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Musso PY, Junca P, Gordon MD. A neural circuit linking two sugar sensors regulates satiety-dependent fructose drive in Drosophila. SCIENCE ADVANCES 2021; 7:eabj0186. [PMID: 34851668 PMCID: PMC8635442 DOI: 10.1126/sciadv.abj0186] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
In flies, neuronal sensors detect prandial changes in circulating fructose levels and either sustain or terminate feeding, depending on internal state. Here, we describe a three-part neural circuit that imparts satiety-dependent modulation of fructose sensing. We show that dorsal fan-shaped body neurons display oscillatory calcium activity when hemolymph glucose is high and that these oscillations require glutamatergic input from SLP-AB or “Janus” neurons projecting from the protocerebrum to the asymmetric body. Suppression of activity in this circuit, either by starvation or by genetic silencing, promotes specific drive for fructose ingestion. This is achieved through neuropeptidergic signaling by tachykinin, which is released from the fan-shaped body when glycemia is high. Tachykinin, in turn, signals to Gr43a-positive fructose sensors to modulate their response to fructose. Together, our results demonstrate how a three-layer neural circuit links the detection of two sugars to produce precise satiety-dependent control of feeding behavior.
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2
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Hugin + neurons provide a link between sleep homeostat and circadian clock neurons. Proc Natl Acad Sci U S A 2021; 118:2111183118. [PMID: 34782479 DOI: 10.1073/pnas.2111183118] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/13/2021] [Indexed: 11/18/2022] Open
Abstract
Sleep is controlled by homeostatic mechanisms, which drive sleep after wakefulness, and a circadian clock, which confers the 24-h rhythm of sleep. These processes interact with each other to control the timing of sleep in a daily cycle as well as following sleep deprivation. However, the mechanisms by which they interact are poorly understood. We show here that hugin + neurons, previously identified as neurons that function downstream of the clock to regulate rhythms of locomotor activity, are also targets of the sleep homeostat. Sleep deprivation decreases activity of hugin + neurons, likely to suppress circadian-driven activity during recovery sleep, and ablation of hugin + neurons promotes sleep increases generated by activation of the homeostatic sleep locus, the dorsal fan-shaped body (dFB). Also, mutations in peptides produced by the hugin + locus increase recovery sleep following deprivation. Transsynaptic mapping reveals that hugin + neurons feed back onto central clock neurons, which also show decreased activity upon sleep loss, in a Hugin peptide-dependent fashion. We propose that hugin + neurons integrate circadian and sleep signals to modulate circadian circuitry and regulate the timing of sleep.
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3
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Scaplen KM, Talay M, Fisher JD, Cohn R, Sorkaç A, Aso Y, Barnea G, Kaun KR. Transsynaptic mapping of Drosophila mushroom body output neurons. eLife 2021; 10:e63379. [PMID: 33570489 PMCID: PMC7877909 DOI: 10.7554/elife.63379] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 01/26/2021] [Indexed: 11/13/2022] Open
Abstract
The mushroom body (MB) is a well-characterized associative memory structure within the Drosophila brain. Analyzing MB connectivity using multiple approaches is critical for understanding the functional implications of this structure. Using the genetic anterograde transsynaptic tracing tool, trans-Tango, we identified divergent projections across the brain and convergent downstream targets of the MB output neurons (MBONs). Our analysis revealed at least three separate targets that receive convergent input from MBONs: other MBONs, the fan-shaped body (FSB), and the lateral accessory lobe (LAL). We describe, both anatomically and functionally, a multilayer circuit in which inhibitory and excitatory MBONs converge on the same genetic subset of FSB and LAL neurons. This circuit architecture enables the brain to update and integrate information with previous experience before executing appropriate behavioral responses. Our use of trans-Tango provides a genetically accessible anatomical framework for investigating the functional relevance of components within these complex and interconnected circuits.
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Affiliation(s)
- Kristin M Scaplen
- Department of Neuroscience, Brown UniversityProvidenceUnited States
- Department of Psychology, Bryant UniversitySmithfieldUnited States
- Center for Health and Behavioral Sciences, Bryant UniversitySmithfieldUnited States
| | - Mustafa Talay
- Department of Neuroscience, Brown UniversityProvidenceUnited States
| | - John D Fisher
- Department of Neuroscience, Brown UniversityProvidenceUnited States
| | - Raphael Cohn
- Laboratory of Neurophysiology and Behavior, The Rockefeller UniversityNew YorkUnited States
| | - Altar Sorkaç
- Department of Neuroscience, Brown UniversityProvidenceUnited States
| | - Yoshi Aso
- Janelia Research Campus, Howard Hughes Medical InstituteAshburnUnited States
| | - Gilad Barnea
- Department of Neuroscience, Brown UniversityProvidenceUnited States
| | - Karla R Kaun
- Department of Neuroscience, Brown UniversityProvidenceUnited States
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4
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Hensgen R, England L, Homberg U, Pfeiffer K. Neuroarchitecture of the central complex in the brain of the honeybee: Neuronal cell types. J Comp Neurol 2020; 529:159-186. [PMID: 32374034 DOI: 10.1002/cne.24941] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 04/30/2020] [Accepted: 04/30/2020] [Indexed: 12/11/2022]
Abstract
The central complex (CX) in the insect brain is a higher order integration center that controls a number of behaviors, most prominently goal directed locomotion. The CX comprises the protocerebral bridge (PB), the upper division of the central body (CBU), the lower division of the central body (CBL), and the paired noduli (NO). Although spatial orientation has been extensively studied in honeybees at the behavioral level, most electrophysiological and anatomical analyses have been carried out in other insect species, leaving the morphology and physiology of neurons that constitute the CX in the honeybee mostly enigmatic. The goal of this study was to morphologically identify neuronal cell types of the CX in the honeybee Apis mellifera. By performing iontophoretic dye injections into the CX, we traced 16 subtypes of neuron that connect a subdivision of the CX with other regions in the bee's central brain, and eight subtypes that mainly interconnect different subdivisions of the CX. They establish extensive connections between the CX and the lateral complex, the superior protocerebrum and the posterior protocerebrum. Characterized neuron classes and subtypes are morphologically similar to those described in other insects, suggesting considerable conservation in the neural network relevant for orientation.
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Affiliation(s)
- Ronja Hensgen
- Animal Physiology, Department of Biology, Philipps-Universität Marburg, Marburg, Germany
| | - Laura England
- Animal Physiology, Department of Biology, Philipps-Universität Marburg, Marburg, Germany
| | - Uwe Homberg
- Animal Physiology, Department of Biology, Philipps-Universität Marburg, Marburg, Germany
| | - Keram Pfeiffer
- Behavioral Physiology and Sociobiology (Zoology II), Biozentrum, University of Würzburg, Würzburg, Germany
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5
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Shiozaki HM, Ohta K, Kazama H. A Multi-regional Network Encoding Heading and Steering Maneuvers in Drosophila. Neuron 2020; 106:126-141.e5. [PMID: 32023429 DOI: 10.1016/j.neuron.2020.01.009] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2019] [Revised: 12/11/2019] [Accepted: 01/10/2020] [Indexed: 11/25/2022]
Abstract
An internal sense of heading direction is computed from various cues, including steering maneuvers of the animal. Although neurons encoding heading and steering have been found in multiple brain regions, it is unclear whether and how they are organized into neural circuits. Here we show that, in flying Drosophila, heading and turning behaviors are encoded by population dynamics of specific cell types connecting the subregions of the central complex (CX), a brain structure implicated in navigation. Columnar neurons in the fan-shaped body (FB) of the CX exhibit circular dynamics that multiplex information about turning behavior and heading. These dynamics are coordinated with those in the ellipsoid body, another CX subregion containing a heading representation, although only FB neurons flip turn preference depending on the visual environment. Thus, the navigational system spans multiple subregions of the CX, where specific cell types show coordinated but distinct context-dependent dynamics.
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Affiliation(s)
- Hiroshi M Shiozaki
- RIKEN Center for Brain Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
| | - Kazumi Ohta
- RIKEN Center for Brain Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Hokto Kazama
- RIKEN Center for Brain Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; RIKEN CBS-KAO Collaboration Center, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan; Graduate School of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902, Japan.
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6
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Hu W, Peng Y, Sun J, Zhang F, Zhang X, Wang L, Li Q, Zhong Y. Fan-Shaped Body Neurons in the Drosophila Brain Regulate Both Innate and Conditioned Nociceptive Avoidance. Cell Rep 2020; 24:1573-1584. [PMID: 30089267 DOI: 10.1016/j.celrep.2018.07.028] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Revised: 04/29/2018] [Accepted: 07/06/2018] [Indexed: 01/27/2023] Open
Abstract
Multiple brain regions respond to harmful nociceptive stimuli. However, it remains unclear as to whether behavioral avoidance of such stimuli can be modulated within the same or distinct brain networks. Here, we found subgroups of neurons localized within a well-defined brain region capable of mediating both innate and conditioned nociceptive avoidance in Drosophila. Neurons in the ventral, but not the dorsal, of the multiple-layer organized fan-shaped body (FB) are responsive to electric shock (ES). Silencing ES-responsive neurons, but not non-responsive neurons, leads to reduced avoidance of harmful stimuli, including ES and heat shock. Activating these neurons consistently triggers avoidance and can serve as an unconditional stimulus in an aversive classical conditioning task. Among the three groups of responsive neurons identified, two also have reduced activity in ES-conditioned odor avoidance. These results demonstrate that both innate and conditioned nociceptive avoidance might be represented within neurons confined to a single brain region.
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Affiliation(s)
- Wantong Hu
- Tsinghua-Peking Center for Life Sciences, IDG/McGovern Institute for Brain Research, MOE Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Yiqing Peng
- Tsinghua-Peking Center for Life Sciences, IDG/McGovern Institute for Brain Research, MOE Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Jiameng Sun
- Tsinghua-Peking Center for Life Sciences, IDG/McGovern Institute for Brain Research, MOE Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Fang Zhang
- Tsinghua-Peking Center for Life Sciences, IDG/McGovern Institute for Brain Research, MOE Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Xuchen Zhang
- Tsinghua-Peking Center for Life Sciences, IDG/McGovern Institute for Brain Research, MOE Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Lianzhang Wang
- Tsinghua-Peking Center for Life Sciences, IDG/McGovern Institute for Brain Research, MOE Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Qian Li
- Tsinghua-Peking Center for Life Sciences, IDG/McGovern Institute for Brain Research, MOE Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China.
| | - Yi Zhong
- Tsinghua-Peking Center for Life Sciences, IDG/McGovern Institute for Brain Research, MOE Key Laboratory of Protein Sciences, School of Life Sciences, Tsinghua University, Beijing 100084, China.
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von Hadeln J, Hensgen R, Bockhorst T, Rosner R, Heidasch R, Pegel U, Quintero Pérez M, Homberg U. Neuroarchitecture of the central complex of the desert locust: Tangential neurons. J Comp Neurol 2019; 528:906-934. [PMID: 31625611 DOI: 10.1002/cne.24796] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 10/10/2019] [Accepted: 10/11/2019] [Indexed: 12/11/2022]
Abstract
The central complex (CX) comprises a group of midline neuropils in the insect brain, consisting of the protocerebral bridge (PB), the upper (CBU) and lower division (CBL) of the central body and a pair of globular noduli. It receives prominent input from the visual system and plays a major role in spatial orientation of the animals. Vertical slices and horizontal layers of the CX are formed by columnar, tangential, and pontine neurons. While pontine and columnar neurons have been analyzed in detail, especially in the fruit fly and desert locust, understanding of the organization of tangential cells is still rudimentary. As a basis for future functional studies, we have studied the morphologies of tangential neurons of the CX of the desert locust Schistocerca gregaria. Intracellular dye injections revealed 43 different types of tangential neuron, 8 of the PB, 5 of the CBL, 24 of the CBU, 2 of the noduli, and 4 innervating multiple substructures. Cell bodies of these neurons were located in 11 different clusters in the cell body rind. Judging from the presence of fine versus beaded terminals, the vast majority of these neurons provide input into the CX, especially from the lateral complex (LX), the superior protocerebrum, the posterior slope, and other surrounding brain areas, but not directly from the mushroom bodies. Connections are largely subunit- and partly layer-specific. No direct connections were found between the CBU and the CBL. Instead, both subdivisions are connected in parallel with the PB and distinct layers of the noduli.
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Affiliation(s)
- Joss von Hadeln
- Fachbereich Biologie, Tierphysiologie, and Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Germany
| | - Ronja Hensgen
- Fachbereich Biologie, Tierphysiologie, and Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Germany
| | - Tobias Bockhorst
- Fachbereich Biologie, Tierphysiologie, and Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Germany
| | - Ronny Rosner
- Fachbereich Biologie, Tierphysiologie, and Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Germany
| | - Ronny Heidasch
- Fachbereich Biologie, Tierphysiologie, and Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Germany
| | - Uta Pegel
- Fachbereich Biologie, Tierphysiologie, and Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Germany
| | - Manuel Quintero Pérez
- Fachbereich Biologie, Tierphysiologie, and Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Germany
| | - Uwe Homberg
- Fachbereich Biologie, Tierphysiologie, and Center for Mind, Brain and Behavior (CMBB), University of Marburg and Justus Liebig University Giessen, Germany
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8
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Temporal and spatial order of photoreceptor and glia projections into optic lobe in Drosophila. Sci Rep 2018; 8:12669. [PMID: 30140062 PMCID: PMC6107658 DOI: 10.1038/s41598-018-30415-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 07/25/2018] [Indexed: 11/10/2022] Open
Abstract
Photoreceptor (PR) axons project from the retina to the optic lobe in brain and form a precise retinotopic map in the Drosophila visual system. Yet the role of retinal basal glia in the retinotopic map formation is not previously known. We examined the formation of the retinotopic map by marking single PR pairs and following their axonal projections. In addition to confirming previous studies that the spatial information is preserved from the retina to the optic stalk and then to the optic lamina, we found that the young PR R3/4 axons transiently overshoot and then retract to their final destination, the lamina plexus. We then examined the process of wrapping glia (WG) membrane extension in the eye disc and showed that the WG membrane extensions also follow the retinotopic map. We show that the WG is important for the proper spatial distribution of PR axons in the optic stalk and lamina, suggesting an active role of wrapping glia in the retinotopic map formation.
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9
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Hangover Links Nuclear RNA Signaling to cAMP Regulation via the Phosphodiesterase 4d Ortholog dunce. Cell Rep 2017; 18:533-544. [PMID: 28076795 DOI: 10.1016/j.celrep.2016.12.048] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Revised: 09/28/2016] [Accepted: 12/14/2016] [Indexed: 11/20/2022] Open
Abstract
The hangover gene defines a cellular stress pathway that is required for rapid ethanol tolerance in Drosophila melanogaster. To understand how cellular stress changes neuronal function, we analyzed Hangover function on a cellular and neuronal level. We provide evidence that Hangover acts as a nuclear RNA binding protein and we identified the phosphodiesterase 4d ortholog dunce as a target RNA. We generated a transcript-specific dunce mutant that is impaired not only in ethanol tolerance but also in the cellular stress response. At the neuronal level, Dunce and Hangover are required in the same neuron pair to regulate experience-dependent motor output. Within these neurons, two cyclic AMP (cAMP)-dependent mechanisms balance the degree of tolerance. The balance is achieved by feedback regulation of Hangover and dunce transcript levels. This study provides insight into how nuclear Hangover/RNA signaling is linked to the cytoplasmic regulation of cAMP levels and results in neuronal adaptation and behavioral changes.
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10
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Chouhan NS, Mohan K, Ghose A. cAMP signaling mediates behavioral flexibility and consolidation of social status in Drosophila aggression. ACTA ACUST UNITED AC 2017; 220:4502-4514. [PMID: 28993465 DOI: 10.1242/jeb.165811] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 10/04/2017] [Indexed: 12/19/2022]
Abstract
Social rituals, such as male-male aggression in Drosophila, are often stereotyped and the component behavioral patterns modular. The likelihood of transition from one behavioral pattern to another is malleable by experience and confers flexibility to the behavioral repertoire. Experience-dependent modification of innate aggressive behavior in flies alters fighting strategies during fights and establishes dominant-subordinate relationships. Dominance hierarchies resulting from agonistic encounters are consolidated to longer-lasting, social-status-dependent behavioral modifications, resulting in a robust loser effect. We showed that cAMP dynamics regulated by the calcium-calmodulin-dependent adenylyl cyclase, Rut, and the cAMP phosphodiesterase, Dnc, but not the Amn gene product, in specific neuronal groups of the mushroom body and central complex, mediate behavioral plasticity necessary to establish dominant-subordinate relationships. rut and dnc mutant flies were unable to alter fighting strategies and establish dominance relationships during agonistic interactions. This real-time flexibility during a fight was independent of changes in aggression levels. Longer-term consolidation of social status in the form of a loser effect, however, required additional Amn-dependent inputs to cAMP signaling and involved a circuit-level association between the α/β and γ neurons of the mushroom body. Our findings implicate cAMP signaling in mediating the plasticity of behavioral patterns in aggressive behavior and in the generation of a temporally stable memory trace that manifests as a loser effect.
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Affiliation(s)
- Nitin Singh Chouhan
- Biology Division, Indian Institute of Science Education and Research (IISER) Pune, Dr. Homi Bhabha Road, Pune 411 008, India
| | - Krithika Mohan
- Biology Division, Indian Institute of Science Education and Research (IISER) Pune, Dr. Homi Bhabha Road, Pune 411 008, India
| | - Aurnab Ghose
- Biology Division, Indian Institute of Science Education and Research (IISER) Pune, Dr. Homi Bhabha Road, Pune 411 008, India
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11
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Namiki S, Kanzaki R. Comparative Neuroanatomy of the Lateral Accessory Lobe in the Insect Brain. Front Physiol 2016; 7:244. [PMID: 27445837 PMCID: PMC4917559 DOI: 10.3389/fphys.2016.00244] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2016] [Accepted: 06/03/2016] [Indexed: 11/13/2022] Open
Abstract
The lateral accessory lobe (LAL) mediates signals from the central complex to the thoracic motor centers. The results obtained from different insects suggest that the LAL is highly relevant to the locomotion. Perhaps due to its deep location and lack of clear anatomical boundaries, few studies have focused on this brain region. Systematic data of LAL interneurons are available in the silkmoth. We here review individual neurons constituting the LAL by comparing the silkmoth and other insects. The survey through the connectivity and intrinsic organization suggests potential homology in the organization of the LAL among insects.
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Affiliation(s)
- Shigehiro Namiki
- Research Center for Advanced Science and Technology, The University of Tokyo Tokyo, Japan
| | - Ryohei Kanzaki
- Research Center for Advanced Science and Technology, The University of Tokyo Tokyo, Japan
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12
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Information flow through neural circuits for pheromone orientation. Nat Commun 2014; 5:5919. [DOI: 10.1038/ncomms6919] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 11/20/2014] [Indexed: 11/08/2022] Open
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13
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Abstract
Sleep is under homeostatic control, but the mechanisms that sense sleep need and correct sleep deficits remain unknown. Here, we report that sleep-promoting neurons with projections to the dorsal fan-shaped body (FB) form the output arm of Drosophila's sleep homeostat. Homeostatic sleep control requires the Rho-GTPase-activating protein encoded by the crossveinless-c (cv-c) gene in order to transduce sleep pressure into increased electrical excitability of dorsal FB neurons. cv-c mutants exhibit decreased sleep time, diminished sleep rebound, and memory deficits comparable to those after sleep loss. Targeted ablation and rescue of Cv-c in sleep-control neurons of the dorsal FB impair and restore, respectively, normal sleep patterns. Sleep deprivation increases the excitability of dorsal FB neurons, but this homeostatic adjustment is disrupted in short-sleeping cv-c mutants. Sleep pressure thus shifts the input-output function of sleep-promoting neurons toward heightened activity by modulating ion channel function in a mechanism dependent on Cv-c.
