Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Evolvability could be a driving force in drug resistance

10.08.2004


Not only has life evolved, but life has evolved to evolve.



That’s the conclusion drawn by two Rice University scientists who have designed a computer simulation to test the idea that evolvability -- the likelihood of genetic mutation -- is a trait that can itself be favored or disfavored through the process of natural selection.

The results of the study appear in the Aug. 10 issue of Proceedings of the National Academy of Sciences.


Researchers Michael Deem, the John W. Cox Professor of Bioengineering and professor of physics and astronomy, and David Earl, Deem’s post-doctoral research fellow, drew their conclusions from a sophisticated computer simulation that recorded how much and how rapidly proteins mutated based on external changes in their environment. As the researchers ramped up the frequency and severity of environmental changes -- imagine rapid shifts between heat waves and cold snaps or heavy rains and droughts -- they saw an increased likelihood of survival among proteins that mutated more frequently.

"Selection for evolvability would help explain a growing body of experimental results including the evolution of drug resistance in bacteria, the fact that some immune system cells mutate much more rapidly than other cells in our bodies, as well as why some bacteria and higher-order organisms have a tendency to transpose or swap relatively long sequences of DNA," said Deem.

Traditionally, a significant number of evolutionary biologists have discounted the idea that evolvability is subject to natural selection, in part because the idea that evolution acts upon the mechanism that causes evolution seems to violate the basic scientific principle that an event cannot precede its own cause.

But Deem and Earl argue that causal violations need not occur. For one thing, there are several different ways that genetic mutations occur. Random changes along the DNA chain are now understood to be only one way that organisms evolve. Mutations also occur based on genetic recombination, genetic transposition and horizontal gene transfer. With these mechanisms, relatively large chunks of genetic code are shuffled or substituted for one another along the DNA chain.

Deem and Earl’s argument centers on the idea that the ability to reorder genes or to cause large-scale genetic change are themselves genetic traits, traits that are subject to selection like any others.

The upshot of this is that many observations within evolutionary biology that were heretofore considered evolutionary happenstance or accidents, may in fact be explained by selection for evolvability.

Two primary examples of this can be found in the escalating "arms race" that has been documented between pathogens and the immune systems in people and other higher-order vertebrates. Deem and Earl argue that wide variation among bacteria and other antigens has put selective pressure on our immune systems to rapidly adapt methods of identifying and attacking invaders. Similar observations on the rapid mutability among flu viruses and other invading pathogens provide additional evidence, they said.

"The implication is that the drugs we have developed to fight invading pathogens also confer selective pressure on the evolvability of the pathogens themselves," Earl said. "In drug design, it is important to consider this and to look for ways to minimize or counteract this driving force for drug resistence."

Jade Boyd | EurekAlert!
Further information:
http://www.rice.edu

More articles from Health and Medicine:

nachricht Finding new clues to brain cancer treatment
21.02.2020 | Case Western Reserve University

nachricht UIC researchers find unique organ-specific signature profiles for blood vessel cells
18.02.2020 | University of Illinois at Chicago

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

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

Im Focus: A step towards controlling spin-dependent petahertz electronics by material defects

The operational speed of semiconductors in various electronic and optoelectronic devices is limited to several gigahertz (a billion oscillations per second). This constrains the upper limit of the operational speed of computing. Now researchers from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg, Germany, and the Indian Institute of Technology in Bombay have explained how these processes can be sped up through the use of light waves and defected solid materials.

Light waves perform several hundred trillion oscillations per second. Hence, it is natural to envision employing light oscillations to drive the electronic...

Im Focus: Freiburg researcher investigate the origins of surface texture

Most natural and artificial surfaces are rough: metals and even glasses that appear smooth to the naked eye can look like jagged mountain ranges under the microscope. There is currently no uniform theory about the origin of this roughness despite it being observed on all scales, from the atomic to the tectonic. Scientists suspect that the rough surface is formed by irreversible plastic deformation that occurs in many processes of mechanical machining of components such as milling.

Prof. Dr. Lars Pastewka from the Simulation group at the Department of Microsystems Engineering at the University of Freiburg and his team have simulated such...

Im Focus: Skyrmions like it hot: Spin structures are controllable even at high temperatures

Investigation of the temperature dependence of the skyrmion Hall effect reveals further insights into possible new data storage devices

The joint research project of Johannes Gutenberg University Mainz (JGU) and the Massachusetts Institute of Technology (MIT) that had previously demonstrated...

Im Focus: Making the internet more energy efficient through systemic optimization

Researchers at Chalmers University of Technology, Sweden, recently completed a 5-year research project looking at how to make fibre optic communications systems more energy efficient. Among their proposals are smart, error-correcting data chip circuits, which they refined to be 10 times less energy consumptive. The project has yielded several scientific articles, in publications including Nature Communications.

Streaming films and music, scrolling through social media, and using cloud-based storage services are everyday activities now.

Im Focus: New synthesis methods enhance 3D chemical space for drug discovery

After helping develop a new approach for organic synthesis -- carbon-hydrogen functionalization -- scientists at Emory University are now showing how this approach may apply to drug discovery. Nature Catalysis published their most recent work -- a streamlined process for making a three-dimensional scaffold of keen interest to the pharmaceutical industry.

"Our tools open up whole new chemical space for potential drug targets," says Huw Davies, Emory professor of organic chemistry and senior author of the paper.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

70th Lindau Nobel Laureate Meeting: Around 70 Laureates set to meet with young scientists from approx. 100 countries

12.02.2020 | Event News

11th Advanced Battery Power Conference, March 24-25, 2020 in Münster/Germany

16.01.2020 | Event News

Laser Colloquium Hydrogen LKH2: fast and reliable fuel cell manufacturing

15.01.2020 | Event News

 
Latest News

Active droplets

21.02.2020 | Medical Engineering

Finding new clues to brain cancer treatment

21.02.2020 | Health and Medicine

Beyond the brim, Sombrero Galaxy's halo suggests turbulent past

21.02.2020 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>