Discovery of zebrafish (Danio rerio) interleukin-23 alpha (IL-23α) chain, a subunit important for the formation of IL-23, a cytokine involved in the development of Th17 cells and inflammation

Mol Immunol. 2011 Apr;48(8):981-91. doi: 10.1016/j.molimm.2010.12.012. Epub 2011 Feb 16.


This paper reports the cloning and sequencing of interleukin (IL)-23 p19 subunit for the first time within a non-mammalian species, the zebrafish (Danio rerio), which was discovered using a synteny approach. In addition, amino acid sequences were for IL-23 p19 subunits were also predicted from the stickleback, Fugu and Tetraodon genomes and included in this investigation. The zebrafish IL-23 p19 cDNA consisted of a 66bp 5' UTR, a 249bp 3' UTR and a single open reading frame of 567bp giving a predicted 188 aa IL-23 p19 molecule. Multiple alignment of zebrafish IL-23 p19, with other known IL-23 p19 and IL-12 p35 amino acid sequences revealed areas of amino acid conservation, such as the presence of four predicted α-helixes, cysteines important for disulphide bond formation and the conservation of a tryptophan known to interact with the receptor. Amino acid homologies and phylogenetic analysis confirmed the relationship of the fish IL-23 p19 subunits with their mammalian homologues. All the teleost fish IL-23 p19 subunits were found to have 4 exons and 3 introns similar to that of human and mouse IL-23 p19 and a limited degree of synteny was found between the organisms for the regions containing the IL-23 p19 genes with only PAB-dependent poly(A)-specific ribonuclease subunit 2 (PAN2) and IL-23 p19 found in the same order on human chromosome 12 and all the fish genomes looked at. Lastly using real-time PCR, constitutive expression of IL-12 p40 and IL-23 p19 was observed in the kidney, liver, gut and muscle with IL-12 p40 expression higher than IL-23 p19. As soon as an hour after stimulation with LPS, there was an increase of IL-23 p19 in zebrafish leukocytes and an increase of IL-1β, IL-12 p40 and IL-23 p19 expression was found after infection of zebrafish for 1 or 6 days with Mycobaterium marinum strain E11.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Base Sequence
  • Chromosome Mapping
  • Chromosomes, Human, Pair 12 / genetics
  • Cloning, Molecular
  • Gene Expression Profiling
  • Host-Pathogen Interactions
  • Humans
  • Inflammation Mediators / metabolism*
  • Interleukin-23 Subunit p19 / classification
  • Interleukin-23 Subunit p19 / genetics*
  • Leukocytes / drug effects
  • Leukocytes / metabolism
  • Leukocytes / microbiology
  • Lipopolysaccharides / pharmacology
  • Molecular Sequence Data
  • Mycobacterium marinum / physiology
  • Phylogeny
  • Reverse Transcriptase Polymerase Chain Reaction
  • Sequence Analysis, DNA
  • Sequence Homology, Amino Acid
  • Synteny
  • Th17 Cells / metabolism*
  • Zebrafish / genetics*
  • Zebrafish Proteins / genetics*


  • Inflammation Mediators
  • Interleukin-23 Subunit p19
  • Lipopolysaccharides
  • Zebrafish Proteins

Associated data

  • GENBANK/FN869917