Figure 6
dFOXO regulates transcription of the d4E-BP gene. (a) A selection of microarray-identified genes that are transcriptionally downregulated after 2 h of insulin stimulation in Kc167 cells and contain forkhead response elements (FHREs) in their genomic upstream or intronic sequences. (b) FHREs (red) at the d4E-BP locus; black boxes are exons. (c,d) Overexpression of Dp110DN alone does not induce transcription of d4E-BP in imaginal discs, but (e) coexpression of dFOXO strongly upregulates the gene. (f-h) Expression of human FOXO3a-TM induces expression of the d4E-BP enhancer trap line Thor1. (i) d4E-BP and dPKB interact genetically. The Thor1 mutation increases the ommatidial number in dPKB-mutants by 9% without affecting cell size. Values are shown ± SD. Genotypes are: (c) y w; GMR-Gal4 UAS-Dp110DN/+; (d) y w; GMR-Gal4 UAS-Dp110DN/+; (e) y w; GMR-Gal4 UAS-Dp110DN/+; EP-dFOXO/+; (f) y w; (g) y w; Thor1/+; (h) y w; Thor1/GMR-Gal4; UAS-hFOXO3a-TM/+; (i) from right to left: y w;; dPKB3/dPKB1, y w; Thor1/+; dPKB3/dPKB1, y w; Thor1/Thor1; dPKB3/dPKB1.