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Updated: Jun 25, 2026
07:17
Purification of Hsp104, a Protein Disaggregase
Published on: September 30, 2011
Prion proteostasis: Hsp104 meets its supporting cast
Elizabeth A Sweeny1, James Shorter
1Department of Biochemistry and Biophysics, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA.
Prion
|February 27, 2009
Summary
Yeast prions like [PSI+] are protein-based inheritance units that help organisms adapt. Recent research shows chaperone proteins Hsp70:Hsp40 act as a rheostat, fine-tuning Hsp104
Area of Science:
- Molecular Biology
- Protein Folding
- Yeast Genetics
Background:
- The yeast prion [PSI+] is an infectious amyloid form of the release factor Sup35.
- This prion acts as an evolutionary capacitor, revealing genetic variation under stress.
- A proteostasis network, including Hsp104 and Hsp70:Hsp40 chaperones, regulates prion dynamics.
Purpose of the Study:
- To elucidate the cooperative mechanisms of chaperone systems in regulating Sup35 prionogenesis.
- To understand how Hsp70:Hsp40 machinery modulates Hsp104's prion-remodeling activities.
Main Methods:
- Review of recent genetic and biochemical studies on yeast prion regulation.
- Analysis of the interplay between Hsp104, Hsp70, and Hsp40 in prion propagation.
Main Results:
- The Hsp70:Hsp40 chaperone machinery influences the [PSI+] prion cycle.
- This machinery collectively functions as a rheostat, adjusting Hsp104's prion-remodeling functions.
Conclusions:
- The Hsp70:Hsp40 chaperone system provides a regulatory rheostat for Hsp104's prion-modifying activities.
- This regulation is crucial for sustainable Sup35 prionogenesis and the yeast prion cycle.
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