Structurally distinct, self-templating prion "strains" can encode distinct phenotypes and amplify at different rates depending upon the environment. Indeed, prion strain ensembles can evolve in response to environmental challenges, which makes them highly challenging drug targets. It is not understood how the proteostasis network amplifies one prion strain at the expense of another. Here, we de...

A well-quasi-order is an order which contains no infinite decreasing sequence and no infinite collection of incomparable elements. In this paper, we consider graph classes defined by excluding one graph as contraction. More precisely, we give a complete characterization of graphs H such that the class of H-contraction-free graphs is well-quasi-ordered by the contraction relation. This result is...

Recently, Choudhury and Metiya [Fixed points of weak contractions in cone metric spaces, Nonlinear Analysis 72 (2010) 1589-1593] proved some fixed point theorems for weak contractions in cone metric spaces. Weak contractions are generalizations of the Banach's contraction mapping, which have been studied by several authors. In this paper, we introduce the notion of $f$-weak contractions and als...

[PSI(+)] is an amyloid-based prion of Sup35p, a subunit of the translation termination factor. Prion "strains" or "variants" are amyloids with different conformations of a single protein sequence, conferring different phenotypes, but each relatively faithfully propagated. Wild Saccharomyces cerevisiae isolates have SUP35 alleles that fall into three groups, called reference, Δ19, and E9, with l...

Yeast prions are protein-based genetic elements that produce phenotypes through self-perpetuating changes in protein conformation. For the prion [PSI(+)] this protein is Sup35, which is comprised of a prion-determining region (NM) fused to a translational termination region. [PSI(+)] strains (variants) with different heritable translational termination defects (weak or strong) can exist in the ...

Abstract In this manuscript we introduce the notion of $(\alpha,\beta,\psi,\phi)$ ( ? , ? ? ? ) -interpolative contraction that unifies and generalizes significant concepts: Proinov type contractions, interpo...