CDNA CLONING OF A 8-LIPOXYGENASE AND A NOVEL EPIDERMIS-TYPE LIPOXYGENASE FROM PHORBOL ESTER-TREATED MOUSE SKIN

Using a combination of PCR cloning and conventional screening procedur es, we isolated from phorbol ester-treated mouse epidermis two full le ngth cDNA clones encoding novel lipoxygenases. One of the cDNAs turned out to be identical to the recently cloned 8-lipoxygenase [Jisaka et al., J. Biol. Chem. 272 (1997) 24410-24416], the open reading frame of the second one corresponded to a protein of 701 amino acids with a ca lculated molecular mass of 80.6 kDa. The amino acid sequence showed 50 .8% identity to human 15-lipoxygenase 2, approximately 40% to 5-lipoxy genase and 35% to 12- and 15-lipoxygenases, A unique structural featur e is the insertion of 31 amino acid residues in the amino-terminal par t of the molecule. Based on these data, we conclude that this epidermi s-derived cDNA encodes a novel lipoxygenase isoform termed provisional ly epidermis-type lipoxygenase 2 (e-LOX 2). (C) 1998 Elsevier Science B.V.