Regulation of the inner membrane mitochondrial permeability transition by the outer membrane translocator protein (peripheral benzodiazepine receptor).
J Biol Chem
; 286(2): 1046-53, 2011 Jan 14.
Article
in En
| MEDLINE
| ID: mdl-21062740
ABSTRACT
We studied the properties of the permeability transition pore (PTP) in rat liver mitochondria and in mitoplasts retaining inner membrane ultrastructure and energy-linked functions. Like mitochondria, mitoplasts readily underwent a permeability transition following Ca(2+) uptake in a process that maintained sensitivity to cyclosporin A. On the other hand, major differences between mitochondria and mitoplasts emerged in PTP regulation by ligands of the outer membrane translocator protein of 18 kDa, TSPO, formerly known as the peripheral benzodiazepine receptor. Indeed, (i) in mitoplasts, the PTP could not be activated by photo-oxidation after treatment with dicarboxylic porphyrins endowed with protoporphyrin IX configuration, which bind TSPO in intact mitochondria; and (ii) mitoplasts became resistant to the PTP-inducing effects of N,N-dihexyl-2-(4-fluorophenyl)indole-3-acetamide and of other selective ligands of TSPO. Thus, the permeability transition is an inner membrane event that is regulated by the outer membrane through specific interactions with TSPO.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Porphyrins
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Mitochondria, Liver
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Carrier Proteins
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Calcium
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Receptors, GABA-A
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Mitochondrial Membranes
Limits:
Animals
Language:
En
Journal:
J Biol Chem
Year:
2011
Document type:
Article
Affiliation country: