Propagation of homeostatic sleep signals by segregated synaptic microcircuits of the Drosophila mushroom body

By Divya Sitaraman, Yoshinori Aso, Xin Jin, N. Chen, M. Felix, Gerald M. Rubin, M. Nitabach. 2015

138 citations recorded by the source corpus.

The Drosophila mushroom body (MB) is a key associative memory center that has also been implicated in the control of sleep. However, the identity of MB neurons underlying homeostatic sleep regulation, as well as the types of sleep signals generated by specific classes of MB neurons, has remained poorly understood. We recently identified two MB output neuron (MBON) classes whose axons convey sleep control signals from the MB to converge in the same downstream target region: a cholinergic sleep-promoting MBON class and a glutamatergic wake-promoting MBON class. Here we deploy a combination of neurogenetic, behavioral, and physiological approaches to identify and mechanistically dissect sleep-controlling circuits of the MB. Our studies reveal the existence of two segregated excitatory synaptic microcircuits that propagate homeostatic sleep information from different populations of intrinsic MB “Kenyon cells” (KCs) to specific sleep-regulating MBONs: sleep-promoting KCs increase sleep by preferentially activating the cholinergic MBONs, while wake-promoting KCs decrease sleep by preferentially activating the glutamatergic MBONs. Importantly, activity of the sleep-promoting MB microcircuit is increased by sleep deprivation and is necessary for homeostatic rebound sleep (i.e., the increased sleep that occurs after, and in compensation for, sleep lost during deprivation). These studies reveal for the first time specific functional connections between subsets of KCs and particular MBONs and establish the identity of synaptic microcircuits underlying transmission of homeostatic sleep signals in the MB.

Subfields: Cellular and Molecular Neuroscience, Endocrine and Autonomic Systems, Genetics

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Cellular and Molecular Neuroscience

In Endocrine and Autonomic Systems

In Genetics

Citations in the corpus

Dopaminergic neurons write and update memories with cell-type-specific rules (2016, background): “Recent work has shown that the g2a01 compartments play key roles in both sleep regulation and long-term memory (Sitaraman et al., 2015; Haynes et al., 2015).”