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 For a chimpanzee, one good turn deserves another
27.06.2017 | Max-Planck-Institut für Mathematik in den Naturwissenschaften (MPIMIS)

nachricht New method to rapidly map the 'social networks' of proteins
27.06.2017 | Salk 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: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Touch Displays WAY-AX and WAY-DX by WayCon

27.06.2017 | Power and Electrical Engineering

Drones that drive

27.06.2017 | Information Technology

Ultra-compact phase modulators based on graphene plasmons

27.06.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>