Anti-Estrogen Receptor alpha (ER alpha, Estradiol receptor, NR3A1)

ERa is a 65-70kD member of the NR3 subfamily, nuclear hormone receptor family of proteins. It is widely expressed, and serves as a strong activator of estrogen-responsive genes. ERa is normally quiescent and bound to heat-shock proteins and immunophilins. Following b-estradiol binding, it becomes activated, either homodimerizes or heterodimerizes with ERb, and binds to DNA with multiple coactivators. Human ERa is 595aa in length. It contains a DNA binding region aa185-250, three NLSs aa256-260, 266-271, 299-303, a steroid-binding site aa351-543, a dimerization motif aa497-518, and an O-GlcNAc attachment around Thr575. Major phosphorylation sites exist at Tyr537, Ser167 and Ser118. Multiple splice forms exist. There is an 80kD isoform that shows a substitution (duplication) of aa412-517 for Asp411, a second isoform with a deletion of aa255-366, a third isoform with a deletion of aa152-412, and a fourth isoform that shows a Thr substitution for aa152-595. Human ERa is only 46aa identical to human ERb. Over aa1-116, human ERa shares 85aa identity with mouse ERa. Applications: Suitable for use in Western Blot. Other applications not tested. Recommended Dilution: Western Blot: 0.05ug/ml, Optimal dilutions to be determined by the researcher. Storage and Stability: Lyophilized powder may be stored at -20°C. Stable for 12 months at -20°C. Reconstitute with PBS. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Reconstituted product is stable for 12 months at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.