Featured Research

from universities, journals, and other organizations

Context crucial when it comes to mutations in genetic evolution

Date:
June 13, 2013
Source:
University of Nebraska-Lincoln
Summary:
Evolutionary biologists have found that whether a given mutation is good or bad is often determined by other mutations associated with it. In other words, genetic evolution is context-dependent.

Jay Storz performing field work in the Colorado Rockies.
Credit: Image courtesy of University of Nebraska-Lincoln

With mutations, it turns out that context can be everything in determining whether or not they are beneficial to their evolutionary fate.

According to the traditional view among biologists, a central tenet of evolutionary biology has been that the evolutionary fates of new mutations depend on whether their effects are good, bad or inconsequential with respect to reproductive success. Central to this view is that "good" mutations are always good and lead to reproductive success, while "bad" mutations are always bad and will be quickly weeded out of the gene pool. However, new research led by evolutionary biologist Jay Storz of the University of Nebraska-Lincoln has found that whether a given mutation is good or bad is often determined by other mutations associated with it. In other words, genetic evolution is context-dependent.

In a study to be published in the June 14 issue of Science, Storz and colleagues at UNL and Aarhus University in Denmark report that an individual mutation can be beneficial if it occurs in combination with certain other mutations, but the same mutation can detrimental to the organism if it occurs in other combinations.

The researchers studied mutations that alter the function of hemoglobin, the protein in charge of transporting oxygen in the blood. Physiologists have long known that many high-altitude animals have evolved hemoglobins with high affinities for oxygen, which can enhance oxygen uptake in thin air. Earlier research by Storz's group on populations of North American deer mice that are native to high and low altitudes had found that the high-altitude mice had evolved hemoglobins with an increased oxygen-binding affinity -- and that this difference is attributable to the combined effects of genetic mutations at 12 different sites in the hemoglobin protein.

For the discovery reported in Science, the researchers used a technique called "protein engineering" to synthesize hemoglobin proteins that contained each of the naturally occurring mutations in all possible multi-site combinations.

"By measuring the oxygen-binding properties of these engineered hemoglobins, we discovered that the same individual mutations produced an increased oxygen-affinity in some combinations and they produced a decreased oxygen-affinity in other combinations. Their effects are completely context-dependent," said Storz, an associate professor of biological sciences.

"One of the important implications is that if there are interactions between mutations, then some mutational pathways of evolution may be more accessible than others. The evolutionary fate of a new mutation will depend critically on which other mutations have already occurred. The order in which mutations occur can determine whether evolution is more likely to follow some pathways rather than others. Evolution may follow certain pathways just because certain interactions may be negative, other interactions may be positive. These kinds of interaction effects determine what mutational pathways are open and available for evolution."

Storz's collaborators on the Science paper include Hideaki Moriyama, an associate professor of biological sciences at UNL, and two other researchers in Storz's lab, postdoctoral researcher Chandrasekhar Natarajan and graduate student Noriko Inoguchi; and Roy E. Weber and Angela Fago of Aarhus.

The research was funded by grants from the National Institutes of Health-National Heart, Lung and Blood Institute and the National Science Foundation in the United States, and the Science Faculty, Aarhus University, in Denmark.

It's the fifth time in five years that Storz's research has been published one of the major international interdisciplinary journals. Science is published by the American Association for the Advancement of Science.


Story Source:

The above story is based on materials provided by University of Nebraska-Lincoln. The original article was written by Tom Simons. Note: Materials may be edited for content and length.


Journal Reference:

  1. C. Natarajan, N. Inoguchi, R. E. Weber, A. Fago, H. Moriyama, J. F. Storz. Epistasis Among Adaptive Mutations in Deer Mouse Hemoglobin. Science, 2013; 340 (6138): 1324 DOI: 10.1126/science.1236862

Cite This Page:

University of Nebraska-Lincoln. "Context crucial when it comes to mutations in genetic evolution." ScienceDaily. ScienceDaily, 13 June 2013. <www.sciencedaily.com/releases/2013/06/130613142829.htm>.
University of Nebraska-Lincoln. (2013, June 13). Context crucial when it comes to mutations in genetic evolution. ScienceDaily. Retrieved September 21, 2014 from www.sciencedaily.com/releases/2013/06/130613142829.htm
University of Nebraska-Lincoln. "Context crucial when it comes to mutations in genetic evolution." ScienceDaily. www.sciencedaily.com/releases/2013/06/130613142829.htm (accessed September 21, 2014).

Share This



More Plants & Animals News

Sunday, September 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: San Diego Zoo Welcomes Cheetah Cubs

Raw: San Diego Zoo Welcomes Cheetah Cubs

AP (Sep. 20, 2014) The San Diego Zoo has welcomed two Cheetah cubs to its Safari Park. The nearly three-week-old female cubs are being hand fed and are receiving around the clock care. (Sept. 20) Video provided by AP
Powered by NewsLook.com
Chocolate Museum Opens in Brussels

Chocolate Museum Opens in Brussels

AFP (Sep. 19, 2014) Considered a "national heritage" in Belgium, chocolate now has a new museum in Brussels. In a former chocolate factory, visitors to the permanent exhibition spaces, workshops and tastings can discover derivatives of the cocoa bean. Duration: 01:00 Video provided by AFP
Powered by NewsLook.com
Could Grief Affect The Immune Systems Of Senior Citizens?

Could Grief Affect The Immune Systems Of Senior Citizens?

Newsy (Sep. 19, 2014) The study found elderly people are much more likely to become susceptible to infection than younger adults going though a similar situation. Video provided by Newsy
Powered by NewsLook.com
Jury Delivers Verdict in Salmonella Trial

Jury Delivers Verdict in Salmonella Trial

AP (Sep. 19, 2014) A federal jury has convicted three people in connection with an outbreak of salmonella poisoning five years ago that sickened hundreds of people and was linked to a number of deaths. (Sept. 19) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins