Transcriptional activity of rat vitamin K–dependent carboxylase mutant reporter plasmids in H4IIEC3 cells. The extent of the 5′-flanking sequence contained in each reporter plasmid is indicated below the figure. (A) Reporter plasmids RCBX2634 through RCBX210. The average normalized luciferase activity relative to RCBX2634 is shown, n = 5. Error bars = SD. (B) Reporter plasmids RCBX210 through RCBX18. The average activity relative to RCBX210 is shown, n = 5. pGL3 = pGL3-Basic without insert. (C) Deletion of the 12-bp sequence (–76 to –65) from the 2634 bp 5′-flanking region (D12) abolishes transcriptional activity of RCBX2634. D12 = RCBX2634D12, n = 3.