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Updated: Jun 25, 2026

High-throughput Screening for Protein-based Inheritance in S. cerevisiae
08:12

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Published on: August 8, 2017

Positive selection in prion protein.

Marko Premzl1, Vera Gamulin

  • 1Department of Molecular Biology, Rudjer Boskovic Institute, Bijenicka 54, 10000, Zagreb, Croatia. mpremzl@irb.hr

Journal of Molecular Evolution
|February 28, 2009
PubMed
Summary
This summary is machine-generated.

Prion protein (PrP) evolution is debated. This study used maximum likelihood tests to detect positive selection in the prion protein gene (PRNP) in humans and cattle, finding evidence of positive selection in specific PrP regions.

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Protein Misfolding Cyclic Amplification of Prions
10:12

Protein Misfolding Cyclic Amplification of Prions

Published on: November 7, 2012

Area of Science:

  • Evolutionary biology
  • Molecular biology
  • Neuroscience

Background:

  • Prion diseases, like Creutzfeldt-Jakob disease and bovine spongiform encephalopathy, are linked to abnormal prion protein (PrP) metabolism and accumulation.
  • The evolutionary history of the prion protein gene (PRNP) is contested, with hypotheses suggesting balancing, purifying, or positive selection.

Purpose of the Study:

  • To investigate the evolutionary pressures on the PRNP gene, specifically at the amino acid level.
  • To test the hypothesis that positive selection has acted on PrP in humans (Euarchonta) and bovines (Laurasiatheria).

Main Methods:

  • Utilized maximum likelihood tests to detect positive selection acting on amino acid changes.
  • Analyzed available PRNP coding sequences from relevant species.

Main Results:

  • Evidence suggests positive selection may have occurred at the amino acid level within the PRNP gene.
  • Specific regions identified include PrP signal sequences, conformationally plastic regions, and protein X binding sites.

Conclusions:

  • The findings contribute to resolving disagreements regarding PRNP evolution.
  • Positive selection likely played a role in shaping specific functional regions of the prion protein in humans and bovines.