Ku interacts with telomerase RNA to promote telomere addition at native and broken chromosome ends

被引:232
作者
Stellwagen, AE [1 ]
Haimberger, ZW [1 ]
Veatch, JR [1 ]
Gottschling, DE [1 ]
机构
[1] Fred Hutchinson Canc Res Ctr, Seattle, WA 98109 USA
关键词
telomerase; Ku; telomere; DNA repair; Saccharomyces cerevisiae; RNA-protein interaction;
D O I
10.1101/gad.1125903
中图分类号
Q2 [细胞生物学];
学科分类号
071009 ; 090102 ;
摘要
Ku is a conserved DNA end-binding protein that plays various roles at different kinds of DNA ends. At telomeres, Ku is part of the structure that protects the chromosome end, whereas at broken DNA ends, Ku promotes DNA repair as part of the nonhomologous end-joining (NHEJ) pathway. Here, we present evidence of a new role for Ku that impacts both telomere-length maintenance and DNA repair in Saccharomyces cerevisiae. We show that Ku binds TLC1, the RNA component of telomerase. We also describe a novel separation-of-function allele of Ku that is specifically defective in TLC1 binding. In this mutant, telomeres are short and the kinetics of telomere addition are slow, but other Ku-dependent activities, such as chromosome end protection and NHEJ, are unaffected. At low frequency, yeast will use telomerase to heal DNA damage by capping the broken chromosome with telomeric DNA sequences. We show that when Ku's ability to bind TLC1 is disrupted, DNA repair via telomere healing is reduced 10- to 100-fold, and the spectrum of sequences that can acquire a telomere changes. Thus, the interaction between Ku and TLC1 RNA enables telomerase to act at both broken and normal chromosome ends.
引用
收藏
页码:2384 / 2395
页数:12
相关论文
共 54 条
[41]   SILENT DOMAINS ARE ASSEMBLED CONTINUOUSLY FROM THE TELOMERE AND ARE DEFINED BY PROMOTER DISTANCE AND STRENGTH, AND BY SIR3 DOSAGE [J].
RENAULD, H ;
APARICIO, OM ;
ZIERATH, PD ;
BILLINGTON, BL ;
CHHABLANI, SK ;
GOTTSCHLING, DE .
GENES & DEVELOPMENT, 1993, 7 (7A) :1133-1145
[42]   A generic protein purification method for protein complex characterization and proteome exploration [J].
Rigaut, G ;
Shevchenko, A ;
Rutz, B ;
Wilm, M ;
Mann, M ;
Séraphin, B .
NATURE BIOTECHNOLOGY, 1999, 17 (10) :1030-1032
[43]   Ku is required for telomeric C-rich strand maintenance but not for end-to-end chromosome fusions in Arabidopsis [J].
Riha, K ;
Shippen, DE .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 2003, 100 (02) :611-615
[44]   Mammalian Ku86 protein prevents telomeric fusions independently of the length of TTAGGG repeats and the G-strand overhang [J].
Samper, E ;
Goytisolo, FA ;
Slijepcevic, P ;
van Buul, PPW ;
Blasco, MA .
EMBO REPORTS, 2000, 1 (03) :244-252
[45]   HTERT associates with human telomeres and enhances genomic stability and DNA repair [J].
Sharma, GG ;
Gupta, A ;
Wang, H ;
Scherthan, H ;
Dhar, S ;
Gandhi, V ;
Iliakis, G ;
Shay, JW ;
Young, CSH ;
Pandita, TK .
ONCOGENE, 2003, 22 (01) :131-146
[46]  
Singer MS, 1998, GENETICS, V150, P613
[47]  
SINGH D, 1994, INDIAN J CHEM TECHN, V1, P266
[48]   Association of the Est1 protein with telomerase activity in yeast [J].
Steiner, BR ;
Hidaka, K ;
Futcher, B .
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA, 1996, 93 (07) :2817-2821
[49]   Telomerase subunit overexpression suppresses telomere-specific checkpoint activation in the yeast yku80 mutant [J].
Teo, SH ;
Jackson, SP .
EMBO REPORTS, 2001, 2 (03) :197-202
[50]   Ku autoantigen: A multifunctional DNA-binding protein [J].
Tuteja, R ;
Tuteja, N .
CRITICAL REVIEWS IN BIOCHEMISTRY AND MOLECULAR BIOLOGY, 2000, 35 (01) :1-33