Interaction of human estrogen receptors alpha and beta with the same naturally occurring estrogen response elements

Estrogen receptors are derived from two different gene products referred to as estrogen receptor-alpha (ER-alpha) and ER-beta. Both receptors bind to the consensus estrogen response element (ERE) present in the vitellogenin g ene, but their binding to hormone response elements present in other estrog en responsive genes has not been reported yet. Using in vitro expressed hum an receptors, we now show that ER-beta binds to a panel of six endogenous h ormone response elements (vitellogenin, c-fos, c-jun, pS2, cathepsin D, and choline acetyltransferase) already known to bind ER-cl and confer estrogen inducibility to reporter constructs. Binding of ER-alpha and ER-beta occur red at similar DNA concentrations for some EREs, but different DNA concentr ations were required to form complexes of the two receptors with other elem ents. These results illustrate for the first time by direct receptor-DNA bi nding studies that both ER-alpha and ER-beta bind to a number of EREs prese nt in endogenous hormone regulated genes, and further suggest that the two forms of the receptor display different patterns of affinities for naturall y occurring hormone response elements. (C) 1999 Elsevier Science Inc.