Extended Data Fig. 5: Entropic-pulling model of amyloid disaggregation by HSP70.
From: Molecular dissection of amyloid disaggregation by human HSP70
a, Entropic pulling: HSP70 bound to monomeric α-syn can freely move in all directions. Fibril bound HSP70 in contrast collides with the amyloid surface. The extent to which its movement is restricted depends on how close to the amyloid surface the chaperone is bound. Frequent collision with the amyloid surface generates a momentum away from the amyloid surface, pulling the bound α-syn protomer along. This model of HSP70 chaperone action is termed entropic pulling. Entropic-pulling forces can be amplified by a high overall density of chaperones, which results in collisions not only with the fibril surface but also between chaperones. b, HSP70 oligomerization. Fluorescence intensity of HSP70AF488 after titration with HSP70AF594. Data are mean ± s.e.m. c, Apparent HSP70 dissociation constants for α-syn fibrils in the presence of DNAJB1, derived from the titration data in Fig. 3b by fit of the mean polarization values at each concentration of fibrils to a binding model assuming a 1:1 (black) or 1:2 (orange) HSP70 to α-syn stoichiometry. Reaction conditions and number of replicates are specified in Extended Data Table 2.
