Fatty acid activation of the reconstituted brown adipose tissue mitochondria uncoupling protein.
The effect of fatty acids, palmitoyl-CoA, and N',N-dicyclohexylcarbodiimide on the ion conductance of the reconstituted brown adipose tissue mitochondria uncoupling protein was investigated. 1, 5, and 10 microM palmitic acid induced a specific, GDP inhibited, increase in proton conductance in proteoliposomes containing the uncoupling protein but not in proteoliposomes prepared with purified protein extracts of liver mitochondria. 10 microM oleic acid, like palmitic acid, increased proton conductance in proteoliposomes prepared with the uncoupling protein. Palmitoyl-CoA and caprylic acid had no effect on increasing proton conductance. Similar to the observation in mitochondria, there was no effect of palmitic acid on Cl-conductance, but unlike mitochondria its activation by palmitoyl-CoA or inhibition by N',N-dicyclohexylcarbodiimide was lost. The results, obtained in an isolated system, provide support for the contention that long chain fatty acids act as an acute physiological activator of the uncoupling protein.
D002001:Adipose Tissue, Brown / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D002352:Carrier Proteins; D002712:Chlorides / Q000378:metabolism; D006224:Cricetinae; D004024:Dicyclohexylcarbodiimide / Q000494:pharmacology; D005227:Fatty Acids / Q000494:pharmacology*; D006153:Guanosine Diphosphate / Q000494:pharmacology; D066298:In Vitro Techniques; D007473:Ion Channels; D008565:Membrane Proteins / Q000378:metabolism*; D008647:Mesocricetus; D024101:Mitochondrial Proteins; D010171:Palmitoyl Coenzyme A / Q000494:pharmacology; D000071256:Uncoupling Protein 1
D002352:Carrier Proteins; D002712:Chlorides; D005227:Fatty Acids; D007473:Ion Channels; D008565:Membrane Proteins; D024101:Mitochondrial Proteins; D000071256:Uncoupling Protein 1; D006153:Guanosine Diphosphate; D010171:Palmitoyl Coenzyme A; D004024:Dicyclohexylcarbodiimide