In my last two blog posts, I explored recent “cross-translational research” that looked at similarities between human and fruit fly genes and came up with a previously unrecognized genetic indicator of sleep deprivation. The things we never thought fruit flies could do…
In exploring that research, I stumbled across another sleep study using fruit flies to draw links with human genetics. The Ataxin-2 gene, previously known to be involved with instances of neurodegenerative disease, also affects human circadian rhythm.
Ataxin-2 and Circadian Rhythm
In a controlled study of fruit fly genetics, researchers from Northwestern University found Ataxin-2 to be responsible for maintaining a 24-hour sleep-wake cycle. When the gene isn’t active, the 24-hour Circadian rhythm is disturbed, making it hard to wake up on a regular schedule.
In humans, mutations in the same gene is implicated in rare neurological diseases including spinocerebellar ataxia and amyotrophic lateral sclerosis (or Lou Gehrig’s Disease). People with spinocerebellar ataxia, in particular, have been known to suffer from sleep disorders as an early symptom that presents before other disease indicators.
The study, undertaken by Dr. Ravi Allada at the Weinberg College of Arts and Sciences and post-doctoral fellow Chunghun Lim, was published in the May issue of the journal Science and reported in Science Daily.
Sleep Research and the Humble Fruit Fly
Since classic fruit flies (Drosophila melanogaster) share a high rate of similarity with human genes, especially those that help regulate sleep, these fruit flies are particularly suited to help sleep researchers identify human genetic markers that impact sleep. Fruit flies are easy to breed and maintain in a laboratory setting. The 24-hour sleep-wake timing cycle is thought to stem from a biological timing cycle evolved from a common animal ancestor many millions of years ago.
Ataxin-2, along with another gene Allada’s team has dubbed “twenty-four” works as a protein translator for the protein PER, which acts as a “circadian pacemaker” for neurons in the brain. When PER is not activated at appropriate levels, the sleep-wake rhythm is disturbed. Fruit flies were key to helping researchers understand this complex chemical relationship, with implications for the future of both sleep research and neurological disease treatment.