|Truong, Ahn Due|
|Hong, Yeong Ho|
Submitted to: Asian-Australasian Journal of Animal Sciences
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/11/2017
Publication Date: 1/13/2017
Publication URL: http://handle.nal.usda.gov/10113/5832847
Citation: Rengaraj, D., Truong, A., Ban, J., Lillehoj, H.S., Hong, Y. 2017. Distribution and differential expression of microRNAs in the intestinal mucosal layer of necrotic enteritis induced Fayoumi chickens. Asian-Australasian Journal of Animal Sciences. 30(7):1037-1047. Interpretive Summary: Necrotic enteritis (NE) is caused by anaerobic bacteria, Clostridium perfrongens. Incidence of NE has been increasing with the withdrawl of antibiotics growth promoters (AGPs). There is no recombinant vaccines against NE and ability to prevent avian NE will reduce economic cost of more than $ 6 billion. ARS scientists and scientists in South Korean university collaborated in a chicken trial to identify genetic basis for NE disease susceptibility using new generation sequencing technology. In this report, identification of small micro RNA sequences which correlate with broiler NE susceptibility is reported for the first time using various bioinformatics analysis of NE-infected intestinal tissues. The results of this comprehensive bioinformatic analysis clearly showed involvenment of many host genes controlling innate immune response. This new information weill advance our understanding of host genetic factors which influence disease susceptibility in commercial broiler chickens.
Technical Abstract: Despite an increasing number of investigations into the pathophysiology of necrotic enteritis (NE), etiology of NE-associated diseases, and gene expression profiling of NE-affected tissues, the microRNA (miRNA) profiles of NE-affected poultry have been poorly studied. We induced NE disease in the genetically disparate Fayoumi chicken lines (M5.1 and M15.2), and performed non-coding RNA sequencing in the intestinal mucosal layer of both NE-induced and uninfected chickens to examine the differential expression of miRNAs. Total 50 upregulated miRNAs and 26 downregulated miRNAs detected in the NE-induced M5.1 chickens. While 32 upregulated miRNAs and 11 downregulated miRNAs detected in the NE-induced M15.2 chickens. Next, real-time qPCR was performed to further examine four miRNAs (gga-miR-9-5p, gga-miR-20b-5p, gga-miR-196-5p, and gga-let-7d) that showed the highest fold differences. Overall, gga-miR-20b-5p was significantly downregulated in the NE-induced M5.1 chickens and this was associated with the upregulation of its top-ranking target gene, mitogen-activated protein kinase kinase kinase 2. Further bioinformatic analyses revealed that 45 of the gene targets of gga-miR-20b-5p were involved in signal transduction and immune system-related pathways, and 35 of these targets were predicted to interact with each other. Our study is a novel report of miRNA regulation in Fayoumi chickens with experimentally induced NE.