Working on the Fly: New Research Reveals the Secrets of Sleep

Sleep is almost universal throughout the animal kingdom, and nature has developed many ways for different species to sleep.

Dolphins are able to put one hemisphere of their brains to sleep while the other hemisphere remains awake, allowing the dolphin to continue swimming and be aware of predators; migratory birds are able to enter into brief bouts of sleep—as quick as five to 10 seconds—midflight and can then continue flying for days; and though it may seem routine in comparison, humans also have very unique and complex sleep patterns.

Kyunghee Koh, PhD, associate professor in the Department of Neuroscience and principle investigator at Koh Laboratory, and her team are working tirelessly to understand the genetic and neural basis for sleep to help treat sleep disorders.

Although humans spend roughly a third of their lives asleep, there are still many questions surrounding why we do it. It is known that sleep is regulated by circadian rhythms and homeostatic processes and plays a part in memory consolidation, but the main functions of sleep remain largely unknown.

Koh and her team use Drosophila, the common fruit fly, as a model to study sleep because these flies share exceedingly similar sleep patterns with humans.

Koh’s team has discovered several novel circadian genes by conducting thousands of tests on fruit flies—a feat that would be impossible with mammalian subjects. Their most recent discovery, the gene taranis, is of particular interest because it also exists as a cell-cycle gene in humans and is now shown to play a part in brain function as well.    

Whether it’s working to meet an upcoming deadline, responding to a crying baby, or even just staying up late to watch a movie, humans are the only species that willingly delays sleep. Koh’s team has observed motivational drives in flies overpower sleep drives in similar ways; a prime example is that male flies will forego sleep to engage in mating activities. By isolating the brain regions that are active during these periods, and stimulating and suppressing these neural centers, Koh is able to observe how sleep is affected.

More than 50 million adults in the United States have trouble sleeping and, like a fingerprint, sleeplessness varies from person to person.

Through their research, Koh and her team hope to use what they’ve learned about fly sleep to lead the charge for new drug discovery and help people around the world rest easy again.

“We want to have personalized medicine,” Koh says, “and for that we really need to understand the basic science of how sleep is regulated.”