Identification of an enhancer element of class Pi glutathione S-transferase gene required for expression by a co-planar polychlorinated biphenyl.
3,3',4,4',5-Pentachlorobiphenyl (PenCB), one of the most toxic co-planar polychlorinated biphenyl congeners, specifically induces class Pi glutathione S-transferase (GSTP1) as well as cytochrome P-450 1A1 in primary cultured rat liver parenchymal cells [Aoki, Matsumoto and Suzuki (1993) FEBS Lett. 333, 114-118]. However, the 5'-flanking sequence of the GSTP1 gene does not contain a xenobiotic responsive element, to which arylhydrocarbon receptor binds. Using a chloramphenicol acetyltransferase assay we demonstrate here that the enhancer termed GSTP1 enhancer I (GPEI) is necessary for the stimulation by PenCB of GSTP1 gene expression in primary cultured rat liver parenchymal cells. GPEI is already known to contain a dyad of PMA responsive element-like elements oriented palindromically. It is suggested that a novel signal transduction pathway activated by PenCB contributes to the stimulation of GSTP1 expression.
Matsumoto
M
M
Environmental Health Sciences Division, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba 305-0053, Japan. michi@nies.go.jp
Imagawa
M
M
Aoki
Y
Y
D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D015500:Chloramphenicol O-Acetyltransferase / Q000235:genetics; D004247:DNA; D004742:Enhancer Elements, Genetic; D005786:Gene Expression Regulation / Q000187:drug effects*; D051549:Glutathione S-Transferase pi; D005982:Glutathione Transferase / Q000235:genetics*; D007527:Isoenzymes / Q000235:genetics*; D008099:Liver / Q000166:cytology / Q000378:metabolism; D011078:Polychlorinated Biphenyls / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
D007527:Isoenzymes; D004247:DNA; D011078:Polychlorinated Biphenyls; D015500:Chloramphenicol O-Acetyltransferase; D051549:Glutathione S-Transferase pi; D005982:Glutathione Transferase; C496558:Gstp1 protein, rat