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Related Experiment Video

Updated: Dec 8, 2025

Protein Misfolding Cyclic Amplification of Prions

Protein Misfolding Cyclic Amplification of Prions

Published on: November 7, 2012

Cofactor molecules: Essential partners for infectious prions.

Surachai Supattapone¹

¹Department of Biochemistry and Cell Biology and Department of Medicine, Geisel School of Medicine at Dartmouth College, Hanover, NH, United States.

Progress in Molecular Biology and Translational Science

|September 22, 2020

Summary

Infectious prions require cofactors like RNA and phosphatidylethanolamine, challenging the protein-only hypothesis. These cofactors are essential for prion infectivity and influence prion strain properties.

Keywords:

Cofactor Cofactor selection Mammalian Phosphatidylethanolamine Phospholipid Polyanion Prion RNA Specific infectivity

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Area of Science:

Neuroscience
Biochemistry
Molecular Biology

Background:

The protein-only hypothesis suggests prions consist solely of misfolded PrPSc.
Wild-type protein-only PrPSc preparations typically lack significant prion infectivity.

Purpose of the Study:

To investigate the role of cofactors in prion formation and infectivity.
To challenge the protein-only hypothesis by identifying essential non-protein components.

Main Methods:

Systemic biochemical approach to isolate and identify endogenous cofactor molecules.
Experimental manipulation of cofactor molecules to assess their impact on prion infectivity and strain properties.

Main Results:

Identified RNA and phosphatidylethanolamine as endogenous cofactors facilitating high-specific-infectivity prion formation.
Demonstrated that purified cofactor molecules restrict the strain properties of infectious prions.
Proposed a "cofactor selection" model to explain strain-dependent neurotropism.

Conclusions:

Cofactor molecules are required for the formation of wild-type infectious prions.
The distribution of strain-specific cofactors may determine prion neurotropism patterns.
The protein-only hypothesis is insufficient to explain prion infectivity and strain diversity.