Abstract
Host cells use several anti-bacterial pathways to defend against pathogens. Here, using a uropathogenic Escherichia coli (UPEC) infection model, we demonstrate that bacterial infection upregulates RhoB, which subsequently promotes intracellular bacteria clearance by inducing LC3 lipidation and autophagosome formation. RhoB binds with Beclin 1 through its residues at 118 to 140 and the Beclin 1 CCD domain, with RhoB Arg133 being the key binding residue. Binding of RhoB to Beclin 1 enhances the Hsp90-Beclin 1 interaction, preventing Beclin 1 degradation. RhoB also directly interacts with Hsp90, maintaining RhoB levels. UPEC infections increase RhoB, Beclin 1 and LC3 levels in bladder epithelium in vivo, whereas Beclin 1 and LC3 levels as well as UPEC clearance are substantially reduced in RhoB+/- and RhoB-/- mice upon infection. We conclude that when stimulated by UPEC infections, host cells promote UPEC clearance through the RhoB-Beclin 1-HSP90 complex, indicating RhoB may be a useful target when developing UPEC treatment strategies.
Publication types
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Research Support, Non-U.S. Gov't
MeSH terms
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Animals
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Autophagosomes / genetics
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Autophagosomes / metabolism*
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Autophagosomes / ultrastructure
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Beclin-1 / genetics
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Beclin-1 / metabolism*
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Cell Line
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Epithelium / metabolism
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Epithelium / microbiology
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Escherichia coli Infections / genetics
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Escherichia coli Infections / metabolism*
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Escherichia coli Infections / microbiology
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Female
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Gene Knockdown Techniques
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HSP90 Heat-Shock Proteins / genetics
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HSP90 Heat-Shock Proteins / metabolism*
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Humans
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Mice
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Mice, Inbred C57BL
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Mice, Knockout
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Microscopy, Electron, Transmission
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Microtubule-Associated Proteins / metabolism
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Protein Binding
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Protein Stability
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RNA, Small Interfering
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Recombinant Proteins
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Urinary Bladder / metabolism
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Urinary Bladder / microbiology
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Urinary Tract Infections / genetics
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Urinary Tract Infections / metabolism*
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Urinary Tract Infections / microbiology
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Uropathogenic Escherichia coli / growth & development*
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Uropathogenic Escherichia coli / pathogenicity
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rhoB GTP-Binding Protein / genetics
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rhoB GTP-Binding Protein / metabolism*
Substances
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Beclin-1
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HSP90 Heat-Shock Proteins
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MAP1LC3A protein, human
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Microtubule-Associated Proteins
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RNA, Small Interfering
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Recombinant Proteins
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rhoB GTP-Binding Protein