Cytoskeleton rearrangements during Listeria infection: Clathrin and septins as new players in the game

Abstract

The study of an infection process can reveal how microbes exploit the host, and can illuminate unknown host cellular functions. Invasive pathogens have evolved efficient strategies to promote their internalization within normally non-phagocytic host cells. The so-called ''zippering'' bacteria present to host cell receptors molecules that mimic endogenous ligands, thereby inducing specific intracellular signaling cascades ultimately resulting in actin polymerization and uptake. Here we review how the bacterial pathogen Listeria monocytogenes enters into cells, and present a series of studies revealing that in addition to actin rearrangements this bacterium exploits the clathrin-mediated endocytosis machinery together with septins, a novel cytoskeleton element. The challenge is now to decipher how all of these components orchestrate themselves to permit entry into normally non-phagocytic cells. Cell Motil. Cytoskeleton 66: 816-823, 2009. '

Critical Role for the Host GTPase-Activating Protein ARAP2 in InlB-Mediated Entry of Listeria monocytogenes

“…InlB-mediated entry of Listeria requires rearrangements in the F-actin cytoskeleton (8,16,17,29). These cytoskeletal changes are thought to elicit host cell surface changes that drive Listeria engulfment.…”

“…Listeria induces its own internalization (entry) into nonphagocytic mammalian cells, a process that likely plays an important role in traversal of the intestinal, placental, and blood-brain barriers (7,14,16,23). One of the pathways of Listeria entry is mediated by interaction of the bacterial surface protein InlB with its host receptor, the Met receptor tyrosine kinase (16, 37).InlB-Met interaction triggers activation (tyrosine phosphorylation) of the Met receptor and subsequent rearrangements in the F-actin cytoskeleton of the mammalian cell (16,29). These cytoskeletal changes remodel the host cell surface, resulting in engulfment of adherent Listeria.…”

“…InlB-Met interaction triggers activation (tyrosine phosphorylation) of the Met receptor and subsequent rearrangements in the F-actin cytoskeleton of the mammalian cell (16,29). These cytoskeletal changes remodel the host cell surface, resulting in engulfment of adherent Listeria.…”

Regulation of the Actin Cytoskeleton-Plasma Membrane Interplay by Phosphoinositides

“…The local production of PI(3,4,5)P 3 by this kinase is thought to recruit WAVE/N-WASP proteins to the entry site possibly through activation of Rho family GTPases. This activates the Arp/2/3 complex-mediated actin polymerization to drive the internalization of the bacterium (154,259). Interestingly, also many components of the clathrin-mediated endocytosis machinery have been found at the sites of Listeria internalization (376).…”

Role of Kinases and Phosphatases in Host-Pathogen Interactions

“…InlB-Met interaction triggers activation, by tyrosine phosphorylation, of the Met receptor and subsequent rearrangements in the actin cytoskeleton of the mammalian cell (Mostowy & Cossart, 2009). Ultimately, these cytoskeletal changes remodel the host cell surface, resulting in the engulfment of adherent Listeria.…”