Linked Life Data

12644953

Source:http://linkedlifedata.com/resource/pubmed/id/12644953

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2003-3-19
pubmed:abstractText
Salivary gland polytene chromosomes of Drosophila melanogaster have a reproducible set of intercalary heterochromatin (IH) sites, characterized by late DNA replication, underreplicated DNA, breaks and frequent ectopic contacts. The SuUR mutation has been shown to suppress underreplication, and wild-type SuUR protein is found at late-replicating IH sites and in pericentric heterochromatin. Here we show that the SuUR gene influences all four IH features. The SuUR mutation leads to earlier completion of DNA replication. Using transgenic strains with two, four or six additional SuUR(+) doses (4-8xSuUR(+)) we show that wild-type SuUR is an enhancer of DNA underreplication, causing many late-replicating sites to become underreplicated. We map the underreplication sites and show that their number increases from 58 in normal strains (2xSuUR(+)) to 161 in 4-8xSuUR(+) strains. In one of these new sites (1AB) DNA polytenization decreases from 100% in the wild type to 51%-85% in the 4xSuUR (+) strain. In the 4xSuUR(+) strain, 60% of the weak points coincide with the localization of Polycomb group (PcG) proteins. At the IH region 89E1-4 (the Bithorax complex), a typical underreplication site, the degree of underreplication increases with four doses of SuUR(+) but the extent of the underreplicated region is the same as in wild type and corresponds to the region containing PcG binding sites. We conclude that the polytene chromosome regions known as IH are binding sites for SuUR protein and in many cases PcG silencing proteins. We propose that these stable silenced regions are late replicated and, in the presence of SuUR protein, become underreplicated.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0009-5915
pubmed:author
pubmed:issnType
Print
pubmed:volume
111
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
377-98
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Influence of the SuUR gene on intercalary heterochromatin in Drosophila melanogaster polytene chromosomes.
pubmed:affiliation
Institute of Cytology and Genetics, Siberian Division of Russian Academy of Sciences, Novosibirsk 630090, Russia. zhimulev@bionet.nsc.ru
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't