NUCLEAR SHAPE DURING MITOSIS IN FISSION YEAST

裂殖酵母有丝分裂过程中的核形状

• 批准号: 7355020
• 负责人: SHELLEY SAZER
• 金额: $ 0.94万
• 依托单位: UNIVERSITY OF COLORADO
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-09-26 至 2007-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7355020
• 关键词: cell cycle; eukaryote; mitotic spindle apparatus; nuclear membrane; yeasts

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. In the ¿open mitosis¿ of higher eukaryotes the nuclear envelope disperses at the onset of mitosis; after chromosome segregation it is reformed around each of the two sets of chromosomes. In the "closed mitosis¿ of most single celled eukaryotes, including yeast, the nuclear envelope remains intact. The mitotic spindle forms and elongates within the nucleus, resulting in dramatic changes in nuclear shape from round to oblong to dumbbell before the organelle resolves into two discrete daughter nuclei. These morphological changes in mitotic yeast nuclei are well documented (McCully and Robinow, 1971). However, the biophysical properties that govern changes in nuclear shape and size during mitosis remain largely unknown. Several interrelated approaches will be used to understand nuclear structure in mitotic fission yeast cells. First, we will measure the nuclear volume, nuclear envelope surface area, nuclear pore distribution, and asymmetries in nuclear envelope curvature, with respect to mitotic spindle length during mitosis in wild type cells. The measurements will be used for two purposes. First, they will provide the basis for developing a physical model of nuclear division. Second, they will be used for comparison to abnormal situations in which nuclear division is perturbed. Finally, we will determine the sites of nuclear envelope fragmentation in cells undergoing abnormal nuclear division, in order to determine whether the spindle pole bodies and/or the clustered nuclear pores influence the integrity of the nuclear membrane. This study will provide the first accurate description of nuclear size, surface area and shape in fission yeast during mitosis. The data will be used as a basis for development of a biophysical model describing nuclear division in yeast as a point for comparison with mutant yeast strains in which nuclear division is defective.

本子项目是利用由NIH/NCRR资助的中心赠款提供的资源的众多研究子项目之一。子项目和研究者（PI）可能已经从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。列出的机构是中心的，不一定是研究者的机构。在高等真核生物的“开放有丝分裂”中，核膜在有丝分裂开始时分散；在染色体分离之后，它围绕着两组染色体中的每一组进行重组。在包括酵母在内的大多数单细胞真核生物的“闭式有丝分裂”中，核膜保持完整。有丝分裂纺锤体在细胞核内形成并伸长，导致细胞核形状从圆形到椭圆形再到哑铃形的剧烈变化，然后细胞器分解成两个离散的子核。有丝分裂酵母细胞核的这些形态变化有很好的记录（McCully和Robinow， 1971）。然而，控制有丝分裂过程中核形状和大小变化的生物物理特性在很大程度上仍然未知。几个相互关联的方法将被用来了解有丝分裂酵母细胞的核结构。首先，我们将测量野生型细胞有丝分裂过程中核体积、核包膜表面积、核孔分布和核包膜曲率的不对称性，以及与有丝分裂纺锤体长度的关系。测量结果将用于两个目的。首先，它们将为发展核划分的物理模型提供基础。其次，它们将用于与核分裂受到干扰的异常情况进行比较。最后，我们将确定异常核分裂细胞中核膜断裂的位置，以确定纺锤极体和/或聚集的核孔是否影响核膜的完整性。这项研究将首次准确描述分裂酵母在有丝分裂过程中的核大小、表面积和形状。这些数据将被用作发展生物物理模型的基础，该模型描述酵母的核分裂，作为与核分裂有缺陷的突变酵母菌株进行比较的点。