Oxidative stress activates metal-responsive transcription factor-1 binding activity. Occupancy in vivo of metal response elements in the metallothionein-I gene promoter.
Oxidative stress (tert-butylhydroquinone) rapidly induced metallothionein-I gene expression in mouse Hepa cells, and this effect was mediated predominantly through metal response promoter elements in transient transfection assays. In vivo genomic footprinting of the mouse metallothionein-I promoter after treatment of Hepa cells with hydrogen peroxide, tert-butylhydroquinone, or zinc suggested a rapid increase in occupancy of the metal response elements. More subtle changes also occurred in the constitutive genomic footprint at the composite major late transcription factor/antioxidant response element. This element may, in part, mediate induction by hydrogen peroxide. Electrophoretic mobility shift assays demonstrated a rapid (30 min) increase in the DNA binding activity of metal-responsive transcription factor-1 in Hepa cells treated with any of these inducers. In control cells, upstream stimulatory factor binding with the major late transcription factor site, and a nuclear protein complex distinct from AP-1, but specific for the antioxidant response element, were detected. The amounts of these complexes were not altered after these treatments. These studies indicate that metal-responsive transcription factor-1 plays a role in activating mouse metallothionein-I gene transcription in response to reactive oxygen species.
Dalton
T P
TP
Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City, Kansas 66160-7421, USA.
Li
Q
Q
Bittel
D
D
Liang
L
L
Andrews
G K
GK
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology; D001483:Base Sequence; D001665:Binding Sites; D002460:Cell Line; D018983:DNA Footprinting; D004268:DNA-Binding Proteins; D004591:Electrophoresis, Polyacrylamide Gel; D005786:Gene Expression Regulation / Q000187:drug effects; D006861:Hydrogen Peroxide / Q000494:pharmacology; D006873:Hydroquinones / Q000494:pharmacology; D008668:Metallothionein / Q000235:genetics*; D051379:Mice; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000378:metabolism; D018808:Transcription Factor AP-1 / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism*; D014158:Transcription, Genetic / Q000187:drug effects; D014162:Transfection; D015032:Zinc / Q000494:pharmacology; D000097809:Transcription Factor MTF-1
D000975:Antioxidants; D004268:DNA-Binding Proteins; D006861:Hydrogen Peroxide; D006873:Hydroquinones; D008668:Metallothionein; D012333:RNA, Messenger; D018808:Transcription Factor AP-1; D014157:Transcription Factors; D015032:Zinc; D000097809:Transcription Factor MTF-1; C018855:2-tert-butylhydroquinone