Medical College of Wisconsin
CTSICores SearchResearch InformaticsREDCap

Insertion of proteins into the inner membrane of mitochondria: the role of the Oxa1 complex. Biochim Biophys Acta 2002 Sep 02;1592(1):79-87



Pubmed ID





The inner mitochondrial membrane harbors a large number of proteins that display a wide range of topological arrangements. The majority of these proteins are encoded in the cell's nucleus, but a few polytopic proteins, all subunits of respiratory chain complexes are encoded by the mitochondrial genome. A number of distinct sorting mechanisms exist to direct these proteins into the mitochondrial inner membrane. One of these pathways involves the export of proteins from the matrix into the inner membrane and is used by both proteins synthesized within the mitochondria, as well as by a subset of nuclear encoded proteins. Prior to embarking on the export pathway, nuclear encoded proteins using this sorting route are initially imported into the mitochondrial matrix from the cytosol, their site of synthesis. Protein export from the matrix into the inner membrane bears similarities to Sec-independent protein export in bacteria and requires the function of the Oxa1 protein. Oxa1 is a component of a general protein insertion site in yeast mitochondrial inner membrane used by both nuclear and mitochondrial DNA encoded proteins. Oxa1 is a member of the conserved Oxa1/YidC/Alb3 protein family found throughout prokaryotes throughout eukaryotes (where it is found in mitochondria and chloroplasts). The evidence to demonstrate that the Oxa1/YidC/Alb3 protein family represents a novel evolutionarily conserved membrane insertion machinery is reviewed here.

Author List

Stuart R


Rosemary Stuart PhD Professor in the Biology department at Marquette University

MESH terms used to index this publication - Major topics in bold

Binding Sites
DNA, Mitochondrial
Electron Transport Complex IV
Evolution, Molecular
Intracellular Membranes
Membrane Proteins
Mitochondrial Proteins
Nuclear Proteins
Protein Transport
Saccharomyces cerevisiae
jenkins-FCD Prod-482 91ad8a360b6da540234915ea01ff80e38bfdb40a