[Adrenergic receptor signaling and regulation].

At the beginning, beta-arrestin is believed to regulate desensitization of G protein-coupled receptors. However, it becomes apparent that beta-arrestin is involved in not only regulation but also signal transduction by identification of many proteins interacting with beta-arrestin. So far, the model of regulation and signaling of G protein-coupled receptor is built on beta 2-adrenergic receptor. However, this model does not apply to all G protein-coupled receptors. The differential regulation and signaling between beta 1- and beta 2-adrenergic receptors is presented.