Institute for Diabetes, Obesity and Metabolism, Department of Genetics, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA. kaestner@mail.med.upenn.edu
All vertebrate animals have developed a sophisticated regulatory system to cope with frequent and unpredictable episodes of fasting. A recent letter to Nature suggests that a switch from early gluconeogenic gene activation via CRTC2 (also known as TORC2) to late action of FOXO1 is critical to this process.