Abstract/Summary

Oestrogen receptors (ER) transduce the effects of the endogenous ligand, 17b-estradiol in cells to regulate a number of important processes such as reproduction, neuroprotection, learning and memory and anxiety. The ERa or ERb are classical intracellular nuclear hormone receptors while some of their variants or novel proteins such as the GPCR, GPER1/GPR30 are reported to localise in intracellular as well as plasma membrane locations. Though the brain is an important target for oestrogen with oestrogen receptors expressed differentially in various nuclei, subcellular organisation and crossttalk between these receptors is underexplored. Using an adapted protocol that is rapid, we first generated neurons from mouse embryonic stem cells. Our immunocytochemistry approach shows that the full length ERa (ERa-66) and for the first time, that an ERa variant, ERa-36, as well as GPER1 is present in embryonic stem cells. In addition, these receptors typically decrease their nuclear localisation as neuronal maturation proceeds. Finally, though these ERs are present in many subcellular compartments such as the nucleus and plasma membrane, we show that they are specifically not colocalised with each other, suggesting that they initiate distinct signalling pathways.