Cellular vacuoles induced by Mycoplasma pneumoniae CARDS toxin originate from Rab9-associated compartments.
Cellular vacuoles induced by Mycoplasma pneumoniae CARDS toxin originate from Rab9-associated compartments.
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DOI：
10.1371/journal.pone.0022877
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发表时间：
2011
期刊：
影响因子：
3.7
通讯作者：
Baseman JB
中科院分区：
文献类型：
--
作者：
Johnson C;Kannan TR;Baseman JB
最近，我们在肺炎支原体中发现了一种adp核糖基化和空泡化的细胞毒素，称为社区获得性呼吸窘迫综合征（CARDS）毒素。在这项研究中，我们发现重组卡（rCARDS）毒素诱导的液泡是酸性的，来自于内吞途径，分别通过摄取中性红和液相标记物路西法黄来确定。此外，我们还证明了rCARDS毒素相关的细胞质空泡的形成受到空泡atp酶抑制剂巴菲霉素A1和离子载体莫能菌素的抑制。为了研究这些空泡的发生机制，我们分析了空泡形成过程中内体和溶酶体膜标记物的分布，并观察了rCARDS毒素诱导的空泡周围内体GTPase Rab9的富集。免疫金标记的Rab9和绿色荧光标记的Rab9过表达进一步证实了空泡关联。晚期内体和溶酶体相关的膜蛋白LAMP1和LAMP2也定位于空泡膜，而晚期内体蛋白Rab7和早期内体标志物Rab5和EEA1则被排除在外。与表达DN- rab7的细胞相比，表达显性阴性（DN） Rab9的HeLa细胞在rCARDS毒素存在下表现出明显减少液泡形成，这突出了Rab9在rCARDS毒素诱导的液泡形成中的重要性。我们的研究结果揭示了rab9与rCARDS毒素诱导的空泡的独特关联，以及它与肺炎支原体感染的特征性组织病理学的可能关系。
Recently, we identified an ADP-ribosylating and vacuolating cytotoxin in Mycoplasma pneumoniae designated Community Acquired Respiratory Distress Syndrome (CARDS) toxin. In this study we show that vacuoles induced by recombinant CARDS (rCARDS) toxin are acidic and derive from the endocytic pathway as determined by the uptake of neutral red and the fluid-phase marker, Lucifer yellow, respectively. Also, we demonstrate that the formation of rCARDS toxin-associated cytoplasmic vacuoles is inhibited by the vacuolar ATPase inhibitor, bafilomycin A1, and the ionophore, monensin. To examine the ontogeny of these vacuoles, we analyzed the distribution of endosomal and lysosomal membrane markers during vacuole formation and observed the enrichment of the late endosomal GTPase, Rab9, around rCARDS toxin-induced vacuoles. Immunogold-labeled Rab9 and overexpression of green fluorescent-tagged Rab9 further confirmed vacuolar association. The late endosomal- and lysosomal-associated membrane proteins, LAMP1 and LAMP2, also localized to the vacuolar membranes, while the late endosomal protein, Rab7, and early endosomal markers, Rab5 and EEA1, were excluded. HeLa cells expressing dominant-negative (DN) Rab9 exhibited markedly reduced vacuole formation in the presence of rCARDS toxin, in contrast to cells expressing DN-Rab7, highlighting the importance of Rab9 function in rCARDS toxin-induced vacuolation. Our findings reveal the unique Rab9-association with rCARDS toxin-induced vacuoles and its possible relationship to the characteristic histopathology that accompanies M. pneumoniae infection.
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影响因子：
3.1
作者：
COVER, TL;PURYEAR, W;BLASER, MJ
通讯作者：
BLASER, MJ
影响因子：
3.1
作者：
HU, PC;COLLIER, AM;BASEMAN, JB
通讯作者：
BASEMAN, JB
DOI：
10.1083/jcb.131.6.1435
发表时间：
1995-12
期刊：
The Journal of cell biology
影响因子：
--
作者：
Feng Y;Press B;Wandinger-Ness A
通讯作者：
Wandinger-Ness A
影响因子：
3.8
作者：
Dallo, SF;Baseman, JB
通讯作者：
Baseman, JB
影响因子：
2.2
作者：
Cognet, I;de Coignac, AB;Gauchat, JF
通讯作者：
Gauchat, JF