Extracellular Vesicles and the Propagation of Yeast Prions

Infectious proteins or prions are self-replicating transmissible aggregates responsible for heritable traits in yeasts and amyloid diseases in mammals. Extensive investigations into the many prions discovered in the yeast Saccharomyces cerevisiae, and most importantly the [PSI⁺] prion, shaped our understanding of the cellular mechanisms involved in amyloidosis. [PSI⁺] arises from the assembly of the translation terminator Sup35p into insoluble fibrillar aggregates leading to nonsense suppression phenotypes. We recently found that infectious Sup35p particles traffic via extracellular (EV) and periplasmic (PV) vesicles in a growth phase and glucose-dependent manner. In this chapter, I will summarize these findings and explain how they fit in current models of yeast prions transmission.