Send to

Choose Destination
Nat Struct Mol Biol. 2011 Apr;18(4):451-6. doi: 10.1038/nsmb.2034. Epub 2011 Mar 27.

Long telomeres are preferentially extended during recombination-mediated telomere maintenance.

Author information

Department of Genetics and Development, Columbia University Medical Center, New York, New York, USA.


Most human somatic cells do not express telomerase. Consequently, with each cell division their telomeres progressively shorten until replicative senescence is induced. Around 15% of human cancers maintain their telomeres using telomerase-independent, recombination-based mechanisms that are collectively termed 'alternative lengthening of telomeres' (ALT). In the yeast Saccharomyces cerevisiae, ALT cells are referred to as 'survivors'. One type of survivor (type II) resembles human ALT cells in that both are defined by the amplification of telomeric repeats. We analyzed recombination-mediated telomere extension events at individual telomeres in telomerase-negative yeast during the formation of type II survivors and found that long telomeres were preferentially extended. Furthermore, senescent cells with long telomeres were more efficient at bypassing senescence by the type II pathway. We speculate that telomere length may be important in determining whether cancer cells use telomerase or ALT to bypass replicative senescence.

[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Nature Publishing Group Icon for PubMed Central
Loading ...
Support Center