ALS-linked mutant superoxide dismutase 1 (SOD1) alters mitochondrial protein composition and decreases protein import.

Autor: Li Q; Department of Neurology, Hope Center for Neurological Disorders, The Washington University School of Medicine, St Louis, MO 63110, USA., Vande Velde C, Israelson A, Xie J, Bailey AO, Dong MQ, Chun SJ, Roy T, Winer L, Yates JR, Capaldi RA, Cleveland DW, Miller TM
Jazyk: angličtina
Zdroj: Proceedings of the National Academy of Sciences of the United States of America [Proc Natl Acad Sci U S A] 2010 Dec 07; Vol. 107 (49), pp. 21146-51. Date of Electronic Publication: 2010 Nov 15.
DOI: 10.1073/pnas.1014862107
Abstrakt: Mutations in superoxide dismutase 1 (SOD1) cause familial ALS. Mutant SOD1 preferentially associates with the cytoplasmic face of mitochondria from spinal cords of rats and mice expressing SOD1 mutations. Two-dimensional gels and multidimensional liquid chromatography, in combination with tandem mass spectrometry, revealed 33 proteins that were increased and 21 proteins that were decreased in SOD1(G93A) rat spinal cord mitochondria compared with SOD1(WT) spinal cord mitochondria. Analysis of this group of proteins revealed a higher-than-expected proportion involved in complex I and protein import pathways. Direct import assays revealed a 30% decrease in protein import only in spinal cord mitochondria, despite an increase in the mitochondrial import components TOM20, TOM22, and TOM40. Recombinant SOD1(G93A) or SOD1(G85R), but not SOD1(WT) or a Parkinson's disease-causing, misfolded α-synuclein(E46K) mutant, decreased protein import by >50% in nontransgenic mitochondria from spinal cord, but not from liver. Thus, altered mitochondrial protein content accompanied by selective decreases in protein import into spinal cord mitochondria comprises part of the mitochondrial damage arising from mutant SOD1.
Databáze: MEDLINE