Affordable Access

Hsp27 protects mitochondria of thermotolerant cells against apoptotic stimuli.

Authors
  • Samali, A
  • Robertson, J D
  • Peterson, E
  • Manero, F
  • van Zeijl, L
  • Paul, C
  • Cotgreave, I A
  • Arrigo, A P
  • Orrenius, S
Type
Published Article
Journal
Cell stress & chaperones
Publication Date
Jan 01, 2001
Volume
6
Issue
1
Pages
49–58
Identifiers
PMID: 11525243
Source
Medline
License
Unknown

Abstract

Enhanced cell survival and resistance to apoptosis during thermotolerance correlates with an increased expression of heat shock proteins (Hsps). Here we present additional evidence in support of the hypothesis that the induction of Hsp27 and Hsp72 during acquired thermotolerance in Jurkat T-lymphocytes prevents apoptosis. In thermotolerant cells, Hsp27 was shown to associate with the mitochondrial fraction, and inhibition of Hsp27 induction during thermotolerance in cells transfected with hsp27 antisense potentiated mitochondrial cytochrome c release after exposure to various apoptotic stimuli, despite the presence of elevated levels of Hsp72. Caspase activation and apoptosis were inhibited under these conditions. In vitro studies revealed that recombinant Hsp72 more efficiently blocked cytochrome c-mediated caspase activation than did recombinant Hsp27. A model is presented for the inhibition of apoptosis during thermotolerance in which Hsp27 preferentially blocks mitochondrial cytochrome c release, whereas Hsp72 interferes with apoptosomal caspase activation.

Report this publication

Statistics

Seen <100 times