Featured Research

from universities, journals, and other organizations

New fruitfly sleep gene promotes the need to sleep

Date:
February 4, 2014
Source:
University of Pennsylvania School of Medicine
Summary:
All creatures great and small, including fruitflies, need sleep. The timing of when we sleep versus are awake is controlled by cells in tune with circadian rhythms of light and dark. Most of the molecular components of that internal clock have been worked out. On the other hand, what drives how much we sleep is less well understood. Researchers report a new protein involved in the homeostatic regulation of sleep in the fruitfly.

This is an alpha subunit of the nicotinic acetylcholine receptor accounts for the rye mutant phenotype. Expression pattern of redeye (green).
Credit: Amita Sehgal and Mi Shi, PhD, Perelman School of Medicine, University of Pennsylvania; eLife

All creatures great and small, including fruitflies, need sleep. Researchers have surmised that sleep -- in any species -- is necessary for repairing proteins, consolidating memories, and removing wastes from cells. But, really, sleep is still a great mystery.

The timing of when we sleep versus are awake is controlled by cells in tune with circadian rhythms of light and dark. Most of the molecular components of that internal clock have been worked out. On the other hand, how much we sleep is regulated by another process called sleep homeostasis, however little is known about its molecular basis.

In a study published in eLIFE, Amita Sehgal, PhD, professor of Neuroscience at the Perelman School of Medicine, University of Pennsylvania, and colleagues, report a new protein involved in the homeostatic regulation of sleep in the fruitfly, Drosophila. Sehgal is also an investigator with the Howard Hughes Medical Institute (HHMI).

The researchers conducted a screen of mutant flies to identify short-sleeping individuals and found one, which they dubbed redeye. These mutants show a severe reduction in the amount of time they slumber, sleeping only half as long as normal flies. While the redeye mutants were able to fall asleep, they would wake again in only a few minutes.

The team found that the redeye gene encodes a subunit of the nicotinic acetylcholine receptor. This type of acetylcholine receptor consists of multiple protein subunits, which form an ion channel in the cell membrane, and, as the name implies, also binds to nicotine. Although acetylcholine signaling -- and cigarette smoking -- typically promote wakefulness, the particular subunit studied in the eLIFE paper is required for sleep in Drosophila.

Levels of the redeye protein in the fly oscillate with the cycles of light and dark and peak at times of daily sleep. Normally, the redeye protein is expressed at times of increasing sleep need in the fly, right around the afternoon siesta and at the time of night-time sleep. From this, the team concluded that the redeye protein promotes sleep and is a marker for sleepiness -- suggesting that redeye signals an acute need for sleep, and then helps to maintain sleep once it is underway.

In addition, cycling of the redeye protein is independent of the circadian clock in normal day:night cycles, but depends on the sleep homeostat. The team concluded this because redeye protein levels are upregulated in short-sleeping mutants as well as in wild-type animals following sleep deprivation. And, mutant flies had normal circadian rhythms, suggesting that their sleep problems were the result of disrupted sleep/wake homeostasis.

Ultimately the team wants to use the redeye gene to locate sleep homeostat neurons in the brain. "We propose that the homeostatic drive to sleep increases levels of the redeye protein, which responds to this drive by promoting sleep," says Sehgal. Identification of molecules that reflect sleep drive could lead to the development of biomarkers for sleep, and may get us closer to revealing the mystery of the sleep homeostat.


Story Source:

The above story is based on materials provided by University of Pennsylvania School of Medicine. Note: Materials may be edited for content and length.


Journal Reference:

  1. M. Shi, Z. Yue, A. Kuryatov, J. M. Lindstrom, A. Sehgal. Identification of Redeye, a new sleep-regulating protein whose expression is modulated by sleep amount. eLife, 2014; 3 (0): e01473 DOI: 10.7554/eLife.01473

Cite This Page:

University of Pennsylvania School of Medicine. "New fruitfly sleep gene promotes the need to sleep." ScienceDaily. ScienceDaily, 4 February 2014. <www.sciencedaily.com/releases/2014/02/140204131700.htm>.
University of Pennsylvania School of Medicine. (2014, February 4). New fruitfly sleep gene promotes the need to sleep. ScienceDaily. Retrieved April 21, 2014 from www.sciencedaily.com/releases/2014/02/140204131700.htm
University of Pennsylvania School of Medicine. "New fruitfly sleep gene promotes the need to sleep." ScienceDaily. www.sciencedaily.com/releases/2014/02/140204131700.htm (accessed April 21, 2014).

Share This



More Health & Medicine News

Monday, April 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Nine-Month-Old Baby Can't Open His Mouth

Nine-Month-Old Baby Can't Open His Mouth

Newsy (Apr. 19, 2014) — Nine-month-old Wyatt Scott was born with a rare disorder called congenital trismus, which prevents him from opening his mouth. Video provided by Newsy
Powered by NewsLook.com
'Holy Grail' Of Weight Loss? New Find Could Be It

'Holy Grail' Of Weight Loss? New Find Could Be It

Newsy (Apr. 18, 2014) — In a potential breakthrough for future obesity treatments, scientists have used MRI scans to pinpoint brown fat in a living adult for the first time. Video provided by Newsy
Powered by NewsLook.com
Little Progress Made In Fighting Food Poisoning, CDC Says

Little Progress Made In Fighting Food Poisoning, CDC Says

Newsy (Apr. 18, 2014) — A new report shows rates of two foodborne infections increased in the U.S. in recent years, while salmonella actually dropped 9 percent. Video provided by Newsy
Powered by NewsLook.com
Scientists Create Stem Cells From Adult Skin Cells

Scientists Create Stem Cells From Adult Skin Cells

Newsy (Apr. 17, 2014) — The breakthrough could mean a cure for some serious diseases and even the possibility of human cloning, but it's all still a way off. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins