A yeast prion provides a mechanism for genetic variation and phenotypic diversity

@article{True2000AYP,
  title={A yeast prion provides a mechanism for genetic variation and phenotypic diversity},
  author={Heather L. True and Susan Lindquist},
  journal={Nature},
  year={2000},
  volume={407},
  pages={477-483}
}
A major enigma in evolutionary biology is that new forms or functions often require the concerted effects of several independent genetic changes. It is unclear how such changes might accumulate when they are likely to be deleterious individually and be lost by selective pressure. The Saccharomyces cerevisiae prion [PSI+] is an epigenetic modifier of the fidelity of translation termination, but its impact on yeast biology has been unclear. Here we show that [PSI+] provides the means to uncover… 
Epigenetic regulation of translation reveals hidden genetic variation to produce complex traits
TLDR
[PSI+] expands the conceptual framework for phenotypic plasticity, provides a one-step mechanism for the acquisition of complex traits and affords a route to the genetic assimilation of initially transient epigenetic traits.
Prion Switching in Response to Environmental Stress
TLDR
The hypothesis that [PSI+] is a mechanism to increase survival in fluctuating environments and might function as a capacitor to promote evolvability is supported.
Prions are a common mechanism for phenotypic inheritance in wild yeasts
TLDR
Biochemically test approximately 700 wild strains of Saccharomyces for [PSI+] or [MOT3+], and find these prions in many, and they conferred diverse phenotypes that were frequently beneficial under selective conditions.
Prion-mediated diversity in yeast
  • Rowley
  • Biology
    Trends in genetics : TIG
  • 2000
Does the central dogma still stand?
TLDR
There is non-negligible flow of information from proteins to the genome in modern cells, in a direct violation of the Central Dogma of molecular biology.
Prions as protein-based genetic elements.
TLDR
The ability to become a prion appears to be evolutionarily conserved in two cases, and [PSI(+)] provides a mechanism for genetic variation and phenotypic diversity in response to changing environments.
THE EVOLUTION OF THE EVOLVABILITY PROPERTIES OF THE YEAST PRION [PSI+]
TLDR
It is found that evolvability is a more likely explanation, as long as environmental change makes partial read-through of stop codons adaptive at a frequency of at least once every million years.
Epigenetic regulation of genome integrity by a prion-based mechanism
TLDR
[MPH1+] provides resistance to DNA damage, a gain-of-function trait that requires helicase activity and interactions with other DNA repair proteins, and fuels a quasi-Lamarckian form of inheritance that promotes survival of the current generation and diversification of the next.
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TLDR
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TLDR
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TLDR
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TLDR
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