Characterization and Transcriptional Control of the Rabbit Cytochrome P450pbii Genes (Evolution, Isozymes)

The phenobarbital (PB)-inducible cytochrome P-450(P-450) family is tentatively divided into the PBI (including rat P-450s b and e, and rabbit P-450 (form 2)), and PBII (including rabbit P-450s PBc1, PBc2, PBc3 (form 3b), PBc4 and (form 1)) subfamilies that are 55-60% homologous in their protein coding regions. The structures of the P-450PBII genes have been determined by restriction mapping and DNA sequencing lambda phage genomic clones corresponding to the genes for P-450PBc2, P-450PBc3 and P-450 (form 1). Comparison of the cloned genomic sequences with cDNA sequences established that genomic clone 6 contained the 5'-flanking region and the first six exons of the P-450PBc2 gene. Genomic clones 25 and 31 contained exons 7 through 9, and 3'-flanking regions of P-450PBc3 and P-450 (form 1) genes respectively. The locations of intron-exon junctions relative to the coding sequence in these genes are identical to the genes of the PBI subfamily, but completely different from the 3-methyl-cholanthrene inducible genes, suggesting that genes within the PB-inducible family arose by divergent evolution. The derived sequences of the first 20-22 N-terminal amino acids of the P-450PBc2 is 65% similar to the rabbit isozymes, form1, and form 3b, and rat isozymes, f, g, h, i and PB1, indicating that the rat isozymes probably belong to the PBII subfamily. The principal transcription initiation site of P-450PBc2 is 18 bp downstream from the TATA sequence, and 23 pb upstream from the translational initiator codon.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Biology

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2015

Author dc:creator

• Govind, Shubha

• Biology, General

Language dc:language

eng

Identifier

(UMI)AAI8701495

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/77644