MiR-155 induction by microbes/microbial ligands requires NF-κB-dependent de novo protein synthesis.
MiR-155 regulates numerous aspects of innate and adaptive immune function. This miR is induced in response to Toll-like receptor ligands, cytokines, and microbial infection. We have previously shown that miR-155 is induced in monocytes/macrophages infected with Francisella tularensis and suppresses expression of the inositol phosphatase SHIP to enhance activation of the PI3K/Akt pathway, which in turn promotes favorable responses for the host. Here we examined how miR-155 expression is regulated during infection. First, our data demonstrate that miR-155 can be induced through soluble factors of bacterial origin and not the host. Second, miR-155 induction is not a direct effect of infection and it requires NF-κB signaling to up-regulate fos/jun transcription factors. Finally, we demonstrate that the requirement for NF-κB-dependent de novo protein synthesis is globally shared by microbial ligands and live bacteria. This study provides new insight into the complex regulation of miR-155 during microbial infection.
Molecular, Cellular, and Developmental Biology Program, The Ohio State University Columbus, OH, USA.
Thomas J
TJ
Cremer
Kavin
K
Fatehchand
Prexy
P
Shah
Devyn
D
Gillette
Hemal
H
Patel
Rachel L
RL
Marsh
Beth Y
BY
Besecker
Murugesan V S
MV
Rajaram
Estelle
E
Cormet-Boyaka
Thirumala-Devi
TD
Kanneganti
Larry S
LS
Schlesinger
Jonathan P
JP
Butchar
Susheela
S
Tridandapani
D002478:Cells, Cultured; D005604:Francisella tularensis / Q000276:immunology*; D006801:Humans; D035683:MicroRNAs / Q000096:biosynthesis*; D009000:Monocytes / Q000276:immunology*; D016328:NF-kappa B / Q000378:metabolism*; D014176:Protein Biosynthesis
C524942:MIRN155 microRNA, human; D035683:MicroRNAs; D016328:NF-kappa B