CHARACTERIZATION OF TYPE 1 INTERFERON RECEPTOR (IFNR1) IN ORANGE-SPOTTED GROUPER (Epinephelus coioides)  

Tang Zhi Zhuang*, Ting-Yu Wang, and Tzong-Yueh Chen
Department of Biotechnology and Bioindustry Sciences, Institute of Biotechnology,
Translational Center for Marine Biotechnology, and Agriculture Biotechnology Research
Center, National Cheng Kung University, Tainan 70101, Taiwan
Email: zhuangtz91@gmail.com

Grouper aquaculture was among known high economic profits in aquaculture industry, raising interests in fish farmers. However, easily outbreak of virus diseases caused huge losses to fish farmers. Mechanism of first line of defense against virus diseases in teleost fish is activated by production of antiviral protein through signaling of secreted cytokine (type I IFN) to neighboring cells. Previous research proved up-regulation of gene expression level of grouper IFN and downstream Mx protein in response to virus infection.

To investigate interaction between type 1 IFN system with nervous necrosis virus infection, full length orange-spotted grouper IFNR1 was firstly cloned and identified as 1444 nucleotides sequence including untranslated region with ORF encoding 433 amino acids. Phylogenetic analysis indicated osgIFNR1 shared high homology similarities with other teleosts. Relative expression of osgIFNR1 was measured according to LPS and Poly I: C treatments which mimic microbial and virus infection respectively in immune organs. Gene expression of osgIFNR1 was up-regulated during 6 hours of poly I: C treatment while LPS treatment showed highest expression level during 12 hours post-stimulation. The present study provides insight of cloning and identification of full length osgIFNR1 follow by real-time PCR gene expression analysis showed effect of IFNR1 through up-regulation of gene expression level during 6 hours of poly I: C treatment. This study summarizes first analysis of orange-spotted grouper IFNR role in type 1 interferon system against nodavirus infection.