Reconstitution of novel mitochondrial uncoupling proteins UCP2 and UCP3.
Reconstitution of novel mitochondrial uncoupling proteins, human UCP2 and UCP3, expressed in yeast, was performed to characterize fatty acid (FA)-induced H+ efflux in the resulted proteoliposomes. We now demonstrate for the first time that representatives of physiologically abundant long chain FAs, saturated or unsaturated, activate H+ translocation in UCP2- and UCP3-proteoliposomes. Efficiency of lauric, palmitic or linoleic acid was roughly the same, but oleic acid induced faster H+ uniport. We have confirmed that ATP and GTP inhibit such FA-induced H+ uniport mediated by UCP2 and UCP3. Coenzyme Q10 did not further significantly activate the observed H+ efflux. In conclusion, careful instant reconstitution yields intact functional recombinant proteins, UCP2 and UCP3, the activity of which is comparable with UCP1.
Záckova
Markéta
M
Institute of Physiology, Academy of Sciences of the Czech Republic, Prague.
Jezek
Petr
P
D002352:Carrier Proteins / Q000378:metabolism; D005227:Fatty Acids / Q000378:metabolism; D006801:Humans; D007473:Ion Channels; D026901:Membrane Transport Proteins; D008928:Mitochondria / Q000378:metabolism*; D024101:Mitochondrial Proteins; D011506:Proteins / Q000378:metabolism*; D000071246:Uncoupling Protein 2; D000071247:Uncoupling Protein 3; D015003:Yeasts / Q000378:metabolism
D002352:Carrier Proteins; D005227:Fatty Acids; D007473:Ion Channels; D026901:Membrane Transport Proteins; D024101:Mitochondrial Proteins; D011506:Proteins; C000604389:UCP2 protein, human; C000604392:UCP3 protein, human; D000071246:Uncoupling Protein 2; D000071247:Uncoupling Protein 3