High Quality Content by WIKIPEDIA articles! Thermogenin (called uncoupling protein by its discoverers and now known as uncoupling protein 1, or UCP1) is an uncoupling protein found in the mitochondria of brown adipose tissue (BAT). It is used to generate heat by non-shivering thermogenesis. Non-shivering thermogenesis is the primary means of heat generation in hibernating mammals and in human infants.