Affinity gels for purification of retinoid-specific binding protein (RSBP)

Retinoids are defined as compounds which elicit specific biological effects such as control of cell growth and cell differentiation by binding to a specific receptor. Recently, we demonstrated the presence of a protein (RSBP) which satisfies the criteria for the retinoid receptor. For purification of RSBP, we prepared two types of affinity gels with retinoidal ligands (Gel-Am and Gel-Ch) based on synthetic retinobenzoic acids which possess very potent retinoidal activities. RSBP in the crude fraction extracted from cultured cells could be purified about 300-fold by affinity column chromatography using these affinity gels.