May 6, 2011
Sleep Pathway Discovered
(Ivanhoe Newswire) -- Worms may help researchers understand more about sleep. A team of neurobiologists at Brown University and elsewhere discovered that "Notch," a signaling pathway found in all animals, is directly involved in sleep in the nematode C. elegans.
"We understand sleep as little as we understand consciousness," Anne Hart, associate professor of neuroscience at Brown and the paper's senior author, was quoted as saying. "We're not clear why sleep is required, how animals enter into a sleep state, how sleep is maintained, or how animals wake up. We're still trying to figure out what is critical at the cellular level and the molecular level."
Other experiments showed that the worms lacking osm-11 and the related osm-7 genes were hyperactive and exhibited twice as many body bends each minute compared to normal nematodes. The more Notch signaling was turned on, the sleepier the worms became. When it was suppressed, the worms would go into overdrive and become too active.
In humans, the gene called Deltalike1 is most similar to osm-11. It is expressed in regions of the brain associated with the sleep-wake cycle.
Researchers say manipulating Notch signaling is tricky because it is implicated in a lot of different activities in the body. "Too much Notch signaling can cause cancer, so we would have to be very targeted in how we manipulate it," Hart said. "One of the next steps we're going to take is to look at the specific steps in Notch signaling that are pertinent to arousal and quiescence."
SOURCE: Current Biology, May, 2011