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Mallick A, Tan HL, Epstein JM, Gaudry Q, Dacks AM. Serotonin acts through multiple cellular targets during an olfactory critical period. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.14.589413. [PMID: 38645269 PMCID: PMC11030346 DOI: 10.1101/2024.04.14.589413] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
Serotonin (5-HT) is known to modulate early development during critical periods when experience drives heightened levels of plasticity in neurons. Here, we take advantage of the genetically tractable olfactory system of Drosophila to investigate how 5-HT modulates critical period plasticity in the CO2 sensing circuit of fruit flies. Our study reveals that 5HT modulation of multiple neuronal targets is necessary for experience-dependent structural changes in an odor processing circuit. The olfactory CPP is known to involve local inhibitory networks and consistent with this we found that knocking down 5-HT7 receptors in a subset of GABAergic local interneurons was sufficient to block CPP, as was knocking down GABA receptors expressed by olfactory sensory neurons (OSNs). Additionally, direct modulation of OSNs via 5-HT2B expression in the cognate OSNs sensing CO2 is also essential for CPP. Furthermore, 5-HT1B expression by serotonergic neurons in the olfactory system is also required during the critical period. Our study reveals that 5-HT modulation of multiple neuronal targets is necessary for experience-dependent structural changes in an odor processing circuit.
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Affiliation(s)
- Ahana Mallick
- Department of Biology, University of Maryland, College Park, MD 20742, USA
| | - Hua Leonhard Tan
- Department of Biology, University of Maryland, College Park, MD 20742, USA
| | | | - Quentin Gaudry
- Department of Biology, University of Maryland, College Park, MD 20742, USA
- Senior Author: These authors contributed equally
| | - Andrew M Dacks
- Departments of Biology and Neuroscience, West Virginia University, Morgantown, WV 26505, USA
- Senior Author: These authors contributed equally
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Mallick A, Dacks AM, Gaudry Q. Olfactory Critical Periods: How Odor Exposure Shapes the Developing Brain in Mice and Flies. BIOLOGY 2024; 13:94. [PMID: 38392312 PMCID: PMC10886215 DOI: 10.3390/biology13020094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2023] [Revised: 01/26/2024] [Accepted: 01/30/2024] [Indexed: 02/24/2024]
Abstract
Neural networks have an extensive ability to change in response to environmental stimuli. This flexibility peaks during restricted windows of time early in life called critical periods. The ubiquitous occurrence of this form of plasticity across sensory modalities and phyla speaks to the importance of critical periods for proper neural development and function. Extensive investigation into visual critical periods has advanced our knowledge of the molecular events and key processes that underlie the impact of early-life experience on neuronal plasticity. However, despite the importance of olfaction for the overall survival of an organism, the cellular and molecular basis of olfactory critical periods have not garnered extensive study compared to visual critical periods. Recent work providing a comprehensive mapping of the highly organized olfactory neuropil and its development has in turn attracted a growing interest in how these circuits undergo plasticity during critical periods. Here, we perform a comparative review of olfactory critical periods in fruit flies and mice to provide novel insight into the importance of early odor exposure in shaping neural circuits and highlighting mechanisms found across sensory modalities.
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Affiliation(s)
- Ahana Mallick
- Department of Biology, University of Maryland, College Park, MD 20742, USA
| | - Andrew M Dacks
- Department of Biology, West Virginia University, Morgantown, WV 26505, USA
| | - Quentin Gaudry
- Department of Biology, University of Maryland, College Park, MD 20742, USA
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3
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Suyama R, Cetraro N, Yew JY, Kai T. Microbes control Drosophila germline stem cell increase and egg maturation through hormonal pathways. Commun Biol 2023; 6:1287. [PMID: 38123715 PMCID: PMC10733356 DOI: 10.1038/s42003-023-05660-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Accepted: 12/01/2023] [Indexed: 12/23/2023] Open
Abstract
Reproduction is highly dependent on environmental and physiological factors including nutrition, mating stimuli and microbes. Among these factors, microbes facilitate vital functions for host animals such as nutritional intake, metabolic regulation, and enhancing fertility under poor nutrition conditions. However, detailed molecular mechanisms by which microbes control germline maturation, leading to reproduction, remain largely unknown. In this study, we show that environmental microbes exert a beneficial effect on Drosophila oogenesis by promoting germline stem cell (GSC) proliferation and subsequent egg maturation via acceleration of ovarian cell division and suppression of apoptosis. Moreover, insulin-related signaling is not required; rather, the ecdysone pathway is necessary for microbe-induced increase of GSCs and promotion of egg maturation, while juvenile hormone contributes only to increasing GSC numbers, suggesting that hormonal pathways are activated at different stages of oogenesis. Our findings reveal that environmental microbes can enhance host reproductivity by modulating host hormone release and promoting oogenesis.
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Affiliation(s)
- Ritsuko Suyama
- Laboratory of Germline Biology, Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka Suita, Osaka, 565-0871, Japan.
| | - Nicolas Cetraro
- Pacific Biosciences Research Center, University of Hawai'i at Manoa, 1993 East-West Road, Honolulu, HI, 96822, USA
| | - Joanne Y Yew
- Pacific Biosciences Research Center, University of Hawai'i at Manoa, 1993 East-West Road, Honolulu, HI, 96822, USA.
| | - Toshie Kai
- Laboratory of Germline Biology, Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka Suita, Osaka, 565-0871, Japan.
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Martin M, Gutierrez-Avino F, Shaikh MN, Tejedor FJ. A novel proneural function of Asense is integrated with the sequential actions of Delta-Notch, L'sc and Su(H) to promote the neuroepithelial to neuroblast transition. PLoS Genet 2023; 19:e1010991. [PMID: 37871020 PMCID: PMC10621995 DOI: 10.1371/journal.pgen.1010991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Revised: 11/02/2023] [Accepted: 09/20/2023] [Indexed: 10/25/2023] Open
Abstract
In order for neural progenitors (NPs) to generate distinct populations of neurons at the right time and place during CNS development, they must switch from undergoing purely proliferative, self-renewing divisions to neurogenic, asymmetric divisions in a tightly regulated manner. In the developing Drosophila optic lobe, neuroepithelial (NE) cells of the outer proliferation center (OPC) are progressively transformed into neurogenic NPs called neuroblasts (NBs) in a medial to lateral proneural wave. The cells undergoing this transition express Lethal of Scute (L'sc), a proneural transcription factor (TF) of the Acheate Scute Complex (AS-C). Here we show that there is also a peak of expression of Asense (Ase), another AS-C TF, in the cells neighboring those with transient L'sc expression. These peak of Ase cells help to identify a new transitional stage as they have lost NE markers and L'sc, they receive a strong Notch signal and barely exhibit NB markers. This expression of Ase is necessary and sufficient to promote the NE to NB transition in a more robust and rapid manner than that of l'sc gain of function or Notch loss of function. Thus, to our knowledge, these data provide the first direct evidence of a proneural role for Ase in CNS neurogenesis. Strikingly, we found that strong Delta-Notch signaling at the lateral border of the NE triggers l'sc expression, which in turn induces ase expression in the adjacent cells through the activation of Delta-Notch signaling. These results reveal two novel non-conventional actions of Notch signaling in driving the expression of proneural factors, in contrast to the repression that Notch signaling exerts on them during classical lateral inhibition. Finally, Suppressor of Hairless (Su(H)), which seems to be upregulated late in the transitioning cells and in NBs, represses l'sc and ase, ensuring their expression is transient. Thus, our data identify a key proneural role of Ase that is integrated with the sequential activities of Delta-Notch signaling, L'sc, and Su(H), driving the progressive transformation of NE cells into NBs.
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Affiliation(s)
- Mercedes Martin
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas and Universidad Miguel Hernandez, Sant Joan d’Alacant, Spain
| | - Francisco Gutierrez-Avino
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas and Universidad Miguel Hernandez, Sant Joan d’Alacant, Spain
| | - Mirja N. Shaikh
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas and Universidad Miguel Hernandez, Sant Joan d’Alacant, Spain
| | - Francisco J. Tejedor
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas and Universidad Miguel Hernandez, Sant Joan d’Alacant, Spain
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Jain CK, Bhargava S, Jain I, Varshney S. Targeting Notch Pathway in Cancer Diagnostics and Therapeutics: An Emerging Approach. Recent Pat Anticancer Drug Discov 2021; 17:244-252. [PMID: 34109915 DOI: 10.2174/1574892816666210607092350] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 12/28/2020] [Accepted: 10/14/2021] [Indexed: 11/22/2022]
Abstract
The Notch signaling pathway is an evolutionarily conserved pathway usually present in multicellular organisms, which plays a pivotal role in cell fate determination and proliferation. Due to this property, it is highly oncogenic, especially in the dysregulated version of the Notch pathway, where apoptosis is inhibited, and abnormal cell growth is supported. Notch receptors and ligand proteins play an essential role in cancers, for instance, myeloid leukemia, T-cell lymphoblastic leukemia, and organ-specific, i.e., breast, colon, pancreas, and skin cancers. Any type of cancer generates as a result of genetic defects, including epigenetic alterations as well as mutations. These alterations can be used by the researchers to find a promising diagnostic as well as therapeutic tool for cancer. The successful inhibition of the Notch pathway with the help of specific biomarkers or suppression of gene expression represents a new remedy in the field of cancer research. This article focuses on the various remedies hidden within the Notch pathway's mechanism, primarily based on different patents published in recent years for assisting cancer diagnosis and succeeding treatment.
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Affiliation(s)
- Chakresh Kumar Jain
- Department of Biotechnology, Jaypee Institute of Information Technology, A-10, Sector -62 NOIDA Uttar Pradesh, India
| | - Shreya Bhargava
- Department of Biotechnology, Jaypee Institute of Information Technology, A-10, Sector -62 NOIDA Uttar Pradesh, India
| | - Isha Jain
- Department of Biotechnology, Jaypee Institute of Information Technology, A-10, Sector -62 NOIDA Uttar Pradesh, India
| | - Srishti Varshney
- Department of Biotechnology, Jaypee Institute of Information Technology, A-10, Sector -62 NOIDA Uttar Pradesh, India
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Salazar JL, Yang SA, Yamamoto S. Post-Developmental Roles of Notch Signaling in the Nervous System. Biomolecules 2020; 10:biom10070985. [PMID: 32630239 PMCID: PMC7408554 DOI: 10.3390/biom10070985] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 06/25/2020] [Accepted: 06/26/2020] [Indexed: 12/14/2022] Open
Abstract
Since its discovery in Drosophila, the Notch signaling pathway has been studied in numerous developmental contexts in diverse multicellular organisms. The role of Notch signaling in nervous system development has been extensively investigated by numerous scientists, partially because many of the core Notch signaling components were initially identified through their dramatic ‘neurogenic’ phenotype of developing fruit fly embryos. Components of the Notch signaling pathway continue to be expressed in mature neurons and glia cells, which is suggestive of a role in the post-developmental nervous system. The Notch pathway has been, so far, implicated in learning and memory, social behavior, addiction, and other complex behaviors using genetic model organisms including Drosophila and mice. Additionally, Notch signaling has been shown to play a modulatory role in several neurodegenerative disease model animals and in mediating neural toxicity of several environmental factors. In this paper, we summarize the knowledge pertaining to the post-developmental roles of Notch signaling in the nervous system with a focus on discoveries made using the fruit fly as a model system as well as relevant studies in C elegans, mouse, rat, and cellular models. Since components of this pathway have been implicated in the pathogenesis of numerous psychiatric and neurodegenerative disorders in human, understanding the role of Notch signaling in the mature brain using model organisms will likely provide novel insights into the mechanisms underlying these diseases.
