title: Genomic identification and molecular characterization of a non-mammalian TNFAIP8L2 gene from Oplegnathus fasciatus.
abstract: Tumor necrosis factor alpha-induced protein 8-like 2 (TNFAIP8L2) is a newly described negative immune regulator, whose enigmatic biological functions are not clearly understood. In the present study, the TNFAIP8L2 homolog of rock bream (Oplegnathus fasciatus) was identified and characterized. The genomic composition of rock bream TNFAIP8L2 (~6.7 kb) represented a tripartite arrangement in which three exons are interrupted by two introns. The rock bream TNFAIP8L2 transcript (1974 bp) possessed a coding sequence of 561 bp encoding a peptide of 186 amino acids. The predicted rock bream TNFAIP8L2 protein was 21.1kDa and revealed the typical features of known TNFAIP8L2 members including the DED-like domain. Rock bream TNFAIP8L2 was composed of six α-helices and demonstrated a distinct folding pattern of the TNFAIP8L2 family. It showed a certain degree of homology and phylogenetic relationship with the corresponding tilapia counterpart. Based on an interspecies genomic organizational comparison of TNFAIP8L2 orthologs, they could be classified into two classes, with teleost and non-teleost origin respectively. While teleost TNFAIP8L2s manifest a tripartite arrangement, non-teleost counterparts demonstrate a dipartite structure suggesting the loss of an intron during the post-piscine speciation. Promoter proximal region of rock bream TNFAIP8L2 consisted of multiple immune responsive cis-regulatory elements. Analysis of basal transcription in eleven tissues revealed its constitutive expression in examined tissues with highest magnitude in the head kidney. The modulated temporal mRNA expression of rock bream TNFAIP8L2 in head kidney post-challenges with stimulants (LPS and poly I:C) and pathogens (Streptococcus iniae and irido virus) was stimulant-specific. Additionally, a drastic down-regulation of rock bream TNFAIP8L2 mRNA level occurred in blood cells collected from experimentally injured animals, and it was accompanied by a contemporaneous down-regulation of cytokines, TNF-α and TGFβ3. All these findings imply that rock bream TNFAIP8L2 is potentially responsible for immune and inflammatory modulation in rock bream.
authors.affiliation: Department of Marine Life Sciences, School of Marine Biomedical Sciences, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea.
authors.forename: Navaneethaiyer
authors.initials: N
authors.lastname: Umasuthan
authors.affiliation: Department of Marine Life Sciences, School of Marine Biomedical Sciences, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea.
authors.forename: Kasthuri Saranya
authors.initials: KS
authors.lastname: Revathy
authors.affiliation: Department of Marine Life Sciences, School of Marine Biomedical Sciences, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea.
authors.forename: Ilson
authors.initials: I
authors.lastname: Whang
authors.affiliation: Graduate School of Medicine, Korea University, Ansan, Gyeonggido 425-707, Republic of Korea.
authors.forename: Eunmi
authors.initials: E
authors.lastname: Kim
authors.affiliation: Department of Aqualife Medicine, Chonnam National University, Chonnam 550-749, Republic of Korea.
authors.forename: Myung-Joo
authors.initials: MJ
authors.lastname: Oh
authors.affiliation: Department of Aqualife Medicine, Chonnam National University, Chonnam 550-749, Republic of Korea.
authors.forename: Sung-Ju
authors.initials: SJ
authors.lastname: Jung
authors.affiliation: Genetics & Breeding Research Center, National Fisheries Research & Development Institute, Geoje 656-842, Republic of Korea.
authors.forename: Jeong-Ho
authors.initials: JH
authors.lastname: Lee
authors.affiliation: Graduate School of Medicine, Korea University, Ansan, Gyeonggido 425-707, Republic of Korea. Electronic address: hcpark67@korea.ac.kr.
authors.forename: Hae-Chul
authors.initials: HC
authors.lastname: Park
authors.affiliation: Department of Marine Life Sciences, School of Marine Biomedical Sciences, Jeju National University, Jeju Self-Governing Province 690-756, Republic of Korea; Marine and Environmental Institute, Jeju National University, Jeju Special Self-Governing Province 690-814, Republic of Korea. Electronic address: jehee@jejunu.ac.kr.
authors.forename: Jehee
authors.initials: J
authors.lastname: Lee
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015536:Down-Regulation; D029941:Fish Proteins / Q000235:genetics*; D005399:Fishes / Q000235:genetics* / Q000276:immunology / Q000382:microbiology; D020869:Gene Expression Profiling; D007249:Inflammation / Q000276:immunology; D047908:Intracellular Signaling Peptides and Proteins / Q000235:genetics*; D008070:Lipopolysaccharides / Q000276:immunology; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic / Q000235:genetics; D017433:Protein Structure, Secondary; D012333:RNA, Messenger / Q000096:biosynthesis; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013290:Streptococcal Infections / Q000276:immunology; D053782:Transforming Growth Factor beta3 / Q000096:biosynthesis / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis / Q000235:genetics / Q000378:metabolism
chemical_list: D029941:Fish Proteins; D047908:Intracellular Signaling Peptides and Proteins; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D053782:Transforming Growth Factor beta3; D014409:Tumor Necrosis Factor-alpha
keywords: Genomic arrangement; Immune/injury challenge; Rock bream; Transcriptional expression; Tumor necrosis factor alpha-induced protein 8-like 2 (TNFAIP8L2)