Eukaryotic gene transcription-studies on cytochrome P-450 as a model system

Abstract

Studies on the transcnptional regulation of the CYP2BIIB2 subfamily of the cytochrome P-450 supergene family have yielded valuable information. Major promoters regulating this gene are located in the near upstream of the 5' flanking region. Transcriptional regulation is modulated by both positive and negative cis-acting elements. It appears that phenobarbitone, the prototype inducer, may be regulating the phosphorylation status of the transcription factors, rather than acting through a specific phenobarbitone-responsive element on the gene. This concept is attractive in explaining the broad-based action of phenobarbitone and some other unrelated chemicals in activating a set of genes specifically as a short-term response and a global effect leading to hypertrophy as a long-term response.