Figure 2 In genomic action, estrogen regulates the transcription of target genes by binding to and activating inactive ER receptors in the cytoplasm or nucleus, and the activated estrogen receptor monomer forms a dimer with another activated estrogen receptor monomer, which in combination with other co-regulatory proteins (not labeled) regulates the transcription of target genes after binding to the estrogen response element (ERE) within the DNA. Non-genomic action: Estrogen induces the initiation of estrogen action by binding to receptors on the cell membrane, which in turn regulates downstream protein expression by acting as second messengers and transcription factors. (Created using Adobe Illustrator CS6, Version 16.0.0.682, Adobe Systems, Incorporated).