Sp1 increased basal promoter activity could be abrogated by the GC boxes mutation. A, Sp1 enhances the core promoter activity of Zbtb7Agene. HepG-2 and 293 T cells were transient co-tranfected with either pLuc-1000 and pCDNA3.1, or Sp1 and pLuc-10000 or SpAm or SpBm. pGl4.10 was control B, RT-PCR analysis of Zbtb7AmRNA using the total RNA was isolated from 293 T cells tranfected Sp1.GAPDH was control. Data for A means for ± SD from three independent experiments, with each experiment carried out in triplicate.