Environmental stresses disrupt telomere length homeostasis

Area of Science:

• Molecular Biology
• Genetics
• Cellular Biology

Background:

• Telomeres protect chromosome ends and are linked to aging and disease.
• Previous studies suggest a correlation between psychological stress, telomere length, and human health outcomes.
• The causal relationship and molecular mechanisms linking stress and telomere length remain unexplored.

Purpose of the Study:

• To investigate the causal relationship between environmental stresses and telomere length.
• To identify the molecular mechanisms mediating the telomeric response to environmental signals.

Main Methods:

• Utilized yeast as a model organism for controlled experiments.
• Applied various environmental stresses including alcohol, acetic acid, caffeine, high temperatures, and oxidative stress.
• Combined genome-wide expression measurements with a systematic genetic screen.

Main Results:

• Demonstrated differential effects of stresses on telomere length: alcohol and acetic acid elongated telomeres, while caffeine and high temperatures shortened them.
• Identified the Rap1/Rif1 pathway as a central mediator of the telomeric response to environmental signals.
• Showed that oxidative stress had no significant effect on telomere length.

Conclusions:

• Telomere length is responsive to environmental cues and can be manipulated.
• The Rap1/Rif1 pathway plays a critical role in mediating telomere length regulation.
• Environmental signals can lead to deregulation of telomere homeostasis in opposing directions.