Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

UMass scientist identifies gene that governs obesity, physical activity, sex behaviors in mice

10.12.2002


Findings based on ’knock-out’ mice detailed in the journal Physiology and Behavior



A team led by University of Massachusetts Amherst researcher Deborah J. Good has identified a gene that appears to play a role in obesity, physical activity, and sex behaviors in mice. Good works with so-called "knock-out" mice, which have a specific gene deleted. Scientists then monitor the animals for changes in their physiology and behavior, in an effort to determine the gene’s role. Her findings are detailed in the current issue of the journal Physiology and Behavior. The project is funded with a four-year, $1 million grant from the National Institute of Diabetes and Digestive and Kidney Diseases, and a two-year, $70,000 grant from the National Institute of Child Health and Human Development, both of the National Institutes of Health.

Good is studying the mechanisms in the brain and nervous system that regulate appetite and body weight. Although more than 20 genes have been implicated in the regulation of body weight, the mechanisms through which these genes work remain unclear, she says. Recent evidence by Good suggests that a gene called Nhlh2 plays a key role in the regulation of genes controlling body weight, as well as physical activity levels and mating behavior.


"The knock-out mice can weigh up to 100 grams or more, while most normal mice weigh 25 to 30 grams. Thus, the knock-outs are the equivalent of a 450-pound person," Good says. Two issues contribute to their obesity: the all-too-familiar diet and exercise factors. The mice eat far past what should be the point of satiety, and show a marked disinterest in running on an exercise wheel. "Most mice love to run on a little exercise wheel when you put it in their cage," notes Good, "but not these guys. They run less than other mice before they become obese. Once they do put the extra weight on, their decreased physical activity contributes to their weight gain even more than their food intake."

But these mice can legitimately blame their weight on their genes – or rather, their lack of the Nhlh2 gene. "The gene is responsible for giving them the message, ’You’re full, so stop eating,’ or ’You need to increase your activity, so get some exercise.’" Without Nhlh2, the message is sent but can’t be received on a molecular level, so their body weight continues to increase, Good explains. "It’s as if someone is sending you e-mail, but you’re not reading the message. The message has been sent, but it’s not useful."

"There are humans who have this mutation," notes Good. "If we understand the molecular mechanisms that deal with obesity, perhaps we’ll be able to develop pharmaceuticals for people whose enzyme activity is offset." She also notes that humans can be coached to increase their exercise levels and lower their food intake.

In addition, the gene deletion appears to affect sex behaviors. The knock-out mice have a smaller genital size and lower sperm counts than typical mice. In addition, they show disinterest in mating when they share a cage with a receptive female. (They are able to produce offspring through in vitro methods.) Good cautions that the findings may not be analogous in human beings, in terms of infertility. "We don’t know what would happen in humans," Good says. "There might be fertility problems, but human sex behavior is greatly affected by sociological and cultural expectations that certainly aren’t a factor among mice."

In a related project, Good is studying the molecular control of male reproduction. Although more than 16 specialized proteins are implicated in controlling fertility, the molecular mechanisms of reproduction remain unclear, Good says. She and her team are working toward understanding the molecular control of reproduction and fertility by a specific gene known as Nhlh2.


Note: Deborah Good can be reached at 413/545-5560 or goodd@vasci.umass.edu

Elizabeth Luciano | EurekAlert!
Further information:
http://www.umass.edu/

More articles from Life Sciences:

nachricht Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery
20.01.2017 | GSI Helmholtzzentrum für Schwerionenforschung GmbH

nachricht Seeking structure with metagenome sequences
20.01.2017 | DOE/Joint Genome Institute

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>