Meeting Abstract
Telomeres, the repetitive DNA sequence at the end of chromosomes, are essential to maintain genome stability. It is known that telomeres shorten with age, but recent evidence indicates that, in humans, social stress may also shorten telomeres due to increased oxidative stress associated with high cortisol levels. Telomerase, the enzyme that repairs and lengthens telomeres, shows decreased activity in response to oxidative stress and reduced activity in chronically stressed humans. The teleost fish Astatotilapia burtoni presents an exquisite model for this field of research. Like other fish, they exhibit a high level of telomerase activity throughout life in many tissues and individuals experience different levels of social stress dependent on the dominance hierarchy. We tested the hypothesis that social stress in the form of a dominance hierarchy is correlated with telomerase activity. Analysis of telomerase activity with the TRAP assay revealed that subordinate fish, who are known to have higher levels of the stress hormone cortisol, had lower levels of telomerase activity than their dominant, less-stressed, dominant conspecifics. This study demonstrates that stressed A. burtoni also have repressed telomerase activity, the same pattern seen in humans, thus validating the use of these organisms for studying telomere and telomerase dynamics.
