title: Functional characterization of promoter region polymorphisms of human CYP2C19 gene.
abstract: CYP2C19 is an enzyme involved in the metabolism of several clinically important drugs. The variations in the CYP2C19 promoter region may alter the transcription of the gene by altering the interaction between the trans and cis-acting elements. In the present study, CYP2C19 promoter region with different variant alleles were cloned into a pGL-3 basic luciferase reporter vector and transfected into HepG2 cell lines. Subsequently, dual luciferase activity was measured to evaluate the activity of the promoter region. Gel shift assays with predicted binding sites for CCAAT displacement protein, activating transcription factor-2 and glucocorticoid receptor were performed. Results from this study indicate that few variations present in the putative cis-acting elements of the CYP2C19 promoter region such as -1442T>C, -779A>C and -98T>C -1498T>G and -828del>T alter the transcription of the gene. Specific binding with nuclear proteins was also observed in gel shift assays. This may account for the interindividual variations in gene expression and genotype dependant differences in gene transcription. The results also suggest the role of activating transcription factor-2 and CCAAT displacement repressor protein on CYP2C19 gene transcription.
authors.affiliation: Department of Pharmacology, Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Pondicherry, 605006, India. uchakradhar@gmail.com
authors.forename: Uppugunduri
authors.initials: U
authors.lastname: Satyanarayana Chakradhara Rao
authors.forename: Anichavezhi
authors.initials: A
authors.lastname: Devendran
authors.forename: Kapettu
authors.initials: K
authors.lastname: Satyamoorthy
authors.forename: Deepak Gopal
authors.initials: DG
authors.lastname: Shewade
authors.forename: Rajgopal
authors.initials: R
authors.lastname: Krishnamoorthy
authors.forename: Adithan
authors.initials: A
authors.lastname: Chandrasekaran
mesh_terms: D001189:Aryl Hydrocarbon Hydroxylases / Q000235:genetics*; D065731:Cytochrome P-450 CYP2C19; D004247:DNA / Q000378:metabolism; D024202:Electrophoretic Mobility Shift Assay; D017930:Genes, Reporter / Q000235:genetics; D056426:Genetic Loci / Q000235:genetics; D005822:Genetic Vectors; D056945:Hep G2 Cells; D006801:Humans; D008156:Luciferases / Q000378:metabolism; D011110:Polymorphism, Genetic; D011401:Promoter Regions, Genetic
chemical_list: D004247:DNA; D008156:Luciferases; D001189:Aryl Hydrocarbon Hydroxylases; C045793:CYP2C19 protein, human; D065731:Cytochrome P-450 CYP2C19