Oligopeptide repeats appear in many proteins that undergo conformational conversions to form amyloid, including the mammalian prion protein PrP and the yeast prion protein Sup35. Whereas the repeats in PrP have been studied more exhaustively, interpretation of these studies is confounded by the fact that many details of the PrP prion conformational conversion are not well understood. On the oth...

The study of fungal prion proteins affords remarkable opportunities to elucidate both intragenic and extragenic effectors of prion propagation. The yeast prion protein Sup35 and the self-perpetuating [PSI+] prion state is one of the best characterized fungal prions. While there is little sequence homology among known prion proteins, one region of striking similarity exists between Sup35p and th...

Prion-like proteins can undergo conformational rearrangements from an intrinsically disordered to a highly ordered amyloid state. This ability to change conformation is encoded in distinctive domains, termed prion domains (PrDs). Previous work suggests that PrDs change conformation to affect protein function and create phenotypic diversity. More recent work shows that PrDs can also undergo many...

Yeasts contain various protein-based genetic elements, termed prions, that result from the structural conversion of proteins into self-propagating amyloid forms. Most yeast prion proteins contain glutamine/asparagine (Q/N)-rich prion domains that drive prion activity. Here, we explore two mechanisms by which new prion domains could evolve. First, it has been proposed that mutation and natural s...

Prions are self-propagating protein conformations. Transmission of the prion state between non-identical proteins, e.g. between homologous proteins from different species, is frequently inefficient. Transmission barriers are attributed to sequence differences in prion proteins, but their underlying mechanisms are not clear. Here we use a yeast Rnq1/[PIN(+)]-based experimental system to explore ...

The [URE3] and [PSI(+)] prions are the infections amyloid forms of the Saccharomyces cerevisiae proteins Ure2p and Sup35p, respectively. Randomizing the order of the amino acids in the Ure2 and Sup35 prion domains while retaining amino acid composition does not block prion formation, indicating that amino acid composition, not primary sequence, is the predominant feature driving [URE3] and [PSI...

Amyloid protein aggregation is a key factor in the development of variety serious diseases humans, commonly named as amyloidoses (Alzheimers and Parkinsons diseases, type II diabetes, etc.), determinant protein-based inheritance lower eukaryotes. In yeast, translation termination Sup35 one most extensively studied amyloidogenic proteins. Aggregation (induction [PSI+] prion) decreases its functi...

Prion diseases, or transmissible spongiform encephalopathies (TSEs), are infectious fatal neurodegenerative disorders that include a variety of human diseases, such as CreutzfeldtJacob disease (CJD), Gerstmann-Sträussler-Scheinker syndrome (GSS), kuru and fatal familial insomnia [1, 2]. Mammalian prion protein (PrP) in an abnormal aggregation-prone selfperpetuating (prion) conformation has been...

Prion diseases are invariably fatal and highly infectious neurodegenerative diseases affecting humans and animals. The neurodegenerative diseases such as CreutzfeldtJakob disease, variant Creutzfeldt-Jakob diseases, Gerstmann-Sträussler-Scheinker syndrome, Fatal Familial Insomnia, Kuru in humans, scrapie in sheep, bovine spongiform encephalopathy (or mad-cow disease) and chronic wasting disease...

Prions are a self-templating amyloidogenic state of normal cellular proteins, such as prion protein (PrP). They have been identified as the pathogenic agents, contributing to a number of diseases of the nervous system. However, the discovery that the neuronal RNA-binding protein, cytoplasmic polyadenylation element-binding protein (CPEB), has a prion-like state that is involved in the stabiliza...