Transcriptional regulation of basal and phenobarbital-mediated expression of rat cytochrome 2B genes

Cytochromes P450 2B1 and 2B2 (CYP2B1 and CYP2B2) are well known phenobarbital inducible genes in rat liver. Potential transcriptional regulatory elements in the proximal promoter regions of rat CYP2B genes were analyzed by transfection in HepG2 cells and by binding of nuclear proteins. Deletion of sequences from $-$110 to $-$57 markedly decreased the transcriptional activity, suggesting the presence of strong cis-acting elements in this region. Sequences similar to a basal transcription element (BTE), and a Barbie box are present from $-$89 to $-$67. However, no protection was detected in these regions by DNase I footprinting assay. Instead, a region (FP1) from $-$64 to $-$45 was protected by liver nuclear extracts. Mutation of either the BTE or FP1 sequences of CYP2B1 reduced transcriptional activity in HepG2 cells. FP1 was identified as a functional CCAAT/enhancer binding proteins (C/EBP) site by cotransfection of C/EBP expression vectors and supershift assays with C/EBP antisera.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Molecular and Integrative Physiology

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2011

Author dc:creator

• Park, Youngkyu

Contributors dc:contributor

• Kemper, Byron W.

• Biology, Molecular

Statement dc:rights

• Copyright 1996 Park, Youngkyu

Language dc:language

eng

Identifier

9780591198638
AAI9712397
(UMI)AAI9712397

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/20367