title: Nocturnal behavior and rhythmic period gene expression in a lancelet, Branchiostoma lanceolatum.
abstract: The authors here present the first anatomical, molecular biological, and ethological data on the organization of the circadian system of a lancelet, Branchiostoma lanceolatum, a close invertebrate relative of vertebrates. B. lanceolatum was found to be a nocturnal animal and, since its rhythmic activity persisted under constant darkness, it also appears to possess an endogenous, circadian oscillator. The authors cloned a homolog of the clock gene Period (Per), which plays a central (inhibitory) role in the biochemical machinery of the circadian oscillators of both vertebrates and protostomians. This gene from B. lanceolatum was designated as amphiPer. Both the sequence of its cDNA and that of the predicted protein are more similar to those of the Per paralogs of vertebrates than to those of the single protostomian Per gene. A strong expression of amphiPer was found in a small cell group in the anterior neural tube. The amphiPer mRNA levels fluctuated in a rhythmic manner, being high early in the day and low late at night. The authors' data suggest a homology of the amphiPer expessing cells to the suprachiasmatic nucleus of vertebrates.
authors: Fachbereich Medizin der Johann Wolfgang Goethe-Universität, Dr. Senckenbergische Anatomie, Institut für Anatomie II, Frankfurt, Germany. Schomerus@em.uni-frankfurt.de
authors: Christof
authors: C
authors: Schomerus
authors: Horst-Werner
authors: HW
authors: Korf
authors: Elke
authors: E
authors: Laedtke
authors: Frédéric
authors: F
authors: Moret
authors: Qian
authors: Q
authors: Zhang
authors: Helmut
authors: H
authors: Wicht
mesh_terms: D000818:Animals; D001519:Behavior / Q000502:physiology*; D001683:Biological Clocks / Q000502:physiology*; D002816:Chordata, Nonvertebrate / Q000502:physiology*; D002940:Circadian Rhythm / Q000502:physiology*; D003624:Darkness; D005260:Female; D005786:Gene Expression Regulation; D008297:Male; D009687:Nuclear Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D017440:Photoperiod; D010802:Phylogeny
chemical_list: D009687:Nuclear Proteins