Featured Research

from universities, journals, and other organizations

How do polar bears stay warm? Research finds an answer in their genes

Date:
February 10, 2014
Source:
University at Buffalo
Summary:
Among polar bears, only pregnant females den up for the colder months. So how do the rest survive the extreme Arctic winters? New research points to one potential answer: genetic adaptations related to production of nitric oxide, a compound cells use to help convert nutrients into energy or heat.

In the winter, brown and black bears go into hibernation to conserve energy and keep warm. But things are different for their Arctic relative, the polar bear. Within this high-latitude species, only pregnant females den up for the colder months. So how do the rest survive the extreme Arctic winters?

Related Articles


New research points to one potential answer: genetic adaptations related to the production of nitric oxide, a compound that cells use to help convert nutrients from food into energy or heat.

In a new study, a team led by the University at Buffalo reports that genes controlling nitric oxide production in the polar bear genome contain genetic differences from comparable genes in brown and black bears.

"With all the changes in the global climate, it becomes more relevant to look into what sorts of adaptations exist in organisms that live in these high-latitude environments," said lead researcher Charlotte Lindqvist, PhD, UB assistant professor of biological sciences.

"This study provides one little window into some of these adaptations," she said. "Gene functions that had to do with nitric oxide production seemed to be more enriched in the polar bear than in the brown bears and black bears. There were more unique variants in polar bear genes than in those of the other species."

The paper, titled "Polar Bears Exhibit Genome-Wide Signatures of Bioenergetic Adaptation to Life in the Arctic Environment," appeared Feb. 6 in the journal Genome Biology and Evolution. Co-authors include scientists from UB, Penn State University, the U.S.G.S. Alaska Science Center, Durham University and the University of California, Santa Cruz.

The genetic adaptations the research team saw are important because of the crucial role that nitric oxide plays in energy metabolism.

Typically, cells transform nutrients into energy. However, there is a phenomenon called adaptive or non-shivering thermogenesis, where the cells will produce heat instead of energy in response to a particular diet or environmental conditions.

Levels of nitric oxide production may be a key switch triggering how much heat or energy is produced as cells metabolize nutrients, or how much of the nutrients is stored as fat, Lindqvist said.

"At high levels, nitric oxide may inhibit energy production," said Durham University's Andreanna Welch, PhD, first author and a former postdoctoral researcher at UB with Lindqvist. "At more moderate levels, however, it may be more of a tinkering, where nitric oxide is involved in determining whether -- and when -- energy or heat is produced."

The research is part of a larger research program devoted to understanding how the polar bear has adapted to the harsh Arctic environment, Lindqvist said.

In 2012, she and colleagues reported sequencing the genomes of multiple brown bears, black bears and polar bears.

In a paper in the Proceedings of the National Academy of Sciences, the team said comparative studies between the DNA of the three species uncovered some distinctive polar bear traits, such as genetic differences that may affect the function of proteins involved in the metabolism of fat -- a process that's very important for insulation.

In the new study, the scientists looked at the mitochondrial and nuclear genomes of 23 polar bears, three brown bears and a black bear.


Story Source:

The above story is based on materials provided by University at Buffalo. The original article was written by Charlotte Hsu. Note: Materials may be edited for content and length.


Journal Reference:

  1. A. J. Welch, O. C. Bedoya-Reina, L. Carretero-Paulet, W. Miller, K. D. Rode, C. Lindqvist. Polar Bears Exhibit Genome-Wide Signatures of Bioenergetic Adaptation to Life in the Arctic Environment. Genome Biology and Evolution, 2014; DOI: 10.1093/gbe/evu025

Cite This Page:

University at Buffalo. "How do polar bears stay warm? Research finds an answer in their genes." ScienceDaily. ScienceDaily, 10 February 2014. <www.sciencedaily.com/releases/2014/02/140210135826.htm>.
University at Buffalo. (2014, February 10). How do polar bears stay warm? Research finds an answer in their genes. ScienceDaily. Retrieved December 18, 2014 from www.sciencedaily.com/releases/2014/02/140210135826.htm
University at Buffalo. "How do polar bears stay warm? Research finds an answer in their genes." ScienceDaily. www.sciencedaily.com/releases/2014/02/140210135826.htm (accessed December 18, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Thursday, December 18, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

When You Lose Weight, This Is Where The Fat Goes

When You Lose Weight, This Is Where The Fat Goes

Newsy (Dec. 17, 2014) Can fat disappear into thin air? New research finds that during weight loss, over 80 percent of a person's fat molecules escape through the lungs. Video provided by Newsy
Powered by NewsLook.com
The Hottest Food Trends for 2015

The Hottest Food Trends for 2015

Buzz60 (Dec. 17, 2014) Urbanspoon predicts whicg food trends will dominate the culinary scene in 2015. Mara Montalbano (@maramontalbano) has the story. Video provided by Buzz60
Powered by NewsLook.com
Rover Finds More Clues About Possible Life On Mars

Rover Finds More Clues About Possible Life On Mars

Newsy (Dec. 17, 2014) NASA's Curiosity rover detected methane on Mars and organic compounds on the surface, but it doesn't quite prove there was life ... yet. Video provided by Newsy
Powered by NewsLook.com
Ivory Trade Boom Swamps Law Efforts

Ivory Trade Boom Swamps Law Efforts

Reuters - Business Video Online (Dec. 17, 2014) Demand for ivory has claimed the lives of tens of thousands of African elephants and now a conservation report says the illegal trade is overwhelming efforts to enforce the law. Amy Pollock reports. Video provided by Reuters
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:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

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