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14
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Sakurai T, Namiki S, Kanzaki R. Molecular and neural mechanisms of sex pheromone reception and processing in the silkmoth Bombyx mori. Front Physiol 2014; 5:125. [PMID: 24744736 PMCID: PMC3978319 DOI: 10.3389/fphys.2014.00125] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 03/13/2014] [Indexed: 12/01/2022] Open
Abstract
Male moths locate their mates using species-specific sex pheromones emitted by conspecific females. One striking feature of sex pheromone recognition in males is the high degree of specificity and sensitivity at all levels, from the primary sensory processes to behavior. The silkmoth Bombyx mori is an excellent model insect in which to decipher the underlying mechanisms of sex pheromone recognition due to its simple sex pheromone communication system, where a single pheromone component, bombykol, elicits the full sexual behavior of male moths. Various technical advancements that cover all levels of analysis from molecular to behavioral also allow the systematic analysis of pheromone recognition mechanisms. Sex pheromone signals are detected by pheromone receptors expressed in olfactory receptor neurons in the pheromone-sensitive sensilla trichodea on male antennae. The signals are transmitted to the first olfactory processing center, the antennal lobe (AL), and then are processed further in the higher centers (mushroom body and lateral protocerebrum) to elicit orientation behavior toward females. In recent years, significant progress has been made elucidating the molecular mechanisms underlying the detection of sex pheromones. In addition, extensive studies of the AL and higher centers have provided insights into the neural basis of pheromone processing in the silkmoth brain. This review describes these latest advances, and discusses what these advances have revealed about the mechanisms underlying the specific and sensitive recognition of sex pheromones in the silkmoth.
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Affiliation(s)
- Takeshi Sakurai
- Intelligent Cooperative Systems, Research Center for Advanced Science and Technology, The University of Tokyo Meguro-ku, Japan
| | - Shigehiro Namiki
- Intelligent Cooperative Systems, Research Center for Advanced Science and Technology, The University of Tokyo Meguro-ku, Japan
| | - Ryohei Kanzaki
- Intelligent Cooperative Systems, Research Center for Advanced Science and Technology, The University of Tokyo Meguro-ku, Japan
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15
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Yang JS, Awasaki T, Yu HH, He Y, Ding P, Kao JC, Lee T. Diverse neuronal lineages make stereotyped contributions to the Drosophila locomotor control center, the central complex. J Comp Neurol 2014; 521:2645-Spc1. [PMID: 23696496 DOI: 10.1002/cne.23339] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Accepted: 03/29/2013] [Indexed: 12/11/2022]
Abstract
The Drosophila central brain develops from a fixed number of neuroblasts. Each neuroblast makes a clone of neurons that exhibit common trajectories. Here we identified 15 distinct clones that carry larval-born neurons innervating the Drosophila central complex (CX), which consists of four midline structures including the protocerebral bridge (PB), fan-shaped body (FB), ellipsoid body (EB), and noduli (NO). Clonal analysis revealed that the small-field CX neurons, which establish intricate projections across different CX substructures, exist in four isomorphic groups that respectively derive from four complex posterior asense-negative lineages. In terms of the region-characteristic large-field CX neurons, we found that two lineages make PB neurons, 10 lineages produce FB neurons, three lineages generate EB neurons, and two lineages yield NO neurons. The diverse FB developmental origins reflect the discrete input pathways for different FB subcompartments. Clonal analysis enlightens both development and anatomy of the insect locomotor control center.
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Affiliation(s)
- Jacob S Yang
- Howard Hughes Medical Institute, Janelia Farm Research Campus, 19700 Helix Drive, Ashburn, VA, USA
| | - Takeshi Awasaki
- Howard Hughes Medical Institute, Janelia Farm Research Campus, 19700 Helix Drive, Ashburn, VA, USA
| | - Hung-Hsiang Yu
- Howard Hughes Medical Institute, Janelia Farm Research Campus, 19700 Helix Drive, Ashburn, VA, USA
| | - Yisheng He
- Department of Neurobiology, University of Massachusetts, 364 Plantation Street, Worcester, MA, USA
| | - Peng Ding
- Department of Neurobiology, University of Massachusetts, 364 Plantation Street, Worcester, MA, USA
| | - Jui-Chun Kao
- Department of Neurobiology, University of Massachusetts, 364 Plantation Street, Worcester, MA, USA
| | - Tzumin Lee
- Howard Hughes Medical Institute, Janelia Farm Research Campus, 19700 Helix Drive, Ashburn, VA, USA.,Department of Neurobiology, University of Massachusetts, 364 Plantation Street, Worcester, MA, USA
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16
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Weir PT, Schnell B, Dickinson MH. Central complex neurons exhibit behaviorally gated responses to visual motion in Drosophila. J Neurophysiol 2014; 111:62-71. [DOI: 10.1152/jn.00593.2013] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Sensory systems provide abundant information about the environment surrounding an animal, but only a small fraction of that information is relevant for any given task. One example of this requirement for context-dependent filtering of a sensory stream is the role that optic flow plays in guiding locomotion. Flying animals, which do not have access to a direct measure of ground speed, rely on optic flow to regulate their forward velocity. This observation suggests that progressive optic flow, the pattern of front-to-back motion on the retina created by forward motion, should be especially salient to an animal while it is in flight, but less important while it is standing still. We recorded the activity of cells in the central complex of Drosophila melanogaster during quiescence and tethered flight using both calcium imaging and whole cell patch-clamp techniques. We observed a genetically identified set of neurons in the fan-shaped body that are unresponsive to visual motion while the animal is quiescent. During flight their baseline activity increases, and they respond to front-to-back motion with changes relative to this baseline. The results provide an example of how nervous systems selectively respond to complex sensory stimuli depending on the current behavioral state of the animal.
