As its role in metabolism is unknown, we first monitored PTPR-γ expression in metabolically relevant tissues of mice either fed on a high-caloric-diet (HCD; an established model of obesity/T2DM)19, 20 or treated with lipopolysaccharides (LPS; an established model of inflammation/insulin resistance)21. Here, PTPRG is linked to obesity due to melanocortin 4 receptor deficiency.