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Affiliation(s)
- Jose L. Salazar
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; (J.L.S.); (S.-A.Y.)
| | - Sheng-An Yang
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; (J.L.S.); (S.-A.Y.)
| | - Shinya Yamamoto
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX 77030, USA; (J.L.S.); (S.-A.Y.)
- Department of Neuroscience, BCM, Houston, TX 77030, USA
- Program in Developmental Biology, BCM, Houston, TX 77030, USA
- Development, Disease Models & Therapeutics Graduate Program, BCM, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX 77030, USA
- Correspondence: ; Tel.: +1-832-824-8119
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7
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Glomerulus-Selective Regulation of a Critical Period for Interneuron Plasticity in the Drosophila Antennal Lobe. J Neurosci 2020; 40:5549-5560. [PMID: 32532889 PMCID: PMC7363474 DOI: 10.1523/jneurosci.2192-19.2020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Revised: 05/30/2020] [Accepted: 06/02/2020] [Indexed: 11/21/2022] Open
Abstract
Several features of the adult nervous systems develop in a "critical period" (CP), during which high levels of plasticity allow neural circuits to be tuned for optimal performance. Through an analysis of long-term olfactory habituation (LTH) in female Drosophila, we provide new insight into mechanisms by which CPs are regulated in vivo LTH manifests as a persistently reduced behavioral response to an odorant encountered for 4 continuous days and occurs together with the growth of specific, odorant-responsive glomeruli in the antennal lobe. We show that the CP for behavioral and structural plasticity induced by ethyl butyrate (EB) or carbon dioxide (CO2) closes within 48 h after eclosion. The elaboration of excitatory projection neuron (PN) processes likely contribute to glomerular volume increases, as follows: both occur together and similarly require cAMP signaling in the antennal lobe inhibitory local interneurons. Further, the CP for structural plasticity could be extended beyond 48 h if EB- or CO2-responsive olfactory sensory neurons (OSNs) are silenced after eclosion; thus, OSN activity is required for closing the CP. Strikingly, silencing of glomerulus-selective OSNs extends the CP for structural plasticity only in respective target glomeruli. This indicates the existence of a local, short-range mechanism for regulating CP closure. Such a local mechanism for CP regulation can explain why plasticity induced by the odorant geranyl acetate (which is attractive) shows no CP although it involves the same core plasticity mechanisms as CO2 and EB. Local control of closure mechanisms during the critical period can potentially impart evolutionarily adaptive, odorant-specific features to behavioral plasticity.SIGNIFICANCE STATEMENT The critical period for plasticity represents a stage of life at which animals learn specific tasks or features with particular facility. This work provides fresh evidence that mechanisms for regulating critical periods are broadly conserved across evolution. Thus, a critical period for long-term olfactory habituation in Drosophila, which closes early in adulthood can, like the critical period for ocular dominance plasticity in mammals, be extended by blocking sensory neurons early in life. Further observations show that critical periods for plasticity can be regulated by spatially restricted mechanisms, potentially allowing varied critical periods for plasticity to stimuli of different ethological relevance.
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8
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Harris RE, Stinchfield MJ, Nystrom SL, McKay DJ, Hariharan IK. Damage-responsive, maturity-silenced enhancers regulate multiple genes that direct regeneration in Drosophila. eLife 2020; 9:58305. [PMID: 32490812 PMCID: PMC7299344 DOI: 10.7554/elife.58305] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 05/28/2020] [Indexed: 12/31/2022] Open
Abstract
Like tissues of many organisms, Drosophila imaginal discs lose the ability to regenerate as they mature. This loss of regenerative capacity coincides with reduced damage-responsive expression of multiple genes needed for regeneration. We previously showed that two such genes, wg and Wnt6, are regulated by a single damage-responsive enhancer that becomes progressively inactivated via Polycomb-mediated silencing as discs mature (Harris et al., 2016). Here we explore the generality of this mechanism and identify additional damage-responsive, maturity-silenced (DRMS) enhancers, some near genes known to be required for regeneration such as Mmp1, and others near genes that we now show function in regeneration. Using a novel GAL4-independent ablation system we characterize two DRMS-associated genes, apontic (apt), which curtails regeneration and CG9752/asperous (aspr), which promotes it. This mechanism of suppressing regeneration by silencing damage-responsive enhancers at multiple loci can be partially overcome by reducing activity of the chromatin regulator extra sex combs (esc).
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Affiliation(s)
| | | | - Spencer L Nystrom
- University of North Carolina at Chapel Hill, Chapel Hill, United States
| | - Daniel J McKay
- University of North Carolina at Chapel Hill, Chapel Hill, United States
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9
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Ho DM, Artavanis-Tsakonas S, Louvi A. The Notch pathway in CNS homeostasis and neurodegeneration. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2019; 9:e358. [PMID: 31502763 DOI: 10.1002/wdev.358] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 06/19/2019] [Accepted: 06/23/2019] [Indexed: 12/19/2022]
Abstract
The role of the Notch signaling pathway in neural development has been well established over many years. More recent studies, however, have demonstrated that Notch continues to be expressed and active throughout adulthood in many areas of the central nervous system. Notch signals have been implicated in adult neurogenesis, memory formation, and synaptic plasticity in the adult organism, as well as linked to acute brain trauma and chronic neurodegenerative conditions. NOTCH3 mutations are responsible for the most common form of hereditary stroke, the progressive disorder cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy. Notch has also been associated with several progressive neurodegenerative diseases, including Alzheimer's disease, multiple sclerosis, and amyotrophic lateral sclerosis. Although numerous studies link Notch activity with CNS homeostasis and neurodegenerative diseases, the data thus far are primarily correlative, rather than functional. Nevertheless, the evidence for Notch pathway activity in specific neural cellular contexts is strong, and certainly intriguing, and points to the possibility that the pathway carries therapeutic promise. This article is categorized under: Nervous System Development > Flies Signaling Pathways > Cell Fate Signaling Nervous System Development > Vertebrates: General Principles.
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Affiliation(s)
- Diana M Ho
- Department of Cell Biology, Harvard Medical School, Boston, Massachusetts
| | | | - Angeliki Louvi
- Departments of Neurosurgery and Neuroscience and Program on Neurogenetics, Yale School of Medicine, New Haven, Connecticut
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10
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Activity-Dependent Remodeling of Drosophila Olfactory Sensory Neuron Brain Innervation during an Early-Life Critical Period. J Neurosci 2019; 39:2995-3012. [PMID: 30755492 DOI: 10.1523/jneurosci.2223-18.2019] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 01/07/2019] [Accepted: 02/03/2019] [Indexed: 12/12/2022] Open
Abstract
Critical periods are windows of development when the environment has a pronounced effect on brain circuitry. Models of neurodevelopmental disorders, including autism spectrum disorders, intellectual disabilities, and schizophrenia, are linked to disruption of critical period remodeling. Critical periods open with the onset of sensory experience; however, it remains unclear exactly how sensory input modifies brain circuits. Here, we examine olfactory sensory neuron (OSN) innervation of the Drosophila antennal lobe of both sexes as a genetic model of this question. We find that olfactory sensory experience during an early-use critical period drives loss of OSN innervation of antennal lobe glomeruli and subsequent axon retraction in a dose-dependent mechanism. This remodeling does not result from olfactory receptor loss or OSN degeneration, but rather from rapid synapse elimination and axon pruning in the target olfactory glomerulus. Removal of the odorant stimulus only during the critical period leads to OSN reinnervation, demonstrating that remodeling is transiently reversible. We find that this synaptic refinement requires the OSN-specific olfactory receptor and downstream activity. Conversely, blocking OSN synaptic output elevates glomeruli remodeling. We find that GABAergic neurotransmission has no detectable role, but that glutamatergic signaling via NMDA receptors is required for OSN synaptic refinement. Together, these results demonstrate that OSN inputs into the brain manifest robust, experience-dependent remodeling during an early-life critical period, which requires olfactory reception, OSN activity, and NMDA receptor signaling. This work reveals a pathway linking initial olfactory sensory experience to glutamatergic neurotransmission in the activity-dependent remodeling of brain neural circuitry in an early-use critical period.SIGNIFICANCE STATEMENT Neurodevelopmental disorders manifest symptoms at specific developmental milestones that suggest an intersection between early sensory experience and brain neural circuit remodeling. One classic example is Fragile X syndrome caused by loss of an RNA-binding translation regulator of activity-dependent synaptic refinement. As a model, Drosophila olfactory circuitry is well characterized, genetically tractable, and rapidly developing, and thus ideally suited to probe underlying mechanisms. Here, we find olfactory sensory neurons are dramatically remodeled by heightened sensory experience during an early-life critical period. We demonstrate removing the olfactory stimulus during the critical period can reverse the connectivity changes. We find that this remodeling requires neural activity and NMDA receptor-mediated glutamatergic transmission. This improved understanding may help us design treatments for neurodevelopmental disorders.
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11
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Slankster E, Odell SR, Mathew D. Strength in diversity: functional diversity among olfactory neurons of the same type. J Bioenerg Biomembr 2019; 51:65-75. [PMID: 30604088 PMCID: PMC6382560 DOI: 10.1007/s10863-018-9779-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 11/13/2018] [Indexed: 01/01/2023]
Abstract
Most animals depend upon olfaction to find food, mates, and to avoid predators. An animal's olfactory circuit helps it sense its olfactory environment and generate critical behavioral responses. The general architecture of the olfactory circuit, which is conserved across species, is made up of a few different neuronal types including first-order receptor neurons, second- and third-order neurons, and local interneurons. Each neuronal type differs in their morphology, physiology, and neurochemistry. However, several recent studies have suggested that there is intrinsic diversity even among neurons of the same type and that this diversity is important for neural function. In this review, we first examine instances of intrinsic diversity observed among individual types of olfactory neurons. Next, we review potential genetic and experience-based plasticity mechanisms that underlie this diversity. Finally, we consider the implications of intrinsic neuronal diversity for circuit function. Overall, we hope to highlight the importance of intrinsic diversity as a previously underestimated property of circuit function.
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Affiliation(s)
- Eryn Slankster
- Department of Biology, University of Nevada, 1664 N. Virginia St., MS: 0314, Reno, NV, 89557, USA
| | - Seth R Odell
- Department of Biology, University of Nevada, 1664 N. Virginia St., MS: 0314, Reno, NV, 89557, USA
- Integrated Neuroscience Program, University of Nevada, Reno, NV, 89557, USA
| | - Dennis Mathew
- Department of Biology, University of Nevada, 1664 N. Virginia St., MS: 0314, Reno, NV, 89557, USA.
- Integrated Neuroscience Program, University of Nevada, Reno, NV, 89557, USA.
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12
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Petruccelli E, Feyder M, Ledru N, Jaques Y, Anderson E, Kaun KR. Alcohol Activates Scabrous-Notch to Influence Associated Memories. Neuron 2018; 100:1209-1223.e4. [PMID: 30482693 DOI: 10.1016/j.neuron.2018.10.005] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Revised: 08/17/2018] [Accepted: 10/02/2018] [Indexed: 12/17/2022]
Abstract
Drugs of abuse, like alcohol, modulate gene expression in reward circuits and consequently alter behavior. However, the in vivo cellular mechanisms through which alcohol induces lasting transcriptional changes are unclear. We show that Drosophila Notch/Su(H) signaling and the secreted fibrinogen-related protein Scabrous in mushroom body (MB) memory circuitry are important for the enduring preference of cues associated with alcohol's rewarding properties. Alcohol exposure affects Notch responsivity in the adult MB and alters Su(H) targeting at the dopamine-2-like receptor (Dop2R). Alcohol cue training also caused lasting changes to the MB nuclear transcriptome, including changes in the alternative splicing of Dop2R and newly implicated transcripts like Stat92E. Together, our data suggest that alcohol-induced activation of the highly conserved Notch pathway and accompanying transcriptional responses in memory circuitry contribute to addiction. Ultimately, this provides mechanistic insight into the etiology and pathophysiology of alcohol use disorder.
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Affiliation(s)
- Emily Petruccelli
- Department of Neuroscience, Brown University, Providence, RI 02912, USA
| | - Michael Feyder
- Department of Neuroscience, Brown University, Providence, RI 02912, USA
| | - Nicolas Ledru
- Department of Neuroscience, Brown University, Providence, RI 02912, USA
| | - Yanabah Jaques
- Department of Neuroscience, Brown University, Providence, RI 02912, USA
| | - Edward Anderson
- Department of Neuroscience, Brown University, Providence, RI 02912, USA
| | - Karla R Kaun
- Department of Neuroscience, Brown University, Providence, RI 02912, USA.
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13
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LIN-12/Notch Regulates GABA Signaling at the Caenorhabditis elegans Neuromuscular Junction. G3-GENES GENOMES GENETICS 2018; 8:2825-2832. [PMID: 29950427 PMCID: PMC6071610 DOI: 10.1534/g3.118.200202] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The role of Notch signaling in cell-fate decisions has been studied extensively; however, this pathway is also active in adult tissues, including the nervous system. Notch signaling modulates a wide range of behaviors and processes of the nervous system in the nematode Caenorhabditis elegans, but there is no evidence for Notch signaling directly altering synaptic strength. Here, we demonstrate Notch-mediated regulation of synaptic activity at the C. elegans neuromuscular junction (NMJ). For this, we used aldicarb, an inhibitor of the enzyme acetylcholinesterase, and assessed paralysis rates of animals with altered Notch signaling. Notch receptors LIN-12 and GLP-1 are required for normal NMJ function; they regulate NMJ activity in an opposing fashion. Complete loss of LIN-12 skews the excitation/inhibition balance at the NMJ toward increased activity, whereas partial loss of GLP-1 has the opposite effect. Specific Notch ligands and co-ligands are also required for proper NMJ function. The role of LIN-12 is independent of cell-fate decisions; manipulation of LIN-12 signaling through RNAi knockdown or overexpression of the co-ligand OSM-11 after development alters NMJ activity. We demonstrate that LIN-12 modulates GABA signaling in this paradigm, as loss of GABA signaling suppresses LIN-12 gain-of-function defects. Further analysis, in vivo and in silico, suggests that LIN-12 may modulate transcription of the GABAB receptor GBB-2 Our findings confirm a non-developmental role for the LIN-12/Notch receptor in regulating synaptic signaling and identify the GABAB receptor GBB-2 as a potential Notch transcriptional target in the C. elegans nervous system.
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14
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Liou NF, Lin SH, Chen YJ, Tsai KT, Yang CJ, Lin TY, Wu TH, Lin HJ, Chen YT, Gohl DM, Silies M, Chou YH. Diverse populations of local interneurons integrate into the Drosophila adult olfactory circuit. Nat Commun 2018; 9:2232. [PMID: 29884811 PMCID: PMC5993751 DOI: 10.1038/s41467-018-04675-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 05/14/2018] [Indexed: 11/09/2022] Open
Abstract
Drosophila olfactory local interneurons (LNs) in the antennal lobe are highly diverse and variable. How and when distinct types of LNs emerge, differentiate, and integrate into the olfactory circuit is unknown. Through systematic developmental analyses, we found that LNs are recruited to the adult olfactory circuit in three groups. Group 1 LNs are residual larval LNs. Group 2 are adult-specific LNs that emerge before cognate sensory and projection neurons establish synaptic specificity, and Group 3 LNs emerge after synaptic specificity is established. Group 1 larval LNs are selectively reintegrated into the adult circuit through pruning and re-extension of processes to distinct regions of the antennal lobe, while others die during metamorphosis. Precise temporal control of this pruning and cell death shapes the global organization of the adult antennal lobe. Our findings provide a road map to understand how LNs develop and contribute to constructing the olfactory circuit. Local interneurons (LNs) in the Drosophila olfactory system are highly diverse. Here, the authors labeled different LN types and described how different LN subtypes are integrated into the developing circuit.
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Affiliation(s)
- Nan-Fu Liou
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Shih-Han Lin
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Ying-Jun Chen
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Kuo-Ting Tsai
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Chi-Jen Yang
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Tzi-Yang Lin
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 11529, Taiwan.,Research Institute of Molecular Pathology (IMP), Vienna Biocenter, Campus-Vienna-Biocenter 1, 1030, Vienna, Austria
| | - Ting-Han Wu
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Hsin-Ju Lin
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Yuh-Tarng Chen
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Daryl M Gohl
- Department of Neurobiology, Stanford University, Stanford, CA, 94305, USA.,University of Minnesota Genomics Center, 1-210 CCRB, 2231 6th Street SE, Minneapolis, MN, 55455, USA
| | - Marion Silies
- Department of Neurobiology, Stanford University, Stanford, CA, 94305, USA.,European Neuroscience Institute, University Medical Center Göttingen, Grisebachstr. 5, 37077, Göttingen, Germany
| | - Ya-Hui Chou
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 11529, Taiwan. .,Neuroscience Program of Academia Sinica, Academia Sinica, Taipei, 11529, Taiwan.
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15
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Salazar JL, Yamamoto S. Integration of Drosophila and Human Genetics to Understand Notch Signaling Related Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1066:141-185. [PMID: 30030826 PMCID: PMC6233323 DOI: 10.1007/978-3-319-89512-3_8] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Notch signaling research dates back to more than one hundred years, beginning with the identification of the Notch mutant in the fruit fly Drosophila melanogaster. Since then, research on Notch and related genes in flies has laid the foundation of what we now know as the Notch signaling pathway. In the 1990s, basic biological and biochemical studies of Notch signaling components in mammalian systems, as well as identification of rare mutations in Notch signaling pathway genes in human patients with rare Mendelian diseases or cancer, increased the significance of this pathway in human biology and medicine. In the 21st century, Drosophila and other genetic model organisms continue to play a leading role in understanding basic Notch biology. Furthermore, these model organisms can be used in a translational manner to study underlying mechanisms of Notch-related human diseases and to investigate the function of novel disease associated genes and variants. In this chapter, we first briefly review the major contributions of Drosophila to Notch signaling research, discussing the similarities and differences between the fly and human pathways. Next, we introduce several biological contexts in Drosophila in which Notch signaling has been extensively characterized. Finally, we discuss a number of genetic diseases caused by mutations in genes in the Notch signaling pathway in humans and we expand on how Drosophila can be used to study rare genetic variants associated with these and novel disorders. By combining modern genomics and state-of-the art technologies, Drosophila research is continuing to reveal exciting biology that sheds light onto mechanisms of disease.
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Affiliation(s)
- Jose L Salazar
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX, USA
| | - Shinya Yamamoto
- Department of Molecular and Human Genetics, Baylor College of Medicine (BCM), Houston, TX, USA.
- Program in Developmental Biology, BCM, Houston, TX, USA.
- Department of Neuroscience, BCM, Houston, TX, USA.
- Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX, USA.
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16
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Pekar O, Ow MC, Hui KY, Noyes MB, Hall SE, Hubbard EJA. Linking the environment, DAF-7/TGFβ signaling and LAG-2/DSL ligand expression in the germline stem cell niche. Development 2017; 144:2896-2906. [PMID: 28811311 DOI: 10.1242/dev.147660] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2016] [Accepted: 07/01/2017] [Indexed: 02/04/2023]
Abstract
The developmental accumulation of proliferative germ cells in the C. elegans hermaphrodite is sensitive to the organismal environment. Previously, we found that the TGFβ signaling pathway links the environment and proliferative germ cell accumulation. Neuronal DAF-7/TGFβ causes a DAF-1/TGFβR signaling cascade in the gonadal distal tip cell (DTC), the germline stem cell niche, where it negatively regulates a DAF-3 SMAD and DAF-5 Sno-Ski. LAG-2, a founding DSL ligand family member, is produced in the DTC and activates the GLP-1/Notch receptor on adjacent germ cells to maintain germline stem cell fate. Here, we show that DAF-7/TGFβ signaling promotes expression of lag-2 in the DTC in a daf-3-dependent manner. Using ChIP and one-hybrid assays, we find evidence for direct interaction between DAF-3 and the lag-2 promoter. We further identify a 25 bp DAF-3 binding element required for the DTC lag-2 reporter response to the environment and to DAF-7/TGFβ signaling. Our results implicate DAF-3 repressor complex activity as a key molecular mechanism whereby the environment influences DSL ligand expression in the niche to modulate developmental expansion of the germline stem cell pool.
