Effects of pyridoxal 5'-phosphate on uterine estrogen receptor. II. Inhibition of estrogen . receptor transformation.

摘要: Previous observations suggested that pyridoxal 5'-phosphate was capable of inhibiting estrogen . receptor (R E2) activation, or translocation to the nucleus, both. The present study attempts define more specifically locus this action. To end we have examined physicochemical alteration produced by interaction with complex, using sucrose density gradient analysis and dissociation kinetics. Receptor transformation inhibited when activation performed in presence 5'-phosphate. This effect protein- concentration-dependent. When introduced postactivation it did not any on activated receptor, but similar treatment followed NABH4 reduction, complex reverted monomeric entity. behavior obtained cytosol R E2, warmed 5'-phosphate, showed a biphasic curve suggesting significant portion receptors remained nonactivated as demonstrated fast dissociating component. Due fact Tris buffers cannot be used for experiments, borate buffer which resulted displacement sedimentation values from 4S 4.6 S unactivated 5S 6 form. reported suggest at least initial results inhibition cytosolic