Analysis of Thermosensitive Neurons Required for Temperature-entrained Rhythms of C. elegans

Abstract

Circadian clocks function to synchronize the organismal biology, including behavior and gene expression, to a 24 hour cycle following the Earth’s axial rotation. The circadian clock is most commonly entrained via light, however in organisms who are rarely exposed to light, temperature provides another important external cue. Although light-entrainment has been heavily studied in higher organisms such as Drosophila melanogaster and mammals, little is known how temperature entrains the circadian clock. Previous research in the lab has discovered circadian genes entrained by temperature cycles in Caenorhabditis elegans (C.elegans), a free-living nematode that lives in soil and whose genome has been completely mapped. To further understand how temperature entrains the C. elegans circadian clock, a novel circadian reporter was developed in which temperature-entrained rhythms can be monitored. Since C. elegans has a well-mapped neural circuitry with defined thermosensitive neurons that sense small changes in temperatures, we combined the novel circadian reporter with strains in which the function of specific thermosensitive neurons were genetically ablated. The goal of this thesis is to identify the neural pathways underlying the temperatureentrained clock of C. elegans.