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Affiliation(s)
- Peter T. Weir
- Department of Biology, University of Washington, Seattle, Washington
| | - Bettina Schnell
- Department of Biology, University of Washington, Seattle, Washington
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Pfeiffer K, Homberg U. Organization and functional roles of the central complex in the insect brain. ANNUAL REVIEW OF ENTOMOLOGY 2014; 59:165-84. [PMID: 24160424 DOI: 10.1146/annurev-ento-011613-162031] [Citation(s) in RCA: 245] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
The central complex is a group of modular neuropils across the midline of the insect brain. Hallmarks of its anatomical organization are discrete layers, an organization into arrays of 16 slices along the right-left axis, and precise inter-hemispheric connections via chiasmata. The central complex is connected most prominently with the adjacent lateral complex and the superior protocerebrum. Its developmental appearance corresponds with the appearance of compound eyes and walking legs. Distinct dopaminergic neurons control various forms of arousal. Electrophysiological studies provide evidence for roles in polarized light vision, sky compass orientation, and integration of spatial information for locomotor control. Behavioral studies on mutant and transgenic flies indicate roles in spatial representation of visual cues, spatial visual memory, directional control of walking and flight, and place learning. The data suggest that spatial azimuthal directions (i.e., where) are represented in the slices, and cue information (i.e., what) are represented in different layers of the central complex.
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Affiliation(s)
- Keram Pfeiffer
- Faculty of Biology, Animal Physiology, University of Marburg, 35032 Marburg, Germany; ,
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18
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Lin CY, Chuang CC, Hua TE, Chen CC, Dickson BJ, Greenspan RJ, Chiang AS. A comprehensive wiring diagram of the protocerebral bridge for visual information processing in the Drosophila brain. Cell Rep 2013; 3:1739-53. [PMID: 23707064 DOI: 10.1016/j.celrep.2013.04.022] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 03/12/2013] [Accepted: 04/25/2013] [Indexed: 11/19/2022] Open
Abstract
How the brain perceives sensory information and generates meaningful behavior depends critically on its underlying circuitry. The protocerebral bridge (PB) is a major part of the insect central complex (CX), a premotor center that may be analogous to the human basal ganglia. Here, by deconstructing hundreds of PB single neurons and reconstructing them into a common three-dimensional framework, we have constructed a comprehensive map of PB circuits with labeled polarity and predicted directions of information flow. Our analysis reveals a highly ordered information processing system that involves directed information flow among CX subunits through 194 distinct PB neuron types. Circuitry properties such as mirroring, convergence, divergence, tiling, reverberation, and parallel signal propagation were observed; their functional and evolutional significance is discussed. This layout of PB neuronal circuitry may provide guidelines for further investigations on transformation of sensory (e.g., visual) input into locomotor commands in fly brains.
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Affiliation(s)
- Chih-Yung Lin
- Institute of Biotechnology and Department of Life Science, National Tsing Hua University, Hsinchu 30013, Taiwan
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19
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Heinze S, Florman J, Asokaraj S, El Jundi B, Reppert SM. Anatomical basis of sun compass navigation II: the neuronal composition of the central complex of the monarch butterfly. J Comp Neurol 2013; 521:267-98. [PMID: 22886450 DOI: 10.1002/cne.23214] [Citation(s) in RCA: 114] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Revised: 08/01/2012] [Accepted: 08/03/2012] [Indexed: 12/25/2022]
Abstract
Each fall, eastern North American monarch butterflies in their northern range undergo a long-distance migration south to their overwintering grounds in Mexico. Migrants use a time-compensated sun compass to determine directionality during the migration. This compass system uses information extracted from sun-derived skylight cues that is compensated for time of day and ultimately transformed into the appropriate motor commands. The central complex (CX) is likely the site of the actual sun compass, because neurons in this brain region are tuned to specific skylight cues. To help illuminate the neural basis of sun compass navigation, we examined the neuronal composition of the CX and its associated brain regions. We generated a standardized version of the sun compass neuropils, providing reference volumes, as well as a common frame of reference for the registration of neuron morphologies. Volumetric comparisons between migratory and nonmigratory monarchs substantiated the proposed involvement of the CX and related brain areas in migratory behavior. Through registration of more than 55 neurons of 34 cell types, we were able to delineate the major input pathways to the CX, output pathways, and intrinsic neurons. Comparison of these neural elements with those of other species, especially the desert locust, revealed a surprising degree of conservation. From these interspecies data, we have established key components of a conserved core network of the CX, likely complemented by species-specific neurons, which together may comprise the neural substrates underlying the computations performed by the CX.
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Affiliation(s)
- Stanley Heinze
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, Massachusetts 01605, USA.
