Department of Parasitology, Hygiene Institute, University of Heidelberg Medical School, Im Neuenheimer Feld 324, 69120 Heidelberg, Germany.
Cell Microbiol. 2010 Mar;12(3):362-71. doi: 10.1111/j.1462-5822.2009.01399.x. Epub 2009 Oct 27.
Cellular organelles are usually linked to the cytoskeleton, which often provides a scaffold for organelle function. In malaria parasites, no link between the cytoskeleton and the major organelles is known. Here we show that during fast, stop-and-go motion of Plasmodium sporozoites, all organelles stay largely fixed in respect to the moving parasite. Cryogenic electron tomography reveals that the nucleus, mitochondrion, apicoplast and the microtubules of Plasmodium sporozoites are linked to the parasite pellicle via long tethering proteins. These tethers originate from the inner membrane complex and are arranged in a periodic fashion following a 32 nm repeat. The tethers pass through a subpellicular structure that encompasses the entire parasite, probably as a network of membrane-associated filaments. While the spatial organization of the large parasite organelles appears dependent on their linkage to the cortex, the specialized secretory vesicles are mostly not linked to microtubules or other cellular structures that could provide support for movement.
细胞器官通常与细胞骨架相连，细胞骨架通常为器官功能提供支架。在疟原虫中，尚未发现细胞骨架与主要细胞器之间存在联系。在这里，我们表明，在疟原虫孢子快速、走走停停的运动过程中，所有细胞器在很大程度上相对于移动的寄生虫保持固定。低温电子断层扫描显示，细胞核、线粒体、质体和疟原虫孢子的微管通过长的连接蛋白与寄生虫囊泡相连。这些系绳起源于内膜复合物，并以 32nm 的重复方式排列成周期性结构。这些系绳穿过一个包含整个寄生虫的皮层下结构，可能是作为一个膜相关纤维的网络。虽然大型寄生虫细胞器的空间组织似乎依赖于它们与皮质的连接，但专门的分泌小泡大多与微管或其他可能为运动提供支撑的细胞结构没有连接。
