Serotonergic transcription of human FEV reveals direct GATA factor interactions and fate of Pet-1-deficient serotonin neuron precursors.
Altered expression of the human FEV (fifth Ewing variant) ETS transcription factor gene impacts the level of CNS serotonin (5-HT) neuron gene expression and maternal nurturing. However, the regulatory mechanisms that determine FEV expression are poorly understood. Here, we investigated the cis-regulatory control of FEV to begin to identify the upstream transcription factors that restrict FEV expression to 5-HT neurons. We find that sequences extending only 275 bp upstream of the FEV 5' untranslated region are sufficient to direct FEV transgene expression to embryonic 5-HT neurons, although sequences farther upstream are required for maintenance in adult 5-HT neurons. Two highly conserved consensus GATA factor binding sites within the 275 bp region interact with GATA factors in vitro. Chromatin immunoprecipitations with embryonic hindbrain demonstrated Gata-2 interactions with the orthologous mouse Pet-1 ETS cis-regulatory region. Mutagenesis of GATA sites revealed that one or the other site is required for serotonergic FEV transgene expression. Unexpectedly, FEV-LacZ transgenes enabled determination of 5-HT neuron precursor fate in the adult Pet-1(-/-) dorsal and median raphe nuclei and thus provided additional insight into FEV/Pet-1 function. Comparable numbers of FEV-LacZ-positive cells were detected in Pet-1(+/-) and Pet-1(-/-) adult dorsal raphe nuclei, indicating that the majority of mutant serotonergic precursors are not fated to apoptosis. However, B7 dorsal raphe cells were aberrantly distributed, suggesting a role for FEV/Pet-1 in their midline organization. Our findings identify a direct transcriptional interaction between Gata-2 and FEV and a unique marker for new insight into FEV/Pet-1 function in 5-HT neuron development.
Krueger
Katherine C
KC
Department of Neurosciences, Case Western Reserve University, School of Medicine, Cleveland, Ohio 44106, USA.
Deneris
Evan S
ES
D020121:5' Untranslated Regions / Q000235:genetics; D000818:Animals; D017209:Apoptosis / Q000235:genetics; D001933:Brain Stem / Q000166:cytology / Q000196:embryology / Q000378:metabolism; D015815:Cell Adhesion Molecules; D004268:DNA-Binding Proteins / Q000235:genetics*; D050980:GATA Transcription Factors / Q000235:genetics*; D050989:GATA2 Transcription Factor / Q000235:genetics; D018507:Gene Expression Regulation, Developmental / Q000235:genetics; D017930:Genes, Reporter / Q000235:genetics; D006801:Humans; D007136:Immunoglobulins / Q000235:genetics / Q000502:physiology*; D007763:Lac Operon / Q000235:genetics; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology*; D051379:Mice; D018345:Mice, Knockout; D055495:Neurogenesis / Q000235:genetics; D009474:Neurons / Q000378:metabolism*; D009687:Nuclear Proteins / Q000235:genetics*; D011903:Raphe Nuclei / Q000166:cytology / Q000196:embryology / Q000378:metabolism; D050436:Regulatory Elements, Transcriptional / Q000235:genetics; D012701:Serotonin / Q000378:metabolism*; D013234:Stem Cells / Q000166:cytology / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics*; D014158:Transcription, Genetic / Q000235:genetics
D020121:5' Untranslated Regions; D015815:Cell Adhesion Molecules; D004268:DNA-Binding Proteins; C474280:FEV protein, human; D050980:GATA Transcription Factors; D050989:GATA2 Transcription Factor; C494712:Gata2 protein, mouse; C498600:Igsf4b protein, mouse; D007136:Immunoglobulins; D008565:Membrane Proteins; D009687:Nuclear Proteins; D014157:Transcription Factors; D012701:Serotonin