The invasin protein of Yersinia enterocolitica: internalization of invasin-bearing bacteria by eukaryotic cells is associated with reorganization of the cytoskeleton.

Abstract

Abstract. Yersinia enterocolitica, a facultative intracellular pathogen of mammals, readily enters (i.e., invades) cultured eukaryotic cells, a process that can be conferred by the cloned inv locus of the species. We have studied the mechanism by which the product of inv, a microbial outer membrane protein termed "invasin;" mediates the internalization of bacteria by HEp-2 cells and chicken embryo fibroblasts . Invasinbearing bacteria initially bound the filopodia and the leading edges of cultured cells . Multiple points of contact between the bacterial surface and the surface of the cell ensued and led to the internalization of the bacterium within an endocytic vacuole ; the same multistep process could be induced by an inert particle coated with invasin-containing membranes . Both adherence and internalization were blocked by an antisera directed against the 0 1 integrin cell-adherence

Filopodium retraction is controlled by adhesion to its tip

“…Briefly, prior to acquisition cells labelled with a fluorescent membrane dye were incubated with beads. We first used as a bead coating ligand the Yersinia Invasin protein, which specifically binds to b1 integrins and triggers filopodial retraction (Young et al, 1992;Isberg and Barnes, 2001;Vonna et al, 2007). A bead was immobilized in the OTs and approached to a single filopodium emanating from the cell (Fig.…”

“…Several bacteria or viruses also hijack filopodia to invade epithelial or endothelial cells (Lehmann et al, 2005;Romero et al, 2011;Schelhaas et al, 2008;Smith et al, 2008;Young et al, 1992). For example, the Yersinia Invasin protein that binds to b1 integrins and the Shigella Type III Secretion System (T3SS) have been shown to interact with and trigger retraction of filopodia (Romero et al, 2011;Vonna et al, 2007;Young et al, 1992). While forces exerted during cell adhesion or migration have been analysed in many studies, forces associated with filopodia have been characterized in only a few systems (Howard, 2001;Kress et al, 2007;Moore et al, 2010;Vonna et al, 2007).…”

“…Several bacteria or viruses also hijack filopodia to invade epithelial or endothelial cells (Lehmann et al, 2005;Romero et al, 2011;Schelhaas et al, 2008;Smith et al, 2008;Young et al, 1992). For example, the Yersinia Invasin protein that binds to b1 integrins and the Shigella Type III Secretion System (T3SS) have been shown to interact with and trigger retraction of filopodia (Romero et al, 2011;Vonna et al, 2007;Young et al, 1992).…”

TransKingdom RNA interference: a bacterial approach to challenges in RNAi therapy and delivery

“…In order to facilitate uptake and efficient gene silencing in gastrointestinal cells, these constructs were also engineered to express the invasin gene (Inv) from Yersinia pseudotuberculosis, and the listeriolysin O gene (HlyA) from Listeria monocytogenes. The Inv gene product permits non-invasive E. coli to enter β1-integrin positive colonic epithelial cells (Isberg et al, 1987;Young et al, 1992), whereas the Hly gene product allows the release of genetic material from entry vesicles (Grillot-Courvalin et al, 1998;Mathew et al, 2003). TRIP constructs were then transformed into BL21 DE3 E. coli that express the T7 RNA polymerase necessary for shRNA expression.…”

Surface-modified yeast cells: A novel eukaryotic carrier for oral application

“…The carboxy terminal 192 amino acids of this protein bind to some of the members of the β1-integrin superfamily, while the remainder of the protein is responsible for the presentation of the binding domain on the cell surface [9,10]. Y. enterocolitica possesses a homologue invasin but both proteins are not identical [11].…”