In its normal state, the Drosophila (fruit fly) gene, called Shaker, produces an ion channel that controls the flow of potassium into cells, a process that critically affects, among other things, electrical activity in neurons. A handful of recent studies suggest that potassium channels are also involved in the generation of sleep in humans.
Reported in the April 28 issue of Nature, the finding points to novel approaches to treating sleep irregularities in humans-from promoting restorative sleep to prolonging wakefulness.
"This research offers the possibility of developing a new class of compounds that could affect potassium channels in the brain rather than other brain chemical systems targeted currently," says lead author Dr. Chiara Cirelli, assistant professor of psychiatry at UW Medical School.
UW-Madison genetics professor Barry Ganetsky, likely the world expert on the Shaker gene, was a collaborator on the study. Dr. Giulio Tononi, UW Medical School professor of psychiatry, was the senior author on the paper.
Most people sleep seven to eight hours a night, and if they are deprived of sleep, their cognitive performance suffers greatly. However, a few people do well with just three or four hours of sleep-a trait that seems to run in families.
"We wanted to determine which genes underlie this phenomenon in order to shed light on the mechanisms and functions of sleep," Tononi says.
The Wisconsin study focuses on factors that control sleep duration as opposed to the timing of when sleep occurs, which is regulated by the circadian system, Tononi notes. "The key molecular mechanisms controlling the circadian timing of sleep are well understood, but details about the homeostatic mechan