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Updated: May 10, 2026
09:13
Generation of Cancer Cell Clones to Visualize Telomeric Repeat-containing RNA TERRA Expressed from a Single Telomere in Living Cells
Published on: January 17, 2019
Inter-telomeric recombination is present in telomerase-positive human cells
Margit Dlaska1, Patrick Schöffski, Oliver E Bechter
1Department for Internal Medicine I, University Hospital Innsbruck, Innsbruck, Austria.
Cell Cycle (Georgetown, Tex.)
|June 14, 2013
Summary
Homologous recombination occurs in both telomerase and alternative lengthening of telomeres (ALT) pathways for cell division. However, factors influencing this recombination differ between telomere maintenance mechanisms.
Area of Science:
- Cell Biology
- Genetics
- Molecular Biology
Background:
- Immortal cells require telomere length maintenance for infinite division.
- Telomere length is controlled by telomerase or the alternative lengthening of telomeres (ALT) pathway.
- ALT pathway cells utilize homologous recombination for telomere homeostasis.
Purpose of the Study:
- To investigate the presence and frequency of inter-telomeric homologous recombination in telomerase-positive cells.
- To compare inter-telomeric recombination between telomerase and ALT pathways.
- To identify factors that modulate inter-telomeric recombination in different telomere maintenance pathways.
Main Methods:
- Development of a novel, sensitive homologous recombination reporter system.
- Measurement of inter-telomeric recombination frequency in vitro.
- Induction of telomere shortening and fragile telomeres using aphidicolin.
Main Results:
- Inter-telomeric homologous recombination is detectable in both ALT and telomerase-positive cells at similar frequencies.
- A specific ALT cell clone exhibited unique recombination peaks not seen in telomerase-positive cells.
- Shortened telomeres or aphidicolin did not increase recombination in telomerase-positive cells.
- Aphidicolin treatment increased recombination frequency in ALT cells.
Conclusions:
- Inter-telomeric homologous recombination is a feature of both telomere maintenance pathways.
- The stimuli that enhance recombination differ significantly between the telomerase and ALT pathways.
- This study provides new insights into the distinct regulatory mechanisms of telomere recombination.
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