Background

The cGMP pathway regulates a large spectrum of physio-logical processes including metabolism. Our aim is to elucidate the cGMP signaling cascade in adipose tissue. Two types of fat tissue can be distinguished in mammals: white adipose tissue (WAT), which is the biggest storage of energy, and brown fat (BAT) that can dissipate energy as heat (non-shivering thermogenesis). We and others found that cGMP enhances differentiation of brown and white adipocytes [1-4]. Methods and results In our studies, we initially focused on protein kinase G (PKG/cGK), which is expressed both in white and brown adipocytes. Using gain- and loss-of-function models, we found that PKG is the major receptor for cGMP in brown adipocytes. We investigated the downstream target