Evidence for a novel set of small heat-shock proteins that associates with the mitochondria of murine PC12 cells and protects NADH:ubiquinone oxidoreductase from heat and oxidative stress

Arch Biochem Biophys. 1999 May 15;365(2):344-50. doi: 10.1006/abbi.1999.1177.


Several previously unreported small heat-shock proteins (sHsps) were detected in mitochondria from heat-stressed rat PC12 cells, but not in unstressed controls. Functional inactivation of the mitochondrial sHsps with murine Hsp25 antibody indicated that these sHsps protect NADH:ubiquinone oxidoreductase and NADH dehydrogenase activity (i.e., complex I) in submitochondrial vesicles during heat and oxidative stress. These results (i) confirm the existence of multiple sHsps in mammals and indicate that several of these sHsps associate with the mitochondria, (ii) indicate a conserved function between plant and mammalian mitochondrial sHsps in protecting electron transport during stress, and (iii) suggest that these sHsps may play an important role in diseases whose etiology is based upon oxidative damage of complex I.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Antibodies / pharmacology
  • Electron Transport Complex I
  • HSP27 Heat-Shock Proteins
  • Heat-Shock Proteins / metabolism*
  • Hot Temperature
  • Kinetics
  • Mitochondria / metabolism*
  • NADH Dehydrogenase / metabolism
  • NADH, NADPH Oxidoreductases / chemistry*
  • NADH, NADPH Oxidoreductases / metabolism*
  • Neoplasm Proteins / antagonists & inhibitors
  • Neoplasm Proteins / immunology
  • Neoplasm Proteins / metabolism*
  • Oxidative Stress*
  • PC12 Cells
  • Rats
  • Submitochondrial Particles / enzymology


  • Antibodies
  • HSP27 Heat-Shock Proteins
  • Heat-Shock Proteins
  • Hspb1 protein, rat
  • Neoplasm Proteins
  • NADH, NADPH Oxidoreductases
  • NADH Dehydrogenase
  • Electron Transport Complex I