HVEM TOMOGRAPHY OF MITOTIC SPINDLES IN POLYPLOID YEAST

多倍体酵母中有丝分裂纺锤体的 HVEM 断层扫描

• 批准号: 7355021
• 负责人: DAVID S PELLMAN
• 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/7355021
• 关键词: adhesions; centromere; emotions; evolution; gene mutation; genes; genome; microtubules; mitotic spindle apparatus; model; polyploidy; publications; sectioning; siblings; spindle pole body; stress; tomography; 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. Polyploidy occurs during development, cellular stress, disease and evolution. Despite its prevalence, little is known about the physiological alterations that accompany polyploidy. The Pellman lab previously described ¿ploidy-specific lethality¿ where a gene deletion that is not lethal in haploid or diploid budding yeast causes lethality in triploids or tetraploids. A genome-wide screen was used to identify ploidy-specific lethal functions. Only 39 in 3540 mutations screens exhibited ploidy-specific lethality. Almost all of these mutations affect genomic stability by impairing homologous recombination, sister chromatid cohesion, or mitotic spindle function. Recent experiments in the Pellman lab show that tetraploids have a high incidence of syntelic/monopolar kinetochore attachments to the spindle pole. A computational model suggests that this defect can be explained by scaling effects. Serial section, dual-axis tomography of forming spindles in tetraploids showed that the surface of the inner plaque of the spindle pole body doubles in area relative to diploid cells, but that microtubule lengths are similar in spindles of different ploidy. Thus, geometric constraints may have profound effects on genome stability. This work has been submitted for publication.

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得主要资金，因此可以在其他CRISP条目中表示。所列机构为中心，不一定是研究者所在机构。多倍体发生在发育、细胞应激、疾病和进化过程中。尽管它的流行，很少有人知道的生理变化，伴随着多倍体。Pellman实验室先前描述了“倍性特异性致死性”，其中在单倍体或二倍体芽殖酵母中不致死的基因缺失导致三倍体或四倍体的致死性。使用全基因组筛选来鉴定倍性特异性致死功能。在3540个突变筛选中仅39个表现出倍性特异性致死性。几乎所有这些突变都通过损害同源重组、姐妹染色单体凝聚或有丝分裂纺锤体功能来影响基因组稳定性。最近在Pellman实验室的实验表明，四倍体有一个高发病率syntelic/单极动粒附件的主轴极。一个计算模型表明，这种缺陷可以解释尺度效应。四倍体纺锤体形成的连续切片、双轴断层扫描显示，纺锤体极体内斑块的表面面积相对于二倍体细胞增加一倍，但微管长度在不同倍性的纺锤体中相似。因此，几何约束可能对基因组稳定性有深远的影响。这项工作已提交出版。