Department of Molecular and Cell Biology, University of California, Berkeley, California 94720, USA.
Cytoskeleton (Hoboken). 2010 Jan;67(1):13-22. doi: 10.1002/cm.20412.
Cytokinesis is the process by which a cell physically divides in two at the conclusion of a cell cycle. In animal and fungal cells, this process is mediated by a conserved set of proteins including actin, type II myosin, IQGAP proteins, F-BAR proteins, and the septins. To facilitate biochemical and ultrastructural analysis of cytokinesis, we have isolated and partially purified the Saccharomyces cerevisiae cytokinetic apparatus. The isolated apparatus contains all components of the actomyosin ring for which we tested-actin, myosin heavy and light chain, and IQGAP-as well as septins and the cytokinetic F-BAR protein, Hof1p. We also present evidence indicating that the actomyosin rings associated with isolated cytokinetic apparati may be contractile in vitro, and show preliminary electron microscopic imaging of the cytokinetic apparatus. This first successful isolation of the cytokinetic apparatus from a genetically tractable organism promises to make possible a deeper understanding of cytokinesis.
胞质分裂是细胞在细胞周期结束时物理分裂为二的过程。在动物和真菌细胞中，这个过程由一组保守的蛋白质介导，包括肌动蛋白、II 型肌球蛋白、IQGAP 蛋白、F-BAR 蛋白和 septin。为了促进胞质分裂的生化和超微结构分析，我们已经从酿酒酵母中分离并部分纯化了胞质分裂装置。分离出的装置包含我们测试的肌动球蛋白环的所有成分——肌动蛋白、肌球蛋白重链和轻链以及 IQGAP——以及 septin 和胞质分裂 F-BAR 蛋白 Hof1p。我们还提供了证据表明，与分离的胞质分裂装置相关的肌动球蛋白环在体外可能是可收缩的，并显示了胞质分裂装置的初步电子显微镜成像。这是首次从遗传上可操作的生物体中成功分离出胞质分裂装置，有望使人们更深入地了解胞质分裂。
