Navigation Links
A resetting signal keeps circadian rhythm on track in Drosophila fruit flies

A Brandeis University study published this week in Nature shows for the first time that a molecular signal maintains coherence among brain clock cells that regulate daily activity of Drosophila melanogaster (fruit flies). The two key groups of neurons control morning and evening activity and are maintained in synch even when the flies are plunged into darkness for extended periods of time.

This daily resetting signal flows from the morning to the evening cells and maintains a 12-hour difference between the timing of morning and evening activity, without the need for any environmental cues. The Brandeis researchers came to this conclusion by speeding up only the morning cell clock or only the evening cell clock. The results showed clearly that these two clocks always remained coupled in a network that was governed by the morning cell signal.

"We think it very likely that something similar is occurring in the brain of mammals, including humans, because their clock neurons also maintain remarkable coherence," said Professor Michael Rosbash, director of the National Center for Behavioral Genomics at Brandeis, and a Howard Hughes Medical Institute investigator. "However, circadian brain anatomy in mammals is much more complicated and the tools much too primitive to allow a similar network approach at this time. Flies are state-of-the art. Fortunately, their circadian clocks and even neural mechanisms are quite conserved with mammals."

"We were curious about how these brain cells stay synchronized, so we controlled the way time was ticking in individual clocks: we made the morning cells run faster and the evening cells relatively slower, and the other way around," explained researcher Dan Stoleru. "In this fashion, we introduced phase differences between them. It turned out that no matter the manipulation, the morning cells set the pace of the entire system, so that the rhythm always stayed on track."

The study showed that the mornin g clock resets the evening clock every day, without changing the intrinsic speed of the evening clock. Between daily resets, therefore, the evening cells time evening activity with their own clock, but they will always start counting time from the moment they were reset by the morning cells. In other words, the evening clock triggers the alarm at its own pace, but it is the morning clock which sets the alarm every day.

"So if you are looking over several days, only one period will be observed ?the one dictated by the morning clock," Stoleru said.

Research by the same Brandeis team, published last year in Nature, had shown that two distinct groups of clock neurons determine morning and evening activity. The present study greatly advanced the understanding of how temporal coherence between these two cell groups, and between their behavioral outputs, is achieved.


Source:Brandeis University

Related biology news :

1. Travelers can avoid jet lag by resetting their body clocks
2. Plants respond similarly to signals from friends, enemies
3. Bound for destruction: Ubiquitination protects against improper Notch signaling
4. Viral protein influences key cell-signaling pathway
5. Researchers find promising cancer-fighting power of synthetic cell-signaling molecule
6. Edible bivalves as a source of human pathogens: signals between vibrios and the bivalve host.
7. Scientists discover that three overlapping signals in embryo help get the backbone right
8. After a time-shift, mixed signals from the circadian clock
9. Researchers make surprise discovery that some neurons can transmit three signals at once
10. Structure-building cell signals also may influence learning and memory
11. Fox Chase study shows that weakened T-cell receptor signals change T-cell lineage
Post Your Comments:

(Date:6/20/2016)... , June 20, 2016 Securus Technologies, ... technology solutions for public safety, investigation, corrections and ... prisons involved, it has secured the final acceptance ... facilities for Managed Access Systems (MAS) installed. Furthermore, ... facilities to be installed by October, 2016. MAS ...
(Date:6/9/2016)... Paris Police Prefecture and ... ensure the safety of people and operations in several locations ... Teleste, an international technology group specialised in broadband ... its video security solution will be utilised by ... across the country. The system roll-out is scheduled for the ...
(Date:6/2/2016)... , June 2, 2016   The Weather Company , ... Watson Ads, an industry-first capability in which consumers will be ... able to ask questions via voice or text and receive ... Marketers have long sought an advertising ... that can be personal, relevant and valuable; and can scale ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... June 23, 2016 Houston Methodist Willowbrook ... Cy-Fair Sports Association to serve as their official ... Houston Methodist Willowbrook will provide sponsorship support, athletic ... with association coaches, volunteers, athletes and families. ... Cy-Fair Sports Association and to bring Houston Methodist ...
(Date:6/23/2016)... SAN FRANCISCO , June 23, 2016   ... it has secured $1 million in debt financing from ... to ramp up automation and to advance its drug ... for its new facility. "SVB has been ... goes beyond the services a traditional bank would provide," ...
(Date:6/23/2016)... 23, 2016 Apellis Pharmaceuticals, Inc. today ... trials of its complement C3 inhibitor, APL-2. The ... ascending dose studies designed to assess the safety, ... injection in healthy adult volunteers. Forty ... a single dose (ranging from 45 to 1,440mg) ...
(Date:6/23/2016)... ... June 23, 2016 , ... ... the Pennsylvania Convention Center and will showcase its product’s latest features from June ... be presenting a scientific poster on Disrupting Clinical Trials in The Cloud during ...
Breaking Biology Technology: