Linked Life Data

11222153

Source:http://linkedlifedata.com/resource/pubmed/id/11222153

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2001-3-6
pubmed:abstractText
Early in Drosophila embryogenesis, transcriptional repressors encoded by Gap genes prevent the expression of particular combinations of Hox genes in each segment. During subsequent development, those Hox genes that were initially repressed in each segment remain off in all the descendent cells, even though the Gap repressors are no longer present. This phenomenon of heritable silencing depends on proteins of the Polycomb Group (PcG) and on cis-acting Polycomb response elements (PREs) in the Hox gene loci. We have removed individual PcG proteins from proliferating cells and then resupplied these proteins after a few or several cell generations. We show that most PcG proteins are required throughout development: when these proteins are removed, Hox genes become derepressed. However, we find that resupply of at least some PcG proteins can cause re-repression of Hox genes, provided that it occurs within a few cell generations of the loss of repression. These results suggest a functional distinction between transcriptional repression and heritable silencing: in at least some contexts, Hox genes can retain the capacity to be heritably silenced, despite being transcribed and replicated. We propose that silenced Hox genes bear a heritable, molecular mark that targets them for transcriptional repression. Some PcG proteins may be required to define and propagate this mark; others may function to repress the transcription of Hox genes that bear the mark.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0950-1991
pubmed:author
pubmed:issnType
Print
pubmed:volume
128
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
993-1004
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Polycomb group proteins and heritable silencing of Drosophila Hox genes.
pubmed:affiliation
Max-Planck-Institut für Entwicklungsbiologie, Spemannstr. 35/III, 72076 Tübingen, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't