Functional diversification of hsp40: distinct j-protein functional requirements for two prions allow for chaperone-dependent prion selection.

ABSTRACT: Yeast prions are heritable amyloid aggregates of functional yeast proteins; their propagation to subsequent cell generations is dependent upon fragmentation of prion protein aggregates by molecular chaperone proteins. Mounting evidence indicates the J-protein Sis1 may act as an amyloid specificity factor, recognizing prion and other amyloid aggregates and enabling Ssa and Hsp104 to act in prion fragmentation. Chaperone interactions with prions, however, can be affected by variations in amyloid-core structure resulting in distinct prion variants or 'strains'. Our genetic analysis revealed that Sis1 domain requirements by distinct variants of [PSI+] are strongly dependent upon overall variant stability. Notably, multiple strong [PSI+] variants can be maintained by a minimal construct of Sis1

SUBMITTER: Harris JM 

PROVIDER: S-EPMC4109904 | biostudies-literature | 2014 Jul

REPOSITORIES: biostudies-literature