Transcriptional promoter activity associated with exons 1A, 1B, and 1C.

Shown is firefly luciferase activity assayed 48 hours after transfection of HEK293T cells, relative to the activity of cells transfected in parallel with the promoterless pGL2 basic control vector. Assays were performed in triplicate and transfection efficiency was normalized with respect to cotransfected Renilla luciferase activity in the same cultures. As a positive control, luciferase activity expressed from a standard SV40 promoter is shown.