Abstract

In Saccharomyces cerevisiae the mature cytochrome bc1 complex exists as an obligate homo-dimer in which each monomer consists of ten distinct protein subunits inserted into or bound to the inner mitochondrial membrane. Among them, the Rieske iron-sulphur protein (Rip1), besides its catalytic role in electron transfer, may be implicated in the bc1 complex dimerization. Indeed, Rip1 has the globular domain containing the catalytic centre in one monomer while the transmembrane helix interacts with the adjacent monomer. In addition, the lack of Rip1 leads to the accumulation of an immature bc1 intermediate, only loosely associated with cytochrome c oxidase. In this study we have investigated the biogenesis of the yeast cytochrome bc1 complex using epitope tagged proteins to purify native assembly intermediates. We showed that the dimerization process is an early event during bc1 complex biogenesis and that the presence of Rip1, differently from previous proposals, is not essential for this process. We also investigated the multi-step model of bc1 assembly thereby lending further support to the existence of bona fide subcomplexes during bc1 maturation in the inner mitochondrial membrane. Finally, a new model of cytochrome bc1 complex assembly, in which distinct intermediates sequentially interact during bc1 maturation, has been proposed.

Autore Pugliese

• Ferramosca Alessandra , Zara Vincenzo

Tutti gli autori

• Conte A. , Papa B. , Ferramosca A. , Zara V.

Titolo volume/Rivista

BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH

Anno di pubblicazione

2015

ISSN

0167-4889

ISBN

Non Disponibile

Numero di citazioni Wos

3

Ultimo Aggiornamento Citazioni

22/04/2018

Numero di citazioni Scopus

5

Ultimo Aggiornamento Citazioni

24/04/2018

Settori ERC

Non Disponibile

Codici ASJC

Non Disponibile