Format

Send to

Choose Destination
Cell Res. 2010 Jun;20(6):647-64. doi: 10.1038/cr.2010.45. Epub 2010 Apr 6.

Rck of Salmonella enterica, subspecies enterica serovar enteritidis, mediates zipper-like internalization.

Author information

1
INRA, UR1282 Infectiologie Animale et Santé Publique, Nouzilly, France.

Abstract

Salmonella can invade non-phagocytic cells through its type III secretion system (T3SS-1), which induces a Trigger entry process. This study showed that Salmonella enterica, subspecies enterica serovar Enteritidis can also invade cells via the Rck outer membrane protein. Rck was necessary and sufficient to enable non-invasive E. coli and Rck-coated beads to adhere to and invade different cells. Internalization analysis of latex beads coated with different Rck peptides showed that the peptide containing amino acids 140-150 promoted adhesion, whereas amino acids between 150 and 159 modulated invasion. Expression of dominant-negative derivatives and use of specific inhibitors demonstrated the crucial role of small GTPases Rac1 and Cdc42 in activating the Arp2/3 complex to trigger formation of actin-rich accumulation, leading to Rck-dependent internalization. Finally, scanning and transmission electron microscopy with Rck-coated beads and E. coli expressing Rck revealed microvillus-like extensions that formed a Zipper-like structure, engulfing the adherent beads and bacteria. Overall, our results provide new insights into the Salmonella T3SS-independent invasion mechanisms and strongly suggest that Rck induces a Zipper-like entry mechanism. Consequently, Salmonella seems to be the first bacterium found to be able to induce both Zipper and Trigger mechanisms to invade host cells.

PMID:
20368731
DOI:
10.1038/cr.2010.45
[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Nature Publishing Group
Loading ...
Support Center