Polyelectrolyte interactions enable rapid association and dissociation in high-affinity disordered protein complexes.

ABSTRACT: Highly charged intrinsically disordered proteins can form complexes with very high affinity in which both binding partners fully retain their disorder and dynamics, exemplified by the positively charged linker histone H1.0 and its chaperone, the negatively charged prothymosin α. Their interaction exhibits another surprising feature: The association/dissociation kinetics switch from slow two-state-like exchange at low protein concentrations to fast exchange at higher, physiologically relevant concentrations. Here we show that this change in mechanism can be explained by the formation of transient ternary complexes favored at high protein concentrations that accelerate the exchange between bound and unbound populations by orders of magnitude. Molecular simulations show how the extreme disord

SUBMITTER: Sottini A 

PROVIDER: S-EPMC7661507 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature