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Miyashita T, Murakami K, Kikuchi E, Ofusa K, Mikami K, Endo K, Miyaji T, Moriyama S, Konno K, Muratani H, Moriyama Y, Watanabe M, Horiuchi J, Saitoe M. Glia transmit negative valence information during aversive learning in Drosophila. Science 2023; 382:eadf7429. [PMID: 38127757 DOI: 10.1126/science.adf7429] [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: 11/10/2022] [Accepted: 10/20/2023] [Indexed: 12/23/2023]
Abstract
During Drosophila aversive olfactory conditioning, aversive shock information needs to be transmitted to the mushroom bodies (MBs) to associate with odor information. We report that aversive information is transmitted by ensheathing glia (EG) that surround the MBs. Shock induces vesicular exocytosis of glutamate from EG. Blocking exocytosis impairs aversive learning, whereas activation of EG can replace aversive stimuli during conditioning. Glutamate released from EG binds to N-methyl-d-aspartate receptors in the MBs, but because of Mg2+ block, Ca2+ influx occurs only when flies are simultaneously exposed to an odor. Vesicular exocytosis from EG also induces shock-associated dopamine release, which plays a role in preventing formation of inappropriate associations. These results demonstrate that vesicular glutamate released from EG transmits negative valence information required for associative learning.
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Affiliation(s)
- Tomoyuki Miyashita
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Kanako Murakami
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
- Department of Biological Science, Graduate School of Science, Tokyo Metropolitan University, Tokyo 192-0397, Japan
| | - Emi Kikuchi
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Kyouko Ofusa
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Kyohei Mikami
- Center for Basic Technology Research, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Kentaro Endo
- Center for Basic Technology Research, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Takaaki Miyaji
- Department of Molecular Membrane Biology, Faculty of Pharmaceutical Sciences, Okayama University, Okayama 700-8530, Japan
- Department of Genomics and Proteomics, Advanced Science Research Center, Okayama University, Okayama 700-8530, Japan
| | - Sawako Moriyama
- Division of Endocrinology and Metabolism, Department of Internal Medicine, School of Medicine, Kurume University, Fukuoka 830-0011, Japan
| | - Kotaro Konno
- Department of Anatomy, Faculty of Medicine, Hokkaido University, Hokkaido 060-8368, Japan
| | - Hinako Muratani
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
- Department of Engineering Science, Graduate School of Informatics and Engineering, The University of Electro-Communications, Tokyo 182-8585, Japan
| | - Yoshinori Moriyama
- Division of Endocrinology and Metabolism, Department of Internal Medicine, School of Medicine, Kurume University, Fukuoka 830-0011, Japan
| | - Masahiko Watanabe
- Department of Anatomy, Faculty of Medicine, Hokkaido University, Hokkaido 060-8368, Japan
| | - Junjiro Horiuchi
- Center for Basic Technology Research, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
| | - Minoru Saitoe
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
- Center for Basic Technology Research, Tokyo Metropolitan Institute of Medical Science, Tokyo 156-8506, Japan
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2
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Davis RL. Learning and memory using Drosophila melanogaster: a focus on advances made in the fifth decade of research. Genetics 2023; 224:iyad085. [PMID: 37212449 PMCID: PMC10411608 DOI: 10.1093/genetics/iyad085] [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: 02/16/2023] [Accepted: 05/03/2023] [Indexed: 05/23/2023] Open
Abstract
In the last decade, researchers using Drosophila melanogaster have made extraordinary progress in uncovering the mysteries underlying learning and memory. This progress has been propelled by the amazing toolkit available that affords combined behavioral, molecular, electrophysiological, and systems neuroscience approaches. The arduous reconstruction of electron microscopic images resulted in a first-generation connectome of the adult and larval brain, revealing complex structural interconnections between memory-related neurons. This serves as substrate for future investigations on these connections and for building complete circuits from sensory cue detection to changes in motor behavior. Mushroom body output neurons (MBOn) were discovered, which individually forward information from discrete and non-overlapping compartments of the axons of mushroom body neurons (MBn). These neurons mirror the previously discovered tiling of mushroom body axons by inputs from dopamine neurons and have led to a model that ascribes the valence of the learning event, either appetitive or aversive, to the activity of different populations of dopamine neurons and the balance of MBOn activity in promoting avoidance or approach behavior. Studies of the calyx, which houses the MBn dendrites, have revealed a beautiful microglomeruluar organization and structural changes of synapses that occur with long-term memory (LTM) formation. Larval learning has advanced, positioning it to possibly lead in producing new conceptual insights due to its markedly simpler structure over the adult brain. Advances were made in how cAMP response element-binding protein interacts with protein kinases and other transcription factors to promote the formation of LTM. New insights were made on Orb2, a prion-like protein that forms oligomers to enhance synaptic protein synthesis required for LTM formation. Finally, Drosophila research has pioneered our understanding of the mechanisms that mediate permanent and transient active forgetting, an important function of the brain along with acquisition, consolidation, and retrieval. This was catalyzed partly by the identification of memory suppressor genes-genes whose normal function is to limit memory formation.
