TABLE 1.

Promoter usage in the model cell lines^a

Cell line	Reporter activity
	P4 Luc/P1 Luc	Full promoter ΔP4 Luc/ full promoter Luc	P4 Luc/RSV Luc
HeLa	24.80 ± 2.32	0.063 ± 0.003	0.080 ± 0.032
Caki1	65.24 ± 5.21	0.113 ± 0.021	0.072 ± 0.025
HT3	81.46 ± 7.36	0.002 ± 0.001	0.021 ± 0.001
JAR	30.16 ± 4.55	0.074 ± 0.022	0.042 ± 0.003
MG3	53.9 ± 3.12	0.001 ± 0.0005	0.072 ± 0.002

^aP4 Luc, FR-α P4 promoter fragment (nt −271 to +33) plus luciferase; P1 Luc, FR-α P1 promoter fragment (nt −3394 to −2468) plus luciferase; full promoter Luc, FR-α gene fragment spanning both P1 and P4 (nt −3394 to +33) plus luciferase; full promoter ΔP4 Luc, full promoter Luc containing a deletion of Sp1 sites in P4 (nt −140 to −30); RSV Luc, RSV promoter plus luciferase. The transcription start site in the P4 promoter is considered to be nt +1. The constructs were inserted in the PGL3 basic plasmid. Transfection efficiencies were normalized to that of a cotransfected β-galactosidase control.