Chromosome Research

, Volume 10, Issue 1, pp 21–31 | Cite as

Chromosome Ends in Chironomus Tentans Do Not Have Long Single-Stranded Overhangs Characterizing Canonical Telomeres

  • Monika Rosén
  • Jan-Erik Edström


Single-stranded overhangs of the G-rich strand belong to the conserved features of telomeres composed of short telomeric repeats. These structures are thought to be essential for the maintenance of proper telomeric structure and function and the mechanism of their generation is telomerase-independent. We have examined the presence of single-stranded overhangs in Chironomus tentans, a dipteran insect lacking canonical telomeres that uses 350-bp repeats to terminate its chromosomes. Using a non-denaturing in-gel hybridization technique, we found that C. tentans telomeres are unlikely to have single-stranded overhangs longer than 30 nt found in most other higher eukaryotes. These differences might reflect special capping mechanisms for telomeres terminated with long complex repeats.

Chironomus tentans 3′-overhangs repetitive DNA single strand protrusions telomere 


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Copyright information

© Kluwer Academic Publishers 2002

Authors and Affiliations

  • Monika Rosén
    • 1
  • Jan-Erik Edström
    • 2
  1. 1.Department of GeneticsLund UniversityLundSweden
  2. 2.Karolinska InstituteCMB, Medical Nobel InstituteStockholmSweden

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