Importance of low-oligomeric-weight species for prion propagation in the yeast prion system Sup35/Hsp104.

ABSTRACT: The [PSI+] determinant of Saccharomyces cerevisiae, consisting of the cytosolic translation termination factor Sup35, is a prion-type genetic element that induces an inheritable conformational change and converts the Sup35 protein into amyloid fibers. The molecular chaperone Hsp104 is required to maintain self-replication of [PSI+]. We observe in vitro that addition of catalytic amounts of Hsp104 to the prion-determining region of the NM domain of Sup35, Sup355-26, results in the dissociation of oligomeric Sup35 into monomeric species. Several intermediates of Sup355-26 could be detected during this process. Strong interactions are found between Hsp104 and hexameric/tetrameric Sup355-26, whereas the intermediate and monomeric "release" forms show a decreased affinity with respect to Hsp104

SUBMITTER: Narayanan S 

PROVIDER: S-EPMC170910 | biostudies-literature | 2003 Aug

REPOSITORIES: biostudies-literature