title: Estimating the number of prions in yeast cells.
abstract: Certain yeast cells contain proteins that behave like the mammalian prion PrP and are called yeast prions. The yeast prion protein Sup35p can exist in one of two stable forms, giving rise to phenotypes [PSI(+)] and [psi(-)]. If the chemical guanidine hydrochloride (GdnHCl) is added to a culture of growing [PSI(+)] cells, the proportion of [PSI(+)] cells decreases over time. This process is called curing and is due to a failure to propagate the prion form of Sup35p. We describe how curing can be modelled, and improve upon previous models for the underlying processes of cell division and prion segregation; the new model allows for asymmetric cell division and unequal prion segregation. We conclude by outlining plans for future experimentation and modelling.
authors.affiliation: Institute of Mathematics, Statistics, and Actuarial Science, University of Kent, Canterbury, Kent. CT2 7NF, UK. D.J.Cole@kent.ac.uk
authors.forename: D J
authors.initials: DJ
authors.lastname: Cole
authors.forename: B J T
authors.initials: BJ
authors.lastname: Morgan
authors.forename: M S
authors.initials: MS
authors.lastname: Ridout
authors.forename: L J
authors.initials: LJ
authors.lastname: Byrne
authors.forename: M F
authors.initials: MF
authors.lastname: Tuite
mesh_terms: D002455:Cell Division / Q000502:physiology; D003198:Computer Simulation; D019791:Guanidine / Q000494:pharmacology; D008954:Models, Biological; D010454:Peptide Termination Factors; D011328:Prions / Q000502:physiology*; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000502:physiology*; D029701:Saccharomyces cerevisiae Proteins / Q000502:physiology*; D013269:Stochastic Processes
chemical_list: D010454:Peptide Termination Factors; D011328:Prions; C068068:SUP35 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D019791:Guanidine