Targeting of an enteropathogenic Escherichia coli (EPEC) effector protein to host mitochondria
Targeting of an enteropathogenic Escherichia coli (EPEC) effector protein to host mitochondria
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DOI：
10.1046/j.1462-5822.2000.00082.x
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发表时间：
2000-12-01
影响因子：
3.4
通讯作者：
Jepson, M
中科院分区：
文献类型：
--
作者：
Kenny, B;Jepson, M
许多革兰氏阴性病原体使用III型分泌装置将效应分子递送到宿主细胞中以破坏有利于病原体的细胞过程。肠致病性大肠杆菌（EPEC）使用这样的系统将Tir效应分子递送到宿主细胞中。在本文中，我们表明，基因上游的TIR，orf 19，编码一个额外的III型分泌效应蛋白。Orf 19通过不依赖于内吞作用但依赖于EspB的机制递送到宿主细胞中。Orf 19靶向宿主线粒体，在那里它似乎干扰维持膜电位的能力。虽然Orf 19的确切作用仍有待阐明，但它与线粒体的相互作用表明，它可能在颠覆这些细胞器的关键功能中发挥作用，例如能量产生或控制细胞死亡。这是第一个靶向线粒体的III型分泌蛋白的例子;很可能同源物（存在于EPEC和志贺氏菌属中）和其他细菌效应物也将靶向这个细胞器。
Many Gram-negative pathogens use a type III secretion apparatus to deliver effector molecules into host cells to subvert cellular processes in favour of the pathogen. Enteropathogenic Escherichia coli (EPEC) uses such a system to deliver the Tir effector molecule into host cells. In this paper, we show that the gene upstream of tir, orf19, encodes an additional type III secreted effector protein. Orf19 is delivered into host cells by a mechanism independent of endocytosis, but dependent on EspB. Orf19 is targeted to host mitochondria, where it appears to interfere with the ability to maintain membrane potential. Although the precise role of Orf19 remains to be elucidated, its interaction with mitochondria suggests a possible role in the subversion of key functions of these organelles, such as energy production or control of cell death. This is the first example of a type III secreted protein targeted to mitochondria; it is probable that homologues (present in EPEC and Shigella species) and other bacterial effecters will also target this organelle.