GBPs Inhibit Motility of Shigella flexneri but Are Targeted for Degradation by the Bacterial Ubiquitin Ligase IpaH9.8.

ABSTRACT: Interferon exposure boosts cell-autonomous immunity for more efficient pathogen control. But how interferon-enhanced immunity protects the cytosol against bacteria and how professionally cytosol-dwelling bacteria avoid clearance are insufficiently understood. Here we demonstrate that the interferon-induced GTPase family of guanylate-binding proteins (GBPs) coats Shigella flexneri in a hierarchical manner reliant on GBP1. GBPs inhibit actin-dependent motility and cell-to-cell spread of bacteria but are antagonized by IpaH9.8, a bacterial ubiquitin ligase secreted into the host cytosol. IpaH9.8 ubiquitylates GBP1, GBP2, and GBP4 to cause the proteasome-dependent destruction of existing GBP coats. This ubiquitin coating of Shigella favors the pathogen as it liberates bacteria from GBP encapsu

SUBMITTER: Wandel MP 

PROVIDER: S-EPMC5644667 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature