skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Polyglutamine expansion inhibits respiration by increasing reactive oxygen species in isolated mitochondria

Journal Article · · Biochemical and Biophysical Research Communications
 [1];  [1];  [1];  [1]
  1. Deane Laboratory, Department of Medicine, Division of Neurology, Duke University Medical Center, Durham, NC 27710 (United States)

Huntington's disease results from expansion of the polyglutamine (PolyQ) domain in the huntingtin protein. Although the cellular mechanism by which pathologic-length PolyQ protein causes neurodegeneration is unclear, mitochondria appear central in pathogenesis. We demonstrate in isolated mitochondria that pathologic-length PolyQ protein directly inhibits ADP-dependent (state 3) mitochondrial respiration. Inhibition of mitochondrial respiration by PolyQ protein is not due to reduction in the activities of electron transport chain complexes, mitochondrial ATP synthase, or the adenine nucleotide translocase. We show that pathologic-length PolyQ protein increases the production of reactive oxygen species in isolated mitochondria. Impairment of state 3 mitochondrial respiration by PolyQ protein is reversed by addition of the antioxidants N-acetyl-L-cysteine or cytochrome c. We propose a model in which pathologic-length PolyQ protein directly inhibits mitochondrial function by inducing oxidative stress.

OSTI ID:
20798838
Journal Information:
Biochemical and Biophysical Research Communications, Vol. 341, Issue 2; Other Information: DOI: 10.1016/j.bbrc.2006.01.007; PII: S0006-291X(06)00064-7; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0006-291X
Country of Publication:
United States
Language:
English