In vitro analysis of SpUre2p, a prion-related protein, exemplifies the relationship between amyloid and prion.
The yeast Saccharomyces cerevisiae contains in its proteome at least three prion proteins. These proteins (Ure2p, Sup35p, and Rnq1p) share a set of remarkable properties. In vivo, they form aggregates that self-perpetuate their aggregation. This aggregation is controlled by Hsp104, which plays a major role in the growth and severing of these prions. In vitro, these prion proteins form amyloid fibrils spontaneously. The introduction of such fibrils made from Ure2p or Sup35p into yeast cells leads to the prion phenotypes [URE3] and [PSI], respectively. Previous studies on evolutionary biology of yeast prions have clearly established that [URE3] is not well conserved in the hemiascomycetous yeasts and particularly in S. paradoxus. Here we demonstrated that the S. paradoxus Ure2p is able to form infectious amyloid. These fibrils are more resistant than S. cerevisiae Ure2p fibrils to shear force. The observation, in vivo, of a distinct aggregation pattern for GFP fusions confirms the higher propensity of SpUre2p to form fibrillar structures. Our in vitro and in vivo analysis of aggregation propensity of the S. paradoxus Ure2p provides an explanation for its loss of infective properties and suggests that this protein belongs to the non-prion amyloid world.
Immel
Francoise
F
IBGC, UMR5095 CNRS-Université Bordeaux2, 1, rue Camille Saint Saens, 33077 Bordeaux cedex, France.
Jiang
Yi
Y
Wang
Yi-Qian
YQ
Marchal
Christelle
C
Maillet
Laurent
L
Perrett
Sarah
S
Cullin
Christophe
C
D000682:Amyloid / Q000737:chemistry*; D002845:Chromatography; D005979:Glutathione Peroxidase; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000378:metabolism*; D007700:Kinetics; D016366:Open Reading Frames; D010454:Peptide Termination Factors; D010641:Phenotype; D011328:Prions / Q000737:chemistry* / Q000378:metabolism*; D011506:Proteins / Q000737:chemistry; D011994:Recombinant Proteins / Q000737:chemistry; D012440:Saccharomyces / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000378:metabolism*; D013045:Species Specificity
D000682:Amyloid; D006360:Heat-Shock Proteins; D010454:Peptide Termination Factors; D011328:Prions; D011506:Proteins; D011994:Recombinant Proteins; C068068:SUP35 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; C070972:HsP104 protein, S cerevisiae; D049452:Green Fluorescent Proteins; D005979:Glutathione Peroxidase; C067020:URE2 protein, S cerevisiae