Identification of a NFB responsive element within the dimethylarginine dimethylaminohydrolase 2 gene promoter / 中华医学遗传学杂志

ABSTRACT

<p><b>OBJECTIVES</b>To identify a NFB responsive element within the dimethylarginine dimethylaminohydrolase 2 gene (DDAH) promoter and demonstrate its role in DDAH2 transactivation.</p><p><b>METHODS</b>DDAH2 promoter was analyzed with software to identify potential binding sites of transcription factors. A series of truncated DDAH2 promoter luciferase reporter plasmids were constructed and transfected into human embryonic kidney derived HEK293 cells. Luciferase assays were carried out to analyze the activity of the promoter. Electrophoresis mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP) were used to identify the NFB responsive element in vitro and in vivo. DDAH2 promoter luciferase reporter plasmid with mutated NFB site was constructed and transfected into cells, and its activity was compared with that of the wild-type plasmid.</p><p><b>RESULTS</b>Potential bindings sites of many transcription factors were found within the DDAH2 promoter. The transcription activity of the DDAH2 promoter was high, and -530 to -437 was a positive regulating region. -476 to -469 of the DDAH2 promoter was a NFB responsive element, to which NFB can specifically bind. Mutation of the NFB element could significantly decrease the DDAH2 promoter activity.</p><p><b>CONCLUSION</b>-476 to -469 of the DDAH2 promoter was a NFB responsive element and is important for the transactivation of DDAH2.</p>