Release of telomeric DNA from chromosomes in immortal human cells lacking telomerase activity

Biochem Biophys Res Commun. 1998 Jul 20;248(2):223-7. doi: 10.1006/bbrc.1998.8875.


Some immortal human cell lines lack telomerase activity. These cell lines were found to contain small dispersed DNA hybridizing to TTAGGG repeats. Such DNA was located in their cytoplasm and nuclei. Normal human fibroblasts or telomerase-positive cell lines did not contain such DNA. Upon cloning and sequencing, it was shown to consist of TTAGGG repeats. When electrophoresed on neutral and alkaline agarose gels, it behaved as double-stranded and linear DNA. These results suggest that telomeric DNA is released from chromosomes in association with maintenance of telomeres in telomerase-negative cell lines.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line
  • Chromosomes / genetics*
  • Cloning, Molecular
  • DNA / chemistry*
  • DNA, Circular / genetics
  • Electrophoresis, Agar Gel
  • Humans
  • Nucleic Acid Conformation
  • Nucleic Acid Hybridization
  • Repetitive Sequences, Nucleic Acid / genetics
  • Sequence Analysis, DNA
  • Telomere / genetics*


  • DNA, Circular
  • DNA