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Protein Misfolding Cyclic Amplification of Prions
10:12

Protein Misfolding Cyclic Amplification of Prions

Published on: November 7, 2012

20.0K

Methionine oxidation within the prion protein

John Bettinger1, Sina Ghaemmaghami1

  • 1Department of Biology, University of Rochester , Rochester, NY, USA.

Prion
|August 4, 2020
PubMed

Insights

Oxidative stress can cause prion protein misfolding. Methionine oxidation by reactive oxygen species (ROS) may initiate prion aggregation, a key step in prion diseases.

Area of Science:

  • Neuroscience
  • Biochemistry
  • Molecular Biology

Background:

  • Prion diseases involve the misfolding of cellular prion protein (PrPC) into infectious PrPSc aggregates.
  • The precise molecular mechanisms driving PrPC misfolding and aggregation are not fully understood.
  • Partially structured intermediates are thought to precede insoluble aggregate formation in prion pathogenesis.

Purpose of the Study:

  • To review the evidence linking methionine oxidation in PrPC to prion formation.
  • To explore the role of reactive oxygen species (ROS) in initiating PrPC destabilization.
  • To understand the contribution of oxidative stress to prion disease mechanisms.

Main Methods:

  • Literature review focusing on prion protein structure and function.
  • Analysis of studies investigating environmental factors affecting PrPC stability.
  • Examination of research on oxidative stress and its impact on protein misfolding.

Main Results:

  • Methionine residues in PrPC are susceptible to oxidation by ROS.
  • Oxidized methionine residues (methionine sulfoxides) can induce PrPC misfolding.
  • This misfolding is a potential critical step in the formation of pathogenic prion aggregates.

Conclusions:

  • Oxidative stress, specifically ROS-mediated methionine oxidation, is a plausible trigger for PrPC misfolding.
  • Understanding methionine oxidation in PrPC is crucial for elucidating prion disease pathogenesis.
  • Targeting oxidative damage may offer therapeutic strategies for prion-related disorders.
Keywords:
Prionsmethionineoxidationprotein aggregationprotein misfolding

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