PPARGC1A and obesity due to melanocortin 4 receptor deficiency: By using ChIP analysis, we further demonstratethat RAP1 binds to Pparα and Pgc1αloci in liver, and that can regulate transcription of Pparαand Pgc1α. In line with this,Rap1-deficient mice show decreased Pparαand Pgc1α expression and the subsequent deregulation ofsome of their target genes, leading to severe metabolic alterations that are inaccordance with the early onset of obesity found in these mice.