PPARG and obesity due to melanocortin 4 receptor deficiency: Phosphorylation of PPARγ at Ser273 by cyclin-dependent kinase 5 (Cdk5) was recently linked to obesity, and anti-diabetic PPARγ ligands (e.g. the thiazolidinedione rosiglitazone) were shown to inhibit the Cdk5-mediated phosphorylation of PPARγ in adipose tissue [62].