MOLECULAR-CLONING OF A PHTHALATE-INDUCIBLE CYP4 GENE (CYP4T2) IN KIDNEY FROM THE SEA BASS, DICENTRARCHUS-LABRAX

A fall-length cDNA sequence was isolated from kidney total RNA of di(2 -ethylhexyl) phthalate-treated sea bass by reverse-transcriptase polym erase chain reaction; and then rapid amplification of cDNA ends. The d educed amino acid sequence, which has been named CYP4T2, shared 69 and 54.4% amino acid identity with rainbow trout CYP4T1 and rat CYP4B1, r espectively. RNA blot analysis using the CYP4T2 cDNA as a probe indica ted that the mRNA was rather abundant in kidney, and less so in liver, small intestine, and brain. Treatment of sea bass with peroxisome pro liferators showed marked tissue-specific induction. CYP4 inducers clof ibrate, di(2-ethylhexyl) phthalate (DEHP), and 2,4-dichlorophenoxy ace tic acid (2,4-D) were administered by intraperitoneal injection. The s trongest induction was found in kidney after a DEHP treatment (6.5-fol d) or a 2,4-D treatment (9-fold), while no induction was observed in l iver. (C) 1998 Academic Press.