Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Cells use 'noise' to make cell-fate decisions

23.03.2007
Electrical noise, like the crackle heard on AM radio when lightning strikes nearby, is a nuisance that wreaks havoc on electronic devices. But within cells, a similar kind of biochemical "noise" is beneficial, helping cells transform from one state to another, according to a new study led by a UT Southwestern Medical Center researcher.

Dr. Gürol Süel, assistant professor of pharmacology, said his research and that of his colleagues published today in the journal Science represents "a new paradigm," suggesting that rather than being bad for biology, cellular noise might have an important function, such as prompting stem cells to transform into a specific tissue type.

Electronic noise is an unwanted signal characteristic of all electrical circuits, typically caused by random fluctuations in the electric current passing through the components of a circuit. Similarly, within each living cell there are myriad "genetic circuits," each composed of a distinct set of biochemical reactions that contribute to some biological process. Randomness in those reactions contributes to biological noise, technically referred to as stochastic fluctuations.

"Noise in biological systems is a fact of life," said Dr. Süel, a member of the systems biology division of the Cecil H. and Ida Green Comprehensive Center for Molecular, Computational and Systems Biology at UT Southwestern. "Even though each cell may have the same set of genes turned on – the same hard-wired genetic circuit – there will still be slight variations in the amount of the various proteins those genes produce, some fluctuation in the amount of each circuit component. No two cells are alike in terms of their chemical composition."

Conventional scientific thinking has been that the random nature of such fluctuations within cells interferes with the reliable operation of biological systems. However, Dr. Süel's research team hypothesized that noise in one particular genetic circuit might be beneficial, linked to a process that controls cell fate.

To determine the biological role for noise, the researchers analyzed a genetic circuit that controls the transformation of bacteria cells from one state to another. This process, called differentiation, is akin to that used by human stem cells to change into a specific tissue type.

In a series of theoretical calculations and actual experiments, the researchers found that the particular circuit they investigated appears to have evolved in this bacterium to amplify cellular noise. Dr. Süel and his colleagues determined that by dampening the noise level within the bacterial cells, they could prevent the cells' transformation between states, essentially "tuning" cellular behavior.

"The amplitude of cellular noise correlates with the probability of triggering differentiation," Dr. Süel said. "This is experimental evidence that a genetic circuit utilizes noise to drive a biological process."

Typically, scientists examine genes and proteins individually to try to determine their functions within a cell. However, Dr. Süel said that's like examining each capacitor or switch in an electrical circuit in an attempt to understand the function of the electrical device in which the circuit is housed.

"Our research provides a systems-level view of how gene circuits work as a whole," he said.

Dr. Süel said the next step in his research would be to uncover the theoretical design principles of genetic circuits and what role interactions between distinct circuits play in regulating complex biological processes, such the differentiation of multipotent stem cells.

Dr. Süel, who earned his doctorate in molecular biophysics from UT Southwestern, carried out much of the work for the Science paper while a postdoctoral research fellow at the California Institute of Technology. He joined the UT Southwestern faculty in November and is an Endowed Scholar in Biomedical Research.

Other co-authors on the Science paper are Rajan Kulkarni and senior author Michael Elowitz, both of Caltech; Jonathan Dworkin of Columbia University; and Jordi Garcia-Ojalvo of the Universitat Politecnica de Catalunya in Spain.

The work was funded in part by the National Institutes of Health, the Searle Scholars Program and the Human Frontier Science Program.

Amanda Siegfried | EurekAlert!
Further information:
http://www.utsouthwestern.edu

Further reports about: Fluctuation Science Süel biological process biological system

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

3rd Symposium on Driving Simulation

23.10.2017 | Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

 
Latest News

Taming 'wild' electrons in graphene

23.10.2017 | Physics and Astronomy

Mountain glaciers shrinking across the West

23.10.2017 | Earth Sciences

Scientists track ovarian cancers to site of origin: Fallopian tubes

23.10.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>