Modulation of porcine microRNAs associated with apoptosis and NF-κB signaling pathways in response to Salmonella enterica serovar Typhimurium.

MicroRNAs (miRNAs) are small, non-coding RNAs that regulate eukaryotic gene expression at the post-transcriptional level. In addition to their involvement in a variety of biological processes, miRNAs are implicated in the eukaryotic response to bacterial pathogens. The objective of this study was to identify miRNAs involved in the regulation of the porcine response to the human foodborne pathogen, Salmonella enterica serovar Typhimurium (S. Typhimurium). Differential expression analysis from the whole blood of pigs over a 7-day period following S. Typhimurium challenge identified 50 miRNAs, many of which are implicated in functional pathways associated with NF-κB signaling and apoptosis (e.g., ssc-let-7c, ssc-miR-21). Transcriptional analyses of whole blood mRNA identified the differential expression of several genes involved in NF-κB signaling and apoptosis (e.g., IL10, CBX4, TGFB2) whose mRNAs are predicted targets of miRNAs identified in our study. Overall, our data identified porcine miRNAs that are differentially expressed following S. Typhimurium challenge, thereby defining regulatory factors to target for controlling the porcine response to this human foodborne pathogen.