EspJ effector in enterohemorrhagic E. coli translocates into host mitochondria via an atypical mitochondrial targeting signal
EspJ effector in enterohemorrhagic E. coli translocates into host mitochondria via an atypical mitochondrial targeting signal
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肠出血性大肠杆菌中的 EspJ 效应子通过非典型线粒体靶向信号易位到宿主线粒体中
DOI：
10.1111/j.1348-0421.2010.00218.x
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发表时间：
2010
影响因子：
2.6
通讯作者：
Akio Abe
中科院分区：
文献类型：
--
作者：
Jun Kurushima;Takeshi Nagai;Kanna Nagamatsu;Akio Abe
肠出血性大肠杆菌（EHEC）是一种引起人类腹泻和出血性结肠炎的细菌病原体。为了发挥毒力，肠出血性大肠杆菌利用效应子的一个子集，这些效应子通过III型分泌系统转移到宿主细胞中。EspJ是最近发现的一种III型分泌效应子，在相关病原体如EPEC和啮齿柠檬酸杆菌中是保守的。然而，EspJ的确切功能仍不清楚。在本研究中，我们发现EspJ在宿主细胞中不稳定，这可能归因于从氨基酸编号59开始的N末端部分。使用EspJ衍生物的稳定形式，我们首次证明EspJ具有经由N末端（1-36 a.a.）EspJ的。据报道，线粒体靶向效应物EspF破坏线粒体膜电位，导致诱导宿主细胞死亡。为了进一步研究EspJ在线粒体中的功能，用野生型EPEC、同基因EspJ突变体或EspJ过表达菌株感染HeLa细胞。使用EspJ-突变体的LDH释放测定的结果表明，EspJ效应子似乎不参与细胞毒性。
EHEC is a bacterial pathogen causing diarrhea and hemorrhagic colitis in humans. To exert virulence, EHEC exploits a subset of effectors that are translocated into host cells via the type III secretion system. EspJ, which was recently identified as a type III secreted effector, is conserved in related pathogens such as EPEC andCitrobacter rodentium. However, the exact function of EspJ remains unclear. In the present study, we found that EspJ was unstable in host cells, which might be attributable to the N‐terminal part beginning from amino acid number 59. Using stable forms of EspJ derivatives, we demonstrated for the first time that EspJ has the ability to translocate into mitochondria via an atypical mitochondrial targeting signal at the N terminus (1–36 a.a.) of EspJ. It has been reported that a mitochondrial targeting effector, EspF, disrupts the mitochondrial membrane potential, resulting in an induction of host cell death. To further investigate EspJ function in mitochondria, HeLa cells were infected with wild‐type EPEC, an isogenic EspJ‐mutant or an EspJ‐overexpressing strain. The result of LDH release assay using an EspJ‐mutant showed that the EspJ effector appears not to be involved in cytotoxicity.
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肠出血性大肠杆菌O157:H7 espJ--tccP位点的操纵子结构和基因表达。
影响因子：
2.1
作者：
J. Garmendia;G. Frankel
通讯作者：
G. Frankel
DOI：
10.1073/pnas.0604891103
发表时间：
2006-10-03
影响因子：
11.1
作者：
Tobe, Toru;Beatson, Scott A.;Pallen, Mark J.
通讯作者：
Pallen, Mark J.
影响因子：
4.8
作者：
Nagai, T;Abe, A;Sasakawa, C
通讯作者：
Sasakawa, C
影响因子：
5.8
作者：
Wickham, Mark E.;Lupp, Claudia;Finlay, B. Brett
通讯作者：
Finlay, B. Brett
影响因子：
11.4
作者：
Galmiche, A;Rassow, J;Boquet, P
通讯作者：
Boquet, P