Signaling themes shared between peptide and steroid hormones at the plasma membrane

Abstract

Steroid hormone receptors are primarily thought of as transcriptional regulators that are activated by ligand binding. However, there is also evidence for "nongenomic" actions of steroid hormones. Cheryl Watson summarizes a recent meeting that brought together researchers exploring these rapid effects of steroid hormones that occur in the absence of new protein synthesis. Current evidence for the existence of membrane steroid receptors, which may or may not be related to the well-known nuclear receptors, is discussed.

Fig. 1

Steroids acting through membrane receptors can initiate many different forms of cellular signaling with both genomic and nongenomic consequences. Membrane receptor forms can be modified versions of their nuclear receptor counterparts or can be unrelated proteins. Proteins may interact with these receptors in the cell membrane to bring about diverse biological consequences, depending on the hormonal and cellular contexts. BP, binding protein.