MAP3K5 and obesity due to melanocortin 4 receptor deficiency: Because of the reduction in the activation of redox-dependent ASK1/TGF-β signaling and ZPR9 expression in both genetic and diet-induced obese mice compared to control wild-type and chow mice1, we next assessed whether ZPR9 can improve obesity-associated metabolic disturbances in diet-induced obese mice by stimulating MPK38 activity (Fig. 10).