For the majority of us, we need seven to eight hours of sleep to get what we call “a good night’s rest.” But why is that some people can function on a lot less? What about them allows for this perplexing phenomenon? Is it psychological or is it physiological?
Kyunghee Koh Ph.D., Assistant Professor of Neuroscience at Thomas Jefferson University, thinks she may have found a potential reason: taranis and Cyclin-dependent kinase (Cdk1). These two genes, previously recognized for their role in regulating cell division, are also essential for normal sleep in flies.
“There’s a lot we don’t understand about sleep, especially when it comes to the protein machinery that initiates the process on the cellular level,” says Dr. Koh. “Our research elucidates a new molecular pathway and a novel brain area that play a role in controlling how long we sleep.”
After examining the genetic makeup of thousands of flies, it became apparent that flies with the mutant gene taranis slept a lot less than normal flies. Using a series of genetic and biochemical experiments, the researchers tracked how taranis interacted with other proteins and saw that taranis bound to a known sleep regulator protein called Cyclin A. Their data suggest that taranis and Cyclin A create a molecular machine that inactivates Cdk1. This inactivation, in turn, suppresses sleep and promotes wakefulness. Therefore, taranis activity is directly related to the suppression of sleep.
Image Source: Morsa Images
Previous research has shown that Cyclin A is expressed in a small number of neurons, including a cluster of seven neurons on each side of the brain. Dr. Koh showed that these neurons are located in an area of the fly brain that corresponds with the human hypothalamus–one of the sleep centers of the human brain. They saw a reduction of overall sleep when taranis was knocked down (suppressed) only in these 14 neurons and when these same neurons are activated. “We think this may be an arousal center in the fly brain that taranis helps inhibit during sleep,” says Dr. Koh.
This research, although centered on flies, may have profound implications for humans as well; the taranis gene in flies has a human cousin called the Trip-Br family of transcriptional regulators. However, because it is uncertain whether a similar system exists for humans, Dr. Koh and her team plan to first examine the cues that turn taranis on and which proteins the Cdk1 kinase acts on to prevent sleep prior to advancing to human trials.
This study introduces a vast realm of possibilities. Dr. Koh concluded her study by stating that that if her hypothesis is true and we humans have a sleep mechanism similar to taranis, new drugs specifically targeting this molecular mechanism could be manufactured to help us sleep better.
Feature Image Source:Angel Sleeps by planetchopstick