Clocks in Algae

As major contributors to global oxygen levels and producers of fatty acids, carotenoid, sterols and phycocolloids, algae have significant ecological and commercial roles. Early algal models have contributed much to our understanding of circadian clocks at physiological and biochemical levels. The genetic and molecular approaches that identified clock components in other taxa were not as widely applied to algae. We review results from seven species; the chlorophytes Chlamydomonas reinhardtii, Ostreococcus tauri, and Acetabularia spp.; the dinoflagellates Lingulodinium polyedrum and Symbiodinium spp.; the euglenozoa Euglena gracilis and the red alga Cyanidioschyzon merolae. The relative simplicity, experimental tractability, ecological and evolutionary diversity of algal systems may now make them particularly useful in integrating quantitative data from "omic" technologies (e.g. genomics, transcriptomics, metabolomics and proteomics) with computational and mathematical methods.