Affordable Access

Publisher Website

Gene Targeting Turns Mice into Long-Distance Runners

PLoS Biology
Public Library of Science
Publication Date
DOI: 10.1371/journal.pbio.0020322
  • Synopsis
  • Bioengineering
  • Biotechnology
  • Cell Biology
  • Development
  • Molecular Biology/Structural Biology
  • Physiology
  • Mus (Mouse)
  • Biology
  • Engineering


PLBI0210_1495-1531.indd PLoS Biology | 1496 October 2004 | Volume 2 | Issue 10 | e322 Open access, freely available online Research Digest Synopses of Research Articles Gene Targeting Turns Mice into Long-Distance Runners DOI: 10.1371/journal.pbio.0020322 Have you ever noticed that long- distance runners and sprinters seem specially engineered for their sports? One’s built for distance, the other speed. The ability to generate quick bursts of power or sustain long periods of exertion depends primarily on your muscle fi ber type ratio (muscle cells are called fi bers), which depends on your genes. To this extent, elite athletes are born, not made. No matter how hard you train or how many performance- enhancing drugs you take, if you’re not blessed with the muscle composition of a sprinter, you’re not going to break the 100-meter world record in your lifetime. (In case you’d like to try, that’s 9.78 seconds for a man and 10.49 seconds for a woman.) Of course that doesn’t prevent those at the highest levels from using the latest performance enhancer to get that extra 1% edge. But wait until trainers hear about the Marathon Mouse. A new study by Ronald Evans and colleagues provides evidence that endurance and running performance can be dramatically enhanced through genetic manipulation. Skeletal muscles come in two basic types: type I, or slow twitch, and type II, or fast twitch. Slow-twitch fi bers rely on oxidative (aerobic) metabolism and have abundant mitochondria that generate the stable, long-lasting supplies of adenosine triphosphate, or ATP, needed for long distance. (For more on muscle fi ber metabolism, see synopsis titled “A Skeletal Muscle Protein That Regulates Endurance”) Fast-twitch fi bers, which produce ATP through anaerobic glycolysis, generate rapid, powerful contractions but fatigue easily. Top-fl ight sprinters have up to 80% type II fi bers while long-distance runners have up to 90% typ

There are no comments yet on this publication. Be the first to share your thoughts.


Seen <100 times