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Affiliation(s)
- Olga Pekar
- Skirball Institute of Biomolecular Medicine and Department of Cell Biology, NYU School of Medicine, New York, NY 10016, USA
| | - Maria C Ow
- Department of Biology, Syracuse University, Syracuse, NY 13244, USA
| | - Kailyn Y Hui
- Institute for Systems Genetics, NYU School of Medicine, New York, NY 10016, USA
| | - Marcus B Noyes
- Institute for Systems Genetics, NYU School of Medicine, New York, NY 10016, USA
| | - Sarah E Hall
- Department of Biology, Syracuse University, Syracuse, NY 13244, USA
| | - E Jane Albert Hubbard
- Skirball Institute of Biomolecular Medicine and Department of Cell Biology, NYU School of Medicine, New York, NY 10016, USA
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17
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Strube-Bloss MF, Grabe V, Hansson BS, Sachse S. Calcium imaging revealed no modulatory effect on odor-evoked responses of the Drosophila antennal lobe by two populations of inhibitory local interneurons. Sci Rep 2017; 7:7854. [PMID: 28798324 PMCID: PMC5552818 DOI: 10.1038/s41598-017-08090-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Accepted: 07/06/2017] [Indexed: 12/26/2022] Open
Abstract
Although we have considerable knowledge about how odors are represented in the antennal lobe (AL), the insects’ analogue to the olfactory bulb, we still do not fully understand how the different neurons in the AL network contribute to the olfactory code. In Drosophila melanogaster we can selectively manipulate specific neuronal populations to elucidate their function in odor processing. Here we silenced the synaptic transmission of two distinct subpopulations of multiglomerular GABAergic local interneurons (LN1 and LN2) using shibire (shits) and analyzed their impact on odor-induced glomerular activity at the AL input and output level. We verified that the employed shits construct effectively blocked synaptic transmission to the AL when expressed in olfactory sensory neurons. Notably, selective silencing of both LN populations did not significantly affect the odor-evoked activity patterns in the AL. Neither the glomerular input nor the glomerular output activity was modulated in comparison to the parental controls. We therefore conclude that these LN subpopulations, which cover one third of the total LN number, are not predominantly involved in odor identity coding per se. As suggested by their broad innervation patterns and contribution to long-term adaptation, they might contribute to AL–computation on a global and longer time scale.
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Affiliation(s)
- Martin F Strube-Bloss
- Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Hans-Knöll-Straße 8, 07745, Jena, Germany.,Department of Behavioral Physiology & Sociobiology, Theodor-Boveri-Institute of Bioscience, Biocenter University of Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Veit Grabe
- Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Hans-Knöll-Straße 8, 07745, Jena, Germany
| | - Bill S Hansson
- Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Hans-Knöll-Straße 8, 07745, Jena, Germany
| | - Silke Sachse
- Max Planck Institute for Chemical Ecology, Department of Evolutionary Neuroethology, Hans-Knöll-Straße 8, 07745, Jena, Germany.
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18
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Kim K, Kim JH, Kim YH, Hong SE, Lee SH. Pathway profiles based on gene-set enrichment analysis in the honey bee Apis mellifera under brood rearing-suppressed conditions. Genomics 2017; 110:43-49. [PMID: 28803879 DOI: 10.1016/j.ygeno.2017.08.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 07/25/2017] [Accepted: 08/09/2017] [Indexed: 11/29/2022]
Abstract
Perturbation of normal behaviors in honey bee colonies by any external factor can immediately reduce the colony's capacity for brood rearing, which can eventually lead to colony collapse. To investigate the effects of brood-rearing suppression on the biology of honey bee workers, gene-set enrichment analysis of the transcriptomes of worker bees with or without suppressed brood rearing was performed. When brood rearing was suppressed, pathways associated with both protein degradation and synthesis were simultaneously over-represented in both nurses and foragers, and their overall pathway representation profiles resembled those of normal foragers and nurses, respectively. Thus, obstruction of normal labor induced over-representation in pathways related with reshaping of worker bee physiology, suggesting that transition of labor is physiologically reversible. In addition, some genes associated with the regulation of neuronal excitability, cellular and nutritional stress and aggressiveness were over-expressed under brood rearing suppression perhaps to manage in-hive stress under unfavorable conditions.
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Affiliation(s)
- Kyungmun Kim
- Department of Agricultural Biotechnology, Seoul National University, Seoul 151-921, Republic of Korea
| | - Ju Hyeon Kim
- Department of Agricultural Biotechnology, Seoul National University, Seoul 151-921, Republic of Korea
| | - Young Ho Kim
- Department of Applied Biology, College of Ecology & Environmental Science, Kyungpook National University, Sangju, Gyeongbuk, Republic of Korea
| | - Seong-Eui Hong
- Theragen Etex, Bio Institute, Suwon, Gyeonggi-do, Republic of Korea
| | - Si Hyeock Lee
- Department of Agricultural Biotechnology, Seoul National University, Seoul 151-921, Republic of Korea; Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul, Republic of Korea.
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19
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Development of an optimized synthetic Notch receptor as an in vivo cell-cell contact sensor. Proc Natl Acad Sci U S A 2017; 114:5467-5472. [PMID: 28490499 DOI: 10.1073/pnas.1703205114] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Detection and manipulation of direct cell-cell contact in complex tissues is a fundamental and challenging problem in many biological studies. Here, we report an optimized Notch-based synthetic receptor (synNQ) useful to study direct cell-cell interactions in Drosophila With the synNQ system, cells expressing a synthetic receptor, which contains Notch activation machinery and a downstream transcriptional activator, QF, are activated by a synthetic GFP ligand expressed by contacting neighbor cells. To avoid cis-inhibition, mutually exclusive expression of the synthetic ligand and receptor is achieved using the "flippase-out" system. Expression of the synthetic GFP ligand is controlled by the Gal4/UAS system for easy and broad applications. Using synNQ, we successfully visualized cell-cell interactions within and between most fly tissues, revealing previously undocumented cell-cell contacts. Importantly, in addition to detection of cells in contact with one another, synNQ allows for genetic manipulation in all cells in contact with a targeted cell population, which we demonstrate in the context of cell competition in developing wing disks. Altogether, the synNQ genetic system will enable a broad range of studies of cell contact in developmental biology.
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20
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Weinberger S, Topping MP, Yan J, Claeys A, Geest ND, Ozbay D, Hassan T, He X, Albert JT, Hassan BA, Ramaekers A. Evolutionary changes in transcription factor coding sequence quantitatively alter sensory organ development and function. eLife 2017; 6. [PMID: 28406397 PMCID: PMC5432213 DOI: 10.7554/elife.26402] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 03/27/2017] [Indexed: 11/16/2022] Open
Abstract
Animals are characterized by a set of highly conserved developmental regulators. Changes in the cis-regulatory elements of these regulators are thought to constitute the major driver of morphological evolution. However, the role of coding sequence evolution remains unresolved. To address this question, we used the Atonal family of proneural transcription factors as a model. Drosophila atonal coding sequence was endogenously replaced with that of atonal homologues (ATHs) at key phylogenetic positions, non-ATH proneural genes, and the closest homologue to ancestral proneural genes. ATHs and the ancestral-like coding sequences rescued sensory organ fate in atonal mutants, in contrast to non-ATHs. Surprisingly, different ATH factors displayed different levels of proneural activity as reflected by the number and functionality of sense organs. This proneural potency gradient correlated directly with ATH protein stability, including in response to Notch signaling, independently of mRNA levels or codon usage. This establishes a distinct and ancient function for ATHs and demonstrates that coding sequence evolution can underlie quantitative variation in sensory development and function. DOI:http://dx.doi.org/10.7554/eLife.26402.001
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Affiliation(s)
- Simon Weinberger
- VIB Center for the Biology of Disease, VIB, Leuven, Belgium.,Center for Human Genetics, University of Leuven School of Medicine, Leuven, Belgium.,Program in Molecular and Developmental Genetics, Doctoral School for Biomedical Sciences, University of Leuven School Group Biomedicine, Leuven, Belgium
| | - Matthew P Topping
- Ear Institute, University College London, London, United Kingdom.,Centre for Mathematics and Physics in the Life Sciences and Experimental Biology (CoMPLEX), University College London, London, United Kingdom
| | - Jiekun Yan
- VIB Center for the Biology of Disease, VIB, Leuven, Belgium.,Center for Human Genetics, University of Leuven School of Medicine, Leuven, Belgium
| | - Annelies Claeys
- VIB Center for the Biology of Disease, VIB, Leuven, Belgium.,Center for Human Genetics, University of Leuven School of Medicine, Leuven, Belgium
| | - Natalie De Geest
- VIB Center for the Biology of Disease, VIB, Leuven, Belgium.,Center for Human Genetics, University of Leuven School of Medicine, Leuven, Belgium
| | - Duru Ozbay
- VIB Center for the Biology of Disease, VIB, Leuven, Belgium.,Center for Human Genetics, University of Leuven School of Medicine, Leuven, Belgium
| | - Talah Hassan
- Ear Institute, University College London, London, United Kingdom
| | - Xiaoli He
- Ear Institute, University College London, London, United Kingdom
| | - Joerg T Albert
- Ear Institute, University College London, London, United Kingdom.,Centre for Mathematics and Physics in the Life Sciences and Experimental Biology (CoMPLEX), University College London, London, United Kingdom.,Department of Cell and Developmental Biology, University College London, London, United Kingdom
| | - Bassem A Hassan
- VIB Center for the Biology of Disease, VIB, Leuven, Belgium.,Center for Human Genetics, University of Leuven School of Medicine, Leuven, Belgium.,Program in Molecular and Developmental Genetics, Doctoral School for Biomedical Sciences, University of Leuven School Group Biomedicine, Leuven, Belgium.,Institut du Cerveau et de la Moelle Epinière (ICM) - Hôpital Pitié-Salpêtrière, UPMC, Sorbonne Universités, Inserm, CNRS, Paris, France
| | - Ariane Ramaekers
- VIB Center for the Biology of Disease, VIB, Leuven, Belgium.,Center for Human Genetics, University of Leuven School of Medicine, Leuven, Belgium.,Institut du Cerveau et de la Moelle Epinière (ICM) - Hôpital Pitié-Salpêtrière, UPMC, Sorbonne Universités, Inserm, CNRS, Paris, France
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21
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Hsieh YW, Alqadah A, Chuang CF. Mechanisms controlling diversification of olfactory sensory neuron classes. Cell Mol Life Sci 2017; 74:3263-3274. [PMID: 28357469 DOI: 10.1007/s00018-017-2512-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2016] [Revised: 02/28/2017] [Accepted: 03/21/2017] [Indexed: 12/25/2022]
Abstract
Animals survive in harsh and fluctuating environments using sensory neurons to detect and respond to changes in their surroundings. Olfactory sensory neurons are essential for detecting food, identifying danger, and sensing pheromones. The ability to sense a large repertoire of different types of odors is crucial to distinguish between different situations, and is achieved through neuronal diversity within the olfactory system. Here, we review the developmental mechanisms used to establish diversity of olfactory sensory neurons in various model organisms, including Caenorhabditis elegans, Drosophila, and vertebrate models. Understanding and comparing how different olfactory neurons develop within the nervous system of different animals can provide insight into how the olfactory system is shaped in humans.
