Regulates metabolic homeostasis in response to nutritional cues and may therefore be involved in adaptation to dietary variations. May not function in creating mitochondrial proton leaks across the inner mitochondrial membrane (i.e. mitochondrial uncoupling). Expression levels are higher in the head than the body. Expressed throughout development. Expression levels are very weak, but increase in the adult stages. No visible phenotype. Reduced levels of total sugars (glucose and trehalose) in normal-fed flies and increased susceptibility to starvation. Life span is increased when fed a low-calorie diet and flies gain less weight when fed a high-calorie diet. Females lay a lower proportion of eggs, particularly under a restricted diet. Glycogen and triacylglyceride (TAG) levels are not affected in normal-fed flies. However, TAG levels decrease at a faster rate under starvation conditions. No increase in life span when fed a high-calorie diet or under starvation conditions. Belongs to the mitochondrial carrier (TC 2.A.29) family. Functions as a mitochondrial uncoupling protein when expressed in yeast.