Word: mitochondria
(lookup in dictionary)
(lookup stats)
Dates: all
Sort By: most recent first
(reverse)
Bruce M. Spiegelman, professor of cell biology at HMS, joined researchers at University of Texas-Southwestern in publishing a study in the Aug. 15 issue of Nature demonstrating that the protein PGC-1 can supply certain muscles with the mitochondria that power their contractions...
Easily fatigued type II muscle fibers, known as “fast-twitch” muscles, are fueled by the breakdown of sugar. When the protein is introduced to fatigued type II muscles, it supplies the fibers with the mitochondria they need to produce energy from oxygen...
...mitochondria - cell organelles whose genetic makeup is determined by the mother alone - of all native Europeans except the Sami people of Northern Scandinavia reveal descent from one of what Sykes grandly calls "The Seven Daughters of Eve" (the title, incidentally, of his upcoming book to be published in June). He contends that these ancient matriarchs migrated to Europe from Africa via the Middle East or Asia as long as 50,000 years ago, and he has even assigned evocatively mythical names to each one: Ursula, Helena, Velda, Tara, Katrine, Xenia and Jasmine. He has also delineated rough population histories...
Muscles process oxygen through cellular components known as the mitochondria. Human mitochondria take up only about 3% of the space in a cell. But in animals that run the fastest, mitochondria are far bigger; the mitochondria of an antelope--an animal that easily runs a 2-min. mile and does so in wispy mountain air 7,000 ft. up--are three times larger than ours. "If you could genetically engineer humans to have more mitochondria, bigger hearts and more blood vessels," says Weyand, "we might run about 40 m.p.h...
...likely to tinker with more and more of our genetic machinery, in what may be either mankind's worst folly or the most significant software upgrade of the 21st century. (Caveat emptor, users of version 1.0!) Just last month, biologists announced the discovery of mutations that accumulate in aging mitochondria, which are our cells' batteries; maybe someday they will learn how to keep our batteries from winding down. Scientists may also learn to repair our telo meres, the tiny ties at the ends of each chromosome that help hold our genetic bundles together but fray with age. Researchers may even...