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Affiliation(s)
- Yi-Wen Hsieh
- Department of Biological Sciences, University of Illinois at Chicago, 900 S. Ashland Avenue, MC 567, Chicago, IL, 60607, USA
| | - Amel Alqadah
- Department of Biological Sciences, University of Illinois at Chicago, 900 S. Ashland Avenue, MC 567, Chicago, IL, 60607, USA
| | - Chiou-Fen Chuang
- Department of Biological Sciences, University of Illinois at Chicago, 900 S. Ashland Avenue, MC 567, Chicago, IL, 60607, USA.
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22
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Golovin RM, Broadie K. Developmental experience-dependent plasticity in the first synapse of the Drosophila olfactory circuit. J Neurophysiol 2016; 116:2730-2738. [PMID: 27683892 DOI: 10.1152/jn.00616.2016] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Accepted: 09/26/2016] [Indexed: 12/15/2022] Open
Abstract
Evidence accumulating over the past 15 years soundly refutes the dogma that the Drosophila nervous system is hardwired. The preponderance of studies reveals activity-dependent neural circuit refinement driving optimization of behavioral outputs. We describe developmental, sensory input-dependent plasticity in the brain olfactory antennal lobe, which we term long-term central adaption (LTCA). LTCA is evoked by prolonged exposure to an odorant during the first week of posteclosion life, resulting in a persistently decreased response to aversive odors and an enhanced response to attractive odors. This limited window of early-use, experience-dependent plasticity represents a critical period of olfactory circuit refinement tuned by initial sensory input. Consequent behavioral adaptations have been associated with changes in the output of olfactory projection neurons to higher brain centers. Recent studies have indicated a central role for local interneuron signaling in LTCA presentation. Genetic and molecular analyses have implicated the mRNA-binding fragile X mental retardation protein and ataxin-2 regulators, Notch trans-synaptic signaling, and cAMP signal transduction as core regulatory steps driving LTCA. In this article, we discuss the structural, functional, and behavioral changes associated with LTCA and review our current understanding of the molecular pathways underlying these developmental, experience-dependent changes in the olfactory circuitry.
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Affiliation(s)
- Randall M Golovin
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, Tennessee; and
| | - Kendal Broadie
- Vanderbilt Brain Institute, Vanderbilt University, Nashville, Tennessee; and .,Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee
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23
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Kidd S, Lieber T. Mechanism of Notch Pathway Activation and Its Role in the Regulation of Olfactory Plasticity in Drosophila melanogaster. PLoS One 2016; 11:e0151279. [PMID: 26986723 PMCID: PMC4795742 DOI: 10.1371/journal.pone.0151279] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2015] [Accepted: 02/25/2016] [Indexed: 12/20/2022] Open
Abstract
The neural plasticity of sensory systems is being increasingly recognized as playing a role in learning and memory. We have previously shown that Notch, part of an evolutionarily conserved intercellular signaling pathway, is required in adult Drosophila melanogaster olfactory receptor neurons (ORNs) for the structural and functional plasticity of olfactory glomeruli that is induced by chronic odor exposure. In this paper we address how long-term exposure to odor activates Notch and how Notch in conjunction with chronic odor mediates olfactory plasticity. We show that upon chronic odor exposure a non-canonical Notch pathway mediates an increase in the volume of glomeruli by a mechanism that is autonomous to ORNs. In addition to activating a pathway that is autonomous to ORNs, chronic odor exposure also activates the Notch ligand Delta in second order projection neurons (PNs), but this does not appear to require acetylcholine receptor activation in PNs. Delta on PNs then feeds back to activate canonical Notch signaling in ORNs, which restricts the extent of the odor induced increase in glomerular volume. Surprisingly, even though the pathway that mediates the increase in glomerular volume is autonomous to ORNs, nonproductive transsynaptic Delta/Notch interactions that do not activate the canonical pathway can block the increase in volume. In conjunction with chronic odor, the canonical Notch pathway also enhances cholinergic activation of PNs. We present evidence suggesting that this is due to increased acetylcholine release from ORNs. In regulating physiological plasticity, Notch functions solely by the canonical pathway, suggesting that there is no direct connection between morphological and physiological plasticity.
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Affiliation(s)
- Simon Kidd
- Department of Genetics and Development, Columbia University College of Physicians and Surgeons, 701 West 168th Street, New York, New York, United States of America
| | - Toby Lieber
- Department of Genetics and Development, Columbia University College of Physicians and Surgeons, 701 West 168th Street, New York, New York, United States of America
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24
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Imai Y, Kobayashi Y, Inoshita T, Meng H, Arano T, Uemura K, Asano T, Yoshimi K, Zhang CL, Matsumoto G, Ohtsuka T, Kageyama R, Kiyonari H, Shioi G, Nukina N, Hattori N, Takahashi R. The Parkinson's Disease-Associated Protein Kinase LRRK2 Modulates Notch Signaling through the Endosomal Pathway. PLoS Genet 2015; 11:e1005503. [PMID: 26355680 PMCID: PMC4565672 DOI: 10.1371/journal.pgen.1005503] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Accepted: 08/14/2015] [Indexed: 12/03/2022] Open
Abstract
Leucine-rich repeat kinase 2 (LRRK2) is a key molecule in the pathogenesis of familial and idiopathic Parkinson’s disease (PD). We have identified two novel LRRK2-associated proteins, a HECT-type ubiquitin ligase, HERC2, and an adaptor-like protein with six repeated Neuralized domains, NEURL4. LRRK2 binds to NEURL4 and HERC2 via the LRRK2 Ras of complex proteins (ROC) domain and NEURL4, respectively. HERC2 and NEURL4 link LRRK2 to the cellular vesicle transport pathway and Notch signaling, through which the LRRK2 complex promotes the recycling of the Notch ligand Delta-like 1 (Dll1)/Delta (Dl) through the modulation of endosomal trafficking. This process negatively regulates Notch signaling through cis-inhibition by stabilizing Dll1/Dl, which accelerates neural stem cell differentiation and modulates the function and survival of differentiated dopaminergic neurons. These effects are strengthened by the R1441G ROC domain-mutant of LRRK2. These findings suggest that the alteration of Notch signaling in mature neurons is a component of PD etiology linked to LRRK2. LRRK2 is linked to autosomal dominant late-onset Parkinson’s disease, suggesting that LRRK2 gain-of-function mutations lead to age-dependent degeneration of the midbrain dopaminergic neurons. In this study, we describe two novel LRRK2-associated proteins HERC2 and NEURL4, which are a ubiquitin ligase and an adaptor-like protein, respectively. HERC2 and NEURL4 direct LRRK2 to Notch signaling pathway, in which the LRRK2-NEURL4-HERC2 complex promotes the recycling of the Notch ligand Delta-like 1 (Dll1)/Delta (Dl) through the modulation of endosomal trafficking. As a result, the amounts of Dll1/D1 on the plasma membrane are increased, which affects negatively Notch signaling through cis-inhibition. The effect is enhanced by a Parkinson’s-disease associated mutation of LRRK2. Inhibition of Notch signaling in adult dopaminergic neurons impairs its functions and survival. These findings indicate a possible link between Notch pathway and Parkinson’s disease.