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Affiliation(s)
- Ronald L Davis
- Department of Neuroscience, Herbert Wertheim UF Scripps Institute for Biomedical Innovation & Technology, University of Florida, 130 Scripps Way, Jupiter, FL 33458, USA
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3
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Ojo VOA, Adelusi OO, Idowu OJ, Shittu OO, Okeniyi FA, Ogundapo BM, Dada FI, Oso AO. Effect of increasing levels of Leucaena leucocephala seeds to grass pellets on performance of grower rabbits. Trop Anim Health Prod 2023; 55:221. [PMID: 37221313 DOI: 10.1007/s11250-023-03630-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 05/09/2023] [Indexed: 05/25/2023]
Abstract
The study was carried out to determine the chemical composition of composite pellets of Megathyrsus maximus containing Leucaena leucocephala seed meal at the varying level and growth responses, as well as haematological and serum biochemical of rabbits, fed the pellets for 60 days. The treatment consists of M. maximus and L. leucocephala-100:0, 90:10, 80:20, 70:30 and 60:40, respectively. Results revealed an increase (P < 0.05) in the proximate composition of the grass pellets with an increase in seed inclusion while there was a reduction (P < 0.05) in the NDF contents of the pellets. An increase in the tannin contents was recorded with an increase in seed inclusion to the grass pellets. Rabbits fed with 30 and 40% inclusions of seed in the grass pellets had similar weight gain while the lowest feed conversion ratio was recorded in rabbits fed grass with 30% seed inclusion. Packed cell volume, RBC and lymphocyte in rabbits were altered with feeding grass seed pellet (P < 0.05), although no particular pattern was followed. Total protein, globulin and urea contents were reduced in the rabbits as the contents of the seeds in the grass pellets increased. Albumin contents in pellets with 30% of seeds were higher in the rabbits fed the pellets above other treatments. It can be concluded that increasing the seed meal level up to 30% in grass pellets supported growth response without inflicting any side effects on the health indices of the rabbits.
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Affiliation(s)
- V O A Ojo
- Department of Pasture and Range Management, Federal University of Agriculture, P. M. B, Abeokuta, 2240, Nigeria.
| | - O O Adelusi
- Department of Animal Nutrition, Federal University of Agriculture, P. M. B, Abeokuta, 2240, Nigeria
| | - O J Idowu
- Department of Pasture and Range Management, Federal University of Agriculture, P. M. B, Abeokuta, 2240, Nigeria
| | - O O Shittu
- Institute of Food Security, Environmental Resources and Agricultural Research, Federal University of Agriculture, Abeokuta, Ogun State, Nigeria
| | - F A Okeniyi
- Department of Animal Science, College of Agriculture, Landmark University, PMB 1001, Omu-Aran, Kwara State, Nigeria
| | - B M Ogundapo
- Department of Pasture and Range Management, Federal University of Agriculture, P. M. B, Abeokuta, 2240, Nigeria
| | - F I Dada
- Livestock Science and Sustainable Environment, Centre for Excellence in Agricultural Development and Sustainable Environment, Federal University of Agriculture, Abeokuta, Ogun State, Nigeria
| | - A O Oso
- Department of Animal Nutrition, Federal University of Agriculture, P. M. B, Abeokuta, 2240, Nigeria
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Hobin M, Dorfman K, Adel M, Rivera-Rodriguez EJ, Kuklin EA, Ma D, Griffith LC. The Drosophila microRNA bantam regulates excitability in adult mushroom body output neurons to promote early night sleep. iScience 2022; 25:104874. [PMID: 36034229 PMCID: PMC9400086 DOI: 10.1016/j.isci.2022.104874] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 07/07/2022] [Accepted: 07/29/2022] [Indexed: 11/23/2022] Open
Abstract
Sleep circuitry evolved to have both dedicated and context-dependent modulatory elements. Identifying modulatory subcircuits and understanding their molecular machinery is a major challenge for the sleep field. Previously, we identified 25 sleep-regulating microRNAs in Drosophila melanogaster, including the developmentally important microRNA bantam. Here we show that bantam acts in the adult to promote early nighttime sleep through a population of glutamatergic neurons that is intimately involved in applying contextual information to behaviors, the γ5β'2a/β'2mp/β'2mp_bilateral Mushroom Body Output Neurons (MBONs). Calcium imaging revealed that bantam inhibits the activity of these cells during the early night, but not the day. Blocking synaptic transmission in these MBONs rescued the effect of bantam knockdown. This suggests bantam promotes early night sleep via inhibition of the γ5β'2a/β'2mp/β'2mp_bilateral MBONs. RNAseq identifies Kelch and CCHamide-2 receptor as possible mediators, establishing a new role for bantam as an active regulator of sleep and neural activity in the adult fly.
