Citrobacter rodentiumalters the mouse colonic miRNome

Citrobacter rodentiumis a murine pathogen causing transmissible colonic hyperplasia and colitis with a pathogenic mechanism similar to foodborne enterohaemorrhagic Escherichia coliin humans. Mechanisms underlying intestinal responses to C. rodentiuminfection are incompletely understood. We identified 24 colonic microRNAs (miRNAs) as significantly deregulated in response to C. rodentium, including miR-7a, -17, -19a, -20a, -20b, -92a, -106a, -132, -200a, and -2137; most of these miRNAs belong to the oncogenic miR-17-92 clusters. Pathways involved in cell cycle, cancers, and immune responses were enriched among the predicted targets of these miRNAs. We further demonstrated that an apoptosis facilitator, Bim, is a candidate gene target of miRNA-mediated host response to the infection. These findings suggest that host miRNAs participate in C. rodentiumpathogenesis and may represent novel treatment targets.