title: Day-night cycles and the sleep-promoting factor, Sleepless, affect stem cell activity in the Drosophila testis.
abstract: Adult stem cells maintain tissue integrity and function by renewing cellular content of the organism through regulated mitotic divisions. Previous studies showed that stem cell activity is affected by local, systemic, and environmental cues. Here, we explore a role of environmental day-night cycles in modulating cell cycle progression in populations of adult stem cells. Using a classic stem cell system, the Drosophila spermatogonial stem cell niche, we reveal daily rhythms in division frequencies of germ-line and somatic stem cells that act cooperatively to produce male gametes. We also examine whether behavioral sleep-wake cycles, which are driven by the environmental day-night cycles, regulate stem cell function. We find that flies lacking the sleep-promoting factor Sleepless, which maintains normal sleep in Drosophila, have increased germ-line stem cell (GSC) division rates, and this effect is mediated, in part, through a GABAergic signaling pathway. We suggest that alterations in sleep can influence the daily dynamics of GSC divisions.
authors: Cancer Biology Program, Fox Chase Cancer Center, Temple University School of Medicine, Philadelphia, PA 19111-2497.
authors: Natalia M
authors: NM
authors: Tulina
authors: Wen-Feng
authors: WF
authors: Chen
authors: Jung Hsuan
authors: JH
authors: Chen
authors: Mallory
authors: M
authors: Sowcik
authors: Amita
authors: A
authors: Sehgal
mesh_terms: D053687:Adult Stem Cells / Q000502:physiology*; D000818:Animals; D001973:Bromodeoxyuridine; D002940:Circadian Rhythm / Q000502:physiology*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D004330:Drosophila / Q000502:physiology*; D029721:Drosophila Proteins / Q000378:metabolism*; D059330:GABAergic Neurons / Q000378:metabolism; D005854:Germ Cells / Q000502:physiology; D006706:Homeostasis / Q000502:physiology; D007539:Isonicotinic Acids; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism*; D015735:Mifepristone; D015398:Signal Transduction / Q000502:physiology; D012890:Sleep / Q000502:physiology*; D013737:Testis / Q000166:cytology* / Q000378:metabolism
chemical_list: D029721:Drosophila Proteins; D007539:Isonicotinic Acids; D008565:Membrane Proteins; C530371:Qvr protein, Drosophila; D015735:Mifepristone; D017868:Cyclic AMP-Dependent Protein Kinases; D001973:Bromodeoxyuridine; C015300:isoguvacine
keywords: environmental cycles; sleep duration; stem cell regulation; tissue homeostasis