Estrogen receptors (ER) are nuclear receptors that mediate the actions of the endogenous steroid hormone, 17β-estradiol (E2). ER is synthesized as two protein forms, ERα and ERβ, which can bind to the estrogen receptor element (ERE) as homo- or heterodimers. Cell proliferation and differentiation triggered by ER activation has been heavily studied in bone-wasting and breast cancer treatments. The TransAM ER Kit contains an antibody specific for the active form of ERα when it is bound to the target DNA.

