Cell cycle-dependent regulation of yeast telomerase by Ku
Cell cycle-dependent regulation of yeast telomerase by Ku
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DOI：
10.1038/nsmb854
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发表时间：
2004-12-01
影响因子：
16.8
通讯作者：
Zakian, VA
中科院分区：
文献类型：
--
作者：
Fisher, TS;Taggart, AKP;Zakian, VA
异二聚体Ku复合体影响不同生物的端粒结构。在此，我们报道了在没有Ku的情况下，端粒酶催化亚基Est2p在G1期不与端粒相关，而在S晚期端粒结合减少。Est1p是一种仅在S晚期结合端粒的端粒酶成分，在没有Ku的情况下，端粒的结合也降低了。Ku对端粒酶结合的影响需要TLC1端粒酶RNA的48个核苷酸(NT)茎环区。在整个细胞周期中，Ku通过这个48个核苷酸的区域与TLC1 RNA相互作用，但这种相互作用在端粒复制后被减少。这些数据支持这样一种模型，即当端粒酶不活跃时，Ku将端粒酶招募到G1期的端粒中，并在S晚期促进端粒酶介导的端粒延长。
The heterodimeric Ku complex affects telomere structure in diverse organisms. We report here that in the absence of Ku, the catalytic subunit of telomerase, Est2p, was not telomere-associated in G1 phase, and its association in late S phase was decreased. The telomere association of Est1p, a telomerase component that binds telomeres only in late S phase, was also reduced in the absence of Ku. The effects of Ku on telomerase binding require a 48-nucleotide (nt) stem-loop region of TLC1 telomerase RNA. Ku interacts with TLC1 RNA via this 48-nt region throughout the cell cycle, but this interaction was reduced after telomere replication. These data support a model in which Ku recruits telomerase to telomeres in G1 phase when telomerase is inactive and promotes telomerase-mediated telomere lengthening in late S phase.