Waking up to sleep secrets

The biochemistry behind sleepiness has been found in somnolent rodents.

A good night’s sleep after a long day can feel like hitting the refresh button, but how the brain monitors the need for a nap is not well understood. A team led by University of Tsukuba researchers compared the chemical activity in the brains of well-rested mice, sleep-deprived mice and mice with a genetic mutation — aptly named Sleepy — that causes them to always seek extra sleep. The team identified 80 proteins that accumulated more phosphates by a process called phosphorylation, which can alter protein function, in than in the well-rested mice. The process was reversed after the tired rodents had slept, and could explain how the brain tracks how long it has been awake or asleep.

Understanding the sleep−wake cycle could help researchers find the best sleeping pattern for improving brain function.