Fine-tuning the chromosome ends: The last base of human telomeres

Agnel J. Sfeir, Jerry W. Shay, Woodring E. Wright

Research output: Contribution to journalReview articlepeer-review

12 Scopus citations


Telomeres protect chromosomes from degradation and loss of vital sequence, block end-end fusion, and allow the cell to distinguish between broken ends and chromosome ends. Mammalian telomeres end in single-stranded (TTAGGG)-rich 3′-overhangs that are tucked back into the preceding double stranded region to form a T-loop. The end structure of mammalian telomeres has just started to be elucidated and through this extra views we highlight one aspect of that structure. We have recently identified the terminal nucleotides of both the C-rich and G-rich telomere strands in human cells and showed that ∼80% of the C-rich strands terminate precisely in ATC-5′, while the last base of the G-strand is less precise. This finding has important implications for the processing events that act on the telomere ends post-replication. While the mechanism behind this phenotype is yet to be unraveled, we discuss potential models that could explain the last base specificity.

Original languageEnglish (US)
Pages (from-to)1467-1470
Number of pages4
JournalCell Cycle
Issue number11
StatePublished - Nov 2005


  • End-replication problem
  • Pot1
  • Telomere
  • Terminal nucleotide

ASJC Scopus subject areas

  • Molecular Biology
  • Developmental Biology
  • Cell Biology


Dive into the research topics of 'Fine-tuning the chromosome ends: The last base of human telomeres'. Together they form a unique fingerprint.

Cite this