THE NGFI-B SUBFAMILY OF THE NUCLEAR RECEPTOR SUPERFAMILY (REVIEW)

NGFI-B, Nurr1 and NOR-1 have structural features of ligand-activated t ranscriptional regulators and constitute the NGFI-B subfamily within t he nuclear receptor superfamily. Since specific ligands for these mole cules have not yet been identified, they are often called orphan nucle ar receptors. Genes of the NGFI-B subfamily are classified as immediat e-early genes that are induced rapidly but transiently by a variety of stimuli. Evidence accumulated over the past decade suggests this subf amily is involved in important physiological processes and cancer deve lopment. In this communication, we summarize and discuss their structu ral features, gene expression, physiological roles and oncological sig nificance.