Atlantic salmon interferon genes: cloning, sequence analysis, expression, and biological activity.
In this work, we report cDNA cloning of two type I interferons (IFNs) from the head kidney of Atlantic salmon, called SasaIFN-alpha1 (829 bp) and SasaIFN-alpha2 (1290 bp). Both translate into 175 amino acid precursor molecules showing 95% amino acid sequence identity. The precursors have a putative 23 amino acid signal peptide, which suggests that the mature Atlantic salmon IFNs contain 152 amino acids (18.2 kDa). Salmon IFN appears to have five alpha-helices, similar to mammalian and avian type I IFNs, and showed 45% sequence identity with zebrafish IFN, up to 29% identity with mammalian IFN-alpha sequences, and 17%-18% sequence identity with mammalian IFN-beta and chicken type I IFNs. Human embryonic kidney 293 cells transfected with the SasaIFN-alpha1 cDNA gene produced high titers of acid-stable antiviral activity, which protected salmonid cells against infectious pancreatic necrosis virus (IPNV) and also induced Mx protein in the cells. Poly(I)-poly(C) induced two IFN transcripts in head kidney of Atlantic salmon. Genomic IFN sequences contained four introns and five exons, which is different from the intronless type I IFN genes of birds and mammals.
Department of Marine Biotechnology, Norwegian College of Fishery Science, University of Tromsø, N-9037 Tromsø, Norway. borrer@nfh.uit.no
Børre
B
Robertsen
Veronica
V
Bergan
Torunn
T
Røkenes
Rannveig
R
Larsen
Artur
A
Albuquerque
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D003001:Cloning, Molecular; D017077:Culture Media, Conditioned / Q000737:chemistry / Q000494:pharmacology; D018076:DNA, Complementary / Q000235:genetics; D029941:Fish Proteins / Q000737:chemistry / Q000235:genetics*; D019204:GTP-Binding Proteins / Q000378:metabolism; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation / Q000187:drug effects; D023281:Genomics; D006801:Humans; D007372:Interferons / Q000737:chemistry / Q000235:genetics*; D007438:Introns / Q000235:genetics; D007668:Kidney / Q000378:metabolism; D008969:Molecular Sequence Data; D064547:Myxovirus Resistance Proteins; D010802:Phylogeny; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020317:Salmo salar / Q000235:genetics*; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid
D017077:Culture Media, Conditioned; D018076:DNA, Complementary; D029941:Fish Proteins; D064547:Myxovirus Resistance Proteins; D012333:RNA, Messenger; D007372:Interferons; D019204:GTP-Binding Proteins