A Helical Membrane-Binding Domain Targets the Toxoplasma ROP2 Family to the Parasitophorous Vacuole
A Helical Membrane-Binding Domain Targets the Toxoplasma ROP2 Family to the Parasitophorous Vacuole
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DOI：
10.1111/j.1600-0854.2009.00958.x
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发表时间：
2009-10-01
期刊：
影响因子：
4.5
通讯作者：
Boothroyd, John C.
中科院分区：
文献类型：
--
作者：
Reese, Michael L.;Boothroyd, John C.
在入侵过程中，专性细胞内病原体，刚地弓形虫，分泌到其宿主细胞的各种效应分子，其中几个已经牵连在疾病的菌株特异性变异。这些效应子中最大的家族，由典型成员ROP 2定义，在分泌后迅速与新生的寄生虫空泡膜（PVM）相关联。在这里，我们证明了ROP 2家族的NH 2-末端结构域包含一系列的两亲性螺旋，这是必要的和足够的膜协会。虽然每个两亲性螺旋都能单独结合细胞膜，但它们一起优先结合PVM，可能是通过感知其强的负曲率。这种以前未表征的螺旋结构域是膜缔合的进化稳健和能量有效的设计。
During invasion, the obligate intracellular pathogen, Toxoplasma gondii, secretes into its host cell a variety of effector molecules, several of which have been implicated in strain-specific variation in disease. The largest family of these effectors, defined by the canonical member ROP2, quickly associates with the nascent parasitophorous vacuole membrane (PVM) after secretion. Here we demonstrate that the NH2-terminal domain of the ROP2 family contains a series of amphipathic helices that are necessary and sufficient for membrane association. While each of the amphipathic helices is individually competent to bind cellular membranes, together they act to bind the PVM preferentially, possibly through sensing its strong negative curvature. This previously uncharacterized helical domain is an evolutionarily robust and energetically efficient design for membrane association.