ORPHAN NUCLEAR RECEPTOR RZR-BETA - CYCLIC-AMP REGULATES EXPRESSION INTHE PINEAL-GLAND

The nuclear orphan receptor RZR beta is highly expressed in the rat pi neal gland. Recent studies proposed that melatonin, the pineal hormone which regulates a wide variety of circadian-linked phenomena, may be the natural ligand of this receptor. These provocative reports prompte d us to learn more about RZR beta and how it might function in circadi an physiology. Here we confirm high expression of this receptor in the pineal gland, and report that pineal RZR beta expression exhibits a s trong daily rhythm. Expression is under photoneural regulation and inv olves an adrenergic --> cAMP mechanism. (C) 1996 Academic Press, Inc.