Hsp70 chaperones accelerate protein translocation and the unfolding of stable protein aggregates by entropic pulling.

ABSTRACT: Hsp70s are highly conserved ATPase molecular chaperones mediating the correct folding of de novo synthesized proteins, the translocation of proteins across membranes, the disassembly of some native protein oligomers, and the active unfolding and disassembly of stress-induced protein aggregates. Here, we bring thermodynamic arguments and biochemical evidences for a unifying mechanism named entropic pulling, based on entropy loss due to excluded-volume effects, by which Hsp70 molecules can convert the energy of ATP hydrolysis into a force capable of accelerating the local unfolding of various protein substrates and, thus, perform disparate cellular functions. By means of entropic pulling, individual Hsp70 molecules can accelerate unfolding and pulling of translocating polypeptides into mitoc

SUBMITTER: De Los Rios P 

PROVIDER: S-EPMC1458849 | biostudies-literature | 2006 Apr

REPOSITORIES: biostudies-literature