Linked Life Data

8064852

Source:http://linkedlifedata.com/resource/pubmed/id/8064852

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1994-9-20
pubmed:abstractText
At the end of the third larval instar of Drosophila, ecdysone triggers the tissue-specific activation of gene expression. In cytogenetic and molecular studies, the Broad-complex (BR-C) locus has been defined as a key element in the hierarchy of hormonal regulation of gene activity. Here we show that BR-C function is required for the regulation of the small hsp genes, which are clustered in the 67B puff and are known to be activated by heat shock and by ecdysone during development. We have found that the genes of the 67B cluster are expressed differentially in the salivary glands. While hsp23 and hsp27 transcripts accumulate at relatively high levels, those of hsp22 and hsp26 are present at low and intermediate levels, respectively. The complete BR-C deficiency as well as mutations of the npr class reduce the expression of genes hsp23 and hsp27 by 95 to 99%. The analysis of mutants representing two subfunctions of the BR-C-l(1)2Bab and l(1)2Bc, has shown that the latter is principally required for complete hsp induction. As sites of DNase I hypersensitivity in chromatin are believed to correspond to gene regulatory sequences, we have studied the changes of chromatin structure in the 67B region at different states of hsp gene activity. Upon hormonal induction, at the onset of metamorphosis, additional DNase I hypersensitive sites (DHS) appear in the 5' regions, four DHSs are associated with hsp23 and two with hsp27. We suggest that they are due to the binding of the hormone-receptor complex and/or transcription factors, related to ecdysone action. Finally, two DHSs (at -1400 of hsp23 and at -1200 of hsp27) are absent in the mutant nuclei, and thus may correspond to the target sequences for the BR-C-dependent regulatory protein(s).
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0022-2836
pubmed:author
pubmed:issnType
Print
pubmed:day
19
pubmed:volume
241
pubmed:geneSymbol
BR-C, hsp22, hsp23, hsp26, hsp27
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
353-62
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
The Drosophila broad-complex regulates developmental changes in transcription and chromatin structure of the 67B heat-shock gene cluster.
pubmed:affiliation
Laboratoire de Génétique Moléculaire du CNRS, Unité 184 de Biologie moléculaire, Institut de Chimie Biologique, Faculté de Médecine, Strasbourg, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't