Regional distribution and cellular localization of the ETS-domain transcription factor, FEV, mRNA in the human postmortem brain

The ETS transcription factor Fifth Ewing Variant (FEV) mRNA, a homologue of the rodent Pet-1 gene that is exclusively expressed in serotonin-containing neurons and is a critical determinant of serotonin neuronal differentiation and development, was examined in human postmortem brain tissue using in situ hybridization histochemistry. Studies revealed that FEV mRNA is robustly and exclusively expressed in the major serotonin-containing cell groups of the dorsal and median raphe nuclei located in the midbrain and pons of the human brainstem. The localization of transcription factor, FEV, mRNA in serotomn-containing neurons of the human brain raises questions regarding the functional significance of this transcription factor in regulating serotonin-related genes and its potential role in psychiatric illness.