The Drosophila circuitry of sleep–wake regulation

AANAT1 functions in astrocytes to regulate sleep homeostasis

“…Glial cells have been increasingly implicated in mechanisms of baseline and homeostatic sleep regulation in mammals and flies [3-11], but it remains unknown whether and how glia might influence monoaminergic control of sleep. Sleep is regulated by circadian rhythms and a homeostatic drive to compensate for prolonged wakefulness, andgrowing evidence suggests that neural mechanisms controlling homeostatic sleep can be discriminated from those controlling baseline sleep [12][13][14][15]. In Drosophila, mutants of arylalkylamine N-acetyltransferase 1 (AANAT1 lo ) have normal baseline amounts of sleep and motor activity, but increased rebound sleep following deprivation [16].…”

“…growing evidence suggests that neural mechanisms controlling homeostatic sleep can be discriminated from those controlling baseline sleep [12][13][14][15]. In Drosophila, mutants of arylalkylamine N-acetyltransferase 1 (AANAT1 lo ) have normal baseline amounts of sleep and motor activity, but increased rebound sleep following deprivation [16].…”

“…The monoamines serotonin, dopamine, and octopamine (the insect homolog of norepinephrine) are known to act in the fly brain to regulate the quantity and timing of sleep [2]. Pharmacological, genetic, and thermogenetic approaches have converged to demonstrate that serotonin signaling in the fly brain increases sleep, whereas dopamine or octopamine signaling promote waking [2,12,[18][19][20][21][22]. Previous studies have suggested AANAT1 expression in dopaminergic neurons [23,24], but this has not been tested directly.…”

Nuclear transcriptomes of the seven neuronal cell types that constitute theDrosophilamushroom bodies

“…An arsenal of genetic tools to manipulate any gene's function within each of these cell subtypes already exists (109,110). In addition to olfactory associative memory, MBs also play fundamental roles in other forms of memory including visual and gustatory (9, 10), temperature preference (11), courtship behaviors (79,80), stress response (92), food-seeking (111), sleep (12) and responses to ethanol (13). This dataset will facilitate the discovery of neural mechanisms for each of these conserved behaviors.…”

“…A primary site of associative learning in insects is the mushroom body (MB) (1)(2)(3)(4)(6)(7)(8), a paired brain structure that in Drosophila is comprised of approximately 2000 intrinsic Kenyon Cells (KCs) per hemisphere. MBs in fruit flies are critical sites of olfactory, visual and gustatory learning (1-4, 9, 10), and also play important roles in other behavioral contexts such as temperature preferences (11), sleep (12) and responses to ethanol exposure (13).…”