CLOCK and obesity due to melanocortin 4 receptor deficiency: Tissue-intrinsic clock circuits confer temporal control to metabolic pathways to orchestrate metabolic homeostasis (Panda et al., 2002), and their dysregulation predispose to the development of obesity and insulin resistance (Turek et al., 2005; Scheer et al., 2009; Xiong et al., 2021).