Ydj1 but not Sis1 stabilizes Hsp70 protein under prolonged stress in vitro

Biopolymers. 2008 Mar;89(3):171-4. doi: 10.1002/bip.20881.


Yeast cytosol has two important co-chaperons; Ydj1 and Sis1. Genetic experiments showed that Ydj1 is not essential for viability; however, cells lacking it grow very poorly at 30 degrees C or unable to grow at extreme temperatures. On the other hand, Sis1 is an essential protein and apparently plays a functional role at assembly or disassembly of protein complexes. Stability experiments revealed that only Ydj1-protected Hsp70 proteins can hydrolyze ATP under prolonged stress.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adenosine Triphosphatases / metabolism
  • Cytosol / metabolism
  • Enzyme Stability
  • HSP40 Heat-Shock Proteins / metabolism*
  • HSP70 Heat-Shock Proteins / metabolism*
  • Heat-Shock Proteins / metabolism*
  • Luciferases / metabolism
  • Oxidative Stress
  • Protein Binding
  • Protein Folding
  • Saccharomyces cerevisiae Proteins / metabolism*
  • Temperature


  • HSP40 Heat-Shock Proteins
  • HSP70 Heat-Shock Proteins
  • Heat-Shock Proteins
  • SIS1 protein, S cerevisiae
  • Saccharomyces cerevisiae Proteins
  • YDJ1 protein, S cerevisiae
  • Luciferases
  • Adenosine Triphosphatases