Estrogen receptor α (ERα) is phosphorylated on multiple amino acid residues. For example,
in response to estradiol binding, human ERα is predominately phosphorylated on Ser-118
and to a lesser extent on Ser-104 and Ser-106. In response to activation of the mitogen-
activated protein kinase pathway, phosphorylation occurs on Ser-118 and Ser-167. These
serine residues are all located within the activation function 1 region of the N-terminal
domain of ERα. In contrast, activation of protein kinase A increases the phosphorylation of …