Format

Send to

Choose Destination
See comment in PubMed Commons below
EMBO J. 2001 Feb 15;20(4):661-71.

A reversible component of mitochondrial respiratory dysfunction in apoptosis can be rescued by exogenous cytochrome c.

Author information

1
Howard Hughes Medical Institute, Department of Pathology, Harvard Medical School, Dana Farber Cancer Institute, Boston, MA 02115, USA.

Abstract

Multiple apoptotic pathways release cytochrome c from the mitochondrial intermembrane space, resulting in the activation of downstream caspases. In vivo activation of Fas (CD95) resulted in increased permeability of the mitochondrial outer membrane and depletion of cytochrome c stores. Serial measurements of oxygen consumption, NADH redox state and membrane potential revealed a loss of respiratory state transitions. This tBID-induced respiratory failure did not require any caspase activity. At early time points, re-addition of exogenous cytochrome c markedly restored respiratory functions. Over time, however, mitochondria showed increasing irreversible respiratory dysfunction as well as diminished calcium buffering. Electron microscopy and tomographic reconstruction revealed asymmetric mitochondria with blebs of herniated matrix, distended inner membrane and partial loss of cristae structure. Thus, apoptogenic redistribution of cytochrome c is responsible for a distinct program of mitochondrial respiratory dysfunction, in addition to the activation of downstream caspases.

PMID:
11179211
PMCID:
PMC145422
DOI:
10.1093/emboj/20.4.661
[Indexed for MEDLINE]
Free PMC Article
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Support Center