Figure 2

E-box (-340) is essential for transcriptional activity of P1.1 in primary bovine trophoblast cells. Cells were transiently transfected with a promoterless luciferase reporter gene plasmid (pGL3), which served as a control, or with luciferase reporter gene plasmids containing the proximal sequence of P1.1 and part of the untranslated exon 1 (base pairs -404 to +113) with either a wild type (P1.1wt) or a mutated E-box (-340) motif (Emut), along with plasmid CMV-lacZ. Activities of the luciferase and lacZ reporter genes were measured 24 h after transfection. The quotient of the luciferase and β-galactosidase activities was calculated to normalise for transfection efficiency. Results are expressed as the mean ± S.E.M of n = 3 experiments. Different letters above the columns indicate significant differences (p < 0.05).