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Zhang X, Ren Q, Guo A. Parallel pathways for cross-modal memory retrieval in Drosophila. J Neurosci 2013; 33:8784-93. [PMID: 23678121 PMCID: PMC6618838 DOI: 10.1523/jneurosci.4631-12.2013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Revised: 04/07/2013] [Accepted: 04/08/2013] [Indexed: 11/21/2022] Open
Abstract
Memory-retrieval processing of cross-modal sensory preconditioning is vital for understanding the plasticity underlying the interactions between modalities. As part of the sensory preconditioning paradigm, it has been hypothesized that the conditioned response to an unreinforced cue depends on the memory of the reinforced cue via a sensory link between the two cues. To test this hypothesis, we studied cross-modal memory-retrieval processing in a genetically tractable model organism, Drosophila melanogaster. By expressing the dominant temperature-sensitive shibire(ts1) (shi(ts1)) transgene, which blocks synaptic vesicle recycling of specific neural subsets with the Gal4/UAS system at the restrictive temperature, we specifically blocked visual and olfactory memory retrieval, either alone or in combination; memory acquisition remained intact for these modalities. Blocking the memory retrieval of the reinforced olfactory cues did not impair the conditioned response to the unreinforced visual cues or vice versa, in contrast to the canonical memory-retrieval processing of sensory preconditioning. In addition, these conditioned responses can be abolished by blocking the memory retrieval of the two modalities simultaneously. In sum, our results indicated that a conditioned response to an unreinforced cue in cross-modal sensory preconditioning can be recalled through parallel pathways.
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Affiliation(s)
- Xiaonan Zhang
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences (CAS), Beijing 100101, China
- University of CAS, Beijing 100049, China
| | - Qingzhong Ren
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, CAS, Shanghai 200031, China, and
| | - Aike Guo
- State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences (CAS), Beijing 100101, China
- Institute of Neuroscience, State Key Laboratory of Neuroscience, Shanghai Institutes for Biological Sciences, CAS, Shanghai 200031, China, and
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21
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Ten-a affects the fusion of central complex primordia in Drosophila. PLoS One 2013; 8:e57129. [PMID: 23437330 PMCID: PMC3577759 DOI: 10.1371/journal.pone.0057129] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2012] [Accepted: 01/17/2013] [Indexed: 02/03/2023] Open
Abstract
The central complex of Drosophila melanogaster plays important functions in various behaviors, such as visual and olfactory memory, visual orientation, sleep, and movement control. However little is known about the genes regulating the development of the central complex. Here we report that a mutant gene affecting central complex morphology, cbd (central brain defect), was mapped to ten-a, a type II trans-membrane protein coding gene. Down-regulation of ten-a in pan-neural cells contributed to abnormal morphology of central complex. Over-expression of ten-a by C767-Gal4 was able to partially restore the abnormal central complex morphology in the cbd mutant. Tracking the development of FB primordia revealed that C767-Gal4 labeled interhemispheric junction that separated fan-shaped body precursors at larval stage withdrew to allow the fusion of the precursors. While the C767-Gal4 labeled structure did not withdraw properly and detached from FB primordia, the two fan-shaped body precursors failed to fuse in the cbd mutant. We propose that the withdrawal of C767-Gal4 labeled structure is related to the formation of the fan-shaped body. Our result revealed the function of ten-a in central brain development, and possible cellular mechanism underlying Drosophila fan-shaped body formation.
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Phillips-Portillo J, Strausfeld NJ. Representation of the brain's superior protocerebrum of the flesh fly, Neobellieria bullata, in the central body. J Comp Neurol 2012; 520:3070-87. [PMID: 22434505 PMCID: PMC4876858 DOI: 10.1002/cne.23094] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The central complex of the insect brain is a system of midline neuropils involved in transforming sensory information into behavioral outputs. Genetic studies focusing on nerve cells supplying the central complex from the protocerebrum propose that such neurons play key roles in circuits involved in learning the distinction of visual cues during operant conditioning. To better identify the possible sites of such circuits we used Bodian and anti-synapsin staining to resolve divisions of the superior protocerebrum into discrete neuropils. Here we show that in the fly Neobellieria bullata, the superior protocerebrum is composed of at least five clearly defined regions that correspond to those identified in Drosophila melanogaster. Intracellular dye fills and Golgi impregnations resolve "tangential neurons" that have intricate systems of branches in two of these regions. The branches are elaborate, decorated with specializations indicative of pre- and postsynaptic sites. The tangentially arranged terminals of these neurons extend across characteristic levels of the central complex's fan-shaped body. In this and another blowfly species, we identify an asymmetric pair of neuropils situated deep in the fan-shaped body, called the asymmetric bodies because of their likely homology with similar elements in Drosophila. One of the pair of bodies receives collaterals from symmetric arrangements of tangential neuron terminals. Cobalt injections reveal that the superior protocerebrum is richly supplied with local interneurons that are likely participants in microcircuitry associated with the distal processes of tangential neurons. Understanding the morphologies and arrangements of these and other neurons is essential for correctly interpreting functional attributes of the central complex.
