PFKM and obesity due to melanocortin 4 receptor deficiency: Although the present study did not directly address the effects of WSD and CR on fiber composition and metabolic properties of SM, the RNAseq analysis suggests that WSD induced the sustained downregulation of insulin signaling (IRS1), glycolytic (PFKM, PFKFB1), and mitochondrial (UCP3) genes and that this effect persisted after obesity was reversed with CR (Fig. 5).