A novel mechanism for small heat shock proteins to function as molecular chaperones

Sci Rep. 2015 Mar 6:5:8811. doi: 10.1038/srep08811.


Small heat shock proteins (sHSPs) are molecular chaperones ubiquitously present in all forms of life, but their function mechanisms remain controversial. Here we show by cryo-electron microscopy and single particle 3D reconstruction that, at the low temperatures (4-25°C), CeHSP17 (a sHSP from Caenorhabditis elegans) exists as a 24-subunit spherical oligomer with tetrahedral symmetry. Our studies demonstrate that CeHSP17 forms large sheet-like super-molecular assemblies (SMAs) at the high temperatures (45-60°C), and such SMAs are apparently the form that exhibits chaperone-like activity. Our findings suggest a novel molecular mechanism for sHSPs to function as molecular chaperones.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptation, Biological
  • Animals
  • Caenorhabditis elegans
  • Escherichia coli / genetics
  • Escherichia coli / metabolism
  • Gene Expression
  • Heat-Shock Proteins, Small / chemistry*
  • Heat-Shock Proteins, Small / genetics
  • Heat-Shock Proteins, Small / metabolism
  • Models, Molecular
  • Molecular Chaperones / genetics*
  • Molecular Chaperones / metabolism
  • Protein Aggregates
  • Protein Binding
  • Protein Conformation
  • Recombinant Proteins
  • Temperature


  • Heat-Shock Proteins, Small
  • Molecular Chaperones
  • Protein Aggregates
  • Recombinant Proteins