Flotillin 1 Regulation of Enteropathogenic Escherichia coli Pedestal Length.

BACKGROUND

The attaching and effacing pathogens, enteropathogenic Escherichia coli (EPEC) and enterohemorrhagic E. coli (EHEC), remodel the host actin cytoskeleton to form actin-rich pedestals that anchor the bacteria atop intestinal epithelial cells. Although pedestal formation requires clathrin-endocytic proteins, the role of clathrin-independent proteins like flotillin 1 remain unclear.

METHODS

Flotillin 1 localization in pedestal formation was analyzed using immunofluorescence microscopy during EPEC and EHEC infections in HeLa cells. This protein's function was then examined using competing peptide interference and small interfering RNA (siRNA)-mediated knockdown approaches.

RESULTS

Flotillin 1 localizes to the membranes of EPEC pedestals. Disruption of flotillin 1 membrane association or depletion of flotillin 1 using siRNA resulted in significantly elongated EPEC pedestals. A similar pattern of flotillin 1 localization is seen at EHEC pedestals.

CONCLUSIONS

Our work expands current models of attaching and effacing host-pathogen interactions by highlighting a role for flotillin 1 in controlling pedestal length.