Gene UCP3
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Also known as
Uncoupling protein 3, SLC25A9Overview
UCP3 (Uncoupling Protein 3) encodes a mitochondrial uncoupling protein predominantly expressed in skeletal muscle and, to a lesser extent, in brown adipose tissue and the heart. Like UCP2, UCP3 facilitates proton leak across the inner mitochondrial membrane, dissipating the proton gradient and releasing energy as heat rather than storing it as ATP. This process reduces metabolic efficiency while also limiting reactive oxygen species production during fatty acid oxidation.Genetic variants in UCP3 have been associated with differences in resting metabolic rate, exercise efficiency, and body composition. Higher UCP3 expression may increase energy expenditure and fat oxidation during exercise, potentially benefiting endurance performance but reducing exercise economy. Conversely, lower UCP3 activity may enhance ATP production efficiency, which could be advantageous for strength and power activities but may also increase oxidative stress during intense exercise.
UCP3 appears to play an important role in protecting muscle from lipotoxicity by facilitating the export of fatty acid anions from mitochondria when fat supply exceeds oxidative capacity. Understanding UCP3 genetics can inform personalized training strategies, dietary macronutrient ratios, and recovery protocols to optimize athletic performance and metabolic health.