Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2002-4-18
pubmed:abstractText
Thyroid hormone [triiodothyronine (T3)] positively regulates NADPH cytochrome P450 reductase (P450R) mRNA expression in rat liver, with P450R transcription initiation being a key regulated step. T3 is presently shown to have significant post-transcriptional effects on P450R expression. T3 increased the size of cytoplasmic P450R mRNA by approximately 105 nucleotides 12 h after T3 treatment, followed by a return to basal levels at 24 h. Primer extension analysis and Northern hybridization with 5'-untranslated region probes revealed no change in P450R mRNA 5' structure with T3 treatment. By contrast, RNase H analysis revealed a transient, T3-induced increase in P450R mRNA poly(A) tail, from approximately 100 to approximately 205 A. This increase in P450R polyadenylation, detectable in the nucleus 8 h after T3 treatment and in the cytoplasm at 12 h, was transient and was reversed by 16 h, when the T3-induced accumulation of cytoplasmic P450R mRNA was near maximal. Actinomycin D blocked the increase in P450R poly(A) tail and the induction of P450R mRNA, indicating a requirement for ongoing gene transcription for both T3 responses. T3 treatment destabilized P450R mRNA in rat liver in vivo, as shown by the T3-dependent 6-fold decrease in cytoplasmic P450R mRNA half-life, from a basal value of >or=16 h in uninduced liver to approximately 2.5 h, measured 24 h after T3 administration. These findings demonstrate that T3 increases nuclear polyadenylation of P450R RNA as a transient, early regulatory response and that this response is temporally dissociated from the subsequent decrease in cytoplasmic P450R mRNA stability.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0026-895X
pubmed:author
pubmed:issnType
Print
pubmed:volume
61
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1089-96
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Post-transcriptional regulation of hepatic NADPH-cytochrome P450 reductase by thyroid hormone: independent effects on poly(A) tail length and mRNA stability.
pubmed:affiliation
Division of Cell and Molecular Biology, Department of Biology, Boston University, Boston, Massachusetts, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.