Tran Van Nhieu, G. , Ben-Ze'ev, A. & Sansonetti, P. J. Modulation of bacterial entry into epithelial cells by association between vinculin and the Shigella IpaA invasin. EMBO J. 16, 2717-2729

Unité de Pathogénie Microbienne Moléculaire, INSERM U389, Institut Pasteur, Paris, France.
The EMBO Journal (Impact Factor: 10.43). 06/1997; 16(10):2717-29. DOI: 10.1093/emboj/16.10.2717
Source: PubMed


Shigella flexneri is the causative agent of bacillary dysentery in humans. Shigella invasion of epithelial cells is characterized by cytoskeletal rearrangements and formation of cellular projections engulfing the bacterium in a macropinocytic process. We show here that vinculin, a protein involved in linking actin filaments to the plasma membrane, is a direct target of Shigella during cell invasion. IpaA, a Shigella protein secreted upon cell contact, rapidly associates with vinculin during bacterial invasion. Although defective for cell entry, an ipaA mutant is still able to induce foci of actin polymerization, but differs from wild-type Shigella in its ability to recruit vinculin and alpha-actinin. Presumably, IpaA-vinculin interaction initiates the formation of focal adhesion-like structures required for efficient invasion.

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    • "A role for vinculin during bacterial entry has been reported in the case of Shigella flexneri. Upon contact with epithelial cells, S. flexneri injects the IpaA protein into the host cell cytoplasm, where IpaA directly binds to vinculin inducing a dramatic rearrangement of the actin cytoskeleton to promote bacterial engulfment [24,25]. Vinculin has also been observed to be recruited to S. aureus–host cell contact sites or fibronectin-coated beads in epithelial, but not in endothelial cells [15,16,22]. "
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    BMC Cell Biology 01/2013; 14(1):2. DOI:10.1186/1471-2121-14-2 · 2.34 Impact Factor
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    • "Mice were euthanized, and their small intestines were removed, rinsed with complete DMEM medium (containing 2 mM L-glutamine and 10% fetal calf serum). The length of intestine was opened and submerged in buffer A (in mM: 120 NaCl, 4.7 KCl, 2.4 KCl, 1.2 KH2PO4, 1.2 Na2HP04, 25 NaHCO3, 10 HEPES, 5 EDTA, 0.5 DTT, 0.25% BSA; at pH 7.4 warmed to 37°C) for 20 min with agitation at 240 rpm [44]. Cells were collected by centrifugation (415.73 g – 2000 rpm – for 5 min) at room temperature, washed once with PBS and lysed by sonication (3 times, 10 s). "
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