Indian-origin scientist's find on worms demystifies neurobiology of sleep

A new worm research, led by an Indian-origin scientist, may help explain the neurobiology of sleep in a wide variety of creatures, including humans.

Komudi Singh, a postdoctoral fellow in the Department of Neuroscience at Brown University and colleagues from several other institutions have found that 'Notch', a fundamental signaling pathway found in all animals, is directly involved in sleep in the nematode C. elegans.

"This pathway is a major player in development across all animal species," said Anne Hart, associate professor of neuroscience at Brown.

"The fact that this highly conserved pathway regulates how much these little animals sleep strongly suggests that it's going to play a critical role in other animals, including humans. The genes in this pathway are expressed in the human brain," she said.

The findings, Hart added, could help to develop more precise and safer sleep aids.

Hart found that adult nematodes in which Notch pathway genes (like osm-11) were overexpressed were doing something quite bizarre.

"Normally, adult nematodes spend all of their time moving. But, these animals suddenly start taking spontaneous 'naps.' It was the oddest thing I'd seen in my career," she said.

Other experiments showed that worms lacking osm-11 and the related osm-7 genes were hyperactive, exhibiting twice as many body bends each minute as normal nematodes.

In humans, the gene that is most similar to osm-11 is called Deltalike1 (abbreviated DLK1). It is expressed in regions of the brain associated with the sleep-wake cycle.

The study is detailed in the May 24 issue of the journal Current Biology.