Telomerase and Tel1p preferentially associate with short telomeres in S. cerevisiae.
Mol Cell
; 27(4): 550-61, 2007 Aug 17.
Article
em En
| MEDLINE
| ID: mdl-17656141
ABSTRACT
In diverse organisms, telomerase preferentially elongates short telomeres. We generated a single short telomere in otherwise wild-type (WT) S. cerevisiae cells. The binding of the positive regulators Ku and Cdc13p was similar at short and WT-length telomeres. The negative regulators Rif1p and Rif2p were present at the short telomere, although Rif2p levels were reduced. Two telomerase holoenzyme components, Est1p and Est2p, were preferentially enriched at short telomeres in late S/G2 phase, the time of telomerase action. Tel1p, the yeast ATM-like checkpoint kinase, was highly enriched at short telomeres from early S through G2 phase and even into the next cell cycle. Nonetheless, induction of a single short telomere did not elicit a cell-cycle arrest. Tel1p binding was dependent on Xrs2p and required for preferential binding of telomerase to short telomeres. These data suggest that Tel1p targets telomerase to the DNA ends most in need of extension.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Saccharomyces cerevisiae
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Cromossomos Fúngicos
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Telômero
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Proteínas Serina-Treonina Quinases
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Telomerase
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Proteínas de Saccharomyces cerevisiae
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Peptídeos e Proteínas de Sinalização Intracelular
Tipo de estudo:
Risk_factors_studies
Idioma:
En
Revista:
Mol Cell
Ano de publicação:
2007
Tipo de documento:
Article