Estrogen-related receptor gamma
Estrogen-related receptor gamma, also known as NR3B3, is a nuclear receptor that in humans is encoded by the ESRRG gene. It behaves as a constitutive activator of transcription.
This protein is a member of nuclear hormone receptor family of steroid hormone receptors. No physiological activating ligand is known for this orphan receptor, but 4-hydroxytamoxifen and diethylstilbestrol act as inverse agonists and deactivate ESRRG. It also seems to be the target of bisphenol A.There is evidence that bisphenol A functions as an endocrine disruptor by binding strongly to ERR-γ. BPA as well as its nitrated and chlorinated metabolites seems to binds strongly to ERR-γ, but not to the estrogen receptor., BPA binding to ERR-γ preserves its basal constitutive activity. It can also protect it from deactivation from the selective estrogen receptor modulator 4-hydroxytamoxifen.
Different expression of ERR-γ in different parts of the body may account for variations in bisphenol A effects. For instance, ERR-γ has been found in high concentration in the placenta, explaining reports of high bisphenol A accumulation there.
