Genetics of Sleep and Sleep Disorders Amita Sehgal, Emmanuel Mignot  Cell  Volume 146, Issue 2, Pages 194-207 (July 2011) DOI: 10.1016/j.cell.2011.07.004 Copyright © 2011 Elsevier Inc. Terms and Conditions

Figure 1 An Example of a Conserved Mechanism Underlying Sleep In both Drosophila and mammals, an arousal-promoting peptide (PDF and hypocretin, respectively) is secreted by cells within, or in the vicinity of, the central clock network. In mammals, hypocretin-producing neurons in the lateral hypothalamus receive circadian inputs from the central clock in the suprachaismatic nucleus (SCN) via the dorsomedial hypothalamus (DMH). (Circadian inputs are indicated in the lighter shaded box.) They are inhibited by GABAergic inputs from the ventrolateral preoptic (VLPO) area. In Drosophila, the large ventral lateral neurons (lLNvs) are part of the clock network although they are not required for free-running circadian rhythms. Instead they mediate light-driven arousal, at least in part through the release of PDF. As in mammals, GABAergic inputs to these neurons promote sleep. Cell 2011 146, 194-207DOI: (10.1016/j.cell.2011.07.004) Copyright © 2011 Elsevier Inc. Terms and Conditions