Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
2003-12-9
pubmed:abstractText
To elucidate the earliest molecular steps in the activation of transcription by the progesterone receptor (PR), we investigated its activity in a cell-free transcription system utilizing chromatin templates. PR prepared as a ligand-free, recombinant protein failed to induce transcription on chromatin templates. However, transcriptional competence could be restored by coincubation with rabbit reticulocyte lysate (RRL). The interaction of PR with chaperones results in a receptor conformation competent to bind ligand and RRL contains abundant chaperone-mediated protein folding activity. Blocking this activity with the specific inhibitor geldanamycin inhibited receptor-dependent transcriptional activity. However, recombinant chaperones could not replace RRL in the restoration of transcriptional activity on chromatin templates, suggesting the presence of an additional activity in the lysate. Under chromatin assembly conditions, PR could bind naked DNA and RRL did not increase that binding. In contrast, PR bound to a chromatin template only poorly. Interestingly, RRL stimulated sequence-specific binding by PR to target sites in chromatin and the concomitant recruitment of the steroid receptor coactivator 1 to the promoter. Thus, our results indicate that a novel protein-mediated activity in RRL is involved in an additional, heretofore unrecognized, activation step required for PR to become transcriptionally competent on chromatin templates.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0888-8809
pubmed:author
pubmed:issnType
Print
pubmed:volume
17
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2543-53
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Novel activation step required for transcriptional competence of progesterone receptor on chromatin templates.
pubmed:affiliation
Department of Pathology B216, University of Colorado Health Sciences Center, 4200 East Ninth Avenue, Denver, Colorado 80262, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.