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Affiliation(s)
- Yuzuru Imai
- Department of Research for Parkinson's Disease, Juntendo University Graduate School of Medicine, Tokyo, Japan
- * E-mail: (YI); (NH); (RT)
| | - Yoshito Kobayashi
- Department of Neurology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
- CREST (Core Research for Evolutionary Science and Technology), Japan Science and Technology Agency, Saitama, Japan
| | - Tsuyoshi Inoshita
- Department of Research for Parkinson's Disease, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Hongrui Meng
- Research Institute for Diseases of Old Age, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Taku Arano
- Department of Research for Parkinson's Disease, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Kengo Uemura
- Department of Neurology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Takeshi Asano
- Department of Neurology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Kenji Yoshimi
- Department of Neurophysiology, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Chang-Liang Zhang
- Department of Neurology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
- CREST (Core Research for Evolutionary Science and Technology), Japan Science and Technology Agency, Saitama, Japan
| | - Gen Matsumoto
- Department of Neuroscience for Neurodegenerative Disorders, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Toshiyuki Ohtsuka
- Department of Cell Biology, Institute for Virus Research, Kyoto University, Kyoto, Japan
| | - Ryoichiro Kageyama
- Department of Cell Biology, Institute for Virus Research, Kyoto University, Kyoto, Japan
| | - Hiroshi Kiyonari
- Laboratory for Animal Resources and Genetic Engineering, RIKEN Center for Developmental Biology, Kobe, Japan
| | - Go Shioi
- Laboratory for Animal Resources and Genetic Engineering, RIKEN Center for Developmental Biology, Kobe, Japan
| | - Nobuyuki Nukina
- Department of Neuroscience for Neurodegenerative Disorders, Juntendo University Graduate School of Medicine, Tokyo, Japan
| | - Nobutaka Hattori
- Department of Research for Parkinson's Disease, Juntendo University Graduate School of Medicine, Tokyo, Japan
- CREST (Core Research for Evolutionary Science and Technology), Japan Science and Technology Agency, Saitama, Japan
- Research Institute for Diseases of Old Age, Juntendo University Graduate School of Medicine, Tokyo, Japan
- Department of Neuroscience for Neurodegenerative Disorders, Juntendo University Graduate School of Medicine, Tokyo, Japan
- Department of Neurology, Juntendo University Graduate School of Medicine, Tokyo, Japan
- * E-mail: (YI); (NH); (RT)
| | - Ryosuke Takahashi
- Department of Neurology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
- CREST (Core Research for Evolutionary Science and Technology), Japan Science and Technology Agency, Saitama, Japan
- * E-mail: (YI); (NH); (RT)
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25
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Kidd S, Struhl G, Lieber T. Notch is required in adult Drosophila sensory neurons for morphological and functional plasticity of the olfactory circuit. PLoS Genet 2015; 11:e1005244. [PMID: 26011623 PMCID: PMC4444342 DOI: 10.1371/journal.pgen.1005244] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 04/26/2015] [Indexed: 12/20/2022] Open
Abstract
Olfactory receptor neurons (ORNs) convey odor information to the central brain, but like other sensory neurons were thought to play a passive role in memory formation and storage. Here we show that Notch, part of an evolutionarily conserved intercellular signaling pathway, is required in adult Drosophila ORNs for the structural and functional plasticity of olfactory glomeruli that is induced by chronic odor exposure. Specifically, we show that Notch activity in ORNs is necessary for the odor specific increase in the volume of glomeruli that occurs as a consequence of prolonged odor exposure. Calcium imaging experiments indicate that Notch in ORNs is also required for the chronic odor induced changes in the physiology of ORNs and the ensuing changes in the physiological response of their second order projection neurons (PNs). We further show that Notch in ORNs acts by both canonical cleavage-dependent and non-canonical cleavage-independent pathways. The Notch ligand Delta (Dl) in PNs switches the balance between the pathways. These data define a circuit whereby, in conjunction with odor, N activity in the periphery regulates the activity of neurons in the central brain and Dl in the central brain regulates N activity in the periphery. Our work highlights the importance of experience dependent plasticity at the first olfactory synapse. Appropriate behavioral responses to changing environmental signals, such as odors, are essential for an organism’s survival. In Drosophila odors are detected by olfactory receptor neurons (ORNs) that synapse with second order projection neurons (PNs) and local interneurons in morphologically identifiable neuropils in the antennal lobe called glomeruli. Chronic odor exposure leads to changes in animal behavior as well as to changes in the activity of neurons in the olfactory circuit and increases in the volume of glomeruli. Here, we establish that Notch, an evolutionarily conserved transmembrane receptor that plays profound and pervasive roles in animal development, is required in adult Drosophila ORNs for functional and morphological plasticity in response to chronic odor exposure. These findings are significant because they point to a role for Notch in regulating activity dependent plasticity. Furthermore, we show that in regulating the odor dependent change in glomerular volume, Notch acts by both non-canonical, cleavage-independent and canonical, cleavage-dependent mechanisms, with the Notch ligand Delta in PNs switching the balance between the pathways. Because both the Notch pathway and the processing of olfactory information are highly conserved between flies and vertebrates these findings are likely to be of general relevance.
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Affiliation(s)
- Simon Kidd
- Department of Genetics and Development, Columbia University College of Physicians and Surgeons, New York, New York, United States of America
| | - Gary Struhl
- Department of Genetics and Development, Columbia University College of Physicians and Surgeons, New York, New York, United States of America
| | - Toby Lieber
- Department of Genetics and Development, Columbia University College of Physicians and Surgeons, New York, New York, United States of America
- * E-mail:
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Current techniques for high-resolution mapping of behavioral circuits in Drosophila. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2015; 201:895-909. [DOI: 10.1007/s00359-015-1010-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Revised: 04/09/2015] [Accepted: 04/11/2015] [Indexed: 10/23/2022]
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Abstract
Memory is a temporally evolving molecular and structural process, which involves changes from local synapses to complex neural networks. There is increasing evidence for an involvement of developmental pathways in regulating synaptic communication in the adult nervous system. Notch signaling has been implicated in memory formation in a variety of species. Nevertheless, the mechanism of Notch underlying memory consolidation remains poorly understood. In this commentary, besides offering an overview of the advances in the field of Notch in memory, we highlight some of the weaknesses of the studies and attempt to cast light on the apparent discrepancies on the role of Notch in memory. We believe that future studies, employing high-throughput technologies and targeted Notch loss and gain of function animal models, will reveal the mechanisms of Notch dependent plasticity and resolve whether this signaling pathway is implicated in the cognitive deficit associated with dementia.
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Affiliation(s)
- Swananda Marathe
- Department of Medicine, Institute of Anatomy, University of Fribourg, Fribourg, Switzerland
| | - Lavinia Alberi
- Department of Medicine, Institute of Anatomy, University of Fribourg, Fribourg, Switzerland
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Liu S, Wang Y, Worley PF, Mattson MP, Gaiano N. The canonical Notch pathway effector RBP-J regulates neuronal plasticity and expression of GABA transporters in hippocampal networks. Hippocampus 2015; 25:670-8. [PMID: 25515406 DOI: 10.1002/hipo.22402] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/07/2014] [Indexed: 01/28/2023]
Abstract
Activation of the Notch pathway in neurons is essential for learning and memory in various species from invertebrates to mammals. However, it remains unclear how Notch signaling regulates neuronal plasticity, and whether the transcriptional regulator and canonical pathway effector RBP-J plays a role. Here, we report that conditional disruption of RBP-J in the postnatal hippocampus leads to defects in long-term potentiation, long-term depression, and in learning and memory. Using gene expression profiling and chromatin immunoprecipitation, we identified two GABA transporters, GAT2 and BGT1, as putative Notch/RBP-J pathway targets, which may function downstream of RBP-J to limit the accumulation of GABA in the Schaffer collateral pathway. Our results reveal an essential role for canonical Notch/RBP-J signaling in hippocampal synaptic plasticity and suggest that role, at least in part, is mediated by the regulation of GABAergic signaling.
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Affiliation(s)
- Shuxi Liu
- Neuroregeneration Program, Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland
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Abstract
Memory is a temporally evolving molecular and structural process, which involves changes from local synapses to complex neural networks. There is increasing evidence for an involvement of developmental pathways in regulating synaptic communication in the adult nervous system. Notch signaling has been implicated in memory formation in a variety of species. Nevertheless, the mechanism of Notch in memory consolidation remains poorly understood. In this commentary, besides offering an overview of the advances in the field of Notch in memory, we highlight some of the weaknesses of the studies and attempt to cast light on some of the apparent discrepancies on the role of Notch in memory. We believe that future studies, employing high-throughput technologies and targeted Notch loss and gain of function animal models, will reveal the mechanisms of Notch-dependent plasticity and resolve whether this signaling pathway is implicated in the cognitive deficit associated with dementia.
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Affiliation(s)
- Swananda Marathe
- Institute of Anatomy, Department of Medicine, University of Fribourg, Fribourg, Switzerland
| | - Lavinia Alberi
- Institute of Anatomy, Department of Medicine, University of Fribourg, Fribourg, Switzerland
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Brai E, Marathe S, Zentilin L, Giacca M, Nimpf J, Kretz R, Scotti A, Alberi L. Notch1 activity in the olfactory bulb is odour-dependent and contributes to olfactory behaviour. Eur J Neurosci 2014; 40:3436-49. [PMID: 25234246 DOI: 10.1111/ejn.12719] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Revised: 08/11/2014] [Accepted: 08/12/2014] [Indexed: 11/28/2022]
Abstract
Notch signalling plays an important role in synaptic plasticity, learning and memory functions in both Drosophila and rodents. In this paper, we report that this feature is not restricted to hippocampal networks but also involves the olfactory bulb (OB). Odour discrimination and olfactory learning in rodents are essential for survival. Notch1 expression is enriched in mitral cells of the mouse OB. These principal neurons are responsive to specific input odorants and relay the signal to the olfactory cortex. Olfactory stimulation activates a subset of mitral cells, which show an increase in Notch activity. In Notch1cKOKln mice, the loss of Notch1 in mitral cells affects the magnitude of the neuronal response to olfactory stimuli. In addition, Notch1cKOKln mice display reduced olfactory aversion to propionic acid as compared to wildtype controls. This indicates, for the first time, that Notch1 is involved in olfactory processing and may contribute to olfactory behaviour.
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Affiliation(s)
- Emanuele Brai
- Unit of Anatomy, Department of Medicine, University of Fribourg, Route de Gockel, 1, Fribourg, Switzerland
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Kuhlmann K, Tschapek A, Wiese H, Eisenacher M, Meyer HE, Hatt HH, Oeljeklaus S, Warscheid B. The membrane proteome of sensory cilia to the depth of olfactory receptors. Mol Cell Proteomics 2014; 13:1828-43. [PMID: 24748648 DOI: 10.1074/mcp.m113.035378] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In the nasal cavity, the nonmotile cilium of olfactory sensory neurons (OSNs) constitutes the chemosensory interface between the ambient environment and the brain. The unique sensory organelle facilitates odor detection for which it includes all necessary components of initial and downstream olfactory signal transduction. In addition to its function in olfaction, a more universal role in modulating different signaling pathways is implicated, for example, in neurogenesis, apoptosis, and neural regeneration. To further extend our knowledge about this multifunctional signaling organelle, it is of high importance to establish a most detailed proteome map of the ciliary membrane compartment down to the level of transmembrane receptors. We detached cilia from mouse olfactory epithelia via Ca(2+)/K(+) shock followed by the enrichment of ciliary membrane proteins at alkaline pH, and we identified a total of 4,403 proteins by gel-based and gel-free methods in conjunction with high resolution LC/MS. This study is the first to report the detection of 62 native olfactory receptor proteins and to provide evidence for their heterogeneous expression at the protein level. Quantitative data evaluation revealed four ciliary membrane-associated candidate proteins (the annexins ANXA1, ANXA2, ANXA5, and S100A5) with a suggested function in the regulation of olfactory signal transduction, and their presence in ciliary structures was confirmed by immunohistochemistry. Moreover, we corroborated the ciliary localization of the potassium-dependent Na(+)/Ca(2+) exchanger (NCKX) 4 and the plasma membrane Ca(2+)-ATPase 1 (PMCA1) involved in olfactory signal termination, and we detected for the first time NCKX2 in olfactory cilia. Through comparison with transcriptome data specific for mature, ciliated OSNs, we finally delineated the membrane ciliome of OSNs. The membrane proteome of olfactory cilia established here is the most complete today, thus allowing us to pave new avenues for the study of diverse molecular functions and signaling pathways in and out of olfactory cilia and thus to advance our understanding of the biology of sensory organelles in general.
