Version française
From left to right, upper row:
Lucile Moynie, Marie-France Giraud, Alain Dautant, Daniel Brèthes.
From left to right, bottom row:
Patrick Paumard, Jean-Claude Talbot, Jean Velours, Théodore Weimann, Jacques Vailler, Vanessa Goyon, Pierre-Vincent Graves.
Ph.: 00 33 5 56 99 90 01
Fax: 00 33 5 56 99 90 51
The F1-Fo ATP-synthase is the smallest rotary molecular motor of the living world. This enzymatic complex utilizes the electrochemical gradient, generated by redox chains to synthesize adenosine triphosphate (ATP). We study the mitochondrial enzyme of the yeast Saccharomyces cerevisiae. This micro-organism has been chosen because it is a good model of eukaryotic cells and its growth on non-fermentescible carbon sources (conditions in which ATP synthesis only relies on ATP-synthase) is quick and easy. Furthermore, molecular biology techniques are straightforward in this organism. We employ biochemical methods (purification, sequence analyses, cross-linking, enzymology), molecularbiology (cloning, DNA sequencing, site-directed mutagenesis, over-expression) and biophysical techniques (circular dichroism, NMR, X-ray crystallography) to elucidate the structure of this complex or of some parts of this enzyme. We are also interested in the enzyme mechanism, its regulation and its involvement in mitochondrial morphogenesis.
Cryo-electron micrographs of wild type strain (WT), strains devoid of subunit i (DATP18), of subunit g (Dg) or of subunit e (De). WT and DATP18 cells display normal mitochondria (m, round shape, well-developped cristae network) whereas in strains Dg and De, mitochondria (ma) have an altered morphology with large onion-like structures. Bars = 0.5 µm.
In collaboration with the "Structure et Fonction des Nucléoside diphosphate kinases" team.
Lab Director: Ioan Lascu.
"Nucléoside diphosphate kinase" of Escherichia coli structure
Electrophoresis (BN-PAGE, SDS-PAGE), Western Blot, recombinant protein production, site-directed mutagenesis, protein purification, peptide sequencing, amino acid composition, crystallization, three-dimensional structure determination, X-ray crystallography, oxigraphy, electron microscopy, chemical cross-linking, mass spectrometry...
HPLC, FPLC, oxigraph, spectrofluorimeters, spectrophotometers, ultra-centrifuges, fermentors, electrophoresis systems
Fronzes, R., Weimann, T., Vaillier, J., Velours, J. and Brèthes, D. (2006) The peripheral stalk participates in the yeast ATP synthase dimerization independently of e and g subunits. Biochemistry 45, 6715-6723.
Bustos DM, and Velours J. (2005) The modification of the conserved GXXXG motif of the membrane-spanning segment of subunit g destabilizes the supramolecular species of yeast ATP synthase. J Biol Chem 280, 29004-29010.
Lefebvre-Legendre L, Salin B, Schaeffer J, Brethes D, Dautant A, Ackerman SH, and di Rago JP. (2005) Failure to assemble the alpha 3 beta 3 subcomplex of the ATP synthase leads to accumulation of the α and β subunits within inclusion bodies and the loss of mitochondrial cristae in Saccharomyces cerevisiae. J Biol Chem 280, 18386-18392.
Arselin G, Vaillier J, Salin B, Schaeffer J, Giraud MF, Dautant A, Brethes D, and Velours J. (2004) The modulation in subunits e and g amounts of yeast ATP synthase modifies mitochondrial cristae morphology. J Biol Chem 279, 40392-40399.
Galkin M, Venard R, Vaillier J, Velours J, and Haraux F. (2004) Functional transitions of F0F1-ATPase mediated by the inhibitory peptide IF1 in yeast coupled sub-mitochondrial particles. Eur J Biochem 271, 1963-1970.
Fronzes R, Chaignepain S, Bathany K, Giraud MF, Arselin G, Schmitter JM, Dautant A, Velours J, and Brethes D. (2003) Topological and functional study of subunit h of the F1Fo ATP synthase complex in yeast Saccharomyces cerevisiae. Biochemistry 42, 12038-12049.
Venard R, Brethes D, Giraud MF, Vaillier J, Velours J, and Haraux F. (2003) Investigation of the role and mechanism of IF1 and STF1 proteins, twin inhibitory peptides which interact with the yeast mitochondrial ATP synthase. Biochemistry 42, 7626-7636.
Duvezin-Caubet S, Caron M, Giraud MF, Velours J, and di Rago JP. (2003) The two rotor components of yeast mitochondrial ATP synthase are mechanically coupled by subunit delta. Proc Natl Acad Sci U S A 100, 13235-13240.
Nazabal A, Laguerre M, Schmitter JM, Vaillier J, Chaignepain S, and Velours J. (2003) Hydrogen / deuterium exchange on yeast ATPase supramolecular protein complex analyzed at high sensitivity by MALDI mass spectrometry. J Am Soc Mass Spectrom 14, 471-481.
Arselin G, Giraud MF, Dautant A, Vaillier J, Brethes D, Coulary-Salin B, Schaeffer J, and Velours J. (2003) The GxxxG motif of the transmembrane domain of subunit e is involved in the dimerization/oligomerization of the yeast ATP synthase complex in the mitochondrial membrane. Eur J Biochem 270, 1875-1884.
