CLOCK and Obesity: 2006), such as thermogenic gene programming in BAT. Ucp1 expression exhibits a strong circadian rhythmicity, being (among others) controlled by Rev‐erbα, a powerfull circadian transcriptional repressor (Gerhart‐Hines et al. 2013). In this context, and because RORα is also a partner of the clock machinery, we investigated the possibility of a circadian control of thermogenic genes in WAT, which we then compared to the pattern in BAT, in view of offering an explanation for how RORα‐deficient mice could be resistant to obesity.