Neurodegenerative disease gene can boost sleep

A gene involved in neurodegenerative disease can play a crucial role in the proper function of the circadian clock, a new study has found.

Northwestern University scientists carried out research into the common fruit fly and found the Ataxin-2 gene, which keeps the circadian clock responsible for sleeping and waking on a 24 hour rhythm.

If the gene is not used, the rhythm of the fruit fly’s sleep wake cycle is disturbing, leading to difficulties when it comes to waking up on a regular schedule.

Mutations in the human Ataxin-2 gene are also known to cause a rare disorder entitled spinocerbellar ataxia, while contributing to amyotrophic lateral sclerosis (ALS), with sufferers of this disease being affected by sleep abnormalities before other symptoms.

Studies also found that Ataxin-2 helps activate translation of PER RNA into PER protein, which represents a key step in making the circadian clock run properly.

Ravi Allada, professor of neurobiology in the Weinberg College of Arts and Sciences, said: “It's possible that Ataxin-2's function as an activator of protein translation may be central to understanding how, when you mutate the gene and disrupt its function, it may be causing or contributing to diseases such as ALS or spinocerebellar ataxia.”

Mr Allada noted flies sleep similarly to humans and added that Ataxin-2 is the second gene in a little over two years that Northwestern researchers have specified as a core gear of the circadian clock.

“We've really started to define a pathway that regulates the circadian clock and seems to be especially important in a specific group of neurons that governs the fly's morning wake-up.

“We saw that the molecular and behavioral consequences of losing Ataxin-2 are nearly the same as losing twenty-four,” he continued.

It was found that, when the Ataxin-2 gene is not present, minimal PER protein is located in the circadian pacemaker neurons of the brain, leading to interruptions in the fly’s sleep-wake rhythm.

Posted by Fiona Griffiths