Nucleation seed size determines amyloid clearance and establishes a barrier to prion appearance in yeast.

Amyloid appearance is a rare event that is promoted in the presence of other aggregated proteins. These aggregates were thought to act by templating the formation of an assembly-competent nucleation seed, but we find an unanticipated role for them in enhancing the persistence of amyloid after it arises. Specifically, Saccharomyces cerevisiae Rnq1 amyloid reduces chaperone-mediated disassembly of Sup35 amyloid, promoting its persistence in yeast.

Inhibition of endocytic pathways impacts cytomegalovirus maturation.

Endocytic processes are critical for cellular entry of several viruses; however, the role of endocytosis in cellular trafficking of viruses beyond virus entry is only partially understood. Here, we utilized two laboratory strains (AD169 and Towne) of human cytomegalovirus (HCMV), which are known to use cell membrane fusion rather than endocytosis to enter fibroblasts, in order to study a post-entry role of endocytosis in HCMV life cycle. Upon pharmacological inhibition of dynamin-2 or clathrin terminal domain (TD) ligand association, these strains entered the cells successfully based on the expression of immediate early viral protein.

Highly acidic C-terminal region of cytomegalovirus pUL96 determines its functions during virus maturation independently of a direct pp150 interaction.

Unlabelled: Tegument proteins pp150 and pUL96 function at a late step in cytomegalovirus (CMV) maturation. Here, we show that pp150 interacts directly with pUL96; however, the N-terminal region of pp150 and the C-terminal region of pUL96, which are critical for these proteins to function, are not required for this interaction. Moreover, the largely dispensable C-terminal region of pp150 is critical for pp150-pUL96 interaction.

Complete Genome Sequence of a UL96 Mutant Cytomegalovirus Towne-BAC (Bacterial Artificial Chromosome) Isolate Passaged in Fibroblasts To Allow Accumulation of Compensatory Mutations.

Here, we present the complete genome sequence of a cytomegalovirus Towne-BAC (bacterial artificial chromosome) isolate that we first genetically engineered to mutate the UL96 gene and then serially passaged in human fibroblasts to allow for the accumulation of compensatory mutations. A total of 17 single-base substitutions were discovered in the passaged genome compared to the reference sequence (KF493877).