CAMBRIDGE, Mass. (April 2, 2009) Whitehead Institute researchers have quintupled the number of identifiable prion proteins in yeast and have further clarified the role prions play in the inheritance of both beneficial and detrimental traits.
"The big debate in the field is are the prions functional are they evolved to be prions, or are they always a disease, as in "mad cow'" disease in mammals," says Randal Halfmann, a research assistant in Whitehead Member Susan Lindquist's lab, and coauthor of the paper featured on the cover of the April 3 issue of the journal Cell. "We wanted to find more prions and see what they're doing, so we could answer that question."
The Lindquist lab's work further alters the way researchers view prions, from biological anomalies to mediators of trait inheritance and adaptations to fluctuating environments. work shifts the way researchers view prions, from being a biological anomaly to a key
Prions' bad reputation was fixed in the public's mind by "mad cow" disease. In the late 1980s, an unidentified disease infected more than 100,000 British cows and spread to humans, eventually killing more than 200 people. The disease causes progressive degeneration of physical and mental abilities, which ultimately lead to death.
Scientists found the infectious agent was a prion, a misfolded version of the PrP protein found clumped together in brain cells. Brain matter in PrP-infected animals takes on a spongy appearance, lending the condition its formal name, bovine spongiform encephalitis (BSE).
Unlike other proteins, the misfolded PrP protein is transmissible. When the misfolded PrP protein is introduced to healthy cells, it can convert normally-folded PrP proteins to its misfolded shape and cause a clumping cascade characteristic of prions.
Over the years, researchers have identified a small number of other prions in humans and other animals, most of which cause degenerative
|Contact: Nicole Giese|
Whitehead Institute for Biomedical Research