体细胞质以及这些中心体是否以正常方式繁殖。 4. 至描述控制中心体遗传的机制发育，我们将确定母体中心体何时受到抑制在海星受精卵的发育过程中。我们将转移减数分裂 I 和减数分裂 II 纺锤体从成熟卵到第一次有丝分裂中的受精卵。