Targeted mutagenesis of the ring-exported protein-1 of Plasmodium falciparum disrupts the architecture of Maurer's cleft organelles
Targeted mutagenesis of the ring-exported protein-1 of Plasmodium falciparum disrupts the architecture of Maurer's cleft organelles
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DOI：
10.1111/j.1365-2958.2008.06329.x
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发表时间：
2008-08-01
影响因子：
3.6
通讯作者：
Tilley, Leann
中科院分区：
文献类型：
--
作者：
Hanssen, Eric;Hawthorne, Paula;Tilley, Leann
成熟的红细胞没有内部运输机制，因此红细胞内的疟疾寄生虫恶性疟原虫建立了自己的运输系统，将毒力因子输出到红细胞表面。Maurer's clefts是寄生虫衍生的膜结构，形成了这种输出分泌系统的重要组成部分。与高尔基体栓系蛋白序列相似的蛋白质，称为环输出蛋白-1（REX 1），与毛雷尔裂相关。一个REX 1-GFP嵌合体被贩运到毛雷尔的裂缝，并优先与这些结构的边缘，以及与囊泡样结构和茎样延伸，参与拴系毛雷尔的裂缝到其他膜。我们已经产生了表达REX 1截短或缺失的转染的恶性疟原虫。电子显微镜显示REX 1截短突变体的Maurer's裂缝具有堆叠的池，而3D 7亲本系具有未堆叠的Maurer's裂缝。D10寄生虫，失去了9号染色体的右端，包括rex 1基因，也显示出具有堆叠池的毛雷尔裂缝。全长REX 1-GFP在D10寄生虫中的表达恢复了3D 7型非堆叠毛雷尔裂表型。这些研究揭示了REX 1蛋白在决定毛雷尔裂系统超微结构中的重要性。
Mature red blood cells have no internal trafficking machinery, so the intraerythrocytic malaria parasite, Plasmodium falciparum, establishes its own transport system to export virulence factors to the red blood cell surface. Maurer's clefts are parasite-derived membranous structures that form an important component of this exported secretory system. A protein with sequence similarity to a Golgi tethering protein, referred to as ring-exported protein-1 (REX1), is associated with Maurer's clefts. A REX1-GFP chimera is trafficked to the Maurer's clefts and preferentially associates with the edges of these structures, as well as with vesicle-like structures and with stalk-like extensions that are involved in tethering the Maurer's clefts to other membranes. We have generated transfected P. falciparum expressing REX1 truncations or deletion. Electron microscopy reveals that the Maurer's clefts of REX1 truncation mutants have stacked cisternae, while the 3D7 parent line has unstacked Maurer's clefts. D10 parasites, which have lost the right end of chromosome 9, including the rex1 gene, also display Maurer's clefts with stacked cisternae. Expression of full-length REX1-GFP in D10 parasites restores the 3D7-type unstacked Maurer's cleft phenotype. These studies reveal the importance of the REX1 protein in determining the ultrastructure of the Maurer's cleft system.