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Affiliation(s)
- Katja Kuhlmann
- From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, Universitätsstrasse 150, 44780 Bochum
| | - Astrid Tschapek
- From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, Universitätsstrasse 150, 44780 Bochum
| | - Heike Wiese
- the ¶Faculty of Biology and BIOSS Centre for Biological Signalling Studies, University of Freiburg, Schänzlestrasse 1, 79104 Freiburg
| | - Martin Eisenacher
- From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, Universitätsstrasse 150, 44780 Bochum
| | - Helmut E Meyer
- From the ‡Medizinisches Proteom-Center, Ruhr-Universität Bochum, Universitätsstrasse 150, 44780 Bochum, the ‖Leibniz-Institut für Analytische Wissenschaften-ISAS-e.V., Otto-Hahn-Strasse 6b, 44227 Dortmund, and
| | - Hanns H Hatt
- the **Department of Cell Physiology, Ruhr-Universität Bochum, Universitätsstrasse 150, 44780 Bochum, Germany
| | - Silke Oeljeklaus
- the ¶Faculty of Biology and BIOSS Centre for Biological Signalling Studies, University of Freiburg, Schänzlestrasse 1, 79104 Freiburg
| | - Bettina Warscheid
- the ¶Faculty of Biology and BIOSS Centre for Biological Signalling Studies, University of Freiburg, Schänzlestrasse 1, 79104 Freiburg,
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Neville MC, Nojima T, Ashley E, Parker DJ, Walker J, Southall T, Van de Sande B, Marques AC, Fischer B, Brand AH, Russell S, Ritchie MG, Aerts S, Goodwin SF. Male-specific fruitless isoforms target neurodevelopmental genes to specify a sexually dimorphic nervous system. Curr Biol 2014; 24:229-41. [PMID: 24440396 PMCID: PMC3969260 DOI: 10.1016/j.cub.2013.11.035] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 11/18/2013] [Accepted: 11/19/2013] [Indexed: 02/06/2023]
Abstract
Background In Drosophila, male courtship behavior is regulated in large part by the gene fruitless (fru). fru encodes a set of putative transcription factors that promote male sexual behavior by controlling the development of sexually dimorphic neuronal circuitry. Little is known about how Fru proteins function at the level of transcriptional regulation or the role that isoform diversity plays in the formation of a male-specific nervous system. Results To characterize the roles of sex-specific Fru isoforms in specifying male behavior, we generated novel isoform-specific mutants and used a genomic approach to identify direct Fru isoform targets during development. We demonstrate that all Fru isoforms directly target genes involved in the development of the nervous system, with individual isoforms exhibiting unique binding specificities. We observe that fru behavioral phenotypes are specified by either a single isoform or a combination of isoforms. Finally, we illustrate the utility of these data for the identification of novel sexually dimorphic genomic enhancers and novel downstream regulators of male sexual behavior. Conclusions These findings suggest that Fru isoform diversity facilitates both redundancy and specificity in gene expression, and that the regulation of neuronal developmental genes may be the most ancient and conserved role of fru in the specification of a male-specific nervous system. Isoform-specific fru mutants reveal both functional redundancy and specificity Fru isoform-specific genomic occupancy is characterized in the Drosophila nervous system All Fru isoforms directly target neuronal morphogenesis genes Isoform-specific motifs are associated with specific Fru isoform occupancy
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Affiliation(s)
- Megan C Neville
- Department of Physiology, Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK.
| | - Tetsuya Nojima
- Department of Physiology, Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Elizabeth Ashley
- Department of Physiology, Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Darren J Parker
- Centre for Biological Diversity, University of St Andrews, St Andrews, KY16 9TH, UK
| | - John Walker
- Department of Physiology, Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Tony Southall
- The Gurdon Institute and Department of Physiology, Development and Neuroscience, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK
| | - Bram Van de Sande
- Laboratory of Computational Biology, Department of Human Genetics, University of Leuven, 3000 Leuven, Belgium
| | - Ana C Marques
- Department of Physiology, Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK
| | - Bettina Fischer
- Cambridge Systems Biology Centre, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK; Department of Genetics, University of Cambridge, Downing Street, Cambridge CB2 3EH, UK
| | - Andrea H Brand
- The Gurdon Institute and Department of Physiology, Development and Neuroscience, University of Cambridge, Tennis Court Road, Cambridge CB2 1QN, UK
| | - Steven Russell
- Cambridge Systems Biology Centre, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK; Department of Genetics, University of Cambridge, Downing Street, Cambridge CB2 3EH, UK
| | - Michael G Ritchie
- Centre for Biological Diversity, University of St Andrews, St Andrews, KY16 9TH, UK
| | - Stein Aerts
- Laboratory of Computational Biology, Department of Human Genetics, University of Leuven, 3000 Leuven, Belgium
| | - Stephen F Goodwin
- Department of Physiology, Anatomy and Genetics, University of Oxford, Sherrington Building, Parks Road, Oxford OX1 3PT, UK.
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Abstract
Notch signaling is probably the most widely used intercellular communication pathway. The Notch mutant in the fruit fly Drosophila melanogaster was isolated about 100 years ago at the dawn of genetics. Since then, research on Notch and its related genes in flies, worms, mice, and human has led to the establishment of an evolutionarily conserved signaling pathway, the Notch signaling pathway. In the past few decades, molecular cloning of the Notch signaling components as well as genetic, cell biological, biochemical, structural, and bioinformatic approaches have uncovered the basic molecular logic of the pathway. In addition, genetic screens and systems approaches have led to the expansion of the list of genes that interact and fine-tune the pathway in a context specific manner. Furthermore, recent human genetic and genomic studies have led to the discovery that Notch plays a role in numerous diseases such as congenital disorders, stroke, and especially cancer. Pharmacological studies are actively pursuing key components of the pathway as drug targets for potential therapy. In this chapter, we will provide a brief historical overview of Notch signaling research and discuss the basic principles of Notch signaling, focusing on the unique features of this pathway when compared to other signaling pathways. Further studies to understand and manipulate Notch signaling in vivo in model organisms and in clinical settings will require a combination of a number of different approaches that are discussed throughout this book.
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Multi-unit recording with iridium oxide modified stereotrodes in Drosophila melanogaster. J Neurosci Methods 2013; 222:218-29. [PMID: 24286699 DOI: 10.1016/j.jneumeth.2013.11.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Revised: 11/15/2013] [Accepted: 11/17/2013] [Indexed: 11/21/2022]
Abstract
BACKGROUND Drosophila is a very favorable animal model for the studies of neuroscience. However, it remains a great challenge to employ electrophysiological approaches in Drosophila to study the neuronal assembly dynamics in vivo, partially due to the small size of the Drosophila brain. Small and sensitive microelectrodes for multi-unit recordings are greatly desired. NEW METHOD We fabricated micro-scale stereotrodes for electrical recordings in Drosophila melanogaster. The stereotrodes were modified with iridium oxide (IrO2) under a highly controllable deposition procedure to improve their electrochemical properties. Electrical recordings were carried out using the IrO2 stereotrodes to detect spontaneous action potentials and LFPs in vivo. RESULTS The IrO2 electrodes exhibited significantly higher capacitance and lower impedance at 1 kHz. Electrical recording with the IrO2 stereotrodes in vivo demonstrated an average signal-to-noise ratio (SNR) of 7.3 and a significantly improved LFP sensitivity. 5 types of different neurons recorded were clearly separated. Electrophysiological responses to visual and odor stimulation were also detected, respectively. COMPARISON WITH EXISTING METHOD(S) The most widely used electrodes for electrical recording in Drosophila are glass microelectrode and sharpened tungsten microelectrode, which are typically used for single-unit recordings. Although tetrode technology has been used to record multi-neuronal activities from Drosophila, the fabricated IrO2 stereotrodes possess smaller geometry size but exhibited comparable recording signal-to noise ration and better sorting quality. CONCLUSIONS The IrO2 stereotrodes are capable to meet the requirements of multi-unit recording and spike sorting, which will be a useful tool for the electrophysiology-based researches especially in Drosophila and other small animals.
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Zhang J, Yin JCP, Wesley CS. From Drosophila development to adult: clues to Notch function in long-term memory. Front Cell Neurosci 2013; 7:222. [PMID: 24312012 PMCID: PMC3836050 DOI: 10.3389/fncel.2013.00222] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Accepted: 11/03/2013] [Indexed: 12/26/2022] Open
Abstract
Notch is a cell surface receptor that is well known to mediate inter-cellular communication during animal development. Data in the field indicate that it is also involved in the formation of long-term memory (LTM) in the fully developed adults and in memory loss upon neurodegeneration. Our studies in the model organism Drosophila reveal that a non-canonical Notch-protein kinase C activity that plays critical roles in embryonic development also regulates cyclic-AMP response element binding protein during LTM formation in adults. Here we present a perspective on how the various known features of Notch function relate to LTM formation and how they might interface with elements of Wingless/Wnt signaling in this process.
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Affiliation(s)
- Jiabin Zhang
- Neuroscience Training Program, University of Wisconsin-Madison Madison, WI, USA ; Department of Genetics and Medical Genetics, University of Wisconsin-Madison Madison, WI, USA
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Notch signaling activation promotes seizure activity in temporal lobe epilepsy. Mol Neurobiol 2013; 49:633-44. [PMID: 23999872 DOI: 10.1007/s12035-013-8545-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 08/19/2013] [Indexed: 10/26/2022]
Abstract
Notch signaling in the nervous system is often regarded as a developmental pathway. However, recent studies have suggested that Notch is associated with neuronal discharges. Here, focusing on temporal lobe epilepsy, we found that Notch signaling was activated in the kainic acid (KA)-induced epilepsy model and in human epileptogenic tissues. Using an acute model of seizures, we showed that DAPT, an inhibitor of Notch, inhibited ictal activity. In contrast, pretreatment with exogenous Jagged1 to elevate Notch signaling before KA application had proconvulsant effects. In vivo, we demonstrated that the impacts of activated Notch signaling on seizures can in part be attributed to the regulatory role of Notch signaling on excitatory synaptic activity in CA1 pyramidal neurons. In vitro, we found that DAPT treatment impaired synaptic vesicle endocytosis in cultured hippocampal neurons. Taken together, our findings suggest a correlation between aberrant Notch signaling and epileptic seizures. Notch signaling is up-regulated in response to seizure activity, and its activation further promotes neuronal excitation of CA1 pyramidal neurons in acute seizures.
