The physiological function of endogenous D-serine remains a mystery. Here the authors show that endogenous D-serine plays an important role in regulating sleep and that, while the D-serine synthesizing enzyme serine racemase (SR) is expressed both in the nervous system and the intestines, the SR in the intestine is shown to be functionally sufficient for sleep regulation.
- Xihuimin Dai
- Enxing Zhou
- Yi Rao
