Meeting Abstract
Circadian clocks allow organisms to anticipate and respond to periodic fluctuations in their environment. In order to synchronize to local conditions, clocks must integrate information from multiple cues such as light and temperature. Nematostella vectensis, the starlet sea anemone, exhibits circadian locomotory behavior and gene expression both in the field and in response to artificial light-dark cycles. Clocks are known to robustly entrain to daily temperature cycles in crustaceans and insects as well as ectothermic vertebrates, and this ability also exists in non-metazoan eukaryotes. However, thermal entrainment has not been well-studied in cnidarians or other non-arthropod invertebrates. We have designed a system to control temperature and conduct behavioral assays, allowing us to answer whether cnidarians, which belong to an evolutionarily early-branching group of animals, also exhibit robust thermal entrainment under constant light conditions. In insects and vertebrates, light and temperature activate overlapping yet distinct molecular pathways, but the photosensitive and thermosensitive elements of the cnidarian clock have not been identified. Gene expression analysis over daily temperature cycles will identify candidate genes whose expression differs between these two sensory modalities. Dissecting the behavioral effects and molecular components of different sensory pathways in an early-diverging metazoan will allow us to better understand the evolution of the metazoan clock.
