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Stress-induced OMA1 activation and autocatalytic turnover regulate OPA1-dependent mitochondrial dynamics.
- Source :
-
The EMBO journal [EMBO J] 2014 Mar 18; Vol. 33 (6), pp. 578-93. Date of Electronic Publication: 2014 Feb 18. - Publication Year :
- 2014
-
Abstract
- The dynamic network of mitochondria fragments under stress allowing the segregation of damaged mitochondria and, in case of persistent damage, their selective removal by mitophagy. Mitochondrial fragmentation upon depolarisation of mitochondria is brought about by the degradation of central components of the mitochondrial fusion machinery. The OMA1 peptidase mediates the degradation of long isoforms of the dynamin-like GTPase OPA1 in the inner membrane. Here, we demonstrate that OMA1-mediated degradation of OPA1 is a general cellular stress response. OMA1 is constitutively active but displays strongly enhanced activity in response to various stress insults. We identify an amino terminal stress-sensor domain of OMA1, which is only present in homologues of higher eukaryotes and which modulates OMA1 proteolysis and activation. OMA1 activation is associated with its autocatalyic degradation, which initiates from both termini of OMA1 and results in complete OMA1 turnover. Autocatalytic proteolysis of OMA1 ensures the reversibility of the response and allows OPA1-mediated mitochondrial fusion to resume upon alleviation of stress. This differentiated stress response maintains the functional integrity of mitochondria and contributes to cell survival.
- Subjects :
- Animals
Centrifugation, Density Gradient
Electrophoresis, Polyacrylamide Gel
Fibroblasts
Immunoblotting
Metalloproteases genetics
Mice
Mice, Knockout
Microscopy, Fluorescence
Mitochondrial Proteins genetics
Enzyme Activation physiology
GTP Phosphohydrolases metabolism
Metalloproteases metabolism
Mitochondrial Dynamics physiology
Mitochondrial Proteins metabolism
Models, Biological
Stress, Physiological physiology
Subjects
Details
- Language :
- English
- ISSN :
- 1460-2075
- Volume :
- 33
- Issue :
- 6
- Database :
- MEDLINE
- Journal :
- The EMBO journal
- Publication Type :
- Academic Journal
- Accession number :
- 24550258
- Full Text :
- https://doi.org/10.1002/embj.201386474