Event

Abstract: Sleep is nearly ubiquitous throughout the animal kingdom, yet its duration and timing varies dramatically between species. We have developed the Mexican tetra, Astyanax mexicanus as a model to study evolved changes in sleep, and how naturally occurring genetic variation encodes for sleep differences between individuals. These fish exist as eyed-surface populations that inhabit the rivers of northeast Mexico and multiple blind cave populations that have converged on sleep loss. We have identified neuromodulators that contribute to the evolution of sleep loss in A. mexicanus cavefish including upregulation of the wake-promoting neuropeptide Hypocretin/Orexin. In addition, we have developed transgenic and gene-editing methodology in this emergent model system allowing for systematic investigation of the genes and neurons regulating evolved differences in sleep. Systematic analysis has identified convergence on wide-spread neuroanatomical differences between surface fish and cavefish including hypothalamic expansion that is accompanied by increased sleep intensity. Current studies seek to identify how naturally occurring genetic variation contributes do these phenotypes. Investigating the mechanisms of sleep loss in Mexican cavefish has potential to provide insights into the variation in sleep need throughout the animal kingdom. Further, the resources developed to study sleep can be broadly applied to study other cavefish associated traits including obesity, diabetes, and dysregulation of stress response.

Twitter: @AlexCarlKeene