title: Assaying the proton transport and regulation of UCP1 using solid supported membranes.
abstract: The uncoupling protein 1 (UCP1) is a mitochondrial protein that carries protons across the inner mitochondrial membrane. It has an important role in non-shivering thermogenesis, and recent evidence suggests its role in human adult metabolism. Using rapid solution exchange on solid supported membranes, we succeeded in measuring electrical currents generated by the transport activity of UCP1. The protein was purified from mouse brown adipose tissue, reconstituted in liposomes and absorbed on solid supported membranes. A fast pH jump activated the ion transport, and electrical signals could be recorded. The currents were characterized by a fast rise and a slow decay, were stable over time, inhibited by purine nucleotides and activated by fatty acids. This new assay permits direct observation of UCP1 activity in controlled cell-free conditions, and opens up new possibilities for UCP1 functional characterization and drug screening because of its robustness and its potential for automation.
authors: Institut de Biologie Structurale, Université Grenoble 1, 38027 Grenoble Cedex 1, France.
authors: Iulia
authors: I
authors: Blesneac
authors: Stéphanie
authors: S
authors: Ravaud
authors: Paul
authors: P
authors: Machillot
authors: Manuela
authors: M
authors: Zoonens
authors: Sandrine
authors: S
authors: Masscheylen
authors: Bruno
authors: B
authors: Miroux
authors: Michel
authors: M
authors: Vivaudou
authors: Eva
authors: E
authors: Pebay-Peyroula
mesh_terms: D000818:Animals; D002474:Cell-Free System; D005227:Fatty Acids / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D007473:Ion Channels / Q000378:metabolism*; D017136:Ion Transport; D008081:Liposomes / Q000378:metabolism*; D008564:Membrane Potentials / Q000187:drug effects; D051379:Mice; D024101:Mitochondrial Proteins / Q000378:metabolism*; D011522:Protons; D011687:Purines / Q000494:pharmacology; D000071256:Uncoupling Protein 1
chemical_list: D005227:Fatty Acids; D007473:Ion Channels; D008081:Liposomes; D024101:Mitochondrial Proteins; D011522:Protons; D011687:Purines; C000604371:UCP1 protein, human; C000604372:Ucp1 protein, mouse; D000071256:Uncoupling Protein 1