Fig. 2.

Sex steroid hormone receptor signaling pathway. (A) Schematic molecular structure of ERα and AR. Their functional domains are represented: the DNA Binding Domain (DBD), the Ligand Binding Domain (LBD) and the two transcriptional activation functions 1 and 2 (AF-1 and AF-2). (B, C) ERα and AR mode of action. (B) Hormone receptors can be activated in a ligand dependent manner either through direct binding of the receptor to hormone responsive element (HRE) on DNA or indirectly through association with transcription factors. Hormone can also trigger rapid non genomic activation of membrane-bound receptor generating second messengers. (C) Receptors can be also activated in a ligand-independent manner through kinase-dependent activation downstream of cytokine or growth factors receptors.