Figure 2.

IGF2‐DMR0 enhances the P0 promoter activity of IGF2 in TCL‐1 cells. A, Schematic illustration of IGF2 promoters. The broken arrows indicate the transcription start sites (TSSs) of each transcript from the P1, P0, P2, P3, and P4 promoters. The TSSs from P0, P3, and P4 were assigned based on GenBank accession numbers DQ104203.1, NM_000612.6, NM_001291861.2, respectively. IGF2‐DMR0 is paternally methylated. Boxes indicate exons. Blue boxes indicate coding regions. The up‐arrow shows the putative TATA box. The DNA fragments used in the luciferase assay are shown by thick horizontal lines. B, Structures of the constructs used in the luciferase assay. Luc: firefly luciferase gene. These constructs were transfected into TCL‐1 cells along with a Renilla luciferase (pRL‐TK) as an internal control. C, P0b activity was enhanced by IGF2‐DMR0. The activity of PGV‐B P0b was set to 1. D, P3 activity was unaffected by IGF2‐DMR0. The activity of PGV‐B P3 was set to 1. E, P4 activity was unaffected by IGF2‐DMR0. The activity of PGV‐B P4 was set to 1. Data represent mean values ± SD of three independent experiments. n.s.: not significant