title: [Clock and molecular genetics in Drosophila].
abstract: Most living organisms possess a circadian clock (24 h period) which allows them to adapt to environmental conditions. Numerous studies in Drosophila allowed to discover various key clock genes, such as period and timeless. The powerful tools of drosophila genetics have shown that the molecular clock relies on negative feedback loops that generate oscillations of the clock genes mRNA. A delay between the accumulation of mRNAs and proteins is required for the feedback loop. It is generated by post-translational modifications as phosphorylations and ubiquitinations, which control protein stability and determine the period of their oscillations. Clock cells are present in brain as well as in multiple peripheric tissues where they run autonomously. The synchronisation of clock cells by light relies on cryptochrome in both brain and peripheral tissues. In the brain, synchronisation also involves the eye photoreceptors. The clock that drives sleep-wake rhythms is controlled by different groups of neurons in the brain. Each group has a distinct function in the generation of the behavioral rhythm and this function is modulated by environmental conditions.
authors.forename: Brigitte
authors.initials: B
authors.lastname: Grima
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology / Q000528:radiation effects; D001921:Brain / Q000502:physiology; D002940:Circadian Rhythm / Q000235:genetics* / Q000528:radiation effects; D056925:Circadian Rhythm Signaling Peptides and Proteins / Q000235:genetics* / Q000502:physiology; D056931:Cryptochromes / Q000502:physiology / Q000528:radiation effects; D029721:Drosophila Proteins / Q000235:genetics* / Q000502:physiology / Q000528:radiation effects; D004331:Drosophila melanogaster / Q000235:genetics* / Q000502:physiology / Q000528:radiation effects; D005136:Eye Proteins / Q000502:physiology / Q000528:radiation effects; D017344:Genes, Insect; D008027:Light; D008322:Mammals / Q000235:genetics / Q000502:physiology; D009474:Neurons / Q000145:classification / Q000502:physiology; D017956:Photoreceptor Cells, Invertebrate / Q000502:physiology / Q000528:radiation effects; D011499:Protein Processing, Post-Translational; D012333:RNA, Messenger / Q000235:genetics / Q000502:physiology; D012890:Sleep / Q000235:genetics / Q000502:physiology; D013045:Species Specificity; D014158:Transcription, Genetic; D014851:Wakefulness / Q000235:genetics / Q000502:physiology
chemical_list: D056925:Circadian Rhythm Signaling Peptides and Proteins; D056931:Cryptochromes; D029721:Drosophila Proteins; D005136:Eye Proteins; D012333:RNA, Messenger; C119828:cry protein, Drosophila