Related Experiment Video
Updated: Sep 15, 2025
12:08
Telomere Length and Telomerase Activity; A Yin and Yang of Cell Senescence
Published on: May 22, 2013
46.7K
A Chromosome End Without Terminal Telomere Repeats is Stable for Multiple Cell Divisions
Haitao Zhang1, Julien Audry1,2, Kurt W Runge1,3
1Department of Inflammation and Immunity, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, Ohio, 44195 USA.
Biorxiv : the Preprint Server for Biology
|July 14, 2025
Summary
New research shows that fission yeast cells can divide multiple times with shortened telomeres, challenging existing models of telomere protection and replication. This study investigates telomere maintenance in Schizosaccharomyces pombe lacking telomerase activity.
Area of Science:
- Cell biology
- Genetics
- Molecular biology
Background:
- Telomeres protect chromosome ends from degradation and fusion.
- Telomere length is maintained by the enzyme telomerase.
- The precise mechanisms of telomere protection and replication are not fully understood.
Purpose of the Study:
- To investigate telomere maintenance in Schizosaccharomyces pombe under conditions of impaired telomerase function.
- To challenge current models of telomere protection and replication.
Main Methods:
- Inducible nuclease used to create short telomeres in Schizosaccharomyces pombe.
- Telomere sequencing to analyze chromosome ends.
- Cell division tracking in cells with impaired telomerase.
Main Results:
- Cells lacking telomerase divided at least 4 times with ~30 bp of non-telomeric sequence at chromosome ends.
- This observation contradicts current models of telomere protection.
- Cells with impaired telomerase recruitment or activation showed rearrangements or telomere repeat addition.
Conclusions:
- Short telomeres with non-telomeric sequences can be tolerated in Schizosaccharomyces pombe.
- Telomere protection and replication models require revision.
- Telomere length regulation is more flexible than previously thought.
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