Corporate Banner
Satellite Banner
AgriGenomics
Scientific Community
 
Become a Member | Sign in
Home>News>This Article
  News
Return

Rare Form of Active 'Jumping Genes' Found In Mammals

Published: Wednesday, January 09, 2013
Last Updated: Wednesday, January 09, 2013
Bookmark and Share
Johns Hopkins researchers report they have identified a new DNA sequence moving around in bats.

Much of the DNA that makes up our genomes can be traced back to strange rogue sequences known as transposable elements, or jumping genes, which are largely idle in mammals. But Johns Hopkins researchers report they have identified a new DNA sequence moving around in bats — the first member of its class found to be active in mammals. The discovery, described in a report published in December on the website of the Proceedings of the National Academy of Sciences, offers a new means of studying evolution, and may help in developing tools for gene therapy, the research team says.

“Transposable elements are virtually everywhere in nature, from bacteria to humans,” says Nancy Craig, Ph.D., a Howard Hughes investigator and professor in the Johns Hopkins University School of Medicine’s Department of Molecular Biology and Genetics. “They’re often seen as parasites, replicating themselves and passing from generation to generation without doing anything for their hosts. But in fact they play an important role in fueling adaptation and evolution by adding variability to the genome.”

As their name suggests, jumping genes can move from place to place in the genome, sometimes even inserting themselves into the middle of another gene. Some work by replicating themselves and inserting the copies into new places in the genome — retroviruses such as HIV are comprised of this type of jumping gene, which enables the host cell to be hijacked to make more virus particles. Another class of jumping genes, known as “DNA cut-and-paste,” doesn’t make copies, but instead cuts itself out of one site in the genome before hopping into another. Craig explains that in mammal genomes, most jumping genes are of the copy-and-paste variety, and most of these are fossils, mutated to the point where they can no longer move about. Although some remnants of cut-and-paste jumping genes have been unearthed in mammals, until now, all of them have been inactive.

Craig’s team made its discovery while studying piggyBac, an active cut-and-paste jumping gene from insects. PiggyBac got its name because it hitched a ride from one host to another on a virus. While studying how the jumping gene works, the researchers also used computational methods to search for piggyBac-like DNA sequences in the genomes of some species, including that of the little brown bat. There they found a sequence similar to piggyBac, one that didn’t appear to have collected mutations that would make it inactive. Sure enough, near-identical copies were sprinkled throughout the genome, indicating that the sequence had jumped relatively recently. Craig named the find piggyBat. Her team also found that piggyBat can move within bat cells, other mammalian cells and yeast, showing that it is indeed a still-active DNA element.

Many organisms have developed systems to decrease the frequency at which jumping genes move, Craig says. Such systems are a component of immunity, protecting mammals from retroviruses, as well as from the risk that jumping genes will wreak havoc by interrupting an important gene.

Over time, the protective systems have made most mammalian jumping genes inactive. The finding that a bat species is host to an exception, combined with the fact that bats are particularly susceptible to viruses, may indicate that the systems that protect us from dangerous genetic material are not as well-developed in bats, Craig says. But whatever the reason for its presence, piggyBat “opens up a window for studying jumping gene regulation in a mammal where the element is still active,” she says.

This future research should yield insights on the workings of jumping genes themselves, as well as on the protective systems that keep them in check, Craig says. Ultimately, her group hopes to custom-design jumping genes that can be used for targeted, safe and effective gene therapy, delivering genes needed to treat disease.

Other authors on the paper are Rupak Mitra, Ph.D., and Xianghong Lia, Ph.D., of the Johns Hopkins University School of Medicine; Aurélie Kapusta, Ph.D., and Cédric Feschotte, Ph.D., of the University of Utah School of Medicine; and David Mayhew and Robi D. Mitra, Ph.D., of the Washington University School of Medicine in St. Louis.


Further Information

Join For Free

Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 3,100+ scientific posters on ePosters
  • More than 4,500+ scientific videos on LabTube
  • 35 community eNewsletters


Sign In



Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into TechnologyNetworks.com you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.


Scientific News
World’s Largest Coral Gene Database
‘Genetic toolkit’ will help shed light on which species survive climate change.
A Peachy Defense System for Seeds
ETH chemists are developing a new coating method to protect seeds from being eaten by insects. In doing so, they have drawn inspiration from the humble peach and a few of its peers.
Roundup Impacts Gene Expression
Study published on the impact of low-dose toxicity of Roundup weed-killer on gene expression profiles.
Meaningful Part of Maize Genome Defined
FSU-Cornell team show that a small percentage of the maize genome is responsible for 40 percent of a plant’s trait diversity.
Plant Stem Cell Discovery Points to Increased Yields
Braking signals from the leaves tell stem cells to stop proliferating.
Plasma Dose Improves Agricultural Crop Harvests
Researchers at Japan have developed a technique to improve crop yields by treating seeds prior to planting with a safe dose of plasma radiation.
TGAC Installs Largest SGI UV 300 Supercomputer for Life Sciences
The Genome Analysis Centre (TGAC) partners with Global HPC hardware giant SGI to address the most complex problems in genomics analysis.
Carrot Genome Uncovered
Carrot genome paints picture of domestication, could help improve crops.
Flowering Regulation Mechanism Discovered
Monash researchers have discovered a new mechanism that enables plants to regulate their flowering in response to raised temperatures.
Nanoparticles Present Sustainable Way to Grow Food Crops
Nanoparticle technology can help reduce the need for fertilizer, creating a more sustainable way to grow crops such as mung beans.
Skyscraper Banner

SELECTBIO Market Reports
Go to LabTube
Go to eposters
 
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
3,100+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
4,500+ scientific videos
Close
Premium CrownJOIN TECHNOLOGY NETWORKS PREMIUM FOR FREE!