Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Light, circadian rhythms affect vast range of physiological, behavioral functions

27.08.2010
A new study of the genetic basis of circadian rhythms – the biological responses related to daily light exposure – has found that a few minutes of light exposure in a fungus directly affects a huge range of its biological functions, everything from reproduction to coloring and DNA repair.

Prior to this, five “DNA binding sites” in this fungus were known to be responsible for gene activation by light exposure. Through advanced “high throughput” DNA sequencing, researchers discovered that light actually affects not just a few but more than 300 binding sites, ultimately controlling 2,500 of the 10,000 genes in the fungus Neurospora crassa.

The research, done by four universities in the U.S. and Germany, has revealed for the first time how specific metabolic pathways can be directly activated by light in this fungus, which has long served as a model to understand gene regulation by light, and circadian rhythms in animals and humans.

“You have one factor, light exposure, to start with,” said Michael Freitag, an assistant professor of biochemistry and biophysics at Oregon State University. “In just a few minutes, this turns on genetic mechanisms that influence everything from spore development to stress response, pigmentation, carbon metabolism, the cell cycle, nitrogen regulation, DNA repair and many other functions.”

This new research shows that light exposure affects 24 “transcription factors” that function as master genetic regulators, which in turn activate dozens of other genes that control everything from behavior to physiology in this fungus. For instance, if the fungus is grown in the dark, it will be white – but with just two minutes of exposure to light, it turns orange and stays that way permanently, its gene for pigmentation having been activated.

Although not all of the genes involved are identical, many genes perform similar functions in humans, Freitag said, and the effect of light exposure on human metabolism is probably more similar to than different from this fungus.

Researchers are continuing to learn more about the phenomenal scope of biological and metabolic functions that are related to light and the natural rhythms of day and night. Disruptions in these rhythms can have a significant range of physical and health effects, scientists have found.

This fungus, Neurospora, has been studied for decades in genetic research, along with other model systems such as fruit flies, laboratory rodents and other models. It was first identified as a “red bread mold” in the 1800s and studied by the famous French microbiologist Louis Pasteur, and is still especially useful for research on circadian rhythms and gene regulation.

The research was published in Eukaryotic Cell, a professional journal, in work supported by the National Institutes of Health, National Science Foundation, and the American Cancer Society. Collaborators on the study were from OSU, the University of California/Berkeley, University of California/Riverside, and the laboratories of Deborah Bell-Pedersen at Texas A&M University and Michael Brunner at Universität Heidelberg.

“Light signaling pathways and circadian clock are inextricably linked and have profound effects on behavior in most organisms,” the researchers wrote in their study. “Our findings provide links between the key circadian activator and effectors in downstream regulatory pathways.”

About the OSU College of Science: As one of the largest academic units at OSU, the College of Science has 14 departments and programs, 13 pre-professional programs, and provides the basic science courses essential to the education of every OSU student. Its faculty are international leaders in scientific research.

Michael Freitag | EurekAlert!
Further information:
http://www.oregonstate.edu

More articles from Studies and Analyses:

nachricht The personality factor: How to foster the sharing of research data
06.09.2017 | ZBW – Leibniz-Informationszentrum Wirtschaft

nachricht Europe’s Demographic Future. Where the Regions Are Heading after a Decade of Crises
10.08.2017 | Berlin-Institut für Bevölkerung und Entwicklung

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: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>