We have cloned and sequenced 1.8 kb of 5′ upstream sequence of CYP2C19. CYP 2C19 plays an important role in the metabolism of drugs such as omeprazole and phenytoin. Nothing is known about the mechanisms by which CYP2C19 gene is regulated because the upstream regulatory region of this gene had not been cloned. Promoter sequence was isolated from a human genomic library using the PCR-based GenomeWalker™ kit. Gene-specific primers derived from the exon 1 of CYP2C19 were used as the 3′ primers in the primary and nested amplification of the promoter. The nested PCR products were cloned into a TA cloning vector pT-Adv, sequenced by automated cycle sequencing, and confirmed by determination of contiguous genomic sequence of exonl of CYP2C19. Sequence analysis showed that the promoter of CYP2C19 contains a number of putative transcription factor sites, including HPF-1, GRE, ERE, Barbie Box, HNF-1, HNF4, AP-1 C/EBP, and GATA, in addition to a TATA box and a CAAT box. The sequence of the 5′-flanking region of the CYP2C19 gene was about 87% identical to that of the CYP2C9 promoter and had similar transcription factor sites. The sequence of an hPXR response element identified in the regulatory region of CYP3A4 was not found in either CYP2C19 or CYP2C9 despite the known effect of rifampin on the expression of these genes.
|Original language||English (US)|
|Journal||Clinical Pharmacology and Therapeutics|
|State||Published - Dec 1 2001|
ASJC Scopus subject areas
- Pharmacology (medical)