Involvement of CCAAT/enhancer-binding protein in regulation of the rat serine:pyruvate/alanine:glyoxylate aminotransferase gene expression.
In the rat liver, transcription of the serine:pyruvate/alanine:glyoxylate aminotransferase (SPT/AGT) gene occurs from two sites, +1 and +66, in exon 1, resulting in the formation of two mRNAs, one for a precursor of mitochondrial SPT/AGT and the other for peroxisomal SPT/AGT, respectively. In this study, we attempted to characterize the downstream promoter responsible for generation of peroxisomal SPT/AGT. The minimal downstream promoter was confined to the +21-+90 region. We demonstrated that C/EBPalpha and C/EBPbeta bound around the downstream start site (+66) contribute to the promoter activity. The downstream promoter activity is also regulated positively by a short inverted repeat, located 20-30 bp upstream of the downstream start site, through a protein factor(s) bound to this region. On the other hand, the sequence just downstream of the start site may negatively regulate the promoter activity.
Sugiyama
T
T
Department of Internal Medicine III, Hamamatsu University School of Medicine, 1-20-1 Handayama, Hamamatsu, Shizuoka 431-3192, Japan.
Uchida
C
C
Oda
T
T
Kitagawa
M
M
Hayashi
H
H
Ichiyama
A
A
D000818:Animals; D001665:Binding Sites; D022762:CCAAT-Enhancer-Binding Proteins / Q000378:metabolism*; D015971:Gene Expression Regulation, Enzymologic; D017930:Genes, Reporter; D006801:Humans; D011401:Promoter Regions, Genetic; D011485:Protein Binding; D051381:Rats; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012091:Repetitive Sequences, Nucleic Acid; D000637:Transaminases / Q000235:genetics* / Q000378:metabolism; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured
D022762:CCAAT-Enhancer-Binding Proteins; D011993:Recombinant Fusion Proteins; D000637:Transaminases; C019635:Alanine-glyoxylate transaminase; C022638:serine-pyruvate aminotransferase