Characterisation and expression analysis of an interleukin 6 homologue in the Japanese pufferfish, Fugu rubripes.
The first IL-6 sequence in fish has been determined in Fugu rubripes by exploiting the synteny that is found between some regions of the human and Fugu genomes. The predicted 227 aa IL-6 homologue contains the IL-6/G-CSF/MGF motif, has a predicted secondary structure of four alpha-helixes but only contains two of the four cysteines important in disulphide bond formation. It shows low amino acid identities (20-29%) with known IL-6 sequences, although phylogenetic analysis groups the Fugu molecule with the other IL-6 molecules. The gene organisation of Fugu IL-6 and the level of synteny between the human and Fugu genomes has been well conserved during evolution with the order and orientation of the genes matching exactly to human chromosome 7. PHA stimulation of Fugu kidney cells resulted in a large increase in the Fugu IL-6 transcript, whereas LPS and Poly I:C resulted in a significant increase within spleen cells. The discovery of IL-6 in fish will now allow more detailed investigations of local inflammatory responses.
Bird
Steve
S
Department of Zoology, Scottish Fish Immunology Research Centre, School of Biological Sciences, University of Aberdeen, Tillydrone Avenue, Aberdeen AB24 2TZ, UK.
Zou
Jun
J
Savan
Ram
R
Kono
Tomoya
T
Sakai
Masahiro
M
Woo
Janet
J
Secombes
Chris
C
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002874:Chromosome Mapping; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics; D029941:Fish Proteins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology*; D015870:Gene Expression; D006801:Humans; D015850:Interleukin-6 / Q000737:chemistry / Q000235:genetics*; D008969:Molecular Sequence Data; D010802:Phylogeny; D017433:Protein Structure, Secondary; D017386:Sequence Homology, Amino Acid; D023741:Takifugu / Q000235:genetics* / Q000276:immunology*
D018076:DNA, Complementary; D029941:Fish Proteins; D015850:Interleukin-6