Increasing Prion Propensity by Hydrophobic Insertion
Figure 4
Deletion of tyrosine residues reduces prion formation.
(A) Amino acid sequences of constructs in which tyrosines were deleted from various positions within the Sup35 nucleation domain. Tyrosines are indicated in bold. (B) Western blot of expression levels of wild-type and mutant Sup35s. (C) Prion formation by each construct. Strains expressing the indicated Sup35 mutants as the sole copy of Sup35 were transformed either with an empty vector (left) or with a plasmid expressing the matching Sup35 mutant under control of the GAL1 promoter (right). All strains were cultured for three days in galactose/raffinose dropout medium, and then 10-fold serial dilutions were plated onto medium lacking adenine to select for [PSI+].