Tip A third mechanism of evolution

[Diane]

Prions point to a new style of evolution

..'protein mutations', or prions, have a strong impact on [the physical appearance of an organism], so not all evolution is occurring through a DNA change

...at least in yeast.

[Diane]

More about the topic: Prions and chaperones: Outside the fold

Lindquist's... work over the past 20 years has consistently challenged standard thinking on evolution, inheritance and the humble yeast. She has helped to show how misfolded infectious proteins called prions can override the rules of inheritance in yeast, and how this can be used to model human disease. She has also proposed a mechanism by which organisms can unleash hidden variation and evolve by leaps and bounds. She was the first female director of the prestigious Whitehead Institute for Biomedical Research in Cambridge, Massachusetts, and has received more than a dozen awards and honours in the past five years. In a paper being published this week in Nature, she and her colleagues show that in wild yeast, prions provide tangible advantages, such as survival in harsh conditions and drug resistance1.