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Giagtzoglou N, Li T, Yamamoto S, Bellen HJ. Drosophila EHBP1 regulates Scabrous secretion during Notch-mediated lateral inhibition. J Cell Sci 2013; 126:3686-96. [PMID: 23788431 DOI: 10.1242/jcs.126292] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Notch signaling is an evolutionarily conserved pathway that plays a central role in numerous developmental and disease processes. The versatility of the Notch pathway relies on the activity of context-dependent regulators. These include rab11, sec15, arp3 and Drosophila EHBP1 (dEHBP1), which control Notch signaling and cell fate acquisition in asymmetrically dividing mechanosensory lineages by regulating the trafficking of the ligand Delta. Here, we show that dEHBP1 also controls the specification of R8 photoreceptors, as its loss results in the emergence of supernumerary R8 photoreceptors. Given the requirements for Notch signaling during lateral inhibition, we propose that dEHBP1 regulates distinct aspects of Notch signaling in different developmental contexts. We show that dEHBP1 regulates the exocytosis of Scabrous, a positive regulator of Notch signaling. In conclusion, dEHBP1 provides developmental versatility of intercellular signaling by regulating the trafficking of distinct Notch signaling components.
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Affiliation(s)
- Nikolaos Giagtzoglou
- Department of Molecular and Human Genetics, Jan and Dan Duncan Neurological Research Institute, Baylor College of Medicine, Houston, TX 77030, USA
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Brown EB, Layne JE, Zhu C, Jegga AG, Rollmann SM. Genome-wide association mapping of natural variation in odour-guided behaviour inDrosophila. GENES BRAIN AND BEHAVIOR 2013; 12:503-15. [DOI: 10.1111/gbb.12048] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2013] [Revised: 05/01/2013] [Accepted: 05/11/2013] [Indexed: 11/26/2022]
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Alberi L, Hoey SE, Brai E, Scotti AL, Marathe S. Notch signaling in the brain: in good and bad times. Ageing Res Rev 2013; 12:801-14. [PMID: 23570941 DOI: 10.1016/j.arr.2013.03.004] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 03/16/2013] [Accepted: 03/22/2013] [Indexed: 01/13/2023]
Abstract
Notch signaling is an evolutionarily conserved pathway, which is fundamental for neuronal development and specification. In the last decade, increasing evidence has pointed out an important role of this pathway beyond embryonic development, indicating that Notch also displays a critical function in the mature brain of vertebrates and invertebrates. This pathway appears to be involved in neural progenitor regulation, neuronal connectivity, synaptic plasticity and learning/memory. In addition, Notch appears to be aberrantly regulated in neurodegenerative diseases, including Alzheimer's disease and ischemic injury. The molecular mechanisms by which Notch displays these functions in the mature brain are not fully understood, but are currently the subject of intense research. In this review, we will discuss old and novel Notch targets and molecular mediators that contribute to Notch function in the mature brain and will summarize recent findings that explore the two facets of Notch signaling in brain physiology and pathology.
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Affiliation(s)
- Lavinia Alberi
- Unit of Anatomy, Department of Medicine, University of Fribourg, Switzerland.
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Sato C, Turkoz M, Dearborn JT, Wozniak DF, Kopan R, Hass MR. Loss of RBPj in postnatal excitatory neurons does not cause neurodegeneration or memory impairments in aged mice. PLoS One 2012; 7:e48180. [PMID: 23110206 PMCID: PMC3482205 DOI: 10.1371/journal.pone.0048180] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Accepted: 09/25/2012] [Indexed: 02/04/2023] Open
Abstract
Previous studies suggest that loss of γ-secretase activity in postnatal mouse brains causes age-dependent memory impairment and neurodegeneration. Due to the diverse array of γ-secretase substrates, it remains to be demonstrated whether loss of cleavage of any specific substrate(s) is responsible for these defects. The bulk of the phenotypes observed in mammals deficient for γ-secretase or exposed to γ-secretase inhibitors are caused by the loss of Notch receptor proteolysis. Accordingly, inhibition of Notch signaling is the main cause for untoward effects for γ-secretase inhibitors as therapeutics for Alzheimer's disease. Therefore, we wished to determine if loss of canonical Notch signaling is responsible for the age-dependent neurodegeneration observed upon γ-secrectase deficiency in the mouse brain. We generated postnatal forebrain-specific RBPj conditional knockout (cKO) mice using the CamKII-Cre driver and examined behavior and brain pathology in 12-18 month old animals. Since all four mammalian Notch receptor homologues signal via this DNA binding protein, these mice lack canonical Notch signaling. We found that loss of RBPj in mature excitatory neurons was well tolerated, with no evidence for neurodegeneration or of learning and memory impairment in mice aged up to 18 months. The only phenotypic deficit we observed in the RBPj-deficient mice was a subtle abnormality in olfactory preferences, particularly in females. We conclude that the loss of canonical Notch signaling through the four receptors is not responsible for age-dependent neurodegeneration or learning and memory deficits seen in γ-secretase deficient mice.
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Affiliation(s)
- Chihiro Sato
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Mustafa Turkoz
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Joshua T. Dearborn
- Department of Psychiatry, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - David F. Wozniak
- Department of Psychiatry, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Raphael Kopan
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Matthew R. Hass
- Department of Developmental Biology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- * E-mail:
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41
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Giniger E. Notch signaling and neural connectivity. Curr Opin Genet Dev 2012; 22:339-46. [PMID: 22608692 DOI: 10.1016/j.gde.2012.04.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Revised: 04/02/2012] [Accepted: 04/11/2012] [Indexed: 01/23/2023]
Abstract
The cell surface receptor Notch contributes to the development of nearly every tissue in most metazoans by controlling the fates and differentiation of cells. Recent results have now established that Notch also regulates the connectivity of the nervous system, and does so at a variety of levels, including specification of neuronal identity, division, survival and migration, as well as axon guidance, morphogenesis of dendritic arbors and weighting of synapse strength. To these ends, Notch engages at least two signal transduction pathways, one that controls nuclear gene expression and another that directly targets the cytoskeleton. Coordinating the many functions of Notch to produce neural structure is thus a pivotal aspect of building and maintaining the nervous system.
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Affiliation(s)
- Edward Giniger
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA.
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Yaron A, Sprinzak D. The cis side of juxtacrine signaling: a new role in the development of the nervous system. Trends Neurosci 2012; 35:230-9. [PMID: 22222351 DOI: 10.1016/j.tins.2011.12.003] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2011] [Revised: 09/30/2011] [Accepted: 12/05/2011] [Indexed: 12/18/2022]
Abstract
Cell-cell communication by juxtacrine signaling plays a key role in the development of the nervous system, from cell fate determination through axonal guidance to synaptogenesis. Interestingly, several juxtacrine signaling systems exhibit an inhibitory interaction between receptors and ligands in the same cell, termed cis inhibition. These include the Notch, semaphorin and ephrin signaling systems. Here we review the role of cis inhibition in these signaling systems in the development of the nervous system. We compare and contrast cis inhibition mechanisms and discuss their potential cellular function as a threshold-generating mechanism. The prevalence of cis inhibition suggests that these interactions and their functional regulatory roles may serve as a general design principle for juxtacrine signaling-mediated processes during and beyond neurodevelopment.
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Affiliation(s)
- Avraham Yaron
- Department of Biological Chemistry, Weizmann Institute of Science, Rehovot 76100, Israel.
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From Notch signaling to fine-grained patterning: Modeling meets experiments. Curr Opin Genet Dev 2011; 21:732-9. [PMID: 21862316 DOI: 10.1016/j.gde.2011.07.007] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2011] [Accepted: 07/20/2011] [Indexed: 11/20/2022]
Abstract
Notch signaling is the canonical signaling pathway between neighboring cells. It plays an important role in fine-grained patterning processes such as the formation of checkerboard-like differentiation patterns and sharp boundaries between developing tissues. While detailed information about many of the genes and proteins involved have been identified, we still lack a quantitative mechanistic understanding of these processes. Here we discuss several recent studies that provide novel insights into Notch-dependent patterning by combining mathematical models with quantitative experimental results. Such approaches allow identification of mechanisms and design principles controlling how patterns are generated in a reproducible and robust manner.
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Ables JL, Breunig JJ, Eisch AJ, Rakic P. Not(ch) just development: Notch signalling in the adult brain. Nat Rev Neurosci 2011; 12:269-83. [PMID: 21505516 DOI: 10.1038/nrn3024] [Citation(s) in RCA: 319] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The Notch pathway is often regarded as a developmental pathway, but components of Notch signalling are expressed and active in the adult brain. With the advent of more sophisticated genetic manipulations, evidence has emerged that suggests both conserved and novel roles for Notch signalling in the adult brain. Not surprisingly, Notch is a key regulator of adult neural stem cells, but it is increasingly clear that Notch signalling also has roles in the regulation of migration, morphology, synaptic plasticity and survival of immature and mature neurons. Understanding the many functions of Notch signalling in the adult brain, and its dysfunction in neurodegenerative disease and malignancy, is crucial to the development of new therapeutics that are centred around this pathway.
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Affiliation(s)
- Jessica L Ables
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA
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Social regulation of aggression by pheromonal activation of Or65a olfactory neurons in Drosophila. Nat Neurosci 2011; 14:896-902. [PMID: 21685916 DOI: 10.1038/nn.2836] [Citation(s) in RCA: 107] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2011] [Accepted: 04/14/2011] [Indexed: 12/14/2022]
Abstract
When two socially naive Drosophila males meet, they will fight. However, prior social grouping of males reduces their aggression. We found olfactory communication to be important for modulating Drosophila aggression. Although acute exposure to the male-specific pheromone 11-cis-vaccenyl acetate (cVA) elicited aggression through Or67d olfactory receptor neurons (ORNs), chronic cVA exposure reduced aggression through Or65a ORNs. Or65a ORNs were not acutely involved in aggression, but blockade of synaptic transmission of Or65a ORNs during social grouping or prior chronic cVA exposure eliminated social modulation of aggression. Artificial activation of Or65a ORNs by ectopic expression of the Drosophila gene TrpA1 was sufficient to reduce aggression. Social suppression of aggression requires subsets of local interneurons in the antennal lobe. Our results indicate that activation of Or65a ORNs is important for social modulation of male aggression, demonstrate that the acute and chronic effects of a single pheromone are mediated by two distinct types of ORNs, reveal a behaviorally important role for interneurons and suggest a chemical method to reduce aggression in animals.
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Abstract
The Notch pathway is prominent among those known to regulate neural development in vertebrates. Notch receptor activation can inhibit neurogenesis, maintain neural progenitor character, and in some contexts promote gliogenesis and drive binary fate choices. Recently, a wave of exciting studies has emerged, which has both solidified previously held assertions and expanded our understanding of Notch function during neurogenesis and in the adult brain. These studies have examined pathway regulators and interactions, as well as pathway dynamics, with respect to both gene expression and cell-cell signaling. Here, focusing primarily on vertebrates, we review the current literature on Notch signaling in the nervous system, and highlight numerous recent studies that have generated interesting and unexpected advances.
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