Fig. 1

Domain architecture and sequence alignment of FOXO proteins. A Schematic domain structure of FOXO proteins. The Forkhead DNA-binding domain (DBD), nuclear localization signal (NLS), nuclear export signal (NES), and transcriptional activation domain (TAD) are colored green, orange, red, and blue, respectively. Conserved AKT phosphorylation sites in mammalian and C. elegans FOXO proteins are indicated with corresponding amino acid positions (S for serine, T for threonine). The hydrophobic residues of the “ΦxxΦΦ” motif are shaded in yellow. B The sequence alignment of the Forkhead DBDs from FOXO proteins is presented with reference to the secondary structural elements (H for α-helix, S for β-strand, W for wing). Identical and highly conserved amino acids are shaded in blue and yellow, respectively. C A three-dimensional structure of the Forkhead DBD is depicted