Abstract:
:TEL1 is important in Saccharomyces cerevisiae telomere maintenance, and its kinase activity is required. Tel1p associates with telomeres in vivo, is enriched at short telomeres, and enhances the binding of telomerase components to short telomeres. However, it is unclear how the kinase activity and telomere association contribute to Tel1p's overall function in telomere length maintenance. To investigate this question, we generated a set of single point mutants and a double point mutant (tel1(KD)) of Tel1p that were kinase deficient and two Xrs2p mutants that failed to bind Tel1p. Using these separation-of-function alleles in a de novo telomere elongation assay, we found, surprisingly, that the tel1(KD) allele and xrs2 C-terminal mutants were both partially functional. Combining the tel1(KD) and xrs2 C-terminal mutants had an additive effect and resembled the TEL1 null (tel1Delta) phenotype. These data indicate that Tel1p has two separate functions in telomere maintenance and that the Xrs2p-dependent recruitment of Tel1p to telomeres plays an important role even in the absence of its kinase activity.
journal_name
Mol Cell Bioljournal_title
Molecular and cellular biologyauthors
Ma Y,Greider CWdoi
10.1128/MCB.01896-08subject
Has Abstractpub_date
2009-09-01 00:00:00pages
5193-202issue
18eissn
0270-7306issn
1098-5549pii
MCB.01896-08journal_volume
29pub_type
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pub_type: 杂志文章
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