Bela-Ong, Dennis

Lorenzen, Niels

Schyth, Brian Dall

The fish rhabdovirus Viral hemorrhagic septicemia virus (VHSV) causes severe disease in farmed rainbow trout (Oncorhynchus mykiss). The potential threat from wildlife marine reservoir of VHSV, particularly to sea-farmed fish demands disease protection measures. Identification of biomarkers during infection is important to understand the complex web of interactions involved in the underlying host immune response, which is a requisite to developing effective disease control strategies. MicroRNAs potently mediate post-transcriptional silencing of a broad range of genes by the RNA interference mechanism and have been shown to regulate cellular processes, including immune responses. A microarray experiment in our lab revealed that a number of miRNAs were upregulated in fish liver following VHSV infection. Here, we validated the expression of the miRNAs and analyzed for associated expression of interferon (IFN)-related genes in the liver of VHSV-infected fish. Quantitative RT-PCR verified positive regulation for most of the miRNAs shown to be upregulated by our microarray analysis. Of these, miR-155, miR-462, and miR-731 had the highest expression levels. The increased expression of these miRNAs in infected liver correlated with the upregulation of type I IFN and the type I IFN-inducible Mx and Vig-1 genes, as well as that of IFN-gamma, indicating activation of both general anti-viral IFN response and natural killer cell and/or T cell responses. Further analysis of the expression of the three most highly upregulated miRNAs in fish intramuscularly injected with a type I IFN construct and the general IFN stimulator and TLR-3 agonist, poly I:C showed increased expression of miR-155, miR-462, and miR-731, as well as Mx at the site of injection relative to controls. This suggests that the increased levels of the three miRNAs at the site of administration is associated with type I interferons, which besides their anti-viral effects are known to have major immune regulatory roles in mammals. Besides adding to our understanding of anti-viral immunity, response profiles of miRNAs could serve as molecular signatures of responses to infection. In the future we plan to analyze whether individual variability is associated with differences in disease susceptibility

Online Research Database In Technology

                       General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.  • Users may download and print one copy of any publication from the public portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal   If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim.     Downloaded from orbit.dtu.dk on: Dec 20, 2017Expression of microRNAs and interferon-related genes in rainbow trout(Oncorhynchus mykiss Walbaum) infected with Viral hemorrhagic septicemia virusBela-Ong, Dennis; Schyth, Brian Dall; Lorenzen, NielsPublication date:2012Link back to DTU OrbitCitation (APA):Bela-Ong, D., Schyth, B. D., & Lorenzen, N. (2012). Expression of microRNAs and interferon-related genes inrainbow trout (Oncorhynchus mykiss Walbaum) infected with Viral hemorrhagic septicemia virus. Abstract fromInternational Workshop on Small RNAs in Cancer, Inflammation, and Aging, Copenhagen, Denmark.EXPRESSION OF MICRORNAS AND INTERFERON RELATED GENES IN RAINBOW TROUT ONCORHYNCHUS MYKISS (WALBAUM, 1792) INFECTED WITH VIRAL HEMORRHAGIC SEPTICEMIA VIRUS  Dennis B. Bela-ong*, Brian Dall Schyth, and Niels Lorenzen  Department of Poultry, Fish, and Fur Animals, National Veterinary Institute, Technical University of Denmark, Hangøvej 2, DK-8200 Århus N, DENMARK  *Corresponding author: Tel: +45 35886814 Fax: +45 35886901 Email: debo@vet.dtu.dk            The fish rhabdovirus Viral hemorrhagic septicemia virus (VHSV) causes severe disease in farmed rainbow trout (Oncorhynchus mykiss). The potential threat from wildlife marine reservoir of VHSV, particularly to sea-farmed fish demands disease protection measures. Identification of biomarkers during infection is important to understand the complex web of interactions involved in the underlying host immune response, which is a requisite to developing effective disease control strategies. MicroRNAs potently mediate post-transcriptional silencing of a broad range of genes by the RNA interference mechanism and have been shown to regulate cellular processes, including immune responses. A microarray experiment in our lab revealed that a number of miRNAs were upregulated in fish liver following VHSV infection. Here, we validated the expression of the miRNAs and analyzed for associated expression of interferon (IFN)-related genes in the liver of VHSV-infected fish. Quantitative RT-PCR verified positive regulation for most of the miRNAs shown to be upregulated by our microarray analysis. Of these, miR-155, miR-462, and miR-731 had the highest expression levels. The increased expression of these miRNAs in infected liver correlated with the upregulation of type I IFN and the type I IFN-inducible Mx and Vig-1 genes, as well as that of IFN-gamma, indicating activation of both general anti-viral IFN response and natural killer cell and/or T cell responses. Further analysis of the expression of the three most highly upregulated miRNAs in fish intramuscularly injected with a type I IFN construct and the general IFN stimulator and TLR-3 agonist, poly I:C showed increased expression of miR-155, miR-462, and miR-731, as well as Mx at the site of injection relative to controls. This suggests that the increased levels of the three miRNAs at the site of administration is associated with type I interferons, which besides their anti-viral effects are known to have major immune regulatory roles in mammals. Besides adding to our understanding of anti-viral immunity, response profiles of miRNAs could serve as molecular signatures of responses to infection. In the future we plan to analyze whether individual variability is associated with differences in disease susceptibility.    Email: Dennis Bela-ong (debo@vet.dtu.dk); Brian Dall Schyth (bdsc@vet.dtu.dk); Niels Lorenzen (nilo@vet.dtu.dk)   Keywords: microRNA, Viral hemorrhagic septicemia virus (VHSV), interferon, rainbow trout 

Expression of microRNAs and interferon-related genes in rainbow trout (Oncorhynchus mykiss Walbaum) infected with Viral hemorrhagic septicemia virus

http://orbit.dtu.dk/ws/files/52563141/DBELA_ONG.pdf

Expression of microRNAs and interferon-related genes in rainbow trout (Oncorhynchus mykiss Walbaum) infected with Viral hemorrhagic septicemia virus

Abstract

Similar works

Full text

Available Versions

Online Research Database In Technology