title: Gravity and light effects on the circadian clock of a desert beetle, Trigonoscelis gigas.
abstract: Circadian function is affected by exposure to altered ambient force environments. Under non-earth gravitational fields, both basic features of circadian rhythms and the expression of the clock responsible for these rhythms are altered. We examined the activity rhythm of the tenebrionid beetle, Trigonoscelis gigas, in conditions of microgravity (microG; spaceflight), earth's gravity (1 G) and 2 G (centrifugation). Data were recorded under a light-dark cycle (LD), constant light (LL), and constant darkness (DD). Free-running period (tau) was significantly affected by both the gravitational field and ambient light intensity. In DD, tau was longer under 2 G than under either 1 G or microG. In addition, tauLL was significantly different from tauDD under microG and 1 G, but not under 2 G.
authors.affiliation: University of California, Section of Neurobiology, Physiology and Behavior, One Shields Avenue, Davis, CA 95616, USA. tmhoban@ucdavis.edu
authors.forename: T M
authors.initials: TM
authors.lastname: Hoban-Higgins
authors.forename: A M
authors.initials: AM
authors.lastname: Alpatov
authors.forename: G T
authors.initials: GT
authors.lastname: Wassmer
authors.forename: W J
authors.initials: WJ
authors.lastname: Rietveld
authors.forename: C A
authors.initials: CA
authors.lastname: Fuller
mesh_terms: D000818:Animals; D001683:Biological Clocks / Q000502:physiology*; D002498:Centrifugation; D002940:Circadian Rhythm / Q000502:physiology*; D001517:Coleoptera / Q000502:physiology*; D006112:Gravitation; D008027:Light; D017440:Photoperiod; D013026:Space Flight; D014893:Weightlessness