Linked Life Data

11825903

Source:http://linkedlifedata.com/resource/pubmed/id/11825903

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
15
pubmed:dateCreated
2002-4-8
pubmed:abstractText
The transcription factor Pdx1 is expressed in the pancreatic beta-cell, where it is believed to regulate several beta-cell-specific genes. Whereas binding by Pdx1 to elements of beta-cell genes has been demonstrated in vitro, almost none of these genes has been demonstrated to be a direct binding target for Pdx1 within cells (where complex chromatin structure exists). To determine which beta-cell promoters are bound by Pdx1 in vivo, we performed chromatin immunoprecipitation assays using Pdx1 antiserum and chromatin from beta-TC3 cells and Pdx1-transfected NIH3T3 cells and subsequently quantitated co-immunoprecipitated promoters using real-time PCR. We compared these in vivo findings to parallel immunoprecipitations in which Pdx1 was allowed to bind to promoter fragments in in vitro reactions. Our results show that in all cells Pdx1 binds strongly to the insulin, islet amyloid polypeptide, glucagon, Pdx1, and Pax4 promoters, whereas it does not bind to either the glucose transporter type 2 or albumin promoters. In addition, no binding by Pdx1 to the glucokinase promoter was observed in beta-cells. In contrast, in in vitro immunoprecipitations, Pdx1 bound all promoters to an extent approximately proportional to the number of Pdx1 binding sites. Our findings suggest a critical role for chromatin structure in directing the promoter binding selectivity of Pdx1 in beta-cells and non-beta-cells.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
12
pubmed:volume
277
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
13286-93
pubmed:dateRevised
2011-6-1
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
Quantitative assessment of gene targeting in vitro and in vivo by the pancreatic transcription factor, Pdx1. Importance of chromatin structure in directing promoter binding.
pubmed:affiliation
Department of Medicine, Division of Endocrinology and Metabolism, University of Virginia Health Sciences Center, 1300 Jefferson Park Avenue, Charlottesville, VA 22908, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.