Nicolás M, Noé V, Jensen K B, Ciudad C J
Department of Biochemistry and Molecular Biology, School of Pharmacy, University of Barcelona, 08028 Barcelona, Spain.
J Biol Chem. 2001 Jun 22;276(25):22126-32. doi: 10.1074/jbc.M010740200. Epub 2001 Apr 9.
The 5'-flanking region of the human Sp1 gene was cloned and characterized. Sequence analysis of this region showed the absence of both CAAT and TATA boxes and an initiator element. The proximal promoter of the Sp1 gene is a GC-rich region that contains multiple GC boxes and Ap2 binding sites. The major transcription start site is located 63 base pairs upstream of the translation start site. Transfection experiments demonstrate that all the elements necessary to achieve significant basal transcription activity are located between positions -443 and -20 relative to the translational start. Sp1 and Sp3 proteins bind to the downstream GC box located in the proximal promoter of Sp1. Furthermore, we demonstrate that the Sp1 protein activates Sp1 transcription activity; thus the Sp1 gene is autoregulated.
克隆并鉴定了人类Sp1基因的5'侧翼区域。对该区域的序列分析表明，既没有CAAT盒也没有TATA盒，并且存在一个起始子元件。Sp1基因的近端启动子是一个富含GC的区域，包含多个GC盒和Ap2结合位点。主要转录起始位点位于翻译起始位点上游63个碱基对处。转染实验表明，实现显著基础转录活性所需的所有元件都位于相对于翻译起始的-443至-20位之间。Sp1和Sp3蛋白与位于Sp1近端启动子中的下游GC盒结合。此外，我们证明Sp1蛋白激活Sp1转录活性；因此，Sp1基因是自我调节的。
