Molecular architecture of the active mitochondrial protein gate.
Science
; 349(6255): 1544-8, 2015 Sep 25.
Article
em En
| MEDLINE
| ID: mdl-26404837
ABSTRACT
Mitochondria fulfill central functions in cellular energetics, metabolism, and signaling. The outer membrane translocator complex (the TOM complex) imports most mitochondrial proteins, but its architecture is unknown. Using a cross-linking approach, we mapped the active translocator down to single amino acid residues, revealing different transport paths for preproteins through the Tom40 channel. An N-terminal segment of Tom40 passes from the cytosol through the channel to recruit chaperones from the intermembrane space that guide the transfer of hydrophobic preproteins. The translocator contains three Tom40 ß-barrel channels sandwiched between a central α-helical Tom22 receptor cluster and external regulatory Tom proteins. The preprotein-translocating trimeric complex exchanges with a dimeric isoform to assemble new TOM complexes. Dynamic coupling of α-helical receptors, ß-barrel channels, and chaperones generates a versatile machinery that transports about 1000 different proteins.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Saccharomyces cerevisiae
/
Proteínas de Transporte da Membrana Mitocondrial
Idioma:
En
Revista:
Science
Ano de publicação:
2015
Tipo de documento:
Article
País de afiliação:
Japão