Source:http://linkedlifedata.com/resource/pubmed/id/11919561
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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
3
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pubmed:dateCreated |
2002-3-28
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pubmed:abstractText |
Telomeres in most immortal cells are maintained by the enzyme telomerase, allowing cells to divide indefinitely. Some telomerase-negative tumors and immortal cell lines maintain long heterogeneous telomeres by the ALT (alternative lengthening of telomeres) mechanism; such tumors are expected to be resistant to anti-telomerase drug therapies. Occasionally telomerase-negative Saccharomyces cerevisiae mutants survive, and 10% of them (type II survivors) have unstable telomeres. As in human ALT+ cells, short telomeres in yeast type II survivors lengthen abruptly; in yeast, this is dependent on the recombination proteins Rad52p and Rad50p. In human cells, ALT involves copying of sequence from a donor to a recipient telomere. We have characterized for the first time a class of complex telomere mutations seen only in ALT+ cells. The mutant telomeres are defined by the replacement of the progenitor telomere at a discrete point (fusion point) with a different telomere repeat array. Among 19 characterized fusion points, one occurred within the first six repeats of the telomere, indicating that these recombination-like events can occur anywhere within the telomere. One mutant telomere may have been involved in a secondary recombination-like mutation event, suggesting that these mutations are sporadic but ongoing in ALT+ cells. We also identified simple intra-allelic mutations at high frequency, which evidently contribute to telomere instability in ALT+ cells.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:status |
MEDLINE
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pubmed:month |
Mar
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pubmed:issn |
1061-4036
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:volume |
30
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
301-5
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pubmed:dateRevised |
2006-11-15
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pubmed:meshHeading | |
pubmed:year |
2002
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pubmed:articleTitle |
Molecular characterization of inter-telomere and intra-telomere mutations in human ALT cells.
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pubmed:affiliation |
Department of Genetics, University of Leicester, University Road, Leicester, LE1 7RH, UK.
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pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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