Macromolecular organization of ATP synthase and complex I in whole mitochondria.
Proc Natl Acad Sci U S A
; 108(34): 14121-6, 2011 Aug 23.
Article
em En
| MEDLINE
| ID: mdl-21836051
ABSTRACT
We used electron cryotomography to study the molecular arrangement of large respiratory chain complexes in mitochondria from bovine heart, potato, and three types of fungi. Long rows of ATP synthase dimers were observed in intact mitochondria and cristae membrane fragments of all species that were examined. The dimer rows were found exclusively on tightly curved cristae edges. The distance between dimers along the rows varied, but within the dimer the distance between F(1) heads was constant. The angle between monomers in the dimer was 70° or above. Complex I appeared as L-shaped densities in tomograms of reconstituted proteoliposomes. Similar densities were observed in flat membrane regions of mitochondrial membranes from all species except Saccharomyces cerevisiae and identified as complex I by quantum-dot labeling. The arrangement of respiratory chain proton pumps on flat cristae membranes and ATP synthase dimer rows along cristae edges was conserved in all species investigated. We propose that the supramolecular organization of respiratory chain complexes as proton sources and ATP synthase rows as proton sinks in the mitochondrial cristae ensures optimal conditions for efficient ATP synthesis.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
ATPases Mitocondriais Próton-Translocadoras
/
Complexo I de Transporte de Elétrons
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Substâncias Macromoleculares
/
Mitocôndrias
Limite:
Animals
Idioma:
En
Ano de publicação:
2011
Tipo de documento:
Article