A special set of misfolded proteins known as prions may offer yeast a trial run at different traits before permanent changes are made to the genetic code, a new study finds.
In yeast, prions cause a wide variety of new characteristics that are not wired into DNA but can still be passed on to daughter cells. The changes might act like prototypes that cells can try out before incorporating them into nucleic acid, scientists at the Whitehead Institute for Biomedical Research in Cambridge, Mass. report in the Feb. 16 Nature.
“This is opening up a whole new world of work for scientists and a whole new world for people to understand how evolution occurs,” says Yury Chernoff, a biologist at the Georgia Institute of Technology.
For the most part, prions have attracted attention because some variant forms cause diseases, like Creutzfeldt-Jakob disease in people and scrapie in sheep.