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Updated: Jun 26, 2026

High-throughput Screening for Protein-based Inheritance in S. cerevisiae
08:12

High-throughput Screening for Protein-based Inheritance in S. cerevisiae

Published on: August 8, 2017

Prion variants and species barriers among Saccharomyces Ure2 proteins

Herman K Edskes1, Lindsay M McCann, Andrea M Hebert

  • 1Laboratory of Biochemistry and Genetics, National Institute of Diabetes Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892-0830, USA.

Genetics
|January 7, 2009
PubMed

Insights

Species barriers prevent prion transmission between yeast species, similar to mammals. Yeast prion domain variations protect against infection, and prion variant traits persist across species.

Area of Science:

  • Yeast genetics and prion biology
  • Comparative genomics and protein evolution

Background:

  • Mammalian prion diseases like scrapie exhibit species barriers due to PrP protein sequence differences.
  • The [URE3] prion in Saccharomyces cerevisiae is caused by the Ure2 protein.
  • Prion domains are crucial for prion formation and propagation.

Purpose of the Study:

  • To investigate the existence and nature of species barriers for the [URE3] yeast prion.
  • To understand the role of Ure2p prion domain sequence variation in interspecies prion transmission.
  • To explore the evolutionary implications of prion domain conservation.

Main Methods:

  • Comparative analysis of Ure2p prion domain sequences across different Saccharomyces species.
  • Assessing [URE3] prion transmission and infectivity between various yeast species.
  • Evaluating the impact of Ure2p sequence variation on prion formation and propagation.

Main Results:

  • Species barriers to [URE3] prion transmission were observed among Saccharomyces species, correlating with Ure2p prion domain sequence differences.
  • Rapid variation in Ure2p prion domains appears to confer protection against prion infection.
  • Some [URE3] prion variants demonstrated interspecies infectivity, while others did not, highlighting prion variant-dependent species barriers.
  • Prion characteristics were maintained even after passage through heterologous Ure2p.
  • Saccharomyces castelli Ure2p, despite having a prion domain, did not form prions or get infected, suggesting its conservation is not solely for prion formation.

Conclusions:

  • Species barriers in yeast prions are influenced by prion variant characteristics, mirroring observations in mammals.
  • Ure2p prion domain sequence variation plays a significant role in modulating interspecies prion transmission.
  • The Ure2p prion domain's conservation may serve functions beyond prion formation, potentially related to its role in nitrogen catabolism regulation.

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