Positive and negative regulatory elements in the upstream region of the rat Cu/Zn-superoxide dismutase gene.
Cu/Zn-superoxide dismutase (SOD1) catalyses the dismutation of superoxide radicals and neutralizes the oxidative effects of various chemicals. Deletion analysis of the upstream region of the rat SOD1 gene revealed that the promoter contains a positive regulatory element (PRE) and a negative regulatory element (NRE), which encompass the regions from -576 to -412 and from -412 to -305 respectively from the site of initiation of transcription. These DNA elements showed enhancer and silencer activities respectively in the natural context and in a heterologous promoter system. Using an electrophoretic-mobility-shift assay and a supershift assay with a specific antibody, the cis-elements of the PRE and NRE were identified as binding sites for transcription factors Elk1 and YY1 (Ying-Yang 1) respectively. Consistent with the presumed roles of the PRE and NRE, Elk1 increased SOD1 gene transcription about 4-5-fold, whereas YY1 exerted a negative effect of about 6-fold. Mutations of the Elk1- and YY1-binding sites led to diminution and elevation respectively of transcriptional activities, both in the natural context and in heterologous promoter systems. These results suggest that the transcription factors Elk1 and YY1, binding in the PRE and NRE respectively, co-ordinate the expression of the SOD1 gene.
Chang
M S
MS
Department of Molecular Biology and Research Center for Cell Differentiation, Seoul National University, Seoul 151-742, Korea.
Yoo
H Y
HY
Rho
H M
HM
D000818:Animals; D001483:Base Sequence; D001665:Binding Sites; D017931:DNA Primers; D004268:DNA-Binding Proteins / Q000378:metabolism; D050981:Erythroid-Specific DNA-Binding Factors; D006801:Humans; D016297:Mutagenesis, Site-Directed; D015221:Potassium Channels / Q000378:metabolism; D011485:Protein Binding; D011518:Proto-Oncogene Proteins; D051381:Rats; D012045:Regulatory Sequences, Nucleic Acid; D017384:Sequence Deletion; D013482:Superoxide Dismutase / Q000235:genetics*; D014157:Transcription Factors / Q000378:metabolism; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured; D050986:YY1 Transcription Factor; D050807:ets-Domain Protein Elk-1
D017931:DNA Primers; D004268:DNA-Binding Proteins; C494112:ELK1 protein, human; C494114:Elk1 protein, rat; D050981:Erythroid-Specific DNA-Binding Factors; D015221:Potassium Channels; D011518:Proto-Oncogene Proteins; D014157:Transcription Factors; D050986:YY1 Transcription Factor; C494698:YY1 protein, human; C494700:Yy1 protein, rat; D050807:ets-Domain Protein Elk-1; D013482:Superoxide Dismutase