Meeting Abstract

S7-1.2  Sunday, Jan. 6  Circadian clock of the starlet sea anemone Nematostella vectensis: a conserved network and missing links REITZEL, A.M.*; TARRANT, A.M.; Univ. of North Carolina, Charlotte; Woods Hole Oceanographic Inst. areitzel@whoi.edu

The molecular components of the circadian clocks of mammals and diverse insects have been well-characterized, revealing that many of the core clock genes are conserved in these two disparate animal groups. This deep conservation suggests that this molecular clock dates back to at least the ancestor of deuterostomes and protostomes (Bilateria). The origin of these clock components and their molecular interactions earlier in animal evolution is unknown but represents a tremendous opportunity for studying the emergence of deeply conserved gene networks in animal behavior and physiology. Comparative genomic analyses support a hypothesis that the genes composing the circadian clock defined in bilaterians arose just prior to the cnidarian-bilaterian ancestor. Recent studies, using reef-building corals, and especially the sea anemone Nematostella vectensis, have provided considerable insight into circadian regulation within cnidarians. Several lines of evidence that we will present, including computational biology, gene expression profiling, co-immunoprecipitation, and reporter assays, suggest that the cnidarian clock shares many conserved components of the circadian clock with bilaterians. Investigation into conserved and novel mechanisms of the circadian clocks from cnidarians and other early-diverging animal groups will elucidate the antiquity of this gene regulatory network and provide insight into regulation of reproduction, physiology, and development – processes that are frequently correlated with daily oscillations in environmental cues.