Regulation of mRNA and miRNA in the response to Salmonella enterica serovar Enteritidis infection in chicken cecum

Abstract

Background Salmonella enterica, serovar Enteritidis (SE) is a food-borne pathogen, which can cause great threat to human health through consumption of the contaminated poultry products. Chicken is the main host of SE. The mRNA and microRNA (miRNA) expression profiles were analyzed on cecum of Shouguang chicken via next-generation sequencing and bioinformatics approaches. The treated group was inoculated SE, and the control group was inoculated with phosphate buffer saline (PBS). Results There were 1760 differentially expressed mRNAs in the SE-infected group, of which 1046 were up-regulated mRNA, and 714 were down-regulated mRNA. In addition, a total of 821 miRNAs were identified, and 174 miRNAs were differentially expressed, of which 100 were up-regulated and 74 were down-regulated. Functional enrichment of differentially expressed mRNAs was similar to miRNA target genes. The functional analysis results of differentially expressed mRNAs and miRNAs were performed. Immune-related processes and KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways were enriched by up-regulated mRNA. The down-regulated mRNAs were enriched in tissue development and metabolic-related KEGG pathways. The functional analysis of up-regulated miRNA target genes was similar to the down-regulated mRNAs. The down-regulated miRNA target genes were enriched in metabolic-related GO (Gene Ontology) -BP (Biological process) terms and KEGG pathways. The overlap of the up-regulated mRNA and the up-regulated miRNA target genes (class I) was 325, and the overlap of the down-regulated miRNA target genes (class II) was 169. The class I enriched in the immune-related GO-BP terms and KEGG pathways. The class II mainly enriched in metabolic-related GO-BP terms and KEGG pathways. Then we detected the expression of mRNA and miRNA through qRT-PCR. The results shown that the expression of HHIP, PGM1, HTR2B, ITGB5, RELN, SFRP1, TCF7L2, SCNN1A, NEK7, miR-20b-5p, miR-1662, miR-15a, miR-16-1-3p was significantly different between two groups. Dual-luciferase reporter assay was used to detect the relationship between miR-20b-5p and SCNN1A. The result indicated that miR-20b-5p regulate immune or metabolic responses after SE infection in Shouguang chickens by directly targeting SCNN1A. Conclusions The findings here contribute to the further analysis of the mechanism of mRNA and miRNA defense against SE infection, and provide a theoretical foundation for the molecular disease-resistant breeding of chickens.

Expression of Toll‐like receptors and host defence peptides in the cecum of chicken challenged with Eimeria tenella

“…These receptors are mainly involved in the recognition of diacylated or triacylated bacterial lipopeptides, 36 and Higuchi et al reported that chTLR2a/chTLR1b heterodimer was activated by peptidoglycan 37 . In the present study, the expression of TLR1a, TLR1b, TLR2a and TLR2b was all significantly upregulated in cecum of the chicken infected with E. tenella , which was consistent with Miao's research of the four chTLRs showed a significant upregulation in the cecum of chickens during infection with S. enterica 38 . These increased gene expression may facilitate an increased recognition of lipoproteins and peptidoglycan.…”

“…37 In the present study, the expression of TLR1a, TLR1b, TLR2a and TLR2b was all significantly upregulated in cecum of the chicken infected with E. tenella, which was consistent with Miao's research of the four chTLRs showed a significant upregulation in the cecum of chickens during infection with S. enterica. 38 These increased gene expression may facilitate an increased recognition of lipoproteins and peptidoglycan.…”