Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study suggests ’noise’ in gene expression could aid bacterial pathogenicity

16.02.2006


Synthetic biology experiment turns up a previously unrecognized gene-expression phenomenon


A high level of variation in the amount of green fluorescence protein in individual non-growing E. coli cells surprised synthetic biology researchers at Boston University and the University of California, San Diego



An experiment designed to show how a usually innocuous bacterium regulates the expression of an unnecessary gene for green color has turned up a previously unrecognized phenomenon that could partially explain a feature of bacterial pathogenicity.

In a paper published in the Feb. 16 issue of Nature, researchers at Boston University (BU) and the University of California, San Diego (UCSD) reported that computer modeling predicted the new phenomenon before they confirmed it in laboratory experiments. The group led by James J. Collins, a biomedical engineering professor at BU, and Jeff Hasty, a bioengineering professor at UCSD, reported that the rise and fall in the amount of green-fluorescence protein in computer modeling matched the pattern recorded in E. coli cells grown in various laboratory conditions.


The researchers were surprised that cell-to-cell variation in the expression of the synthetic gene increased sharply as growth slowed and then stopped. "We were initially skeptical of our own results because they were so counterintuitive," said Collins. "But our laboratory experiments confirmed this increase in gene-expression variability, or noise, when growth stops. We think there may be some very interesting biology to explore in this situation."

Variability in gene expression could offer distinct survival advantages to a bacterium. Like a cruise ship whose life boats have been stocked with different combinations of food, first-aid kits, rain jackets, and flotation devices, a microscopic version of Survivor could occur in which only those individual bacterial cells with opportune combinations of proteins are able to weather harsh growth conditions in a pond or even inside a human body.

"This phenomenon could be relevant to bacterial ’persisters’ - dormant cells that are highly resistant to antibiotics," said Collins. "Many bacterial pathogens can generate these persisters, which over many months can become the source of chronic infections. We don’t understand the how persisters arise, but we think this unexpected gene-expression variability in bacterial cells is an interesting phenomenon that should be explored."

The group of researchers came up with the novel finding by using a relatively new research approach that involves the synthesis of simple gene networks, in this case one that produces a green-fluorescence protein. They measured expression of green fluorescence in a laboratory strain of E. coli under different growth conditions where other genes and proteins could potentially complicate the situation. They incorporated that information into a mathematical model.

The authors say their findings demonstrate the value of a so-called "bottom-up" approach to synthetic biology: models of relatively simple cellular processes can be used to predict the behavior of larger, more complex ones.

"We’re excited by this study because the model itself led to a counterintuitive prediction that was supported by experimentation," said UCSD’s Hasty. "The logical next step is to examine noise in the expression of proteins that would be essential to a bacterium’s survival," Hasty said. "We’ve only begun to get an inkling of how noise in gene expression may be involved in the life of a cell."

Rex Graham | EurekAlert!
Further information:
http://www.ucsd.edu

More articles from Life Sciences:

nachricht New risk factors for anxiety disorders
24.02.2017 | Julius-Maximilians-Universität Würzburg

nachricht Stingless bees have their nests protected by soldiers
24.02.2017 | Johannes Gutenberg-Universität Mainz

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>