Loading...
Please wait, while we are loading the content...
Similar Documents
Interaction of Ipa proteins of Shigella flexneri with alpha5beta1 integrin promotes entry of the bacteria into mammalian cells
| Content Provider | Semantic Scholar |
|---|---|
| Author | Watarai, Masahisa Funato, Sumiko Sasakawa, Chihiro |
| Copyright Year | 1996 |
| Abstract | Shigella is a genus of highly adapted bacterial pathogens that cause bacillary dysentery in humans. Bacteria reaching the colon invade intestinal epithelial cells by a process of bacterial-directed endocytosis mediated by the Ipa proteins: IpaB, IpaC, and IpaD of Shigella. The invasion of epithelial cells is thought to be a receptor-mediated phenomenon, although the cellular components of the host that interact with the Ipa proteins have not yet been identified. We report here that in a Shigella flexneri invasive system and Chinese hamster ovary (CHO) cell monolayers, the Ipa proteins were capable of interacting directly with alpha5beta1 integrin. The invasive capacity of S. flexneri for CHO cells increased as levels of alpha5beta1 integrin were elevated. When CHO cells were infected with S. flexneri, the tyrosine phosphorylation both of pp 125FAK, an integrin-regulated 125 K focal adhesion kinase, and of paxillin was stimulated. In contrast, an isogenic strain of S. flexneri that was defective in invasion owing to a mutation in its spa32 gene failed to induce such phosphorylation. Under in vitro and in vivo conditions, the released IpaB, IpaC, and IpaD proteins bound to alpha 5 beta 1 integrin in a manner different from that of soluble fibronectin but similar to that of the tissue form of fibronectin. At the site of attachment of S. flexneri to CHO cells, alpha5beta1 integrin converged with polymerization of actin. These data thus suggest that the capacity of Ipa proteins to interact with alpha5beta1 integrin may be an important Shigella factor in triggering the reorganization of actin cytoskeletons. |
| Starting Page | 991 |
| Ending Page | 999 |
| Page Count | 9 |
| File Format | PDF HTM / HTML |
| PubMed reference number | 8642302v1 |
| Volume Number | 183 |
| Journal | The Journal of experimental medicine |
| Alternate Webpage(s) | http://jem.rupress.org/content/jem/183/3/991.full.pdf |
| Language | English |
| Access Restriction | Open |
| Subject Keyword | Chinese Hamster Cytoskeleton Dysentery Dysentery, Bacillary Focal Adhesions Genus Mammals Mutation PXN gene Shigella flexneri Tyrosine Phosphorylation ovarian neoplasm |
| Content Type | Text |
| Resource Type | Article |
