CIDE-A, a novel link between brown adipose tissue and obesity

Brown adipose tissue (BAT) is the major site of adaptive thermogenesis in rodents. The thermogenic activity of BAT is mediated by uncoupling proteins (Ucp1). Impaired BAT activity is believed to have an important role in the development of obesity. However, direct evidence linking BAT to obesity is scarce. Cidea, which was initially identified as a result of its sequence similarity to the apoptotic DNA fragmentation factor, is highly expressed in BAT. Mice that are deficient for Cidea showed an increase in energy expenditure and are resistant to high-fat diet-induced obesity and diabetes. Although the precise mechanism by which Cidea regulates energy homeostasis is not yet clear, Cidea appears to interact with Ucp1 in mammalian cells and inhibits its uncoupling activity when co-expressed in yeast. Therefore, Cidea offers a new option to explore the linkage between BAT and obesity.