Abstract
Only a few genes remain in the mitochondrial genome retained by every eukaryotic organism that carry out essential functions and are implicated in severe diseases. Experimentally relocating these few genes to the nucleus therefore has both therapeutic and evolutionary implications. Numerous unproductive attempts have been made to do so, with a total of only 5 successes across all organisms. We have taken a novel approach to relocating mitochondrial genes that utilizes naturally nuclear versions from other organisms. We demonstrate this approach on subunit 9/c of ATP synthase, successfully relocating this gene for the first time in any organism by expressing the ATP9 genes from Podospora anserina in Saccharomyces cerevisiae. This study substantiates the role of protein structure in mitochondrial gene transfer: expression of chimeric constructs reveals that the P. anserina proteins can be correctly imported into mitochondria due to reduced hydrophobicity of the first transmembrane segment. Nuclear expression of ATP9, while permitting almost fully functional oxidative phosphorylation, perturbs many cellular properties, including cellular morphology, and activates the heat shock response. Altogether, our study establishes a novel strategy for allotopic expression of mitochondrial genes, demonstrates the complex adaptations required to relocate ATP9, and indicates a reason that this gene was only transferred to the nucleus during the evolution of multicellular organisms.
Publication types
-
Research Support, N.I.H., Extramural
-
Research Support, Non-U.S. Gov't
MeSH terms
-
Biological Evolution
-
Cell Nucleus / enzymology
-
Cell Nucleus / genetics*
-
Fungal Proteins / genetics*
-
Fungal Proteins / metabolism
-
Gene Deletion
-
Genes, Mitochondrial
-
Genome, Mitochondrial
-
Mitochondria / enzymology
-
Mitochondria / genetics*
-
Mitochondrial Proton-Translocating ATPases / genetics*
-
Mitochondrial Proton-Translocating ATPases / metabolism
-
Oxidative Phosphorylation
-
Podospora / enzymology
-
Podospora / genetics*
-
Protein Subunits / genetics
-
Protein Subunits / metabolism
-
Saccharomyces cerevisiae / enzymology
-
Saccharomyces cerevisiae / genetics*
-
Saccharomyces cerevisiae Proteins / genetics*
-
Saccharomyces cerevisiae Proteins / metabolism
-
Transgenes
Substances
-
Fungal Proteins
-
Protein Subunits
-
Saccharomyces cerevisiae Proteins
-
Mitochondrial Proton-Translocating ATPases
-
OLI1 protein, S cerevisiae
Grants and funding
MB was a recipient of a BDI fellowship from the CNRS. AM was supported by the Agence Nationale de la Recherche (ANR). RK was a postdoctoral fellow from the Ministère de la Recherche et des Technologies. This work was supported by grants from the Conseil de la Région Aquitaine and the ANR (to J-PdR), from the CNRS (to AS-C), the CNRS-ATIP Program 2006 and FRM-INE Program 2007 (to SH-LD), and the National Institutes of Health (to LMS). The study was technically supported by the European Molecular Biology Laboratory Genomics Core Facility. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.