title: Uncoupling protein 1 affects the yeast mitoproteome and oxygen free radical production.
abstract: Uncoupling protein 1 (UCP1) is a mitochondrial inner membrane protein that dissipates the proton electrochemical gradient built up by the respiratory chain. Its activity is stimulated by free fatty acids and inhibited by purine nucleotides. Here we investigated how active and regulated recombinant UCP1 expressed in yeast at approximately 1 and approximately 10 microg/mg of total mitochondrial proteins induced changes in the mitochondrial proteome and in oxygen free radical production. Using two-dimensional differential in-gel electrophoresis (2D-DIGE), we found that most of the proteins involved in the response to ectopically expressed UCP1 are related to energy metabolism. We also quantified the cellular H(2)O(2) release in the absence or in the presence of UCP1. Our results suggest that UCP1 has a dual influence on free radical generation. On one side, FFA-activated UCP1 was able to decrease the superoxide anion production, demonstrating that a decrease in the generation of reactive oxygen species is an obligatory outcome of UCP1 activity even in a heterologous context. On the other side, an increase in UCP1 content was concomitant with an increase in the basal release of superoxide anion by mitochondria as a side consequence of the overall increase in oxidative metabolism.
authors.affiliation: Laboratory of Bioenergetics, Bât. B6c, Allée de la chimie 3, 4000 Liège, Belgium.
authors.forename: Pierre
authors.initials: P
authors.lastname: Douette
authors.forename: Pascal
authors.initials: P
authors.lastname: Gerkens
authors.forename: Rachel
authors.initials: R
authors.lastname: Navet
authors.forename: Pierre
authors.initials: P
authors.lastname: Leprince
authors.forename: Edwin
authors.initials: E
authors.lastname: De Pauw
authors.forename: Francis E
authors.initials: FE
authors.lastname: Sluse
mesh_terms: D000818:Animals; D015153:Blotting, Western; D002352:Carrier Proteins / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods; D005609:Free Radicals / Q000378:metabolism; D005786:Gene Expression Regulation; D018014:Gene Transfer Techniques; D007473:Ion Channels; D008565:Membrane Proteins / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D024101:Mitochondrial Proteins / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D010641:Phenotype; D040901:Proteomics / Q000379:methods; D051381:Rats; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D000071256:Uncoupling Protein 1
chemical_list: D002352:Carrier Proteins; D005609:Free Radicals; D007473:Ion Channels; D008565:Membrane Proteins; D024101:Mitochondrial Proteins; D011994:Recombinant Proteins; C000604373:Ucp1 protein, rat; D000071256:Uncoupling Protein 1; D010100:Oxygen