Demystifying broadcast coral spawning in Acropora digitifera. Acropora digitifera

Natural light cycles are important for synchronizing behavioral and physiological rhythms over varying time-periods in both plants and animals. An endogenous clock, regulated by positive and negative molecular mechanisms, interacting in feedback loops, controls these rhythms. Many corals exhibit diel cycles of polyp expansion and contraction entrained by solar light patterns and monthly cycles of spawning or planulation that correspond to nocturnal lunar light cycles. However, despite considerable interest in studies of coral reproduction in different species from a wide range of geographical locations, there is currently not enough molecular information about the cellular pathways concerned with synchronizing spawning/planulation in broadcast spawners and brooders.To determine whether the molecular clock is implicated in the regulation of reproductive behavior in corals, we characterized the transcriptome of Acropora digitifera colonies at twelve time points over a two-month period of full and new moons, starting with the day of spawning in June 2014.