Comparison of microRNA Profiles between Bovine Mammary Glands Infected with Staphylococcus aureus and Escherichia coli

Abstract

MicroRNAs (miRNAs) play crucial roles in regulating innate and adaptive immunity in humans and animals. Infection with E. coli or S. aureus can cause inflammation of the mammary glands, which results in significant economic losses in dairy cattle. However, the regulatory mechanisms of miRNAs in response to E. coli or S. aureus infection in bovine mammary glands have not been thoroughly explored. To discover the differential expression of miRNA in bovine mammary gland challenged with E. coli or S. aureus, we performed miRNA sequencing on tissue samples. A total of 1838 miRNAs were identified, including 580 known-miRNAs (included in the miRbase database) and 1258 predicted novel miRNAs. The miRNA expression patterns indicated that, compared with control samples, 279 miRNAs and 305 miRNAs were differentially expressed miRNAs (DIE-miRNA) in S. aureus and E. coli infected tissues, respectively. Moreover, the results of comparison the DIE-miRNAs between the E. coli and S. aureus infected groups showed that 197 DIE-miRNAs are identical, 108 DIE-miRNAs are specific to the E. coli group, and 82 DIE-miRNAs are specific to the S. aureus group. Many DIE-miRNAs, such as bta-miR-144, bta-miR-451 and bta-miR-7863, might be the useful biomarkers of mastitis caused by E. coli and S. aureus. In addition, target genes of the DIE-miRNAs were predicted. The Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis indicated that these DIE-miRNAs are likely involved in many immune signaling pathways, including the Toll-like receptor signaling pathways, MAPK signaling pathway, cell adhesion molecules, TGF-β signaling pathway, leukocyte trans endothelial migration, cytokine-cytokine receptor interaction, and chemokine signaling pathways. This study has provided supportive evidence that miRNAs may serve as diagnostic biomarkers of mastitis in dairy cows, and suggests potentially of effective strategies to combat mastitis.

Expression profiling of peripheral blood miRNA using RNAseq technology in dairy cows with Escherichia coli-induced mastitis

“…coli and S . aureus -infected mammary tissues and the results show that there are multiple differentially expressed miRNAs in infected mammary tissues 10 , 22 , 23 .…”

“…Experimental animals and methods used for the induction and verification of mastitis models have been previously described 22 . In brief, healthy 2-year-old half-sibling dairy cows were divided into control and experimental groups.…”

“…Based on protocols from previous publications 22 , 40 , 41 , 1.5 μg of qualified RNA was taken and a small RNA library was constructed using the method described in the NEBNext® Ultra™ Small RNA Sample Library Prep Kit for Illumina® (NEB, USA). After the library was constructed, the library concentration was tested using Qubit 2.0 and was adjusted to 1 ng/μl.…”

Milk MicroRNAs in Health and Disease

“…A comparison of milk microRNA contents with mammary gland cell profiles by small RNA sequencing (Hou et al., ; Ju et al., ; Li et al., ; Luoreng, Wang, Mei, & Zan, ; Shen et al., ) supports the epithelial origin of these microRNAs because the most enriched microRNAs in milk are also highly enriched in mammary glands cells and are of high importance for lactation (Chen et al., ; Do et al., , ; Gu et al., ; Muroya et al., ).…”

Stability and profiling of urinary microRNAs in healthy cats and cats with pyelonephritis or other urological conditions

“…Likewise, in the cluster analyses, the cat with E. coli ‐associated SB, but not the cat with Staphylococcus ‐associated PN, clustered along with the E. coli ‐associated PN group. Pathogen‐specific differential expression of miRNAs has been detected in other infections, such as bovine mastitis caused by E. coli and Staphylococcus aureus and likely involves multiple immunological reactions including toll‐like receptor (TLR) signaling pathways. The underlying pathophysiological explanation to miR‐16 upregulation in our study remains obscure.…”