Transcriptional activity analysis of promoter region of human PAX9 gene under dexamethasone, retinoic acid, and ergocalciferol treatment in MCF-7 and MDPC23.

Department of Morphology, Piracicaba Dental School, University of Campinas-Unicamp, Piracicaba, Sao Paulo, Brazil.
Cell Biochemistry and Function (Impact Factor: 1.85). 10/2010; 28(7):555-64. DOI: 10.1002/cbf.1688
Source: PubMed

ABSTRACT PAX9 gene is a member of the family homeobox of transcription factors and performs important function in development and organogenesis. Mutations in PAX9 coding sequences have been implicated in autosomal dominant oligodontia affecting predominantly permanent molars and second premolars. Previous studies have shown that PAX9 is required for secondary palate development and teratogens have been identified as inducers of a tooth and craniofacial malformations. This work focused on the analysis on the 5'-flanking region of the PAX9 gene studying the influence of retinoic acid, dexamethasone, and vitamin D on the expression of PAX9 by expression constructs that carry the reporter gene luciferase. As results, retinoic acid and dexamethasone showed progressive decrease of PAX9 expression. PAX9-pGL3B1 and PAX9-pGL3B2 promoter was inhibited under the treatment of dexamethasone and ergocalciferol. Retinoic acid and dexamethasone did not alter PAX9-pGL3B3 behavior indicating that sequences present between -1106 and +92 were important for the transcriptional activity of PAX9 promoter. In this study, we characterized the transcriptional activity of specific regions of the PAX9 promoter gene and we demonstrated that retinoic acid and ergocalciferol can modulate the transcriptional activity of PAX9 gene.

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