The Subcellular Localization and Physiological Roles of Estrogen Receptors α and β in Classical and Non-Classical Tissues

Abstract

It is now firmly established that estrogens elicit a variety of rapid effects in many tissues in addition to their delayed action on gene expression in the cell nucleus. Moreover, the classic estrogen receptors have been shown to act on signaling cascades. In this chapter we summarize various aspects of estradiol signaling, with special emphasis in the fast action of the hormone. We first concisely describe the traditional mechanism of action of the steroid and include new data about receptor structural features, its cellular localization, targets and role in classical and non-classical tissues. Moreover, we have compared the structure of the different estrogen receptors and how they are activated by distinct mechanisms. The likely interactions of non-classical estrogen receptors with other local proteins and their relationships with rapid signaling pathways triggered by estradiol are also discussed.