RESUMO
Valproic acid (VPA), a widely used antiepileptic drug, is characterized by intensive inter-individual variability in concentration. Both efflux and influx transporters are reported to play important roles in the disposition of VPA, however, no comprehensive investigation into the association of the single nucleotide polymorphism (SNP) in ABC/SLC families with VPA concentration are reported. In the present study, we investigated the association of 12 SNPs in ABCC2, ABCC4, ABCG2, MCT1, MCT2, and OATP2B1 in 187 Chinese patients with epilepsy on VPA monotherapy with the trough concentrations of VPA. The data showed that VPA concentration in patients with ABCC2 rs2273697 AA genotype was significantly higher than that in those with GA+GG genotypes (p=0.000). The findings of the present study suggest that ABCC2 polymorphisms influence VPA concentrations in patients with epilepsy on VPA monotherapy, which may affect the treatment outcomes.
Assuntos
Anticonvulsivantes/farmacocinética , Epilepsia/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Ácido Valproico/farmacocinética , Adulto , Anticonvulsivantes/administração & dosagem , Povo Asiático/genética , Epilepsia/tratamento farmacológico , Epilepsia/metabolismo , Feminino , Genótipo , Humanos , Masculino , Proteína 2 Associada à Farmacorresistência Múltipla , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Polimorfismo de Nucleotídeo Único , Resultado do Tratamento , Ácido Valproico/administração & dosagem , Adulto JovemRESUMO
Transcription factors (TFs) play critical roles in the development of the nervous system, but the transcriptional regulatory mechanisms of these genes are poorly understood. Here we analyzed 5-kb of the 5' flanking genomic DNA sequences of 41 TF genes involved in neuronal development. The results showed that the TF genes tend to have higher GC contents in the proximal region and most of the TF genes have at least one proximal GC-rich (GC content > 60%) promoter with a CpG island. The promoter distribution analysis showed that the GC-poor promoters were sporadically distributed within the 5-kb flanking genomic sequence (FGS); however, more than half (37 of 70) of the GC-rich promoters were located in the proximal region between nucleotides -1 and -500. Luciferase assays showed that partial GC-rich promoters increased gene expression in SH-SY5Y cells and that CpG methylation repressed the promoter activity. This study suggests a potential general mechanism for regulation of TF expression.
Assuntos
Ilhas de CpG/genética , Sistema Nervoso/embriologia , Regiões Promotoras Genéticas/genética , Fatores de Transcrição/genética , Composição de Bases/genética , Sequência de Bases , Linhagem Celular Tumoral , Metilação de DNA/genética , Regulação da Expressão Gênica no Desenvolvimento/genética , Humanos , Dados de Sequência MolecularRESUMO
Voltage-gated sodium channel α-subunit type III (Na(v)1.3) is mainly expressed in the central nervous system and is associated with neurological disorders. The expression of mouse Scn3a product (Na(v)1.3) mainly occurs in embryonic and early postnatal brain but not in adult brain. Here, we report for the first time the identification and characterization of the mouse Scn3a gene promoter region and regulation of the promoter activity by GC box and CpG methylation. Luciferase assay showed that the promoter region F1.2 (nt -1,049 to +157) had significantly higher activity in PC12 cells, comparing with that in SH-SY5Y cells and HEK293 cells. A stepwise 5' truncation of the promoter region found that the minimal functional promoter located within the region nt -168 to +157. Deletion of a GC box (nt -254 to -258) in the mouse Scn3a promoter decreased the promoter activity. CpG methylation of the F1.2 without the GC box completely repressed the promoter activity, suggesting that the GC box is a critical element in the CpG-methylated Scn3a promoter. These results suggest that the GC box and CpG methylation might play important roles in regulating mouse Scn3a gene expression.
Assuntos
Ilhas de CpG , Metilação de DNA , Fosfatos de Dinucleosídeos/metabolismo , Regiões Promotoras Genéticas/genética , Canais de Sódio/genética , Animais , Linhagem Celular Tumoral , Regulação da Expressão Gênica , Humanos , Camundongos , Mutagênese Sítio-Dirigida , Canal de Sódio Disparado por Voltagem NAV1.3RESUMO
FMR1 gene plays an important role in the development of central nervous system. Down-regulation of the FMR1 expression leads to fragile X syndrome. MicroRNAs (miRNAs) can repress gene expression by base pairing with their mRNA targets. By computer programs analysis, five miRNAs: miR-19a, miR-19b, miR-142, miR-302b* and miR-323-3p potentially target to different sites on the FMR1 3' untranslated region (3' UTR), except that miR-19a and miR-19b share the same targeting site. To test whether these miRNAs repress reporter gene expression by interacting with the miRNA targets on the FMR1 3' UTR, we developed two chimeric constructs: one construct expressing a firefly luciferase with the FMR1 3' UTR or its miRNA target mutations and the other construct expressing a pre-miRNA fusing with GFP. Luciferase assay co-transfecting with the two constructs showed that the miRNAs, miR-19b, miR-302b* and miR-323-3p could repress gene expression in HEK-293 cells, suggesting a role of these miRNAs in the regulation of the FMR1 expression. The constructs used in this study can be widely used to identify the miRNA targets in any interested genes, which will greatly promote the current progress in understanding the biological function of miRNAs.