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Affiliation(s)
- Michael Hobin
- Department of Biology, Volen National Center for Complex Systems, Brandeis University, Waltham, MA 02454-9110, USA
| | - Katherine Dorfman
- Department of Biology, Volen National Center for Complex Systems, Brandeis University, Waltham, MA 02454-9110, USA
| | - Mohamed Adel
- Department of Biology, Volen National Center for Complex Systems, Brandeis University, Waltham, MA 02454-9110, USA
| | - Emmanuel J. Rivera-Rodriguez
- Department of Biology, Volen National Center for Complex Systems, Brandeis University, Waltham, MA 02454-9110, USA
| | - Elena A. Kuklin
- Department of Biology, Volen National Center for Complex Systems, Brandeis University, Waltham, MA 02454-9110, USA
| | - Dingbang Ma
- Department of Biology, Volen National Center for Complex Systems, Brandeis University, Waltham, MA 02454-9110, USA
- Howard Hughes Medical Institute, Brandeis University, Waltham, MA 02454-9110, USA
| | - Leslie C. Griffith
- Department of Biology, Volen National Center for Complex Systems, Brandeis University, Waltham, MA 02454-9110, USA
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Adel M, Chen N, Zhang Y, Reed ML, Quasney C, Griffith LC. Pairing-Dependent Plasticity in a Dissected Fly Brain Is Input-Specific and Requires Synaptic CaMKII Enrichment and Nighttime Sleep. J Neurosci 2022; 42:4297-4310. [PMID: 35474278 PMCID: PMC9145224 DOI: 10.1523/jneurosci.0144-22.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 03/23/2022] [Accepted: 04/19/2022] [Indexed: 11/21/2022] Open
Abstract
In Drosophila, in vivo functional imaging studies revealed that associative memory formation is coupled to a cascade of neural plasticity events in distinct compartments of the mushroom body (MB). In-depth investigation of the circuit dynamics, however, will require an ex vivo model that faithfully mirrors these events to allow direct manipulations of circuit elements that are inaccessible in the intact fly. The current ex vivo models have been able to reproduce the fundamental plasticity of aversive short-term memory, a potentiation of the MB intrinsic neuron (Kenyon cells [KCs]) responses after artificial learning ex vivo However, this potentiation showed different localization and encoding properties from those reported in vivo and failed to generate the previously reported suppression plasticity in the MB output neurons (MBONs). Here, we develop an ex vivo model using the female Drosophila brain that recapitulates behaviorally evoked plasticity in the KCs and MBONs. We demonstrate that this plasticity accurately localizes to the MB α'3 compartment and is encoded by a coincidence between KC activation and dopaminergic input. The formed plasticity is input-specific, requiring pairing of the conditioned stimulus and unconditioned stimulus pathways; hence, we name it pairing-dependent plasticity. Pairing-dependent plasticity formation requires an intact CaMKII gene and is blocked by previous-night sleep deprivation but is rescued by rebound sleep. In conclusion, we show that our ex vivo preparation recapitulates behavioral and imaging results from intact animals and can provide new insights into mechanisms of memory formation at the level of molecules, circuits, and brain state.SIGNIFICANCE STATEMENT The mammalian ex vivo LTP model enabled in-depth investigation of the hippocampal memory circuit. We develop a parallel model to study the Drosophila mushroom body (MB) memory circuit. Pairing activation of the conditioned stimulus and unconditioned stimulus pathways in dissected brains induces a potentiation pairing-dependent plasticity (PDP) in the axons of α'β' Kenyon cells and a suppression PDP in the dendrites of their postsynaptic MB output neurons, localized in the MB α'3 compartment. This PDP is input-specific and requires the 3' untranslated region of CaMKII Interestingly, ex vivo PDP carries information about the animal's experience before dissection; brains from sleep-deprived animals fail to form PDP, whereas those from animals who recovered 2 h of their lost sleep form PDP.
