Host cell egress and invasion induce marked relocations of glycolytic enzymes in Toxoplasma gondii tachyzoites.
Host cell egress and invasion induce marked relocations of glycolytic enzymes in Toxoplasma gondii tachyzoites.
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宿主细胞出口和侵袭引起弓形虫gondii tachyzoites中糖酵解酶的明显迁移。
DOI：
10.1371/journal.ppat.1000188
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发表时间：
2008-10
期刊：
影响因子：
6.7
通讯作者：
Beckers, Con J. M.
中科院分区：
文献类型：
--
作者：
Pomel, Sebastien;Luk, Flora C. Y.;Beckers, Con J. M.
顶复门寄生虫依赖于F-肌动蛋白和肌球蛋白为基础的运动系统，他们的入侵和逃离动物宿主细胞，以及他们的一般运动。在弓形虫和疟原虫物种中，这一过程所需的肌动蛋白丝和肌球蛋白马达位于寄生虫质膜和下面的内膜复合物之间的狭窄空间中，内膜复合物是一组扁平的池，覆盖了质膜的大部分细胞质面。在这里，我们表明，弓形虫运动所需的能量主要来自糖酵解和乳酸的产生。我们还表明，糖酵解酶的弓形虫速殖子经历了一个惊人的搬迁从寄生虫的细胞质到他们的表膜后，弓形虫出口从宿主细胞。具体而言，糖酵解酶似乎被易位到内膜复合物的细胞质面以及质膜和内膜复合物之间的空间。糖酵解酶在寄生虫在细胞外环境中长时间孵育期间保持膜相关，并且直到寄生虫完成对新宿主细胞的入侵后才恢复到细胞质位置。糖酵解酶的易位和从弓形虫表膜似乎发生在响应细胞外[K+]的变化经历在出口和入侵，一个信号，需要[Ca 2 +]c的变化在寄生虫在出口。然而，酶易位不依赖于F-肌动蛋白或完整的微管。我们的观察表明，弓形虫能够在其细胞质和表膜之间重新定位其主要能量来源，以响应退出或进入宿主细胞。我们建议，这种能力使弓形虫优化ATP传递到那些细胞的过程，是最关键的宿主细胞外的生存和细胞内寄生虫的生长和复制所需的。人类的原生动物寄生虫是世界各地疾病的重要原因。其中，顶复门寄生虫是一组特别重要的病原体，因为它们包括疟疾的病原体疟原虫和艾滋病患者的重要致病原因弓形虫。这些寄生虫将它们在受感染的人体内的停留分为两个离散的阶段，负责寄生虫在其宿主中传播的能动细胞外阶段，以及完全用于复制的细胞内阶段。在这里，我们表明，弓形虫搬迁的主要能源时，它的细胞内和细胞外环境之间的移动。这似乎使寄生虫能够优化能量传递到那些对细胞外存活和侵入新宿主细胞至关重要的过程以及随后的细胞内生长和复制所需的过程。
Apicomplexan parasites are dependent on an F-actin and myosin-based motility system for their invasion into and escape from animal host cells, as well as for their general motility. In Toxoplasma gondii and Plasmodium species, the actin filaments and myosin motor required for this process are located in a narrow space between the parasite plasma membrane and the underlying inner membrane complex, a set of flattened cisternae that covers most the cytoplasmic face of the plasma membrane. Here we show that the energy required for Toxoplasma motility is derived mostly, if not entirely, from glycolysis and lactic acid production. We also demonstrate that the glycolytic enzymes of Toxoplasma tachyzoites undergo a striking relocation from the parasites' cytoplasm to their pellicles upon Toxoplasma egress from host cells. Specifically, it appears that the glycolytic enzymes are translocated to the cytoplasmic face of the inner membrane complex as well as to the space between the plasma membrane and inner membrane complex. The glycolytic enzymes remain pellicle-associated during extended incubations of parasites in the extracellular milieu and do not revert to a cytoplasmic location until well after parasites have completed invasion of new host cells. Translocation of glycolytic enzymes to and from the Toxoplasma pellicle appears to occur in response to changes in extracellular [K+] experienced during egress and invasion, a signal that requires changes of [Ca2+]c in the parasite during egress. Enzyme translocation is, however, not dependent on either F-actin or intact microtubules. Our observations indicate that Toxoplasma gondii is capable of relocating its main source of energy between its cytoplasm and pellicle in response to exit from or entry into host cells. We propose that this ability allows Toxoplasma to optimize ATP delivery to those cellular processes that are most critical for survival outside host cells and those required for growth and replication of intracellular parasites. Protozoan parasites of humans are important causes of disease throughout the world. Amongst these, the apicomplexan parasites are an especially important group of pathogens, as they include Plasmodium species, the causative agents of malaria, and Toxoplasma gondii, an important cause of disease in people with AIDS. These parasites divide their stay in the infected human into two discrete stages, the motile extracellular stage that is responsible for parasite spread throughout its host, and the intracellular stage that is devoted entirely to replication. Here we demonstrate that Toxoplasma relocates its main source of energy when it moves between the intracellular and extracellular environment. It appears that this allows the parasite to optimize energy delivery to those processes that are critical for extracellular survival and invasion into new host cells and those required for subsequent intracellular growth and replication.
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影响因子：
15.9
作者：
BECKERS, CJM;ROOS, DS;JOINER, KA
通讯作者：
JOINER, KA
影响因子：
3.6
作者：
Foth, BJ;Stimmler, LM;McFadden, GI
通讯作者：
McFadden, GI
影响因子：
4.8
作者：
Moudy, R;Manning, TJ;Beckers, CJ
通讯作者：
Beckers, CJ
DOI：
10.1084/jem.149.1.172
发表时间：
1979-01-01
期刊：
The Journal of experimental medicine
影响因子：
--
作者：
Miller LH;Aikawa M;Johnson JG;Shiroishi T
通讯作者：
Shiroishi T
影响因子：
--
作者：
Fleige, Tobias;Fischer, Karsten;Bohne, Wolfgang
通讯作者：
Bohne, Wolfgang