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 September 2, 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 September 2, 2014).

Share This




More Health & Medicine News

Tuesday, September 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

U.N. Says Ebola Travel Restrictions Will Cause Food Shortage

U.N. Says Ebola Travel Restrictions Will Cause Food Shortage

Newsy (Sep. 2, 2014) — The U.N. says the problem is two-fold — quarantine zones and travel restrictions are limiting the movement of both people and food. Video provided by Newsy
Powered by NewsLook.com
Get on Your Bike! London Cycling Popularity Soars Despite Danger

Get on Your Bike! London Cycling Popularity Soars Despite Danger

AFP (Sep. 1, 2014) — Wedged between buses, lorries and cars, cycling in London isn't for the faint hearted. Nevertheless the number of people choosing to bike in the British capital has doubled over the past 15 years. Duration: 02:27 Video provided by AFP
Powered by NewsLook.com
Can You Train Your Brain To Eat Healthy?

Can You Train Your Brain To Eat Healthy?

Newsy (Sep. 1, 2014) — New research says if you condition yourself to eat healthy foods, eventually you'll crave them instead of junk food. Video provided by Newsy
Powered by NewsLook.com
We've Got Mites Living In Our Faces And So Do You

We've Got Mites Living In Our Faces And So Do You

Newsy (Aug. 30, 2014) — A new study suggests 100 percent of adult humans (those over 18 years of age) have Demodex mites living in their faces. 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