Insulin signaling in the adipocyte

Mammalian adipose tissue serves a number of functions, including storage of nutrients for periods of fasting and control of organismal metabolism. Cri tical to these functions is the capacity of the fat cell to respond to insu lin with a significant increase in glucose uptake. It is now generally reco gnized that the major site of action of insulin in this tissue is the mobil ization of a pool of latent, intracellular transport proteins. Nonetheless, the precise signaling pathways which mediate the insulin-stimulated increa se in glucose transport remain uncertain. In recent years, the serine/threo nine protein kinase Akt/PKB has emerged as an important candidate signaling molecule. Considerable current effort is being directed at trying to defin itively establish whether Akt/PKB is an important intermediate in insulin s ignaling to glucose transport in muscle and fat.