Specificity of prion assembly in vivo. [PSI+] and [PIN+] form separate structures in yeast.
The yeast prions [PSI+] and [PIN+] are self-propagating amyloid aggregates of the Gln/Asn-rich proteins Sup35p and Rnq1p, respectively. Like the mammalian PrP prion "strains," [PSI+] and [PIN+] exist in different conformations called variants. Here, [PSI+] and [PIN+] variants were used to model in vivo interactions between co-existing heterologous amyloid aggregates. Two levels of structural organization, like those previously described for [PSI+], were demonstrated for [PIN+]. In cells with both [PSI+] and [PIN+] the two prions formed separate structures at both levels. Also, the destabilization of [PSI+] by certain [PIN+] variants was shown not to involve alterations in the [PSI+] prion size. Finally, when two variants of the same prion that have aggregates with distinct biochemical characteristics were combined in a single cell, only one aggregate type was propagated. These studies demonstrate the intracellular organization of yeast prions and provide insight into the principles of in vivo amyloid assembly.
Bagriantsev
Sviatoslav
S
Laboratory for Molecular Biology, University of Illinois, Chicago, Illinois 60607, USA.
Liebman
Susan W
SW
D000682:Amyloid / Q000737:chemistry; D003902:Detergents / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D005808:Genes, Recessive; D019791:Guanidine / Q000737:chemistry; D010454:Peptide Termination Factors; D011328:Prions / Q000737:chemistry*; D011487:Protein Conformation; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D013696:Temperature
D000682:Amyloid; D003902:Detergents; D010454:Peptide Termination Factors; D011328:Prions; C404807:RNQ1 protein, S cerevisiae; C068068:SUP35 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D012967:Sodium Dodecyl Sulfate; D019791:Guanidine