Figure 6. Transcriptional regulation of FOXO1 in the VMH.

(A) Heat map demonstrating gene expression profiling in the VMH of WT and Foxo1 KO^Sf1 mice. Relative fold changes of genes involved in indicated signaling pathways are shown (WT value = 1). (B) Sf1 mRNA levels in the VMH of 24-hour–fasted WT and Foxo1 KO^Sf1 mice (*P < 0.05, t test). (C) Schematic diagram of the 5′-flanking region of the mouse Sf1 gene, including the location of potential FOXO1 binding sites (white boxes). Shown below are the 5′-deletion constructs. Genomic alignments of SF-1 5′-flanking region of mammals (around FOXO1 putative binding sites). Red indicates the putative FOXO1 binding sites. (D) ChIP analysis showing direct binding of FOXO1 on the SF-1 promoter region in the VMH. (E) SF-1 promoter activity is significantly repressed by FOXO1 in Neuro2A cells in a dose-dependent manner (**P < 0.0001, only for –240 mSF-1, 1-way ANOVA). (F) SF-1 promoter activity is significantly repressed by a constitutive nuclear active form of FOXO1 (FOXO1-CN) in a dose-dependent manner but not by a DNA-binding deletion mutant of FOXO1 (CN-DBD) in Neuro2A cells (**P < 0.0001, only for –240 mSF-1, 1-way ANOVA). (G and H) SF-1 protein levels in 24-hour–fasted WT and Foxo1 KO^Sf1 animals (*P < 0.05, t test). The data are expressed as mean ± SEM (B, E, F, and H).