Molecular Switch Identified in Fat Burning Linked to Circadian Clock, Diet, and Temperature
Scientists at the University of Copenhagen and international collaborators have identified a molecular switch, a protein called SLC25A34, in the brown fat of mice that integrates three key metabolic controls: the body's 24-hour circadian clock, external temperature, and diet. This discovery, published in Science, helps explain how the body maintains a daily rhythm of energy metabolism while simultaneously adapting to immediate energy demands. Brown fat, a unique tissue that burns fuel to generate heat, typically has its lowest activity during sleep and increases before waking. The protein SLC25A34 acts as a switch, influenced by a clock protein (REV-ERBα) during sleep, cold temperatures which override the clock, and dietary fat or fasting. When SLC25A34 levels were lowered in brown fat cells, the fat-burning response was significantly weaker, indicating its crucial role in the cycle of building and burning fat to generate heat and clear blood lipids.
