SGT, a Hsp90beta binding partner, is accumulated in the nucleus during cell apoptosis

Biochem Biophys Res Commun. 2006 May 19;343(4):1153-8. doi: 10.1016/j.bbrc.2006.03.090. Epub 2006 Mar 24.

Abstract

In this study, we reported that small glutamine-rich TPR-containing protein (SGT) interacted with not only Hsp90alpha but also Hsp90beta. Confocal analysis showed that treatment of cells with Hsp90-specific inhibitor geldanamycin (GA) disrupted the interaction of SGT with Hsp90beta and this contributed to the increase of nuclear localization of SGT in HeLa cells. The increased nuclear localization of SGT was further confirmed by the Western blotting in GA-treated HeLa cells and H1299 cells. In our previous study, SGT was found to be a new pro-apoptotic factor, so we wondered whether the sub-cellular localization of SGT was related with cell apoptosis. By confocal analysis we found that the nuclear import of SGT was significantly increased in STS-induced apoptotic HeLa cells, which implied that the sub-cellular localization of SGT was closely associated with Hsp90beta and apoptosis.

MeSH terms

  • Active Transport, Cell Nucleus
  • Apoptosis*
  • Carrier Proteins / biosynthesis
  • Carrier Proteins / metabolism*
  • Cell Line
  • Cell Nucleus / metabolism*
  • Cytoplasm / metabolism
  • HSP90 Heat-Shock Proteins / antagonists & inhibitors
  • HSP90 Heat-Shock Proteins / metabolism*
  • Humans
  • Molecular Chaperones
  • Protein Binding

Substances

  • Carrier Proteins
  • HSP90 Heat-Shock Proteins
  • HSP90AB1 protein, human
  • Molecular Chaperones
  • SGTA protein, human