Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Gene-bender proteins may sway to DNA

06.12.2006
Among the many genes packed into each cell of our body, those that get turned on, or expressed, are the ones that make us who we are. Certain proteins do the job of regulating gene expression by clasping onto key spots of DNA -- the nucleic acid that contains the genetic instructions.

How does the protein recognize a particular binding site" Structural changes in both the protein and DNA, sometimes with the DNA within the complex kinked or sharply bent, allow for the specific contacts needed for a tight DNA-protein fit.

Scientists think DNA is largely passive in this genetic tango. But new findings by Anjum Ansari, associate professor of biophysics at the University of Illinois at Chicago, suggest DNA may not be the wallflower that many had assumed.

To follow in real time the structural changes that accompany protein-DNA binding, Ansari and her UIC colleagues used a test protein from bacteria and applied a laser pulse lasting about 10 billionths of a second to heat up and disturb the protein-DNA complex. They watched the dynamics of the bound DNA in response to this perturbation.

... more about:
»Ansari »DNA »Interaction »Protein-DNA

Ansari's group was the first to apply the laser temperature-jump technique to study the dynamics of a protein-DNA complex.

The studies were done in collaboration with Donald Crothers, Sterling Professor Emeritus of chemistry at Yale University, who examined the protein-DNA interaction with the more traditional stopped-flow technique.

"While stopped-flow technique can capture dynamics of biomolecules occurring on millisecond time-scales or longer, the goal of this study was to extend the time-resolution down to sub-microseconds. It gave us a new time window on probing protein-DNA interactions," Ansari said.

That broader time window, obtained in combination with the stopped-flow measurements, provided the first direct observation of DNA bending when bound to a DNA-bending protein.

"We found that the time-scales on which DNA was bending were very similar to previously reported time-scales on which individual base-pairs that hold the two DNA strands together were transiently breaking. That led us to conclude that the DNA is able to bend or kink on its own, at weak points created by the transient opening of base-pairs, and that the protein recognizes and binds tightly to the bent DNA conformation."

Conclusions by Ansari and her colleagues deviate slightly from the conventional dogma that it is the protein that bends the DNA. She said the results raise important questions about the role that the DNA "bendability" plays in guiding the correct bending protein to the appropriate site on the DNA.

Ansari said the research adds to the basic understanding of how proteins recognize a specific binding site.

"Gaining better insights into protein-DNA interactions that control all aspects of gene regulation may prove useful for rational design of drugs to target specific sites on the DNA, whereby one can ultimately develop better gene-based therapies," she said.

Paul Francuch | EurekAlert!
Further information:
http://www.earthlink.net
http://www.uic.edu/index.html/

Further reports about: Ansari DNA Interaction Protein-DNA

More articles from Life Sciences:

nachricht Warming ponds could accelerate climate change
21.02.2017 | University of Exeter

nachricht An alternative to opioids? Compound from marine snail is potent pain reliever
21.02.2017 | University of Utah

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

Impacts of mass coral die-off on Indian Ocean reefs revealed

21.02.2017 | Earth Sciences

Novel breast tomosynthesis technique reduces screening recall rate

21.02.2017 | Medical Engineering

Use your Voice – and Smart Homes will “LISTEN”

21.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>