Human cancer cells harbor T-stumps, a distinct class of extremely short telomeres.
Human cancer cells harbor T-stumps, a distinct class of extremely short telomeres.
复制标题
DOI：
10.1016/j.molcel.2007.10.005
复制
发表时间：
2007-10
期刊：
影响因子：
16
通讯作者：
Lifeng Xu;E. Blackburn
中科院分区：
文献类型：
--
作者：
Lifeng Xu;E. Blackburn
Using a modified single telomere length analysis protocol (STELA) to clone and examine the sequence composition of individual human XpYp telomeres, we discovered a distinct class of extremely short telomeres in human cancer cells with active telomerase. We name them "t-stumps," to distinguish them from the well-regulated longer bulk telomeres. T-stumps contained arrangements of telomeric repeat variants and a minimal run of seven canonical telomeric TTAGGG repeats, but all could bind at least one TRF1 or TRF2 in vitro. The abundance of t-stumps was unaffected by ATM alteration but could be changed by manipulating telomerase catalytic subunit (hTERT) levels in cancer cells. We propose that in the setting of active telomerase and compromised checkpoints characteristic of human cancer cells, t-stumps define the minimal telomeric unit that can still be protected by a TRF1/TRF2-capping complex and, further, that hTERT (or telomerase) may have a role in protecting t-stumps.
