title: Profiling molecular and behavioral circadian rhythms in the non-symbiotic sea anemone Nematostella vectensis.
abstract: Endogenous circadian clocks are poorly understood within early-diverging animal lineages. We have characterized circadian behavioral patterns and identified potential components of the circadian clock in the starlet sea anemone, Nematostella vectensis: a model cnidarian which lacks algal symbionts. Using automatic video tracking we showed that Nematostella exhibits rhythmic circadian locomotor activity, which is persistent in constant dark, shifted or disrupted by external dark/light cues and maintained the same rate at two different temperatures. This activity was inhibited by a casein kinase 1δ/ε inhibitor, suggesting a role for CK1 homologue(s) in Nematostella clock. Using high-throughput sequencing we profiled Nematostella transcriptomes over 48 hours under a light-dark cycle. We identified 180 Nematostella diurnally-oscillated transcripts and compared them with previously established databases of adult and larvae of the symbiotic coral Acropora millepora, revealing both shared homologues and unique rhythmic genes. Taken together, this study further establishes Nematostella as a non-symbiotic model organism to study circadian rhythms and increases our understanding about the fundamental elements of circadian regulation and their evolution within the Metazoa.
authors.affiliation: The Mina &Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel.
authors.forename: Matan
authors.initials: M
authors.lastname: Oren
authors.affiliation: Biology Department, Woods Hole Oceanographic Institution, Woods Hole MA 02543, USA.
authors.forename: Ann M
authors.initials: AM
authors.lastname: Tarrant
authors.affiliation: 1] George S. Wise Faculty of Life Sciences, Department of Neurobiology, Tel-Aviv University, Tel-Aviv 69978, Israel [2] Sagol School of Neuroscience, Tel-Aviv University, Tel-Aviv 69978, Israel.
authors.forename: Shahar
authors.initials: S
authors.lastname: Alon
authors.affiliation: The Mina &Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel.
authors.forename: Noa
authors.initials: N
authors.lastname: Simon-Blecher
authors.affiliation: 1] The Mina &Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel [2] The Leslie and Susan Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat-Gan, Israel.
authors.forename: Idan
authors.initials: I
authors.lastname: Elbaz
authors.affiliation: 1] The Mina &Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel [2] The Leslie and Susan Gonda Multidisciplinary Brain Research Center, Bar-Ilan University, Ramat-Gan, Israel.
authors.forename: Lior
authors.initials: L
authors.lastname: Appelbaum
authors.affiliation: The Mina &Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan 52900, Israel.
authors.forename: Oren
authors.initials: O
authors.lastname: Levy
mesh_terms: D000818:Animals; D037421:Anthozoa / Q000235:genetics; D057906:Circadian Clocks; D002940:Circadian Rhythm / Q000502:physiology*; D016000:Cluster Analysis; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D008124:Locomotion; D017440:Photoperiod; D012615:Sea Anemones / Q000502:physiology*; D059467:Transcriptome