Figure 1.

Schematic representation of the main findings from the dual publication (Koronowski et al., 2019; Welz et al., 2019) commented. The mouse model reconstituting Bmal1 expression exclusively in the epidermis (Bmal1-RE mouse) or the liver (Liver-RE mouse) was generated from a conventional full-body Bmal1 knockout mouse (Bmal1-KO). In mammals, the brain central clock works as a master circadian coordinator of the rest of circadian clocks in the body. The autonomous responses in Bmal1 reconstituted organs (epidermis or liver) ensured basic homeostasis of the organs (e.g., epidermal turnover, glycogen metabolism) and were only dependent on inputs of light and darkness. WT, wild type.