Linked Life Data

1309295

Source:http://linkedlifedata.com/resource/pubmed/id/1309295

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1992-1-23
pubmed:abstractText
Treatment of wild-type (wt) aryl hydrocarbon (Ah)-responsive mouse Hepa 1c1c7 cells with benzo[a]pyrene (B[a]P) caused a concentration-dependent induction of ethoxyresorufin O-deethylase (EROD) activity. In contrast, B[a]P was inactive as an inducer in Ah nonresponsive class 1 and class 2 mutant cell lines. In parallel experiments, the nuclear fractions from wt cells treated with 10(-7) M [3H]B[a]P contained both the 4 s carcinogen binding protein and the 6 s (Ah receptor) complexes, whereas only the 4 s complex was present in the nuclear fraction of the class 2 mutant cells. The results obtained from cotreatment of wt Hepa 1c1c7 cells with 10(-6) or 10(-7) M B[a]P and 5 x 10(-7) or 10(-7) M 6-methyl-1,3,8-trichlorodibenzofuran (MCDF) showed that MCDF inhibited the induction of EROD activity and Cyp1a-1 mRNA levels by B[a]P. Moreover, using 10(-7) M [3H]B[a]P and unlabeled MCDF, it was shown that MCDF not only inhibited the induction response but also caused a concentration-dependent decrease in levels of the nuclear 6 s complex but not the 4 s complex. In contrast, in situ competition studies with unlabeled 10(-6) M benzo[ghi]-perylene (B[ghi]P) resulted in the elimination of the nuclear [3H]B[a]P 4 s complex (but not the 6 s complex); however, the EROD activity and Cyp1a-1 mRNA levels in cells treated with 10(-7) M B[a]P in the presence or absence of 10(-6) M B[ghi]P were not significantly different. These results indicate that the 4 s binding protein is not required for the induction of Cyp1a-1 gene expression in Hepa 1c1c7 cells and suggest that B[a]P and 2,3,7,8-tetrachlorodibenzo-p-dioxin induce Cyp1a-1 gene expression via a common mechanism which involves binding to the Ah receptor.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0003-9861
pubmed:author
pubmed:issnType
Print
pubmed:volume
292
pubmed:geneSymbol
Cyp1a-1
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
250-7
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed-meshheading:1309295-Animals, pubmed-meshheading:1309295-Base Sequence, pubmed-meshheading:1309295-Benzo(a)pyrene, pubmed-meshheading:1309295-Binding, Competitive, pubmed-meshheading:1309295-Carrier Proteins, pubmed-meshheading:1309295-Cell Line, pubmed-meshheading:1309295-Cytochrome P-450 CYP1A1, pubmed-meshheading:1309295-Cytochrome P-450 Enzyme System, pubmed-meshheading:1309295-Enzyme Induction, pubmed-meshheading:1309295-Gene Expression Regulation, Neoplastic, pubmed-meshheading:1309295-Glycine N-Methyltransferase, pubmed-meshheading:1309295-Liver Neoplasms, Experimental, pubmed-meshheading:1309295-Methyltransferases, pubmed-meshheading:1309295-Mice, pubmed-meshheading:1309295-Molecular Sequence Data, pubmed-meshheading:1309295-Nuclear Proteins, pubmed-meshheading:1309295-Oxidoreductases, pubmed-meshheading:1309295-Receptors, Aryl Hydrocarbon, pubmed-meshheading:1309295-Receptors, Drug
pubmed:year
1992
pubmed:articleTitle
Mechanism of benzo[a]pyrene-induced Cyp1a-1 gene expression in mouse Hepa 1c1c7 cells: role of the nuclear 6 s and 4 s proteins.
pubmed:affiliation
Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station 77843.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't