Fig. 2.

Schematic representation of transcriptional control of pyruvate dehydrogenase kinase 4 (PDK4) expression. Activation of Akt/PKB signaling by insulin phosphorylates forkhead box protein O (FOXO) and suppresses PDK4 expression. Several nuclear receptors, including estrogen-related receptor (ERR), peroxisome proliferator-activated receptor (PPAR), glucocorticoid receptor (GR), and thyroid hormone receptor (TR), participate in the transcriptional regulation of PDK4 and coordinate with coactivators, including peroxisome proliferator-activated receptor gamma coactivator 1-α (PCG-1α) and CCAAT/enhancer binding protein β (C/EBPβ).