title: Identification of a retinoic acid-inducible gene I from Japanese eel (Anguilla japonica) and expression analysis in vivo and in vitro.
abstract: RIG-I (retinoic acid inducible gene-I) is one of the key cytosolic pattern recognition receptors (PRRs) for the recognition of cytosolic viral nucleic acids and the production of type I interferons (IFNs). The full-length cDNA sequence of RIG-I (AjRIG-I) in Japanese eel (Anguilla japonica) was identified and characterized in this article. The full-length cDNA of AjRIG-I was 3468 bp, including a 5'-untranslated region (UTR) of 52 bp, a 3'-UTR of 617 bp and an open reading frame (ORF) of 2799 bp encoding a polypeptide of 933 amino acid residues with a calculated molecular mass of 106.2 kDa. NCBI CDD analysis showed that the AjRIG-I protein had the typical conserved domains, including two adjacent caspase activation and recruitment domains (CARDs), a DEXDc domain, a HELICc domain and a C-terminal regulatory domain (RD). Quantitative real-time polymerase chain reaction (qRT-PCR) analysis revealed a broad expression for AjRIG-I in a wide range of tissues, with the predominant expression in liver, followed by the gills, spleen, kidney, intestine, skin, and the very low expression in muscle and heart. The AjRIG-I expressions in liver, spleen and kidney were significantly induced following injection with LPS, the viral mimic poly I:C, and Aeromonas hydrophila infection. In vitro, the AjRIG-I transcripts of Japanese eel liver cells were significantly enhanced by poly I:C and PGN stimulation, down-regulated with CpG-DNA treatment whereas no change of the expression level was found post LPS challenge. These results collectively suggested AjRIG-I transcripts expression possibly play an important role in fish defense against viral and bacterial infection.
authors.affiliation: College of Fisheries, Jimei University, Xiamen, 361021, Fujian Province, China; Engineer Research Center of Eel Modern Industry Technology, Ministry of Education, China; Key Laboratory of Healthy Mariculture for the East China Sea, Ministry of Agriculture, China. Electronic address: 2394417698@qq.com.
authors.forename: Jianjun
authors.initials: J
authors.lastname: Feng
authors.affiliation: College of Fisheries, Jimei University, Xiamen, 361021, Fujian Province, China; Engineer Research Center of Eel Modern Industry Technology, Ministry of Education, China; Key Laboratory of Healthy Mariculture for the East China Sea, Ministry of Agriculture, China.
authors.forename: Songlin
authors.initials: S
authors.lastname: Guo
authors.affiliation: College of Fisheries, Jimei University, Xiamen, 361021, Fujian Province, China; Engineer Research Center of Eel Modern Industry Technology, Ministry of Education, China; Key Laboratory of Healthy Mariculture for the East China Sea, Ministry of Agriculture, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Lin
authors.affiliation: College of Fisheries, Jimei University, Xiamen, 361021, Fujian Province, China; Engineer Research Center of Eel Modern Industry Technology, Ministry of Education, China; Key Laboratory of Healthy Mariculture for the East China Sea, Ministry of Agriculture, China.
authors.forename: Yilei
authors.initials: Y
authors.lastname: Wang
authors.affiliation: College of Animal Science, Fujian Agriculture and Forestry University, Fuzhou, 350002, China.
authors.forename: Ziping
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: College of Fisheries, Jimei University, Xiamen, 361021, Fujian Province, China; Engineer Research Center of Eel Modern Industry Technology, Ministry of Education, China; Key Laboratory of Healthy Mariculture for the East China Sea, Ministry of Agriculture, China.
authors.forename: Zaipeng
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: College of Fisheries, Jimei University, Xiamen, 361021, Fujian Province, China; Engineer Research Center of Eel Modern Industry Technology, Ministry of Education, China; Key Laboratory of Healthy Mariculture for the East China Sea, Ministry of Agriculture, China.
authors.forename: Lili
authors.initials: L
authors.lastname: Yu
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology; D016980:Aeromonas hydrophila / Q000502:physiology; D000595:Amino Acid Sequence; D000811:Anguilla; D000818:Animals; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics / Q000378:metabolism; D005393:Fish Diseases / Q000235:genetics* / Q000276:immunology / Q000382:microbiology; D029941:Fish Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D005786:Gene Expression Regulation / Q000187:drug effects; D016905:Gram-Negative Bacterial Infections / Q000235:genetics / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D008070:Lipopolysaccharides / Q000494:pharmacology; D009928:Organ Specificity; D011070:Poly I-C / Q000494:pharmacology; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D016415:Sequence Alignment / Q000662:veterinary
chemical_list: D000276:Adjuvants, Immunologic; D018076:DNA, Complementary; D029941:Fish Proteins; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D011070:Poly I-C
keywords: Anguilla japonica; PAMPs challenge; Retinoic acid-inducible gene I; cDNA; mRNA expression