Featured Research

from universities, journals, and other organizations

Researchers Show Mechanism And Similarities Of Biological Clocks

Date:
June 9, 1998
Source:
Northwestern University
Summary:
Scientists picking apart the inner workings of the biological clocks that govern the daily cycles of life have now identified several key cogs of the machinery and have shown that these main parts are remarkably similar between invertebrates and mammals.

Scientists picking apart the inner workings of the biological clocks that govern the daily cycles of life have now identified several key cogs of the machinery and have shown that these main parts are remarkably similar between invertebrates and mammals.

Related Articles


In the June 5 issue of Science, one team describes the working parts that drive the clock in mice forward like a watch spring, and in another paper another team for the first time identifies the gene in fruit flies that corresponds to the mammalian Clock gene and shows how it can turn itself off again, enabling it to oscillate like a pendulum.

"We always thought that circadian clocks might work the same way in different organisms, but this is really the first evidence -- with the same genes playing the same role in flies and mice," says Joseph S. Takahashi, professor of neurobiology and physiology at Northwestern University, who is an author on both papers and last year was the first to clone the mammalian clock gene.

"We now have three different circadian clock genes that are conserved between insects and mammals," Takahashi said. "These genes define a surprisingly simple and elegant feedback loop of gene activation and inhibition that composes the core mechanism of the clock in animals."

In the first paper, Charles Weitz and coworkers at Harvard Medical School, with Takahashi's group at Northwestern, searched for and identified a protein molecule that can bind to the protein, CLOCK, produced by the mouse Clock gene. This protein molecule, called BMAL1, is produced at the same time and in the same regions of the brain as the CLOCK protein.

The CLOCK-BMAL1 pair, they showed, is capable of binding to and turning on a genetic switch that regulates another gene, which is called mper-1 because it is the mammalian version of the period gene, which is required for circadian rhythm in flies.

"We think this 'on' mechanism accounts for the positive component of the oscillation that drives the circadian rhythm," Takahashi said.

The backward swing of the pendulum -- an "off" genetic switch -- was found by a group tinkering with the clockwork in fruit flies. That team, headed by Steve A. Kay at Scripps Research Institute, in collaboration with Takahashi's and Weitz's laboratories, showed that the fly's CLOCK protein teams up with a fly version of BMAL to bind to the genetic switch and turn on production of the proteins PERIOD and TIMELESS. These latter two proteins, they showed, were an "off" switch that blocked the ability of the CLOCK-BMAL pair to activate the genes for PERIOD and TIMELESS production -- a finding that "closed the circadian loop," according to the authors, and accounted for the on-again/off-again genetic oscillation.

Circadian (Latin for "around the day") clocks regulate daily activities such as sleep and wakefulness. Difficulty in readjusting our clocks causes jet lag and shift work problems, as well as some types of sleep disorders. The clock may also explain why heart attacks occur more often in the morning and asthma flare-ups more often at night.

Some neurobiologists believe that higher species evolved more specialized mechanisms built around the ancient "core oscillator." These accessories would allow an organism to harness the clock to suit to its own needs and changing conditions of light or temperature.

Other authors on the two Science papers are Thomas K. Darlington, Karen Wager-Smith and M. Fernanda Geriani from Scripps; Nicholas Gekakis, David Staknis and Hubert B. Nguyen from Harvard; Fred C. Davis from Northeastern University; and Thomas D.L. Steeves, Lisa D. Wilsbacher and David P. King from Northwestern.

The research at Northwestern was funded by the NSF Center for Biological Timing and the National Institutes of Health. Takahashi is a researcher in the Howard Hughes Medical Institute.


Story Source:

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


Cite This Page:

Northwestern University. "Researchers Show Mechanism And Similarities Of Biological Clocks." ScienceDaily. ScienceDaily, 9 June 1998. <www.sciencedaily.com/releases/1998/06/980609081138.htm>.
Northwestern University. (1998, June 9). Researchers Show Mechanism And Similarities Of Biological Clocks. ScienceDaily. Retrieved October 31, 2014 from www.sciencedaily.com/releases/1998/06/980609081138.htm
Northwestern University. "Researchers Show Mechanism And Similarities Of Biological Clocks." ScienceDaily. www.sciencedaily.com/releases/1998/06/980609081138.htm (accessed October 31, 2014).

Share This



More Plants & Animals News

Friday, October 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Watch Baby Goose Survive A 400-Foot Cliff Dive

Watch Baby Goose Survive A 400-Foot Cliff Dive

Buzz60 (Oct. 31, 2014) For its nature series Life Story, the BBC profiled the barnacle goose, whose chicks must make a daredevil 400-foot cliff dive from their nests to find food. Jen Markham has the astonishing video. Video provided by Buzz60
Powered by NewsLook.com
World's Salamanders At Risk From Flesh-Eating Fungus

World's Salamanders At Risk From Flesh-Eating Fungus

Newsy (Oct. 31, 2014) The import of salamanders around the globe is thought to be contributing to the spread of a deadly fungus. Video provided by Newsy
Powered by NewsLook.com
Alcoholic Drinks In The E.U. Could Get Calorie Labels

Alcoholic Drinks In The E.U. Could Get Calorie Labels

Newsy (Oct. 31, 2014) A health group in the United Kingdom has called for mandatory calorie labels on alcoholic beverages in the European Union. Video provided by Newsy
Powered by NewsLook.com
Malaria Threat in Liberia as Fight Against Ebola Rages

Malaria Threat in Liberia as Fight Against Ebola Rages

AFP (Oct. 31, 2014) Focus on treating the Ebola epidemic in Liberia means that treatment for malaria, itself a killer, is hard to come by. MSF are now undertaking the mass distribution of antimalarials in Monrovia. Duration: 00:38 Video provided by AFP
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:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

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