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Updated: Aug 7, 2026
08:12
High-throughput Screening for Protein-based Inheritance in S. cerevisiae
Published on: August 8, 2017
How to find a prion: [URE3], [PSI+] and [beta]
Reed B Wickner1, Herman K Edskes, Frank Shewmaker
1Laboratory of Biochemistry and Genetics, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0830, USA. wickner@helix.nih.gov
Methods (San Diego, Calif.)
|June 24, 2006
Summary
Researchers identified infectious proteins (prions) in microorganisms using genetic methods. These prions, like [URE3] and [PSI(+)], are characterized by their transmissibility and impact on cellular functions.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- Infectious proteins, known as prions, can propagate within microorganisms.
- Prion identification and characterization are crucial for understanding microbial genetics and disease mechanisms.
Purpose of the Study:
- To outline generalizable genetic methods for identifying and diagnosing prions in yeast and other microorganisms.
- To illustrate these methods using well-characterized prions such as [URE3] and [PSI(+)].
Main Methods:
- Utilizing genetic identification applicable to various non-chromosomal genetic elements, including prions.
- Employing cytoduction for transfer and diagnosis of prions.
- Characterizing prions through reversible curability, dependence on protein overproduction, gene requirement for propagation, and phenotypic similarities with mutations.
Main Results:
- Demonstrated the applicability of genetic methods for identifying yeast prions like [URE3] (Ure2p regulator) and [PSI(+)] (Sup35p translation factor).
- Highlighted that the prion concept extends beyond infectious amyloids to include self-activating proteins.
- Detailed methods for studying prions such as [URE3] and the self-activating protease [beta].
Conclusions:
- Genetic methods provide a broadly applicable framework for identifying and studying prions in microorganisms.
- Prions exhibit diverse mechanisms, including amyloid formation and self-activation, impacting cellular processes.
- The described methodologies offer valuable tools for future prion research.
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