Source:http://linkedlifedata.com/resource/pubmed/id/10514435
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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
42
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pubmed:dateCreated |
1999-11-19
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pubmed:abstractText |
Metallothioneins are small, cysteine-rich proteins that function in metal detoxification and homeostasis. Metallothionein transcription is controlled by cell-specific factors, as well as developmentally modulated and metal-responsive pathways. By using the nematode Caenorhabditis elegans as a model system, the mechanism that controls cell-specific metallothionein transcription in vivo was investigated. The inducible expression of the C. elegans metallothionein genes, mtl-1 and mtl-2, occurs exclusively in intestinal cells. Sequence comparisons of these genes with other C. elegans intestinal cell-specific genes identified multiple repeats of GATA transcription factor-binding sites (i.e. GATA elements). In vivo deletion and site-directed mutation analyses confirm that one GATA element in mtl-1 and two in mtl-2 are required for transcription. Electrophoretic mobility shift assays show that the C. elegans GATA transcription factor ELT-2 specifically binds to these elements. Ectopic expression of ELT-2 in non-intestinal cells of C. elegans activates mtl-2 transcription in these cells. Likewise, mtl-2 is not expressed in nematodes in which elt-2 has been disrupted. These results indicate that cell-specific transcription of the C. elegans metallothionein genes is regulated by the binding of ELT-2 to GATA elements in these promoters. Furthermore, a model is proposed where ELT-2 constitutively activates metallothionein expression; however, a second metal-responsive factor prevents transcription in the absence of metals.
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pubmed:grant | |
pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical | |
pubmed:status |
MEDLINE
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pubmed:month |
Oct
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pubmed:issn |
0021-9258
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
15
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pubmed:volume |
274
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
29655-65
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pubmed:dateRevised |
2008-11-21
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pubmed:meshHeading |
pubmed-meshheading:10514435-Animals,
pubmed-meshheading:10514435-Base Sequence,
pubmed-meshheading:10514435-Caenorhabditis elegans,
pubmed-meshheading:10514435-DNA Primers,
pubmed-meshheading:10514435-Gene Expression Regulation,
pubmed-meshheading:10514435-Metallothionein,
pubmed-meshheading:10514435-Promoter Regions, Genetic,
pubmed-meshheading:10514435-Regulatory Sequences, Nucleic Acid,
pubmed-meshheading:10514435-Sequence Deletion,
pubmed-meshheading:10514435-Transcription, Genetic,
pubmed-meshheading:10514435-Transcription Factors
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pubmed:year |
1999
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pubmed:articleTitle |
Regulation of metallothionein gene transcription. Identification of upstream regulatory elements and transcription factors responsible for cell-specific expression of the metallothionein genes from Caenorhabditis elegans.
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pubmed:affiliation |
Nicholas School of the Environment, Duke University, Durham, North Carolina 27708, USA.
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pubmed:publicationType |
Journal Article,
Research Support, U.S. Gov't, P.H.S.,
Research Support, Non-U.S. Gov't
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