The functional characterisation of CK-1, a putative CC chemokine from rainbow trout (Oncorhynchus mykiss).
Recently a number of cytokine homologs have been cloned in teleost fish, including several that resemble chemokines, but to date few have been confirmed using functional assays. Chemokines are a family of cytokines that are able to induce chemotaxis in leucocytes. In this study CK-1, a rainbow trout chemokine, was functionally characterised. Recombinant CK-1 is able to attract rainbow trout peripheral blood leucocytes (PBL) in a micro-chemotaxis chamber. A greater number of PBLs migrated in response to CK-1 than to negative controls, either media alone or equivalent concentrations of beta2M, while comparable numbers migrated to the positive control, recombinant human C5a. The tissue distribution of CK-1 mRNA was also assessed by Northern blotting of RT-PCR and showed that expression is constitutive in the liver and gut, and is inducible by intraperitoneal injection of phytohemagglutinin in PBL and the head-kidney. Continuous cell lines generated from the gut and pituitary gland of the rainbow trout also express CK-1 message, whilst Southern analysis shows that CK-1 is a single copy gene. Finally, CK-1 shows the greatest amino acid similarity CCL20/LARC/Mip-3alpha as well as similar gene structure and expression pattern.
Lally
James
J
Department of Biology, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada.
Al-Anouti
Fatme
F
Bols
Niels
N
Dixon
Brian
B
D000818:Animals; D015152:Blotting, Northern; D015139:Blotting, Southern; D018925:Chemokines / Q000235:genetics / Q000502:physiology*; D002633:Chemotaxis / Q000502:physiology*; D016000:Cluster Analysis; D017931:DNA Primers; D029941:Fish Proteins / Q000235:genetics / Q000502:physiology*; D007962:Leukocytes / Q000502:physiology*; D017686:Oncorhynchus mykiss / Q000276:immunology* / Q000378:metabolism* / Q000502:physiology; D010802:Phylogeny; D010835:Phytohemagglutinins / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
C118286:CK-1 protein, Oncorhynchus mykiss; D018925:Chemokines; D017931:DNA Primers; D029941:Fish Proteins; D010835:Phytohemagglutinins