Endogenous mutations in human uncoupling protein 3 alter its functional properties

Human uncoupling protein 3 (UCP3) is a mitochondrial transmembrane carrier that uncouples oxidative phosphorylation and is a candidate gene for obesit y. Expression of native human UCP3 mutations in yeast showed complete loss (R70W), significant reduction (R143X), or no effect (V102I and IVS6+1G>A) o n the uncoupling activity of UCP3, It is concluded that certain mutations i n UCP3 alter its functional impact on membrane potential (Delta Psi), possi bly conferring susceptibility to develop metabolic diseases, (C) 1999 Feder ation of European Biochemical Societies.