Pathways of allosteric regulation in Hsp70 chaperones (original) (raw)

“…GrpE enhances the release of ADP by DnaK so that ATP can bind to restart the cycle. DnaK exhibits an "open" conformation when bound to ATP and shows high on/off rates for substrate, whereas it exhibits slow on/off rates and a closed conformation when bound to ADP (27)(28)(29)(30).…”

Section: Significancementioning

“…In order to participate in a series of physiological functions, a (large) HSP has to be detached from its client peptides (proteins). HSP70 and other chaperones utilize an ATPase domain to hydrolyze ATP and then take on a free conformation [163]. The small HSP27 does not have such an ATPase domain, and HSP70 can react to take away the clients from HSP27; therefore, HSP70 appears to play role in "activating" the smaller HSPs.…”

Section: Overexpression Of Constitutive Hsps Is Not the Cause But Thmentioning

“…The first type includes Hsp27, Hsp70 and Hsp90, and they interact directly with the surfaces of unfolded proteins[4–6] (Box1). By contrast, the second type (which includes the chaperonin Hsp60) assembles into complexes resembling folding chambers, which form privileged environments that exclude bulk cytoplasm and favor recovery of active protein conformations[7].…”

Section: Introduction To Hsps Chaperones and Cancermentioning