Figure 3

Identification of the Dlk2 core promoter. A) Core promoter elements in the Dlk2 promoter sequence: Initiator element (Inr), Downstream Core Promoter Element (DPE), and six GC-boxes, putative binding sites for Sp1 transcription factor. B) Schematic representation of the CpG island present in the Dlk2 promoter, between positions -481 and +440. The grey square represents the localization of the CpG island; black lines represent GC dinucleotides, and dark squares represent Dlk2 exons. C) NIH3T3 cells were transiently transfected with pGL3Basic(-212/+1), pGL3Basic(-212/+177), pGL3Basic(-212/+421), or pGL3Basic(+1/+177), along with pRL-TK. Luciferase activity was measured 24 hours after transfection, and each luciferase value (Relative Light Units) was normalized to its corresponding value of Renilla activity. The average values of at least three independent experiments are shown. (*, ** and ***, significant versus control in Student's t-test with p-values < 0.05, < 0.01 and < 0.001, respectively).