Body clock 'control switch' found
Researchers say they have identified the chemical switch that controls the genetic mechanism regulating people's internal body clocks.
Although the process involves complex genes, the whole mechanism is controlled by a single amino acid - a building block of protein - they say.
It is hoped the discovery may lead to more effective drugs to treat sleep disorders and related ailments.
The University of California study appears in the journal Nature.
Lead researcher Professor Paolo Sassone-Corsi said: "Because the triggering action is so specific, it appears to be a perfect target for compounds that could regulate this activity.
"It is always amazing to see how molecular control is so precise in biology."