Characterization of the 5'-flanking region of the human transcription factor Sp3 gene.
A fragment of 1079 bp from the 5'-flanking region of the human Sp3 gene was isolated and characterized. The Sp3 promoter is a GC-rich region that contains putative binding sites for Elk-1, c-Myb, NF-1, Ap1, Sp1, NF-Y, Ap2 and USF. Several transcriptional start sites located between 70 and 132 bp upstream of the translational start site were identified. The proximal promoter was contained in the first 281 bp 5' of the translational start, whereas the region including up to -225 relative to the translational start was referred as the minimal promoter. Transient transfections and luciferase assays revealed activation of the Sp3 proximal promoter upon overexpression of either Sp1 or Sp3, alone or in combination. Gel-shift and supershift assays demonstrated specific binding of Sp1 and Sp3 proteins to the GC box located in the proximal promoter of Sp3. Overexpression of NF-YA had a synergistic effect on Sp1 overexpression and an additive effect on Sp3 overexpression. Additionally, overexpression of NF-YA, Sp1 and Sp3 altogether had a synergistic effect on Sp3 promoter activity. Furthermore, binding of the NF-Y complex to the CCAAT box located in the proximal promoter of Sp3 was observed in gel-shift assays.
Tapias
Alicia
A
Department of Biochemistry and Molecular Biology, School of Pharmacy, University of Barcelona, Avenue Diagonal 643, Barcelona E-08028, Spain.
Monasterio
Paloma
P
Ciudad
Carlos J
CJ
Noé
Véronique
V
D024506:5' Flanking Region / Q000235:genetics*; D000595:Amino Acid Sequence; D001483:Base Sequence; D023081:CCAAT-Binding Factor / Q000502:physiology; D003001:Cloning, Molecular; D004268:DNA-Binding Proteins / Q000235:genetics*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006367:HeLa Cells; D006801:Humans; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D012689:Sequence Homology, Nucleic Acid; D016329:Sp1 Transcription Factor / Q000502:physiology; D051705:Sp3 Transcription Factor; D014157:Transcription Factors / Q000235:genetics*; D014158:Transcription, Genetic
D023081:CCAAT-Binding Factor; D004268:DNA-Binding Proteins; C497121:SP3 protein, human; D016329:Sp1 Transcription Factor; D014157:Transcription Factors; D051705:Sp3 Transcription Factor