Neuronal Constituents and Putative Interactions Within the Drosophila Ellipsoid Body Neuropil

SummaryThe Drosophila core circadian circuit contains distinct groups of interacting neurons that give rise to diurnal sleep-wake patterns. Previous work showed that a subset of Dorsal Neurons 1 (DN1s) are sleep-promoting through their inhibition of activity-promoting circadian pacemakers. Here we show that these anterior-projecting DNs (APDNs) also “exit” the circadian circuitry and communicate with the homeostatic sleep center in higher brain regions to regulate sleep and sleep-wake arousal threshold. These APDNs connect to a small discrete subset of tubercular-bulbar neurons, which are connected in turn to specific sleep-centric Ellipsoid Body (EB)-Ring neurons of the central complex. Remarkably, activation of the APDNs produces sleep-like oscillations in the EB and also raises the arousal threshold, which requires neurotransmission throughout the circuit. The data indicate that this APDN-TuBusup-EB circuit temporally regulates sleep-wake arousal threshold in addition to the previously defined role of the TuBu-EB circuit in vision, navigation and attention.

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A Novel Drosophila Alkaline Phosphatase Specific to the Ellipsoid Body of the Adult Brain and the Lower Malpighian (Renal) Tubule

Genetics ◽

10.1093/genetics/154.1.285 ◽

2000 ◽

Vol 154 (1) ◽

pp. 285-297 ◽

Cited By ~ 1

Author(s):

Ming Yao Yang ◽

Zongsheng Wang ◽

Matthew MacPherson ◽

Julian A T Dow ◽

Kim Kaiser

Keyword(s):

Alkaline Phosphatase ◽

Expression Patterns ◽

Fluid Secretion ◽

Regulatory Elements ◽

Enhancer Trap ◽

Adult Brain ◽

P Element ◽

Renal Tubules ◽

Genomic Locus ◽

Ellipsoid Body

Abstract Two independent Drosophila melanogaster P{GAL4} enhancer-trap lines revealed identical GAL4-directed expression patterns in the ellipsoid body of the brain and in the Malpighian (renal) tubules in the abdomen. Both P-element insertions mapped to the same chromosomal site (100B2). The genomic locus, as characterized by plasmid rescue of flanking DNA, restriction mapping, and DNA sequencing, revealed the two P{GAL4} elements to be inserted in opposite orientations, only 46 bp apart. Three genes flanking the insertions have been identified. Calcineurin A1 (previously mapped to 21E-F) lies to one side, and two very closely linked genes lie to the other. The nearer encodes Aph-4, the first Drosophila alkaline phosphatase gene to be identified; the more distant gene [l(3)96601] is novel, with a head-elevated expression, and with distant similarity to transcription regulatory elements. Both in situ hybridization with Aph-4 probes and direct histochemical determination of alkaline phosphatase activity precisely matches the enhancer-trap pattern reported by the original lines. Although the P-element insertions are not recessive lethals, they display tubule phenotypes in both heterozygotes and homozygotes. Rates of fluid secretion in tubules from c507 homozygotes are reduced, both basally, and after stimulation by CAP2b, cAMP, or Drosophila leucokinin. The P-element insertions also disrupt the expression of Aph-4, causing misexpression in the tubule main segment. This disruption extends to tubule pigmentation, with c507 homozygotes displaying white-like transparent main segments. These results suggest that Aph-4, while possessing a very narrow range of expression, nonetheless plays an important role in epithelial function.

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Immunocytochemical Mapping of an RDL-Like GABA Receptor Subunit and of GABA in Brain Structures Related to Learning and Memory in the Cricket Acheta domesticus

Learning & Memory ◽

10.1101/lm.5.1.78 ◽

1998 ◽

Vol 5 (1) ◽

pp. 78-89

Author(s):

Colette Strambi ◽

Myriam Cayre ◽

David B. Sattelle ◽

Roger Augier ◽

Pierre Charpin ◽

...

