Finlay-Schultz_2011_J.Biol.Chem_286_42123

The CHRNA7 gene, which encodes the alpha7 nicotinic acetylcholine receptor (alpha7*nAChR), has been implicated as a candidate gene in schizophrenia. Expression of the alpha7*nAChR mRNA and protein are reduced in multiple regions of post-mortem brain from patients diagnosed with schizophrenia. Transcriptional regulation may therefore be an important mechanism for the regulation of this gene. A 230-bp proximal promoter fragment, necessary for transcription in cultured neuroblastoma cells, was used to study a putative AP-2alpha binding site. Mutation of the site indicates that AP-2alpha plays a negative role in regulating CHRNA7 transcription. This was confirmed through knockdown and overexpression of AP-2alpha. Electrophoretic mobility shift assays (EMSAs) identified positive DNA-protein interaction at this same site, and supershift assays indicate that the complex includes AP-2alpha. The interaction was confirmed in cells using chromatin immunoprecipitation (ChIP). DNA methylation was discovered as an anomalous mechanism for CHRNA7 regulation in one cell line. These studies suggest a role for AP-2alpha regulation of CHRNA7 mRNA expression in multiple tissues during development.