Article

Protein inheritance (prions) based on parallel in-register β-sheet amyloid structures

Laboratory of Biochemistry and Genetics, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0830, USA.
BioEssays (Impact Factor: 4.84). 10/2008; 30(10):955-64. DOI: 10.1002/bies.20821
Source: PubMed

ABSTRACT Most prions (infectious proteins) are self-propagating amyloids (filamentous protein multimers), and have been found in both mammals and fungal species. The prions [URE3] and [PSI+] of yeast are disease agents of Saccharomyces cerevisiae while [Het-s] of Podospora anserina may serve a normal cellular function. The parallel in-register beta-sheet structure shown by prion amyloids makes possible a templating action at the end of filaments which explains the faithful transmission of variant differences in these molecules. This property of self-reproduction, in turn, allows these proteins to act as de facto genes, encoding heritable information.

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