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Biologie cellulaire de l'infection par <i>Listeria monocytogenes</i>

Entry of L. monocytogenes via the InlB/Met interaction.

J. Pizarro-Cerda et al. (2010) Bioessays 32:496-504 Entry of L. monocytogenes via the InlB/Met interaction. (A) The bacterial surface protein InlB can interact through its C-terminal domain with the gC1q-R protein and with extracellular glycosaminoglycans (GAGs), but it is the binding of the tyrosine receptor kinase Met by the InlB N-terminal domain that efficiently triggers bacterial internalization. (B) Activation of Met leads to its autophosphorylation and recruitment/phosphorylation of Cbl, an ubiquitin ligase required for Met ubiquitination. (C) Ubiquitinated Met promotes the recruitment to the bacterial entry site of the clathrin endocytic machinery. Other protein adaptors recruited by Met, including Gab1, Shc, Grb2, activate the type I PI 3-kinase p85/ p110 for the production of PIP3 within cholesterol-rich domains, which in turn is involved in the activation of Rac and/or Cdc42 (depending on the cell type), activation of Wave and/or N-Wasp, and Arp2/3 for actin polymerization. Dynamin, which is recruited by the endocytosis machinery to the bacterial entry site, can interact with cortactin, which in turn can participate to the activation of the Arp2/3 complex and actin polymerization. The LIM kinase controls the phosphorylation state of cofilin to regulate actin depolymerization. (D) Interactions between clathrin and polymerizing actin triggers the invagination of the bacteria in a partially clathrin-coated compartment.