ESTROGEN RECEPTOR ALPHA (HUMAN ANTIBODY

Background/Target Information

Estrogen Receptors (ER) are members of the steroid family of nuclear receptors. There are two different forms of the estrogen receptor, alpha and beta, encoded by separate genes (ESR1 and ESR2, respectively). Each protein contains distinct functional domains required for transcriptional activation, binding to estrogen response elements (ERE) in DNA, constitutive dimerization, binding to heat shock proteins, and ligand recognition. ER is a ligand-activated transcription factor, that when bound to estrogen hormone, induces a conformational change that allows dimerization and binding to EREs. When bound to DNA, ER can positively or negatively regulate gene transcription through the recruitment of coactivator or corepressor proteins. There are several different isoforms of both ER alpha and ER beta. ER is an important regulator of growth and differentiation in the mammary gland. The presence of ER in breast tumors indicates an increased likelihood of response to anti-estrogen (e.g. tamoxifen) therapy.