Molecular Mechanism of J-Domain-Triggered ATP Hydrolysis by Hsp70 Chaperones

Mol Cell. 2018 Jan 18;69(2):227-237.e4. doi: 10.1016/j.molcel.2017.12.003. Epub 2017 Dec 28.


Efficient targeting of Hsp70 chaperones to substrate proteins depends on J-domain cochaperones, which in synergism with substrates trigger ATP hydrolysis in Hsp70s and concomitant substrate trapping. We present the crystal structure of the J-domain of Escherichia coli DnaJ in complex with the E. coli Hsp70 DnaK. The J-domain interacts not only with DnaK's nucleotide-binding domain (NBD) but also with its substrate-binding domain (SBD) and packs against the highly conserved interdomain linker. Mutational replacement of contacts between J-domain and SBD strongly reduces the ability of substrates to stimulate ATP hydrolysis in the presence of DnaJ and compromises viability at heat shock temperatures. Our data demonstrate that the J-domain and the substrate do not deliver completely independent signals for ATP hydrolysis, but the J-domain, in addition to its direct influence on Hsp70s catalytic center, makes Hsp70 more responsive for the hydrolysis-inducing signal of the substrate, resulting in efficient substrate trapping.

Keywords: Hsp40; Hsp70; allostery; interdomain communication; molecular chaperones; protein folding.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphatases / metabolism
  • Adenosine Triphosphate / metabolism
  • Binding Sites
  • Escherichia coli / metabolism
  • Escherichia coli Proteins / metabolism*
  • Escherichia coli Proteins / ultrastructure*
  • HSP40 Heat-Shock Proteins / metabolism*
  • HSP40 Heat-Shock Proteins / ultrastructure*
  • HSP70 Heat-Shock Proteins / metabolism*
  • HSP70 Heat-Shock Proteins / physiology
  • HSP70 Heat-Shock Proteins / ultrastructure
  • Heat-Shock Proteins / metabolism
  • Hydrolysis
  • Kinetics
  • Models, Molecular
  • Molecular Chaperones / metabolism
  • Protein Domains / physiology


  • DnaJ protein, E coli
  • Escherichia coli Proteins
  • HSP40 Heat-Shock Proteins
  • HSP70 Heat-Shock Proteins
  • Heat-Shock Proteins
  • Molecular Chaperones
  • Adenosine Triphosphate
  • Adenosine Triphosphatases
  • dnaK protein, E coli