Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

It May Take A Mouse to Understand The Behavior of "Jumping Genes"

03.12.2002


Mouse Model May Also Aid In Discovery of Gene Function



Researchers at the University of Pennsylvania School of Medicine have bred a mouse to model human L1 retrotransposons, the so-called "jumping genes." Retrotransposons are small stretches of DNA that are copied from one location in the genome and inserted elsewhere, typically during the genesis of sperm and egg cells. The L1 variety of retrotransposons, in particular, are responsible for about one third of the human genome.

The mouse model of L1 retrotransposition is expected to increase our understanding of the nature of jumping genes and their implication in disease. According to the Penn researchers, the mouse model may also prove to be a useful tool for studying how a gene functions by knocking it out through L1 insertion. Their report is in the December issue of Nature Genetics and currently available online (see below for URL).


"There are about a half million L1 sequences in the human genome, of which 80 to 100 remain an active source of mutation," said Haig H. Kazazian, Jr., MD, Chair of Penn’s Department of Genetics and senior author in the study. "This animal model will help us better understand how this happens, as well as provide a useful tool for discovering the function of known genes."

In humans, retrotransposons cause mutations in germ line cells, such as sperm, which continually divide and multiply. Like an errant bit of computer code that gets reproduced and spread online, retrotransposons are adept at being copied from one location and placed elsewhere in the chromosomes. When retrotransposons are inserted into important genes, they can cause disease, such as hemophilia and muscular dystrophy. On the other hand, retrotransposons have been around for 500 to 600 million years, and have contributed a lot to evolutionary change.

"In the grand scheme of evolution, retrotransposons have behaved like fickle gods, arbitrarily wreaking havoc in some and benefiting others," said Kazazian. "Retrotransposons can cause new genes to emerge that may benefit an organism - or they can kill by knocking out important genes. Overall, however, it seems that they are neutral and add to the apparent sloppiness of the genome."

For some time, researchers have been trying to understand how retrotransposons affect the genome and, in addition, what science may learn from the techniques they employ. According to Kazazian and his colleagues, the mouse model displays high-frequency chromosome to chromosome retrotransposition of human L1s, which behave in exactly the same way as they do in humans. While the current tissue culture model works well, it does not mimic the way retrotransposons jump in chromosomes.

The researchers believe that by understanding the mechanics of retrotransposition, they might be able to use similar techniques for genetic therapies in humans. They also hope to learn more about the basic mysteries behind retrotransposition, such as why L1 retrotransposons only seem to effect the germ line and not any other type of cell in the body.

As science refines the content of the mouse genome database, Kazazian foresees that this model will also be useful for determining the function of different genes. As new genes are identified, their purpose can be resolved by using retrotransposons to knock them out of commission. "Such knowledge has direct impact in humans," said Kazazian, "Information important to determining the nature of human diseases and developing new therapeutics can be extrapolated from our knowledge of the mouse genome."

Funding for this research was provided by grants from the National Institutes of Health.

Greg Lester | EurekAlert!
Further information:
http://www.uphs.upenn.edu/news/

More articles from Life Sciences:

nachricht Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY

nachricht NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Future electronic components to be printed like newspapers

A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.

The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

A smart safe rechargeable zinc ion battery based on sol-gel transition electrolytes

20.07.2018 | Power and Electrical Engineering

Reversing cause and effect is no trouble for quantum computers

20.07.2018 | Information Technology

Princeton-UPenn research team finds physics treasure hidden in a wallpaper pattern

20.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>