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Affiliation(s)
- Mohamed Adel
- Department of Biology and Volen National Center for Complex Systems, Brandeis University, Waltham, Massachusetts 02454-9110
| | - Nannan Chen
- Department of Biology and Volen National Center for Complex Systems, Brandeis University, Waltham, Massachusetts 02454-9110
| | - Yunpeng Zhang
- Department of Biology and Volen National Center for Complex Systems, Brandeis University, Waltham, Massachusetts 02454-9110
| | - Martha L Reed
- Department of Biology and Volen National Center for Complex Systems, Brandeis University, Waltham, Massachusetts 02454-9110
| | - Christina Quasney
- Department of Biology and Volen National Center for Complex Systems, Brandeis University, Waltham, Massachusetts 02454-9110
| | - Leslie C Griffith
- Department of Biology and Volen National Center for Complex Systems, Brandeis University, Waltham, Massachusetts 02454-9110
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Chen N, Zhang Y, Adel M, Kuklin EA, Reed ML, Mardovin JD, Bakthavachalu B, VijayRaghavan K, Ramaswami M, Griffith LC. Local translation provides the asymmetric distribution of CaMKII required for associative memory formation. Curr Biol 2022; 32:2730-2738.e5. [PMID: 35545085 DOI: 10.1016/j.cub.2022.04.047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 03/18/2022] [Accepted: 04/14/2022] [Indexed: 10/18/2022]
Abstract
How compartment-specific local proteomes are generated and maintained is inadequately understood, particularly in neurons, which display extreme asymmetries. Here we show that local enrichment of Ca2+/calmodulin-dependent protein kinase II (CaMKII) in axons of Drosophila mushroom body neurons is necessary for cellular plasticity and associative memory formation. Enrichment is achieved via enhanced axoplasmic translation of CaMKII mRNA, through a mechanism requiring the RNA-binding protein Mub and a 23-base Mub-recognition element in the CaMKII 3' UTR. Perturbation of either dramatically reduces axonal, but not somatic, CaMKII protein without altering the distribution or amount of mRNA in vivo, and both are necessary and sufficient to enhance axonal translation of reporter mRNA. Together, these data identify elevated levels of translation of an evenly distributed mRNA as a novel strategy for generating subcellular biochemical asymmetries. They further demonstrate the importance of distributional asymmetry in the computational and biological functions of neurons.
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Affiliation(s)
- Nannan Chen
- Department of Biology, Volen National Center for Complex Systems, Brandeis University, 415 South Street, Waltham, MA 02454-9110, USA
| | - Yunpeng Zhang
- Department of Biology, Volen National Center for Complex Systems, Brandeis University, 415 South Street, Waltham, MA 02454-9110, USA
| | - Mohamed Adel
- Department of Biology, Volen National Center for Complex Systems, Brandeis University, 415 South Street, Waltham, MA 02454-9110, USA
| | - Elena A Kuklin
- Department of Biology, Volen National Center for Complex Systems, Brandeis University, 415 South Street, Waltham, MA 02454-9110, USA
| | - Martha L Reed
- Department of Biology, Volen National Center for Complex Systems, Brandeis University, 415 South Street, Waltham, MA 02454-9110, USA
| | - Jacob D Mardovin
- Department of Biology, Volen National Center for Complex Systems, Brandeis University, 415 South Street, Waltham, MA 02454-9110, USA
| | - Baskar Bakthavachalu
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bellary Road, Bangalore 560065, India; School of Basic Science, Indian Institute of Technology Mandi, Mandi, India
| | - K VijayRaghavan
- National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bellary Road, Bangalore 560065, India; School of Basic Science, Indian Institute of Technology Mandi, Mandi, India
| | - Mani Ramaswami
- Trinity College Institute of Neuroscience, School of Genetics and Microbiology and School of Natural Sciences, Trinity College Dublin, Dublin 2, Ireland; National Centre for Biological Sciences, Tata Institute of Fundamental Research, Bellary Road, Bangalore 560065, India; School of Basic Science, Indian Institute of Technology Mandi, Mandi, India
| | - Leslie C Griffith
- Department of Biology, Volen National Center for Complex Systems, Brandeis University, 415 South Street, Waltham, MA 02454-9110, USA.
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Saitoe M, Naganos S, Miyashita T, Matsuno M, Ueno K. A non-canonical on-demand dopaminergic transmission underlying olfactory aversive learning. Neurosci Res 2021; 178:1-9. [PMID: 34973292 DOI: 10.1016/j.neures.2021.12.008] [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: 06/02/2021] [Revised: 11/16/2021] [Accepted: 12/27/2021] [Indexed: 10/19/2022]
Abstract
Dopamine (DA) is involved in various brain functions including associative learning. However, it is unclear how a small number of DA neurons appropriately regulates various brain functions. DA neurons have a large number of release sites and release DA non-specifically to a large number of target neurons in the projection area in response to the activity of DA neurons. In contrast to this "broad transmission", recent studies in Drosophila ex vivo functional imaging studies have identified "on-demand transmission" that occurs independent on activity of DA neurons and releases DA specifically onto the target neurons that have produced carbon monoxide (CO) as a retrograde signal for DA release. Whereas broad transmission modulates the global function of the target area, on-demand transmission is suitable for modulating the function of specific circuits, neurons, or synapses. In Drosophila olfactory aversive conditioning, odor and shock information are associated in the brain region called mushroom body (MB) to form olfactory aversive memory. It has been suggested that DA neurons projecting to the MB mediate the transmission of shock information and reinforcement simultaneously. However, the circuit model based on on-demand transmission proposes that transmission of shock information and reinforcement are mediated by distinct neural mechanisms; while shock transmission is glutamatergic, DA neurons mediates reinforcement. On-demand transmission provides mechanical insights into how DA neurons regulate various brain functions.
