Department of Microbiology, Faculty of Medicine, University of Geneva, Switzerland.
Cell Microbiol. 2011 Jun;13(6):787-96. doi: 10.1111/j.1462-5822.2011.01585.x. Epub 2011 Feb 21.
Invasion of host cells by apicomplexan parasites is initiated when specialized secretory organelles called micronemes discharge protein complexes onto the parasite surface in response to a rise in parasite intracellular calcium levels. The microneme proteins establish interactions with host cell receptors, engaging the parasite with the host cell surface, and signal for the immediate exocytosis of another set of secretory organelles named the rhoptries. The rhoptry proteins reprogram the invaded host cell and participate in the formation of the parasitophorous vacuole in which the intracellular parasite resides and replicates. Disengagement of the invading parasite from the host cell receptors involves the action of at least one parasite plasma membrane rhomboid protease, which is concomitantly implicated in a checkpoint that signals the parasite to switch from an invasive to a replicative mode.
当寄生虫细胞内钙离子水平升高时，一种被称为微线体的特殊分泌细胞器会释放蛋白复合物到寄生虫表面，从而引发顶复门寄生虫侵入宿主细胞。微线体蛋白与宿主细胞受体相互作用，使寄生虫与宿主细胞表面结合，并发出信号立即释放另一组称为棒状体的分泌细胞器。棒状体蛋白重编程被入侵的宿主细胞，并参与形成寄生泡，其中包含驻留和复制的细胞内寄生虫。入侵的寄生虫与宿主细胞受体的脱离涉及至少一种寄生虫质膜菱形蛋白酶的作用，同时该蛋白酶也涉及一个检查点，该检查点信号提示寄生虫从侵袭模式切换到复制模式。
