Transcriptional regulation of the pyruvate kinase erythroid-specific promoter.
Mammal pyruvate kinases are encoded by two genes. The L gene produces the erythroid (R-PK) or the hepatic (L-PK) isozymes by the alternative use of two promoters. We report the characterization of the cis- and trans-acting elements involved in the tissue-specific activity of the L gene erythroid promoter. A R-PK DNA fragment extending from -870 to +54 relative to the cap site confers erythroid specificity to a reporter gene. Within this region, we define a minimal promoter (-62 to +54) that displays erythroid-specific activity and contains two DNA binding sites. One, located at -50, binds members of the CCACC/Sp1 family and the other, located at -20, binds the erythroid factor GATA-1. Although the -20 GATA binding site (AGATAA) is also a potential TFIID binding site, it does not bind TFIID. Furthermore, the substitution of this GATA binding site by a canonical TFIID binding site suppresses the promoter activity. Mutations and deletions of both sites indicate that only the association of CCACC/Sp1 and GATA binding sites can drive efficient and tissue-specific expression of this R-PK minimal promoter. Finally, by co-transfection experiments, we study the elements involved in the hGATA-1 transactivation of the R-PK promoter in HeLa cells.
Max-Audit
I
I
Institut National de la Santé et de la Recherche Médicale U.91, Hôpital Henri Mondor, Créteil, France.
Eleouet
J F
JF
Roméo
P H
PH
D000328:Adult; D001483:Base Sequence; D001665:Binding Sites; D004247:DNA / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D004912:Erythrocytes / Q000378:metabolism*; D050981:Erythroid-Specific DNA-Binding Factors; D005260:Female; D050982:GATA1 Transcription Factor; D006367:HeLa Cells; D006801:Humans; D004915:Leukemia, Erythroblastic, Acute; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D011401:Promoter Regions, Genetic; D011770:Pyruvate Kinase / Q000235:genetics*; D017384:Sequence Deletion; D035362:Transcription Factor TFIID; D014157:Transcription Factors / Q000378:metabolism; D014158:Transcription, Genetic; D015533:Transcriptional Activation; D014407:Tumor Cells, Cultured; D016335:Zinc Fingers
D004268:DNA-Binding Proteins; D050981:Erythroid-Specific DNA-Binding Factors; D050982:GATA1 Transcription Factor; C494688:GATA1 protein, human; D035362:Transcription Factor TFIID; D014157:Transcription Factors; D004247:DNA; D011770:Pyruvate Kinase