Linked Life Data

8630269

Source:http://linkedlifedata.com/resource/pubmed/id/8630269

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1996-7-1
pubmed:abstractText
Sublethal quinone-mediated oxidative stress stimulates increases in the activities and mRNA levels of gamma-glutamyl transpeptidase (GGT) and gamma-glutamylcysteine synthetase (GCS) in rat lung epithelial L2 cells [Kugelman, A. et al. 1994. Am. J. Respir. Cell Mol. Biol. 11:586-592; Shi, M. M. et al. 1994. J. Biol. Chem. 269:26512-26517]. The present study demonstrated that the quinone-induced increases in these two enzymes were differentially regulated. L2 cells were exposed to various concentrations of tertiary-butylhydroquinone (TBHQ) for different periods of times. TBHQ increased the activities and the mRNAs for GGT and the catalytic subunit of GCS; however, the time- and concentration-dependencies differed. With 50 microM TBHQ, GCS activity increased significantly by 6 h whereas the activity of GGT was not increased until later. Under the same conditions, the highest GCS-mRNA level observed was at 6 h whereas the mRNA level of GGT increased after 6 h, reached a higher level at 12 h, and then returned to the control level by 24 h. Differences were also observed in the concentration-dependence of mRNA increases between the GGT and GCS. Actinomycin D (an inhibitor of RNA synthesis) abolished the increase of GCS-mRNA but not the increase in GGT-mRNA, suggesting a difference in regulation by TBHQ between these two genes. Nuclear run-on experiments confirmed that the increase of GCS-mRNA, but not GGT-mRNA was due to increased transcription. The increase in GGT-mRNA probably results from a decreased degradation rate. The differences between these two enzymes demonstrate how cells can use multiple mechanisms for regulating gene expression in response to oxidative stress.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1044-1549
pubmed:author
pubmed:issnType
Print
pubmed:volume
14
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
186-91
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Differential enhancement of gamma-glutamyl transpeptidase and gamma-glutamylcysteine synthetase by tert-butylhydroquinone in rat lung epithelial L2 cells.
pubmed:affiliation
Department of Molecular Pharmacology and Toxicology, University of Southern California, Los Angeles 90033, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.