Abstract
The uncoupling protein found in mitochondria from thermogenic brown adipose tissue is structurally very similar to two other mitochondrial carrier proteins transporting ADP/ATP and phosphate, respectively. Similarities are also seen with the mechanism of these carriers, which are part of a family of H+/OH-substrate anion co-transporters, further strengthening the evidence that the uncoupling protein has evolved from this family of mitochondrial carrier proteins.