Molecular cloning and characterization of a ruminant interleukin-6 cDNA.
By hybridization with a human interleukin-6 (IL-6) cDNA fragment a corresponding ruminant (ovine) cDNA was isolated from a lipopolysaccharide (LPS)-stimulated alveolar macrophage library. The nucleotide sequence of the cDNA and the predicted amino acid sequence of the protein showed significant homology to the human and murine molecules. Ovine IL-6 cDNA encodes a polypeptide of 208 amino acids that, based on analysis of human IL-6, is processed to a protein of 180 amino acids. Northern blot analysis and the 7TD1 bioassay were used to analyse regulatory aspects of IL-6 production by primary ovine fibroblasts. Both LPS and recombinant ovine IL-1 alpha were shown to induce IL-6 mRNA with peak levels occurring at 1 h post-stimulation and declining thereafter. When fibroblasts were pretreated with cyclohexamide prior to stimulation the level of induction by LPS and IL-1 alpha increased dramatically and peak levels were observed at 5 h post-stimulation. The level of secreted IL-6 increased rapidly over the first 24 h and continued to increase over the next 48 h.
Andrews
A E
AE
Centre for Animal Biotechnology, School of Veterinary Science, University of Melbourne, Parkville, Victoria, Australia.
Barcham
G J
GJ
Ashman
K
K
Meeusen
E N
EN
Brandon
M R
MR
Nash
A D
AD
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D002417:Cattle; D002478:Cells, Cultured; D003001:Cloning, Molecular; D004247:DNA / Q000032:analysis*; D005347:Fibroblasts; D006801:Humans; D015850:Interleukin-6 / Q000096:biosynthesis / Q000235:genetics*; D008070:Lipopolysaccharides; D016676:Macrophages, Alveolar / Q000276:immunology; D051379:Mice; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D012756:Sheep
D015850:Interleukin-6; D008070:Lipopolysaccharides; D012333:RNA, Messenger; D004247:DNA