Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

NYU biologists find new function for pacemaker neurons

26.01.2005


A study by New York University researchers reveals a new function for the nerve cells that regulate circadian rhythms of behavior in fruit flies.



The nerve cells, called pacemaker neurons, contain a molecular clock that controls a 24-hour circadian rhythm in activity similar to the rhythms in sleep/wake cycles found in humans and many other organisms. It was previously known that pacemaker neurons receive visual signals to reset their molecular clocks, but scientists did not have any evidence that they transmitted information to their target cells, as most other neurons do.

The current study shows that pacemaker neurons do in fact transmit signals and are required for a rapid behavior, according to the paper, published in the January 20th issue of Neuron. The study was conducted by Esteban O. Mazzoni, a graduate student in NYU’s Biology Department, Biology Professor Claude Desplan, and Assistant Biology Professor Justin Blau. The finding suggests it may be possible to identify genes that can be used to treat problems such as sleep disorders and jet lag.


The researchers examined the role that pacemaker neurons play in helping Drosophila larvae avoid light. Drosophila is a species of fruit fly commonly used in biological research. Fruit fly larvae foraging for food avoid light, presumably to keep away from predators. Unlike adult Drosophila, the larvae only have one structure for gathering visual cues, called Bolwig’s Organ. This organ senses the amount of light in the environment and transmits that information to the pacemaker neurons to reset their molecular clocks.

In the experiments described by Mazzoni, Desplan, and Blau, fly larvae were placed in the center of a Petri dish with one side dark and the other illuminated. Normal larvae exhibited the natural behavior and clustered on the dark side. However, when the larvae had their pacemaker neurons disabled, they were as blind as larvae that had their light-sensing organs removed and distributed themselves evenly between the light and dark halves of the Petri dish.

Further experiments showed that, in addition to transmitting the light information, the pacemaker neurons also modulate the sensitivity of larvae to light, generating a circadian rhythm in visual sensitivity. The experiments revealed that fruit fly larvae are most sensitive to light at dawn and least sensitive toward dusk.

The study demonstrates that pacemaker neurons are doing much more than scientists had suspected. They not only relay visual signals to target cells, but are also act as filters, using their molecular clocks to adjust the intensity of the transmitted signal depending on the time of day.

Almost all of the genes that make up Drosophila’s molecular clock have counterparts with similar functions in mammals. Because of this similarity, it may be possible to identify genes in fruit flies that can be used to treat problems in people, such as sleep disorders and jet lag.

James Devitt | EurekAlert!
Further information:
http://www.nyu.edu

More articles from Studies and Analyses:

nachricht Innovative genetic tests for children with developmental disorders and epilepsy
11.07.2018 | Christian-Albrechts-Universität zu Kiel

nachricht Oxygen loss in the coastal Baltic Sea is “unprecedentedly severe”
05.07.2018 | European Geosciences Union

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

Im Focus: Chemical reactions in the light of ultrashort X-ray pulses from free-electron lasers

Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.

Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

Microscopic trampoline may help create networks of quantum computers

17.07.2018 | Information Technology

In borophene, boundaries are no barrier

17.07.2018 | Materials Sciences

The role of Sodium for the Enhancement of Solar Cells

17.07.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>