CREB1 and depressive disorder: Finally, it has to be clearly stated that all previous studies regarding the role of CREB in depression and antidepressant drug action have been carried out in multiple brain regions, while our mutation is focused on the origin sites of noradrenergic and serotonergic neurons in the central nervous system: in particular, the locus coeruleus (LC) and dorsal raphe (DR) nuclei.