RESUMO
The 5' flanking region of the rat PB-inducible CYP2B1 gene was isolated and the sequence from +27 to -3878 was determined. This sequence contains several putative binding sites for the liver-enriched factors HNF3 as well as an AP1, two NF-kappa B and several possible STAT sites. The promoter sequence of the CYP2B1 gene was compared to that of the CYP2B2 sequence, published by Hoffman et al. ((1992) Gene Exp. 2, 353-362) and was found to be almost identical up to -2300 bp, beyond which it diverges significantly from the remaining published sequence of CYP2b2 gene. Transient transfection experiments in the differentiated hepatoma cell line, FGC4, showed that the 3.9 kb promoter was expressed, however, an increase in reporter activity was not observed in the presence of phenobarbital.
Assuntos
Hidrocarboneto de Aril Hidroxilases , Sistema Enzimático do Citocromo P-450/genética , Regiões Promotoras Genéticas , Esteroide Hidroxilases/genética , Animais , Sequência de Bases , Sítios de Ligação/genética , Linhagem Celular , DNA/genética , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Neoplasias Hepáticas Experimentais/genética , Neoplasias Hepáticas Experimentais/metabolismo , Dados de Sequência Molecular , Fenobarbital/farmacologia , Ratos , Homologia de Sequência do Ácido Nucleico , Fatores de Transcrição/metabolismo , TransfecçãoRESUMO
V79 derived Chinese hamster cells lines with specific xenobiotica metabolising functions were constructed by gene technological means. The significance of these cell lines as a test system in toxicology and pharmacology has been demonstrated by the evaluation of metabolite profiles of pharmaceuticals and xenobiotica, and the mutagenic and cytotoxic potency of the metabolites under defined and reproducible conditions.