De novo prions
نویسندگان
چکیده
Prions are responsible for a heterogeneous group of fatal neurodegenerative diseases. They occur in three forms - sporadic, genetic, or acquired - and involve non-covalent post-translational modifications of the cellular prion protein (PrP(C)). Prions (PrP(Sc)) are characterized by their infectious properties and intrinsic ability to act as a template, converting the normal, physiological PrP(C) into the pathological form, PrP(Sc). The 'protein-only' hypothesis, postulated by Stanley B Prusiner, implies that the generation of de novo prions is possible. Exciting recent work, in vivo and in vitro, has further strengthened this postulate.
منابع مشابه
Cellular factors important for the de novo formation of yeast prions.
Prions represent an unusual structural form of a protein that is 'infectious'. In mammals, prions are associated with fatal neurodegenerative diseases such as CJD (Creutzfeldt-Jakob disease), while in fungi they act as novel epigenetic regulators of phenotype. Even though most of the human prion diseases arise spontaneously, we still know remarkably little about how infectious prions form de no...
متن کاملInteractions among prions and prion "strains" in yeast.
Prions are "infectious" proteins. When Sup35, a yeast translation termination factor, is aggregated in its [PSI(+)] prion form its function is compromised. When Rnq1 is aggregated in its [PIN(+)] prion form, it promotes the de novo appearance of [PSI(+)]. Heritable variants (strains) of [PSI(+)] with distinct phenotypes have been isolated and are analogous to mammalian prion strains with differ...
متن کاملDe Novo Generation of a Unique Cervid Prion Strain Using Protein Misfolding Cyclic Amplification
Substantial evidence supports the hypothesis that prions are misfolded, infectious, insoluble, and protease-resistant proteins (PrPRES) devoid of instructional nucleic acid that cause transmissible spongiform encephalopathies (TSEs). Protein misfolding cyclic amplification (PMCA) has provided additional evidence that PrPRes acts as a template that can convert the normal cellular prion protein (...
متن کاملAnimal Prions Are a New Type of Infectious Agents Prions
Prions were originally defined as infectious agents of protein nature, which caused neurodegenerative diseases in animals and humans. The prion concept implies that the infectious agent is a protein in special conformation that can be transmitted to the normal molecules of the same protein through protein–protein interactions. Until the 1990s, the prion phenomenon was associated with the single...
متن کاملPrions Affect the Appearance of Other Prions The Story of [PIN+]
Prions are self-propagating protein conformations. Recent research brought insight into prion propagation, but how they first appear is unknown. We previously established that the yeast non-Mendelian trait [PIN(+)] is required for the de novo appearance of the [PSI(+)] prion. Here, we show that the presence of prions formed by Rnq1 or Ure2 is sufficient to make cells [PIN(+)]. Thus, [PIN(+)] ca...
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