Ambit Audrey, Woods Kerry L, Cull Benjamin, Coombs Graham H, Mottram Jeremy C
Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom.
Eukaryot Cell. 2011 Nov;10(11):1429-38. doi: 10.1128/EC.05118-11. Epub 2011 Sep 16.
The morphological events involved in the Leishmania major promastigote cell cycle have been investigated in order to provide a detailed description of the chronological processes by which the parasite replicates its set of single-copy organelles and generates a daughter cell. Immunofluorescence labeling of β-tubulin was used to follow the dynamics of the subcellular cytoskeleton and to monitor the division of the nucleus via visualization of the mitotic spindle, while RAB11 was found to be a useful marker to track flagellar pocket division and to follow mitochondrial DNA (kinetoplast) segregation. Classification and quantification of these morphological events were used to determine the durations of phases of the cell cycle. Our results demonstrate that in L. major promastigotes, the extrusion of the daughter flagellum precedes the onset of mitosis, which in turn ends after kinetoplast segregation, and that significant remodelling of cell shape accompanies mitosis and cytokinesis. These findings contribute to a more complete foundation for future studies of cell cycle control in Leishmania.
为了详细描述利什曼原虫前鞭毛体复制其单拷贝细胞器并产生子细胞的时间顺序过程，研究了其细胞周期中涉及的形态学事件。利用β-微管蛋白的免疫荧光标记来追踪亚细胞细胞骨架的动态变化，并通过有丝分裂纺锤体的可视化来监测细胞核的分裂，同时发现RAB11是追踪鞭毛袋分裂和线粒体DNA（动基体）分离的有用标记。对这些形态学事件进行分类和定量，以确定细胞周期各阶段的持续时间。我们的结果表明，在大利什曼原虫前鞭毛体中，子鞭毛的挤出先于有丝分裂的开始，而有丝分裂又在动基体分离后结束，并且细胞形状的显著重塑伴随着有丝分裂和胞质分裂。这些发现为利什曼原虫细胞周期调控的未来研究奠定了更完整的基础。
