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Anti-Prion Systems in Yeast and Inositol Polyphosphates
Reed B Wickner1, Evgeny E Bezsonov1, Moonil Son1
1Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health , Bethesda, Maryland 20892-0830, United States.
Biochemistry
|January 30, 2018
Summary
Yeast prions, amyloid polymers, are influenced by inositol polyphosphates. These molecules are crucial for [PSI+] prion propagation and may offer therapeutic targets for amyloid diseases.
Area of Science:
- Molecular Biology
- Prion Biology
- Biochemistry
Background:
- Yeast prions are self-propagating amyloid polymers with diverse conformations.
- Cells possess anti-prion systems that regulate prion formation, curing, and pathology.
- Siw14p, a pyrophosphatase, is involved in anti-prion activity.
Purpose of the Study:
- To investigate the role of inositol polyphosphates in yeast prion propagation.
- To understand the anti-prion mechanisms involving Siw14p.
Main Methods:
- Studied the anti-prion activity of Siw14p.
- Investigated the effect of inositol polyphosphates on [PSI+] prion variants.
Main Results:
- Inositol polyphosphates, including inositol hexakisphosphate, 5PP-IP4, and 5PP-IP5, are essential for the propagation of most [PSI+] prion variants.
- Siw14p's pyrophosphatase activity is linked to inositol polyphosphate metabolism and anti-prion function.
Conclusions:
- Inositol polyphosphates are critical regulators of yeast prion ([PSI+]) propagation.
- Yeast prions serve as models for mammalian amyloid diseases, suggesting potential therapeutic avenues targeting inositol polyphosphate pathways.
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