Machinery for protein sorting and assembly in the mitochondrial outer membrane

Nils Wiedemann, Vera Kozjak, Agnieszka Chacinska, Birgit Schönfisch, Sabine Rospert, Michael T. Ryan, Nikolaus Pfanner, Chris Meisinger

Research output: Contribution to journalArticleResearchpeer-review

273 Citations (Scopus)

Abstract

Mitochondria contain translocases for the transport of precursor proteins across their outer and inner membranes. It has been assumed that the translocases also mediate the sorting of proteins to their submitochondrial destination. Here we show that the mitochondrial outer membrane contains a separate sorting and assembly machinery (SAM) that operates after the translocase of the outer membrane (TOM). Mas37 forms a constituent of the SAM complex. The central role of the SAM complex in the sorting and assembly pathway of outer membrane proteins explains the various pleiotropic functions that have been ascribed to Mas37 (refs 4, 11-15). These results suggest that the TOM complex, which can transport all kinds of mitochondrial precursor proteins, is not sufficient for the correct integration of outer membrane proteins with a complicated topology, and instead transfers precursor proteins to the SAM complex.

Original languageEnglish
Pages (from-to)565-571
Number of pages7
JournalNature
Volume424
Issue number6948
DOIs
Publication statusPublished - 31 Jul 2003
Externally publishedYes

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