Reference: Duvezin-Caubet S, et al. (2006) A "petite obligate" mutant of Saccharomyces cerevisiae: functional mtDNA is lethal in cells lacking the delta subunit of mitochondrial F1-ATPase. J Biol Chem 281(24):16305-13

Reference Help

Abstract

Within the mitochondrial F1Fo-ATP synthase, the nuclear-encoded delta F1 subunit plays a critical role in coupling the enzyme proton translocating and ATP synthesis activities. In Saccharomyces cerevisiae, deletion of the delta subunit gene (Deltadelta) was shown to result in a massive destabilization of the mitochondrial genome (mtDNA) in the form of 100% rho-/rho degrees petites, i.e. cells missing a large portion (>50%) of the mtDNA (rho-) or totally devoid of mtDNA (rho degrees ). Previous work has suggested that the absence of complete mtDNA (rho+) in Deltadelta yeast is a consequence of an uncoupling of the ATP synthase in the form of a passive proton transport through the enzyme, i.e. not coupled to ATP synthesis. However it was unclear why or how this ATP synthase defect destabilized the mtDNA. We investigated this question using a non respiratory gene (ARG8m) inserted into the mtDNA. We first show that retention of functional mtDNA is lethal to Deltadelta yeast. We further show that combined to a nuclear mutation (Deltaatp4) preventing the ATP synthase proton channel assembly, a lack in delta subunit fails to destabilize the mtDNA and rho+ Deltadelta cells become viable. We conclude that Deltadelta yeast cannot survive when it has the ability to synthesize the ATP synthase proton channel. Accordingly, the rho-/rho degrees mutation can be viewed as a rescuing event because this mutation prevents the synthesis of the two mtDNA encoded subunits (Atp6p and Atp9p) forming the core of this channel. This is the first report of what we have called a 'petite-obligate' mutant of S. cerevisiae.

Reference Type
Journal Article
Authors
Duvezin-Caubet S, Rak M, Lefebvre-Legendre L, Tetaud E, Bonnefoy N, di Rago JP
Primary Lit For
Additional Lit For
Review For

Interaction Annotations

Increase the total number of rows showing on this page by using the pull-down located below the table, or use the page scroll at the table's top right to browse through the table's pages; use the arrows to the right of a column header to sort by that column; filter the table using the "Filter" box at the top of the table; click on the small "i" buttons located within a cell for an annotation to view further details about experiment type and any other genes involved in the interaction.

Interactor Interactor Type Assay Annotation Action Modification Phenotype Source Reference

Gene Ontology Annotations

Increase the total number of rows showing on this page using the pull-down located below the table, or use the page scroll at the table's top right to browse through the table's pages; use the arrows to the right of a column header to sort by that column; filter the table using the "Filter" box at the top of the table.

Gene Gene Ontology Term Qualifier Aspect Method Evidence Source Assigned On Annotation Extension Reference

Phenotype Annotations

Increase the total number of rows showing on this page using the pull-down located below the table, or use the page scroll at the table's top right to browse through the table's pages; use the arrows to the right of a column header to sort by that column; filter the table using the "Filter" box at the top of the table; click on the small "i" buttons located within a cell for an annotation to view further details.

Gene Phenotype Experiment Type Mutant Information Strain Background Chemical Details Reference

Regulation Annotations

Increase the total number of rows displayed on this page using the pull-down located below the table, or use the page scroll at the table's top right to browse through the table's pages; use the arrows to the right of a column header to sort by that column; to filter the table by a specific experiment type, type a keyword into the Filter box (for example, “microarray”); download this table as a .txt file using the Download button or click Analyze to further view and analyze the list of target genes using GO Term Finder, GO Slim Mapper, SPELL, or YeastMine.

Regulator Target Experiment Assay Construct Conditions Strain Background Reference