Effects of UV-B radiation on whole-body gene expression of surface and cave Astyanax mexicanus
Dysregulation of sleep has widespread health consequences and represents an enormous health burden. Short-sleeping individuals are predisposed to the effects of neurodegeneration, suggesting a critical role for sleep in the maintenance of neuronal health. While the effects of sleep on cellular function are not completely understood, growing evidence has identified an association between sleep loss and DNA damage, raising the possibility that sleep facilitates efficient DNA repair. The Mexican tetra fish, Astyanax mexicanus provides a model to investigate the evolutionary basis for changes in sleep and the consequences of sleep loss. Multiple cave-adapted populations of these fish have evolved to sleep for substantially less time compared to surface populations of the same species without identifiable impacts on healthspan or longevity. To investigate whether the evolved sleep loss is associated with DNA damage and cellular stress, we compared the DNA Damage Response (DDR) between A. mexicanus populations. Overall design: To investigate differences in the DNA damage response, we subjected surface and cave larvae, at 6 days post-fertilization, to 60 seconds of UV-B radiation, or 60 seconds of white light as control. We then pooled individuals in groups of 4, extracted the RNA from each pooled sample, and performed gene expression analysis.