Medical College of Wisconsin
CTSICores SearchResearch InformaticsREDCap

Mapping of the Saccharomyces cerevisiae Oxa1-mitochondrial ribosome interface and identification of MrpL40, a ribosomal protein in close proximity to Oxa1 and critical for oxidative phosphorylation complex assembly. Eukaryot Cell 2009 Nov;8(11):1792-802

Date

09/29/2009

Pubmed ID

19783770

Pubmed Central ID

PMC2772399

DOI

10.1128/EC.00219-09

Abstract

The Oxa1 protein plays a central role in facilitating the cotranslational insertion of the nascent polypeptide chains into the mitochondrial inner membrane. Mitochondrially encoded proteins are synthesized on matrix-localized ribosomes which are tethered to the inner membrane and in physical association with the Oxa1 protein. In the present study we used a chemical cross-linking approach to map the Saccharomyces cerevisiae Oxa1-ribosome interface, and we demonstrate here a close association of Oxa1 and the large ribosomal subunit protein, MrpL40. Evidence to indicate that a close physical and functional relationship exists between MrpL40 and another large ribosomal protein, the Mrp20/L23 protein, is also provided. MrpL40 shares sequence features with the bacterial ribosomal protein L24, which like Mrp20/L23 is known to be located adjacent to the ribosomal polypeptide exit site. We propose therefore that MrpL40 represents the Saccharomyces cerevisiae L24 homolog. MrpL40, like many mitochondrial ribosomal proteins, contains a C-terminal extension region that bears no similarity to the bacterial counterpart. We show that this C-terminal mitochondria-specific region is important for MrpL40's ability to support the synthesis of the correct complement of mitochondrially encoded proteins and their subsequent assembly into oxidative phosphorylation complexes.

Author List

Jia L, Kaur J, Stuart RA

Author

Rosemary Stuart PhD Professor in the Biology department at Marquette University




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

Amino Acid Motifs
Electron Transport Complex IV
Mitochondria
Mitochondrial Proteins
Nuclear Proteins
Oxidation-Reduction
Phosphorylation
Protein Binding
Protein Interaction Mapping
Ribosomal Proteins
Ribosomes
Saccharomyces cerevisiae
Saccharomyces cerevisiae Proteins
jenkins-FCD Prod-482 91ad8a360b6da540234915ea01ff80e38bfdb40a