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Affiliation(s)
| | - Nicholas J. Strausfeld
- Department of Neuroscience, University of Arizona, Tucson, Arizona 85721
- Center for Insect Science University of Arizona, Tucson, Arizona 85721
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Distribution of metabotropic receptors of serotonin, dopamine, GABA, glutamate, and short neuropeptide F in the central complex of Drosophila. Neuroscience 2012; 208:11-26. [PMID: 22361394 DOI: 10.1016/j.neuroscience.2012.02.007] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2011] [Revised: 01/19/2012] [Accepted: 02/07/2012] [Indexed: 01/19/2023]
Abstract
The central complex is a prominent set of midline neuropils in the insect brain, known to be a higher locomotor control center that integrates visual inputs and modulates motor outputs. It is composed of four major neuropil structures, the ellipsoid body (EB), fan-shaped body (FB), noduli (NO), and protocerebral bridge (PB). In Drosophila different types of central complex neurons have been shown to express multiple neuropeptides and neurotransmitters; however, the distribution of corresponding receptors is not known. Here, we have mapped metabotropic, G-protein-coupled receptors (GPCRs) of several neurotransmitters to neurons of the central complex. By combining immunocytochemistry with GAL4 driven green fluorescent protein, we examined the distribution patterns of six different GPCRs: two serotonin receptor subtypes (5-HT(1B) and 5-HT(7)), a dopamine receptor (DopR), the metabotropic GABA(B) receptor (GABA(B)R), the metabotropic glutamate receptor (DmGluR(A)) and a short neuropeptide F receptor (sNPFR1). Five of the six GPCRs were mapped to different neurons in the EB (sNPFR1 was not seen). Different layers of the FB express DopR, GABA(B)R, DmGluR(A,) and sNPFR1, whereas only GABA(B)R and DmGluR(A) were localized to the PB. Finally, strong expression of DopR and DmGluR(A) was detected in the NO. In most cases the distribution patterns of the GPCRs matched the expression of markers for their respective ligands. In some nonmatching regions it is likely that other types of dopamine and serotonin receptors or ionotropic GABA and glutamate receptors are expressed. Our data suggest that chemical signaling and signal modulation are diverse and highly complex in the different compartments and circuits of the Drosophila central complex. The information provided here, on receptor distribution, will be very useful for future analysis of functional circuits in the central complex, based on targeted interference with receptor expression.
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Gong Z, Liu J, Guo C, Zhou Y, Teng Y, Liu L. Two Pairs of Neurons in the Central Brain Control Drosophila Innate Light Preference. Science 2010; 330:499-502. [DOI: 10.1126/science.1195993] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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25
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Young JM, Armstrong JD. Structure of the adult central complex in Drosophila: organization of distinct neuronal subsets. J Comp Neurol 2010; 518:1500-24. [PMID: 20187142 DOI: 10.1002/cne.22284] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
The central complex (CX) is a defined set of neuropils located on the midline of the protocerebrum in several arthropods and has been implicated in a number of behaviors. To investigate the function of the CX further it is imperative to know the neuroarchitecture of this structure and to ensure all known neuron types conform to a common nomenclature system. Several types of CX neuron have been identified but it is not known if these exist singly or as components of isomorphic sets. We used an enhancer trap approach to study the adult structure, connectivity, and polarity of CX neurons in Drosophila. We observed several isomorphic sets of small-field neurons including pontine and fb-eb neurons, and also isomorphic sets of large-field neurons including R neurons and F neurons. We found that several types of large-field F neurons existed in isomorphic sets of approximately eight (four per hemisphere) and found evidence for small-field neuron types existing as isomorphic sets of 16. Small-field neurons were observed in clearly organized layers. This study provides a novel insight into CX structure and connectivity and provides a set of characterized enhancer trap lines that will be valuable for future study.
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Affiliation(s)
- J M Young
- Institute for Adaptive and Neural Computation, University of Edinburgh, Edinburgh, UK.
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26
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Research progress on Drosophila visual cognition in China. SCIENCE CHINA-LIFE SCIENCES 2010; 53:374-384. [DOI: 10.1007/s11427-010-0073-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2009] [Accepted: 01/19/2010] [Indexed: 02/07/2023]
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27
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Nässel DR. Neuropeptide signaling near and far: how localized and timed is the action of neuropeptides in brain circuits? INVERTEBRATE NEUROSCIENCE 2009; 9:57-75. [PMID: 19756790 DOI: 10.1007/s10158-009-0090-1] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2009] [Accepted: 08/24/2009] [Indexed: 12/15/2022]
Abstract
Neuropeptide signaling is functionally very diverse and one and the same neuropeptide may act as a circulating neurohormone, as a locally released neuromodulator or even as a cotransmitter of classical fast-acting neurotransmitters. Thus, neuropeptides are produced by a huge variety of neuron types in different parts of the nervous system. Within the central nervous system (CNS) there are numerous types of peptidergic interneurons, some with strictly localized and patterned branching morphologies, others with widespread and diffuse arborizations. From morphology alone it is often difficult to predict the sphere of influence of a peptidergic interneuron, especially since it has been shown that neuropeptides can diffuse over tens of micrometers within neuropils, and that peptides probably are released exclusively in perisynaptic (or non-synaptic) regions. This review addresses some questions related to peptidergic signaling in the insect CNS. How diverse are the spatial relations between peptidergic neurons and their target neurons and what determines the sphere of functional influence? At one extreme there is volume transmission and at the other targeted cotransmission at synapses. Also temporal aspects of peptidergic signaling are of interest: how transient are peptidergic messages? Factors important for these spatial and temporal aspects of peptidergic signaling are proximity between release sites and cognate receptors, distribution of peptidase activity that can terminate peptide action and colocalization of other neuroactive compounds in the presynaptic peptidergic neuron (and corresponding receptors in target neurons). Other factors such as expression of different channel types, receptor inactivation mechanisms and second messenger systems probably also contribute to the diversity in temporal properties of peptide signaling.
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Affiliation(s)
- Dick R Nässel
- Department of Zoology, Stockholm University, 10691 Stockholm, Sweden.
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