Related Experiment Video
Updated: Aug 7, 2025
12:08
Telomere Length and Telomerase Activity; A Yin and Yang of Cell Senescence
Published on: May 22, 2013
46.6K
TERT Extra-Telomeric Roles: Antioxidant Activity and Mitochondrial Protection
Jessica Marinaccio1, Emanuela Micheli1, Ion Udroiu1
1Department of Science, University "ROMA TRE", 00146 Rome, Italy.
International Journal of Molecular Sciences
|March 11, 2023
Summary
Telomerase reverse transcriptase (TERT) protects cells from oxidative stress by reducing reactive oxygen species and enhancing antioxidant defenses. TERT also localizes to mitochondria, preserving their function under stress.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Telomerase reverse transcriptase (TERT) is crucial for maintaining telomere length.
- Emerging evidence suggests TERT possesses non-canonical functions, including antioxidant properties.
- Understanding these roles is vital for cellular health and disease research.
Purpose of the Study:
- To investigate the antioxidant role of TERT in human fibroblasts.
- To determine TERT's response to oxidative stress induced by X-rays and H2O2.
- To explore TERT's localization and function within mitochondria.
Main Methods:
- Overexpression of hTERT in human fibroblasts (HF-TERT).
- Exposure to X-ray and H2O2 to induce oxidative stress.
- Measurement of reactive oxygen species (ROS) levels and antioxidant protein expression.
- Assessment of TERT mitochondrial localization and mitochondrial markers (quantity, membrane potential, morphology).
Main Results:
- HF-TERT cells showed reduced ROS induction and increased antioxidant protein expression.
- TERT was confirmed to localize in mitochondria, with increased presence after H2O2 treatment.
- Mitochondrial quantity decreased in HF-TERT cells, but membrane potential and morphology were better preserved under oxidative stress.
Conclusions:
- TERT exhibits a protective function against oxidative stress.
- TERT contributes to maintaining mitochondrial functionality during oxidative challenges.
- TERT's non-canonical antioxidant role, including mitochondrial localization, is significant for cellular protection.
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