Researchers from the Perelman School of Medicine at the University of Pennsylvania have found a single gene, called nemuri, that increases the need for sleep.
The reserach team found a single gene in fruit flies that boosts sleep when insects are sick or exhausted, according to a paper published today in Science.
“While it’s a common notion that sleep and healing are tightly related, our study directly links sleep to the immune system and provides a potential explanation for how sleep increases during sickness,”
– Senior author Amita Sehgal, PhD, a professor of Neuroscience and director of Penn’s Chronobiology Program, in a release.
While previous tests identified genes that reduce sleep when they’re missing, this is the first fly study to identify a single gene that, when overactive, improves sleep. An abundance of nemuri also helped the flies fight infection, presenting a clear connection between this sleep gene and the immune system.
The newfound gene is named ‘nemuri’ which is a Japanese word for sleep. Its discovery has opened up new avenues to understanding how sleep works inside the brain, which may eventually help scientists answer the elusive question of why we sleep.
The researchers discovered that without the nemuri gene, flies were more easily aroused during daily sleep, and their acute need for an increase in sleep was reduced.
On the other hand, sleep deprivation, which increases the need for sleep, and to some extent infection, stimulated nemuri to be expressed in a small set of fly neurons. And overexpression of the nemuri gene instead increased sleep in bacteria-infected flies and led to their increased survival compared to non-infected control flies.
The team now want to find out if other species, including humans, have a nemuri gene or a gene like it.