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Title: The mtDNA NARP mutation activates the actin-Nrf2 signaling of antioxidant defenses

Abstract

An efficient handling of superoxides by antioxidant defenses is a crucial issue for cells with respiratory chain deficient mitochondria. We used human cultured skin fibroblasts to delineate the mechanism controlling the expression of antioxidant defenses in the case of a severe ATPase deficiency resulting from an 8993T>G mutation in the mitochondrial ATPase6 gene. We observed the nuclear translocation of the transcription factor Nrf2 associated with thinning of the actin stress fibers. The mobilization of the Nrf2 signaling pathway could be mimicked by a chemical blockade of the ATPase with a specific inhibitor, oligomycin. Interestingly enough, Nrf2 nuclear translocation was not observed in the case of a severe cytochrome oxidase deficiency, indicating that studying the status of this signaling pathway could throw some light on the importance of the oxidative insult associated with different respiratory chain defects.

Authors:
; ;  [1];  [2];  [1];  [3]
  1. Inserm, U676, Hopital Robert Debre, 48 Boulevard Serurier, Batiment Ecran, Paris F-75019 (France)
  2. (France)
  3. (France), E-mail: rustin@rdebre.inserm.fr
Publication Date:
OSTI Identifier:
21043701
Resource Type:
Journal Article
Resource Relation:
Journal Name: Biochemical and Biophysical Research Communications; Journal Volume: 368; Journal Issue: 3; Other Information: DOI: 10.1016/j.bbrc.2008.01.125; PII: S0006-291X(08)00181-2; Copyright (c) 2008 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
60 APPLIED LIFE SCIENCES; ACTIN; ANTIOXIDANTS; CYTOCHROME OXIDASE; FIBERS; FIBROBLASTS; MITOCHONDRIA; MUTATIONS; OXIDATION; SKIN; TRANSCRIPTION FACTORS; TRANSLOCATION

Citation Formats

Dassa, Emmanuel Philippe, Paupe, Vincent, Goncalves, Sergio, Universite Paris 7, Faculte de medecine Denis Diderot, IFR02 Paris, Rustin, Pierre, and Universite Paris 7, Faculte de medecine Denis Diderot, IFR02 Paris. The mtDNA NARP mutation activates the actin-Nrf2 signaling of antioxidant defenses. United States: N. p., 2008. Web. doi:10.1016/j.bbrc.2008.01.125.
Dassa, Emmanuel Philippe, Paupe, Vincent, Goncalves, Sergio, Universite Paris 7, Faculte de medecine Denis Diderot, IFR02 Paris, Rustin, Pierre, & Universite Paris 7, Faculte de medecine Denis Diderot, IFR02 Paris. The mtDNA NARP mutation activates the actin-Nrf2 signaling of antioxidant defenses. United States. doi:10.1016/j.bbrc.2008.01.125.
Dassa, Emmanuel Philippe, Paupe, Vincent, Goncalves, Sergio, Universite Paris 7, Faculte de medecine Denis Diderot, IFR02 Paris, Rustin, Pierre, and Universite Paris 7, Faculte de medecine Denis Diderot, IFR02 Paris. Fri . "The mtDNA NARP mutation activates the actin-Nrf2 signaling of antioxidant defenses". United States. doi:10.1016/j.bbrc.2008.01.125.
@article{osti_21043701,
title = {The mtDNA NARP mutation activates the actin-Nrf2 signaling of antioxidant defenses},
author = {Dassa, Emmanuel Philippe and Paupe, Vincent and Goncalves, Sergio and Universite Paris 7, Faculte de medecine Denis Diderot, IFR02 Paris and Rustin, Pierre and Universite Paris 7, Faculte de medecine Denis Diderot, IFR02 Paris},
abstractNote = {An efficient handling of superoxides by antioxidant defenses is a crucial issue for cells with respiratory chain deficient mitochondria. We used human cultured skin fibroblasts to delineate the mechanism controlling the expression of antioxidant defenses in the case of a severe ATPase deficiency resulting from an 8993T>G mutation in the mitochondrial ATPase6 gene. We observed the nuclear translocation of the transcription factor Nrf2 associated with thinning of the actin stress fibers. The mobilization of the Nrf2 signaling pathway could be mimicked by a chemical blockade of the ATPase with a specific inhibitor, oligomycin. Interestingly enough, Nrf2 nuclear translocation was not observed in the case of a severe cytochrome oxidase deficiency, indicating that studying the status of this signaling pathway could throw some light on the importance of the oxidative insult associated with different respiratory chain defects.},
doi = {10.1016/j.bbrc.2008.01.125},
journal = {Biochemical and Biophysical Research Communications},
number = 3,
volume = 368,
place = {United States},
year = {Fri Apr 11 00:00:00 EDT 2008},
month = {Fri Apr 11 00:00:00 EDT 2008}
}
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