Molecular Mechanisms of Retinoid Function

Abstract

Retinoids, derivatives of vitamin A, influence many aspects of cell and developmental biology, and may be important intracellular regulators or signaling molecules. This chapter attempts to outline current knowledge of how retinoids affect cell and tissue development with respect to their sites of absorption in the gut and journey to their final (but not necessarily sole) target-receptors within the cell nucleus that function mainly, although not exclusively, as ligand-dependent transcriptional regulators. While the emphasis is on all- trans retinoic acid, the potential biological role of the 9- cis isomer is stressed and the importance of other retinoids and mechanisms of retinoid action are outlined. Since retinoic acid affects many aspects of cell function, nuclear retinoic acid receptors are important targets for the development of new drugs and therapeutic strategies in medicine.