FIGURE 6.

FOXO1 suppression maps to the proximal Lhb promoter. A, a schematic illustrates the location of binding elements for SP1, SF1, EGR1, and PTX1 transcription factors. B–D, the −1800, −500, −300, −150, and −87 Lhb-luc reporters were transiently transfected into LβT2 cells along with pcDNA3 empty vector (EV) or FOXO1 as indicated. After overnight starvation in serum-free media, cells were treated for 6 h with 0.1% BSA vehicle (Veh) or 10 nm GnRH. The results represent the mean ± S.E. of at least three experiments performed in triplicate and are presented as luc/β-gal (B), basal transcription relative to empty vector (C), or -fold GnRH induction relative to the vehicle control (D). * indicates that Lhb-luc transcription is significantly repressed by FOXO1 compared with EV using one-way ANOVA followed by Tukey's post-hoc test.