Analysis of the interaction of small heat shock proteins with unfolding proteins.

  • T S
  • M E
  • M G
 et al. 
  • 2

    Readers

    Mendeley users who have this article in their library.
  • N/A

    Citations

    Citations of this article.

Abstract

The ubiquitous small heat shock proteins (sHsps) are efficient molecular chaperones that interact with nonnative proteins, prevent their aggregation, and support subsequent refolding. No obvious substrate specificity has been detected so far. A striking feature of sHsps is that they form large complexes with nonnative proteins. Here, we used several well established model chaperone substrates, including citrate synthase, alpha-glucosidase, rhodanese, and insulin, and analyzed their interaction with murine Hsp25 and yeast Hsp26 upon thermal unfolding. The two sHsps differ in their modes of activation. In contrast to Hsp25, Hsp26 undergoes a temperature-dependent dissociation that is required for efficient substrate binding. Our analysis shows that Hsp25 and Hsp26 reacted in a similar manner with the nonnative proteins. For all substrates investigated, complexes of defined size and shape were formed. Interestingly, several different nonnative proteins could be incorporated into defined sHsp-substrate complexes. The first substrate protein bound seems to determine the complex morphology. Thus, despite the differences in quaternary structure and mode of activation, the formation of large uniform sHsp-substrate complexes seems to be a general feature of sHsps, and this unique chaperone mechanism is conserved from yeast to mammals.

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document

  • PMID: 12637495

Authors

  • Stromer T

  • Ehrnsperger M

  • Gaestel M

  • Buchner J

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free