Cloning and sequencing of cytochrome P450 1A complementary DNA in eel (Anguilla japonica)

Cytochrome P450 1A (CYP1A) complementary DNA was isolated from eel (Anguill a japonica) liver treated with 3-methylcholanthrene. The cDNA contained a 5 ' untranslated region of 163 bp, an open reading flame of 1560 bp coding fo r 519 amino acids and a stop codon, and a 3' untranslated region of 1730 bp . The predicted molecular weight was approximately 58.4 kDa. The deduced am ino acid sequence exhibited identities with reported CYP1A sequences of 80% for rainbow trout, 79% for scup, 76% for plaice and butterfly fish, and 74 % for toadfish. When compared with mammalian CYP proteins, the eel CYP1A wa s more similar to CYP1A1 (54%-56%) than to CYP1A2 (49%-52%). Northern and S outhern blot analyses showed two distinct bands, suggesting the existence o f another 3-methylcholanthrene-inducible CYP1A gene in eel.