Keyword(s):

Learning And Memory ◽

Gaba Receptors ◽

Antennal Lobe ◽

Gaba Receptor ◽

Brain Structures ◽

Acheta Domesticus ◽

Central Complex ◽

Mushroom Bodies ◽

Insect Brain ◽

Ellipsoid Body

The distribution of putative RDL-like GABA receptors and of γ-aminobutyric acid (GABA) in the brain of the adult house cricket Acheta domesticus was studied using specific antisera. Special attention was given to brain structures known to be related to learning and memory. The main immunostaining for the RDL-like GABA receptor was observed in mushroom bodies, in particular the upper part of mushroom body peduncle and the two arms of the posterior calyx. Weaker immunostaining was detected in the distal part of the peduncle and in the α and β lobes. The dorso- and ventrolateral protocerebrum neuropils appeared rich in RDL-like GABA receptors. Staining was also detected in the glomeruli of the antennal lobe, as well as in the ellipsoid body of the central complex. Many neurons clustered in groups exhibit GABA-like immunoreactivity. Tracts that were strongly immunostained innervated both the calyces and the lobes of mushroom bodies. The glomeruli of the antennal lobe, the ellipsoid body, as well as neuropils of the dorso- and ventrolateral protocerebrum were also rich in GABA-like immuno- reactivity. The data demonstrated a good correlation between the distribution of the GABA-like and of the RDL-like GABA receptor immunoreactivity. The prominent distribution of RDL-like GABA receptor subunits, in particular areas of mushroom bodies and antennal lobes, underlines the importance of inhibitory signals in information processing in these major integrative centers of the insect brain.

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Neuronal constituents and putative interactions within the Drosophila ellipsoid body neuropil

10.1101/394833 ◽

2018 ◽

Cited By ~ 1

Author(s):

Jaison Jiro Omoto ◽

Bao-Chau Minh Nguyen ◽

Pratyush Kandimalla ◽

Jennifer Kelly Lovick ◽

Jeffrey Michael Donlea ◽

...

Keyword(s):

Information Flow ◽

Cell Number ◽

Higher Order ◽

Central Complex ◽

Innervation Pattern ◽

Gal4 Driver ◽

Ellipsoid Body ◽

Cell Counts ◽

Central Brain ◽

Labeling Method

AbstractThe central complex (CX) is a midline-situated collection of neuropil compartments in the arthropod central brain, implicated in higher-order processes such as goal-directed navigation. Here, we provide a systematic genetic-neuroanatomical analysis of the ellipsoid body (EB), a compartment which represents a major afferent portal of the Drosophila CX. The neuropil volume of the EB, along with its prominent input compartment, called the bulb, is subdivided into precisely tessellated domains, distinguishable based on intensity of the global marker DN-cadherin. EB tangential elements (so-called ring neurons), most of which are derived from the DALv2 neuroblast lineage, interconnect the bulb and EB domains in a topographically-organized fashion. Using the DN-cadherin domains as a framework, we first characterized the bulb-EB connectivity by Gal4 driver lines expressed in different DALv2 ring neuron (R-neuron) subclasses. We identified 11 subclasses, 6 of which correspond to previously described projection patterns, and 5 novel patterns. These subclasses both spatially (based on EB innervation pattern) and numerically (cell counts) summate to the total EB volume and R-neuron cell number, suggesting that our compilation of R-neuron subclasses approaches completion. EB columnar elements, as well as non-DALv2 derived extrinsic ring neurons (ExR-neurons), were also incorporated into this anatomical framework. Finally, we addressed the connectivity between R-neurons and their targets, using the anterograde trans-synaptic labeling method, trans-Tango. This study demonstrates putative interactions of R-neuron subclasses and reveals general principles of information flow within the EB network. Our work will facilitate the generation and testing of hypotheses regarding circuit interactions within the EB and the rest of the CX.

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Two Clusters of GABAergic Ellipsoid Body Neurons Modulate Olfactory Labile Memory in Drosophila

Journal of Neuroscience ◽

10.1523/jneurosci.5365-12.2013 ◽

2013 ◽

Vol 33 (12) ◽

pp. 5175-5181 ◽

Cited By ~ 27

Author(s):

Z. Zhang ◽

X. Li ◽

J. Guo ◽

Y. Li ◽

A. Guo

Keyword(s):

Ellipsoid Body

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