Estrogen Receptor Beta (ESR2) is a nuclear protein that belongs to the nuclear hormone receptor family of NR3 subfamily. It contains one nuclear receptor DNA-binding domain and is expressed in many tissues at a lower level. ESR2 is a nuclear hormone receptor. It binds estrogens with an affinity similar to that of ESR1 and activates expression of reporter genes containing estrogen response elements (ERE) in an estrogen-dependent manner. DNA-binding by ESR1 and ESR2 is rapidly lost at 37 degrees Celsius in the absence of ligand while in the presence of 17 beta-estradiol and 4-hydroxy-tamoxifen loss in DNA-binding at elevated temperature is more gradual.