PUBLICATION

Molecular characterization, expression analysis, and biological effects of interleukin-8 in grass carp Ctenopharyngodon idellus

Authors
Wang, T.T., Song, X.H., Bao, G.M., Zhao, L.X., Yu, X., and Zhao, J.
ID
ZDB-PUB-140728-31
Date
2013
Source
Fish & shellfish immunology   35(5): 1421-1432 (Journal)
Registered Authors
Keywords
Gene expression pattern; Grass carp Ctenopharyngodon idellus; Interleukin-8 (IL-8); Phylogenetic analysis; Proinflammatory activity
MeSH Terms
  • Amino Acid Sequence
  • Analysis of Variance
  • Animals
  • Base Sequence
  • Carps/genetics*
  • Carps/immunology
  • Cloning, Molecular
  • Cluster Analysis
  • Computational Biology
  • DNA Primers/genetics
  • DNA, Complementary/genetics
  • Gene Expression Profiling/veterinary
  • Gene Expression Regulation/genetics
  • Gene Expression Regulation/immunology*
  • Interleukin-8/chemistry
  • Interleukin-8/genetics*
  • Interleukin-8/metabolism
  • Models, Molecular*
  • Molecular Sequence Data
  • Phylogeny
  • Protein Conformation*
  • Real-Time Polymerase Chain Reaction/veterinary
  • Sequence Alignment
  • Sequence Analysis, DNA/veterinary
PubMed
23994423 Full text @ Fish Shellfish Immunol.
Abstract
Interleukin-8 (IL-8) is a CXC chemokine that plays key regulatory roles in the immune and inflammatory responses implicated in many human diseases. In this study, we identified and characterized an IL-8 homologue from the grass carp, Ctenopharyngodon idellus. A sequence alignment of the full-length cDNA and genomic DNA showed that the exon/intron organization of grass carp IL-8 (gcIL-8) is identical to those of other known CXC chemokine genes. A multiple alignment analysis showed that gcIL-8 is an ELR(-)CXC chemokine, and its deduced amino acid sequence shares 81% and 36% identity with common carp IL-8s L1 (GenBank ID: ABE47600) and L2 (GenBank ID: AB470924), respectively, suggesting that it belongs to the lineage 1 group of fish IL-8 proteins. On a phylogenetic tree, gcIL-8 clustered with other teleost IL-8 proteins to form a fish-specific clade, clearly distinct from those of bird, mammal, and amphibian proteins. Real-time quantitative PCR analysis indicated that gcIL-8 is differentially expressed in various tissues under normal conditions and that the expression of gcIL-8 mRNA in immune-related tissues is clearly upregulated by Aeromonas hydrophila infection. To explore the biological effects of gcIL-8, we produced a recombinant protein, rgcIL-8, in a prokaryotic expression system. Purified rgcIL-8 was confirmed to be chemoattractive for head kidney neutrophils and mononuclear leukocytes in vitro. Our histopathological study also revealed that rgcIL-8 exerts proinflammatory effects by inducing neutrophil infiltration and erythrocyte extravasation. Overall, these results suggest that IL-8 is crucially involved in the inflammatory responses of fish.
Genes / Markers
Figures
Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping