ABSTRACT
Small and newborn mammals possess brown adipose tissue (BAT) a tissue specialized for the production of heat, which is important for the maintenance of body temperature during cold exposure and awakening from hibernation. Heat production in BAT is due to a controlled uncoupling of the mitochondrial respiratory chain. It has been shown for some time that the cold-induced increase in uncoupling protein (UCP) expression in BAT is mainly mediated by norepinephrine. The only real qualitative difference known so far is the expression of UCP in brown adipocytes and its absence in white adipocytes. The chapter investigates regulatory elements in the UCP gene promoter by transfection of brown adipocytes with different promoter regions coupled to a reporter gene and by construction of transgenic animals. It discusses results obtained by in vitro studies on primary cultures of brown preadipocytes from different species and on hibernating IB cells.
