title: Dynamics of brush border remodeling induced by enteropathogenic E. coli.
abstract: Enteropathogenic Escherichia coli (EPEC) induces dramatic remodeling of enterocyte brush borders, a process that includes microvillar effacement and actin pedestal formation. Although the Arp2/3 complex is involved in formation of a branched actin network within pedestals, the fate of parallel actin bundles in microvilli during infection remains unclear. Here, we find that in polarized intestinal epithelial cells, EPEC stimulates long-range microvillar dynamics, pulling protrusions toward sites of bacterial attachment in a process mediated by the adhesion molecule protocadherin-24. Additionally, retraction of the EPEC bundle forming pilus stimulates directed elongation of nearby microvilli. These processes lead to coalescence of microvilli and incorporation of the underlying parallel actin bundles into pedestals. Furthermore, stabilization of microvillar actin bundles delays pedestal formation. Together, these results suggest a model where EPEC takes advantage of pre-existing actin filaments in microvillar core bundles to facilitate pedestal formation.
authors: Department of Cell and Developmental Biology; Vanderbilt University Medical Center; Nashville, TN USA.
authors: David A
authors: DA
authors: Shifrin
authors: Department of Cell and Developmental Biology; Vanderbilt University Medical Center; Nashville, TN USA.
authors: Scott W
authors: SW
authors: Crawley
authors: Department of Cell and Developmental Biology; Vanderbilt University Medical Center; Nashville, TN USA.
authors: Nathan E
authors: NE
authors: Grega-Larson
authors: Department of Cell and Developmental Biology; Vanderbilt University Medical Center; Nashville, TN USA.
authors: Matthew J
authors: MJ
authors: Tyska
mesh_terms: D000199:Actins / Q000378:metabolism; D001422:Bacterial Adhesion; D018938:Caco-2 Cells; D020895:Enterocytes / Q000382:microbiology* / Q000502:physiology* / Q000648:ultrastructure; D054308:Enteropathogenic Escherichia coli / Q000502:physiology*; D054884:Host-Pathogen Interactions; D006801:Humans; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D008856:Microscopy, Fluorescence; D008871:Microvilli / Q000502:physiology*
chemical_list: D000199:Actins
keywords: Caco-2BBE; EPEC; brush border; bundle forming pilus; espin; intestine; microvilli