Linked Life Data

18948129

Source:http://linkedlifedata.com/resource/pubmed/id/18948129

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2008-12-16
pubmed:abstractText
The present study focuses on the molecular mechanism and interspecies differences in susceptibility of avian aryl hydrocarbon receptor (AHR)-cytochrome P4501A (CYP1A) signaling pathway. By the cloning of 5'-flanking regions of CYP1A5 gene from common cormorant (Phalacrocorax carbo) and chicken (Gallus gallus), seven putative xenobiotic response elements (XREs) were identified within 2.7 kb upstream region of common cormorant CYP1A5 (ccCYP1A5), and six XREs were found within 0.9 kb of chicken CYP1A5 (ckCYP1A5). Analysis of sequential deletion and mutagenesis of the binding sites in avian CYP1A5 genes by in vitro reporter gene assays revealed that two XREs at -613 bp and -1585 bp in ccCYP1A5, and one XRE at -262 bp in ckCYP1A5 conferred TCDD-responsiveness. The binding of AHR1 with AHR nuclear translocator 1 (ARNT1) to the functional XRE in a TCDD-dependent manner was verified with gel shift assays, suggesting that avian CYP1A5 is induced by TCDD through AHR1/ARNT1 signaling pathway as well as mammalian CYP1A1 but through a distinct pathway from mammalian CYP1A2, an ortholog of the CYP1A5. TCDD-EC(50) for the transcriptional activity in both cormorant AHR1- and AHR2-ccCYP1A5 reporter construct was 10-fold higher than that in chicken AHR1-ckCYP1A5 reporter construct. In contrast, chicken AHR2 showed no TCDD-dependent response. The TCDD-EC(50) for CYP1A5 transactivation was altered by switching AHR1 between the two avian species, irrespective of the species from which the regulatory region of CYP1A5 gene originates. Therefore, the structural difference in AHR, not the CYP1A5 regulatory region may be a major factor to account for the dioxin susceptibility in avian species.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
1096-0333
pubmed:author
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
234
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1-13
pubmed:meshHeading
pubmed-meshheading:18948129-Animals, pubmed-meshheading:18948129-Aryl Hydrocarbon Hydroxylases, pubmed-meshheading:18948129-Base Sequence, pubmed-meshheading:18948129-Binding Sites, pubmed-meshheading:18948129-Birds, pubmed-meshheading:18948129-Chickens, pubmed-meshheading:18948129-Cloning, Molecular, pubmed-meshheading:18948129-Dose-Response Relationship, Drug, pubmed-meshheading:18948129-Electrophoretic Mobility Shift Assay, pubmed-meshheading:18948129-Enhancer Elements, Genetic, pubmed-meshheading:18948129-Environmental Pollutants, pubmed-meshheading:18948129-Mutagenicity Tests, pubmed-meshheading:18948129-Protein Isoforms, pubmed-meshheading:18948129-Receptors, Aryl Hydrocarbon, pubmed-meshheading:18948129-Response Elements, pubmed-meshheading:18948129-Sequence Analysis, DNA, pubmed-meshheading:18948129-Signal Transduction, pubmed-meshheading:18948129-Species Specificity, pubmed-meshheading:18948129-Tetrachlorodibenzodioxin, pubmed-meshheading:18948129-Transcription, Genetic
pubmed:year
2009
pubmed:articleTitle
Dioxin activation of CYP1A5 promoter/enhancer regions from two avian species, common cormorant (Phalacrocorax carbo) and chicken (Gallus gallus): association with aryl hydrocarbon receptor 1 and 2 isoforms.
pubmed:affiliation
Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho, Matsuyama, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't