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Affiliation(s)
- Minoru Saitoe
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya, Tokyo, 156-8506, Japan.
| | - Shintaro Naganos
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya, Tokyo, 156-8506, Japan
| | - Tomoyuki Miyashita
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya, Tokyo, 156-8506, Japan
| | - Motomi Matsuno
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya, Tokyo, 156-8506, Japan
| | - Kohei Ueno
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya, Tokyo, 156-8506, Japan
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Consolidation and maintenance of long-term memory involve dual functions of the developmental regulator Apterous in clock neurons and mushroom bodies in the Drosophila brain. PLoS Biol 2021; 19:e3001459. [PMID: 34860826 PMCID: PMC8641882 DOI: 10.1371/journal.pbio.3001459] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 10/25/2021] [Indexed: 11/23/2022] Open
Abstract
Memory is initially labile but can be consolidated into stable long-term memory (LTM) that is stored in the brain for extended periods. Despite recent progress, the molecular and cellular mechanisms underlying the intriguing neurobiological processes of LTM remain incompletely understood. Using the Drosophila courtship conditioning assay as a memory paradigm, here, we show that the LIM homeodomain (LIM-HD) transcription factor Apterous (Ap), which is known to regulate various developmental events, is required for both the consolidation and maintenance of LTM. Interestingly, Ap is involved in these 2 memory processes through distinct mechanisms in different neuronal subsets in the adult brain. Ap and its cofactor Chip (Chi) are indispensable for LTM maintenance in the Drosophila memory center, the mushroom bodies (MBs). On the other hand, Ap plays a crucial role in memory consolidation in a Chi-independent manner in pigment dispersing factor (Pdf)-containing large ventral–lateral clock neurons (l-LNvs) that modulate behavioral arousal and sleep. Since disrupted neurotransmission and electrical silencing in clock neurons impair memory consolidation, Ap is suggested to contribute to the stabilization of memory by ensuring the excitability of l-LNvs. Indeed, ex vivo imaging revealed that a reduced function of Ap, but not Chi, results in exaggerated Cl− responses to the inhibitory neurotransmitter gamma-aminobutyric acid (GABA) in l-LNvs, indicating that wild-type (WT) Ap maintains high l-LNv excitability by suppressing the GABA response. Consistently, enhancing the excitability of l-LNvs by knocking down GABAA receptors compensates for the impaired memory consolidation in ap null mutants. Overall, our results revealed unique dual functions of the developmental regulator Ap for LTM consolidation in clock neurons and LTM maintenance in MBs. A neurogenetic study using Drosophila reveals that the centrally expressed LIM-homeodomain transcription factor Apterous plays a crucial neuron-type-dependent role in two different memory processes - consolidation and maintenance of long-term memory.
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9
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Adel M, Griffith LC. The Role of Dopamine in Associative Learning in Drosophila: An Updated Unified Model. Neurosci Bull 2021; 37:831-852. [PMID: 33779893 PMCID: PMC8192648 DOI: 10.1007/s12264-021-00665-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 09/25/2020] [Indexed: 10/21/2022] Open
Abstract
Learning to associate a positive or negative experience with an unrelated cue after the presentation of a reward or a punishment defines associative learning. The ability to form associative memories has been reported in animal species as complex as humans and as simple as insects and sea slugs. Associative memory has even been reported in tardigrades [1], species that diverged from other animal phyla 500 million years ago. Understanding the mechanisms of memory formation is a fundamental goal of neuroscience research. In this article, we work on resolving the current contradictions between different Drosophila associative memory circuit models and propose an updated version of the circuit model that predicts known memory behaviors that current models do not. Finally, we propose a model for how dopamine may function as a reward prediction error signal in Drosophila, a dopamine function that is well-established in mammals but not in insects [2, 3].
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Affiliation(s)
- Mohamed Adel
- Department of Biology, Volen National Center for Complex Systems and National Center for Behavioral Genomics, Brandeis University, Waltham, MA, 02454-9110, USA.
| | - Leslie C Griffith
- Department of Biology, Volen National Center for Complex Systems and National Center for Behavioral Genomics, Brandeis University, Waltham, MA, 02454-9110, USA
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10
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Gold AR, Glanzman DL. The central importance of nuclear mechanisms in the storage of memory. Biochem Biophys Res Commun 2021; 564:103-113. [PMID: 34020774 DOI: 10.1016/j.bbrc.2021.04.125] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 04/28/2021] [Accepted: 04/28/2021] [Indexed: 12/14/2022]
Abstract
The neurobiological nature of the memory trace (engram) remains controversial. The most widely accepted hypothesis at present is that long-term memory is stored as stable, learning-induced changes in synaptic connections. This hypothesis, the synaptic plasticity hypothesis of memory, is supported by extensive experimental data gathered from over 50 years of research. Nonetheless, there are important mnemonic phenomena that the synaptic plasticity hypothesis cannot, or cannot readily, account for. Furthermore, recent work indicates that epigenetic and genomic mechanisms play heretofore underappreciated roles in memory. Here, we critically assess the evidence that supports the synaptic plasticity hypothesis and discuss alternative non-synaptic, nuclear mechanisms of memory storage, including DNA methylation and retrotransposition. We argue that long-term encoding of memory is mediated by nuclear processes; synaptic plasticity, by contrast, represents a means of relatively temporary memory storage. In addition, we propose that memories are evaluated for their mnemonic significance during an initial period of synaptic storage; if assessed as sufficiently important, the memories then undergo nuclear encoding.
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Affiliation(s)
- Adam R Gold
- Behavioral Neuroscience Program, Department of Psychology, University of California, Los Angeles, Los Angeles, CA, 90095, USA.
| | - David L Glanzman
- Department of Integrative Biology & Physiology, UCLA College, University of California, Los Angeles, Los Angeles, CA, 90095, USA; Department of Neurobiology, David Geffen School of Medicine at UCLA, University of California, Los Angeles, Los Angeles, CA, 90095, USA; Integrative Center for Learning and Memory, Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, 90095, USA.
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11
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Hidalgo S, Campusano JM, Hodge JJL. The Drosophila ortholog of the schizophrenia-associated CACNA1A and CACNA1B voltage-gated calcium channels regulate memory, sleep and circadian rhythms. Neurobiol Dis 2021; 155:105394. [PMID: 34015490 DOI: 10.1016/j.nbd.2021.105394] [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: 01/26/2021] [Revised: 05/10/2021] [Accepted: 05/14/2021] [Indexed: 01/04/2023] Open
Abstract
Schizophrenia exhibits up to 80% heritability. A number of genome wide association studies (GWAS) have repeatedly shown common variants in voltage-gated calcium (Cav) channel genes CACNA1C, CACNA1I and CACNA1G have a major contribution to the risk of the disease. More recently, studies using whole exome sequencing have also found that CACNA1B (Cav2.2 N-type) deletions and rare disruptive variants in CACNA1A (Cav2.1 P/Q-type) are associated with schizophrenia. The negative symptoms of schizophrenia include behavioural defects such as impaired memory, sleep and circadian rhythms. It is not known how variants in schizophrenia-associated genes contribute to cognitive and behavioural symptoms, thus hampering the development of treatment for schizophrenia symptoms. In order to address this knowledge gap, we studied behavioural phenotypes in a number of loss of function mutants for the Drosophila ortholog of the Cav2 gene family called cacophony (cac). cac mutants showed several behavioural features including decreased night-time sleep and hyperactivity similar to those reported in human patients. The change in timing of sleep-wake cycles suggested disrupted circadian rhythms, with the loss of night-time sleep being caused by loss of cac just in the circadian clock neurons. These animals also showed a reduction in rhythmic circadian behaviour a phenotype that also could be mapped to the central clock. Furthermore, reduction of cac just in the clock resulted in a lengthening of the 24 h period. In order to understand how loss of Cav2 function may lead to cognitive deficits and underlying cellular pathophysiology we targeted loss of function of cac to the memory centre of the fly, called the mushroom bodies (MB). This manipulation was sufficient to cause reduction in both short- and intermediate-term associative memory. Memory impairment was accompanied by a decrease in Ca2+ transients in response to a depolarizing stimulus, imaged in the MB presynaptic terminals. This work shows loss of cac Cav2 channel function alone causes a number of cognitive and behavioural deficits and underlying reduced neuronal Ca2+ transients, establishing Drosophila as a high-throughput in vivo genetic model to study the Cav channel pathophysiology related to schizophrenia.
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Affiliation(s)
- Sergio Hidalgo
- School of Physiology, Pharmacology and Neuroscience, Faculty of Life Science, University of Bristol, UK; Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Chile
| | - Jorge M Campusano
- Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Chile
| | - James J L Hodge
- School of Physiology, Pharmacology and Neuroscience, Faculty of Life Science, University of Bristol, UK.
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12
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Hidalgo S, Campusano JM, Hodge JJL. Assessing olfactory, memory, social and circadian phenotypes associated with schizophrenia in a genetic model based on Rim. Transl Psychiatry 2021; 11:292. [PMID: 34001859 PMCID: PMC8128896 DOI: 10.1038/s41398-021-01418-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2020] [Revised: 04/22/2021] [Accepted: 04/30/2021] [Indexed: 02/04/2023] Open
Abstract
Schizophrenia shows high heritability and several of the genes associated with this disorder are involved in calcium (Ca2+) signalling and synaptic function. One of these is the Rab-3 interacting molecule-1 (RIM1), which has recently been associated with schizophrenia by Genome Wide Association Studies (GWAS). However, its contribution to the pathophysiology of this disorder remains unexplored. In this work, we use Drosophila mutants of the orthologue of RIM1, Rim, to model some aspects of the classical and non-classical symptoms of schizophrenia. Rim mutants showed several behavioural features relevant to schizophrenia including social distancing and altered olfactory processing. These defects were accompanied by reduced evoked Ca2+ influx and structural changes in the presynaptic terminals sent by the primary olfactory neurons to higher processing centres. In contrast, expression of Rim-RNAi in the mushroom bodies (MBs), the main memory centre in flies, spared learning and memory suggesting a differential role of Rim in different synapses. Circadian deficits have been reported in schizophrenia. We observed circadian locomotor activity deficits in Rim mutants, revealing a role of Rim in the pacemaker ventral lateral clock neurons (LNvs). These changes were accompanied by impaired day/night remodelling of dorsal terminal synapses from a subpopulation of LNvs and impaired day/night release of the circadian neuropeptide pigment dispersing factor (PDF) from these terminals. Lastly, treatment with the commonly used antipsychotic haloperidol rescued Rim locomotor deficits to wildtype. This work characterises the role of Rim in synaptic functions underlying behaviours disrupted in schizophrenia.
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Affiliation(s)
- Sergio Hidalgo
- Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
- School of Physiology, Pharmacology and Neuroscience, Faculty of Life Science, University of Bristol, Bristol, UK
| | - Jorge M Campusano
- Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile.
| | - James J L Hodge
- School of Physiology, Pharmacology and Neuroscience, Faculty of Life Science, University of Bristol, Bristol, UK.
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13
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Morstein J, Höfler D, Ueno K, Jurss JW, Walvoord RR, Bruemmer KJ, Rezgui SP, Brewer TF, Saitoe M, Michel BW, Chang CJ. Ligand-Directed Approach to Activity-Based Sensing: Developing Palladacycle Fluorescent Probes That Enable Endogenous Carbon Monoxide Detection. J Am Chem Soc 2020; 142:15917-15930. [DOI: 10.1021/jacs.0c06405] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
| | | | - Kohei Ueno
- Tokyo Metropolitan Institute of Medical Science, Tokyo 1568506, Japan
| | | | | | | | - Samir P. Rezgui
- Department of Chemistry and Biochemistry, University of Denver, Denver, Colorado 80210, United States
| | | | - Minoru Saitoe
- Tokyo Metropolitan Institute of Medical Science, Tokyo 1568506, Japan
| | - Brian W. Michel
- Department of Chemistry and Biochemistry, University of Denver, Denver, Colorado 80210, United States
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Carbon Monoxide, a Retrograde Messenger Generated in Postsynaptic Mushroom Body Neurons, Evokes Noncanonical Dopamine Release. J Neurosci 2020; 40:3533-3548. [PMID: 32253360 DOI: 10.1523/jneurosci.2378-19.2020] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 02/12/2020] [Accepted: 03/19/2020] [Indexed: 02/06/2023] Open
Abstract
Dopaminergic neurons innervate extensive areas of the brain and release dopamine (DA) onto a wide range of target neurons. However, DA release is also precisely regulated. In Drosophila melanogaster brain explant preparations, DA is released specifically onto α3/α'3 compartments of mushroom body (MB) neurons that have been coincidentally activated by cholinergic and glutamatergic inputs. The mechanism for this precise release has been unclear. Here we found that coincidentally activated MB neurons generate carbon monoxide (CO), which functions as a retrograde signal evoking local DA release from presynaptic terminals. CO production depends on activity of heme oxygenase in postsynaptic MB neurons, and CO-evoked DA release requires Ca2+ efflux through ryanodine receptors in DA terminals. CO is only produced in MB areas receiving coincident activation, and removal of CO using scavengers blocks DA release. We propose that DA neurons use two distinct modes of transmission to produce global and local DA signaling.SIGNIFICANCE STATEMENT Dopamine (DA) is needed for various higher brain functions, including memory formation. However, DA neurons form extensive synaptic connections, while memory formation requires highly specific and localized DA release. Here we identify a mechanism through which DA release from presynaptic terminals is controlled by postsynaptic activity. Postsynaptic neurons activated by cholinergic and glutamatergic inputs generate carbon monoxide, which acts as a retrograde messenger inducing presynaptic DA release. Released DA is required for memory-associated plasticity. Our work identifies a novel mechanism that restricts DA release to the specific postsynaptic sites that require DA during memory formation.
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15
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Boto T, Stahl A, Tomchik SM. Cellular and circuit mechanisms of olfactory associative learning in Drosophila. J Neurogenet 2020; 34:36-46. [PMID: 32043414 DOI: 10.1080/01677063.2020.1715971] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Recent years have witnessed significant progress in understanding how memories are encoded, from the molecular to the cellular and the circuit/systems levels. With a good compromise between brain complexity and behavioral sophistication, the fruit fly Drosophila melanogaster is one of the preeminent animal models of learning and memory. Here we review how memories are encoded in Drosophila, with a focus on short-term memory and an eye toward future directions. Forward genetic screens have revealed a large number of genes and transcripts necessary for learning and memory, some acting cell-autonomously. Further, the relative numerical simplicity of the fly brain has enabled the reverse engineering of learning circuits with remarkable precision, in some cases ascribing behavioral phenotypes to single neurons. Functional imaging and physiological studies have localized and parsed the plasticity that occurs during learning at some of the major loci. Connectomics projects are significantly expanding anatomical knowledge of the nervous system, filling out the roadmap for ongoing functional/physiological and behavioral studies, which are being accelerated by simultaneous tool development. These developments have provided unprecedented insight into the fundamental neural principles of learning, and lay the groundwork for deep understanding in the near future.
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Affiliation(s)
- Tamara Boto
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL, USA
| | - Aaron Stahl
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL, USA
| | - Seth M Tomchik
- Department of Neuroscience, The Scripps Research Institute, Jupiter, FL, USA
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Horiuchi J. Recurrent loops: Incorporating prediction error and semantic/episodic theories into Drosophila associative memory models. GENES BRAIN AND BEHAVIOR 2019; 18:e12567. [PMID: 30891930 PMCID: PMC6900151 DOI: 10.1111/gbb.12567] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 02/27/2019] [Accepted: 03/16/2019] [Indexed: 12/01/2022]
Abstract
In 2003, Martin Heisenberg et al. presented a model of how associative memories could be encoded and stored in the insect brain. This model was extremely influential in the Drosophila memory field, but did not incorporate several important mammalian concepts, including ideas of separate episodic and semantic types of memory and prediction error hypotheses. In addition, at that time, the concept of memory traces recurrently entering and exiting the mushroom bodies, brain areas where associative memories are formed and stored, was unknown. In this review, I present a simple updated model incorporating these ideas, which may be useful for future studies.
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Affiliation(s)
- Junjiro Horiuchi
- Department of higher brain functions and dementias, Tokyo Metropolitan Institute of Medical Science, Tokyo, Japan
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17
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Dopamine release in mushroom bodies of the honey bee (Apis mellifera L.) in response to aversive stimulation. Sci Rep 2018; 8:16277. [PMID: 30389979 PMCID: PMC6214997 DOI: 10.1038/s41598-018-34460-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 09/20/2018] [Indexed: 01/13/2023] Open
Abstract
In Drosophila melanogaster, aversive (electric shock) stimuli have been shown to activate subpopulations of dopaminergic neurons with terminals in the mushroom bodies (MBs) of the brain. While there is compelling evidence that dopamine (DA)-induced synaptic plasticity underpins the formation of aversive memories in insects, the mechanisms involved have yet to be fully resolved. Here we take advantage of the accessibility of MBs in the brain of the honey bee to examine, using fast scan cyclic voltammetry, the kinetics of DA release and reuptake in vivo in response to electric shock, and to investigate factors that modulate the release of this amine. DA increased transiently in the MBs in response to electric shock stimuli. The magnitude of release varied depending on stimulus duration and intensity, and a strong correlation was identified between DA release and the intensity of behavioural responses to shock. With repeated stimulation, peak DA levels increased. However, the amount of DA released on the first stimulation pulse typically exceeded that evoked by subsequent pulses. No signal was detected in response to odour alone. Interestingly, however, if odour presentation was paired with electric shock, DA release was enhanced. These results set the stage for analysing the mechanisms that modulate DA release in the MBs of the bee.
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18
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Sato S, Ueno K, Saitoe M, Sakai T. Synaptic depression induced by postsynaptic cAMP production in the Drosophila mushroom body calyx. J Physiol 2018; 596:2447-2461. [PMID: 29659025 DOI: 10.1113/jp275799] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 04/06/2018] [Indexed: 12/15/2022] Open
Abstract
KEY POINTS Synaptic potentiation in Drosophila is observed at cholinergic synapses between antennal lobe (AL) and mushroom body (MB) neurons in the adult brain; however, depression at the AL-MB synapses has not yet been identified. By ex vivo Ca2+ imaging in an isolated cultured Drosophila brain, we found novel activity-dependent depression at the AL-MB synapses. The degree of Ca2+ responses after repetitive AL stimulation is significantly reduced in the dendritic region of MB neurons (calyx) compared with those before AL stimulation, and this reduction of Ca2+ responses remains for at least 30 min. The expression of rutabaga, which encodes Ca2+ /calmodulin-dependent adenylyl cyclase, is essential in the MB neurons for the reduction of Ca2+ responses in the calyx. Our study reveals that elevation of cAMP production in the calyx during repetitive AL stimulation induces the depression at the AL-MB synapses. ABSTRACT Synaptic plasticity has been studied to reveal the molecular and cellular mechanisms of associative and non-associative learning. The fruit fly Drosophila melanogaster can be used to identify the molecular mechanisms of synaptic plasticity because vast genetic information or tools are available. Here, by ex vivo Ca2+ imaging of an isolated cultured Drosophila brain, we examined the novel activity-dependent synaptic depression between the projection neurons of the antennal lobe (AL) and mushroom body (MB). Ex vivo Ca2+ imaging analysis revealed that electrical stimulation of AL elicits Ca2+ responses in the dendritic (calyx) and axonal (α lobe) regions of MB neurons, and the responses are reduced after repetitive AL stimulation. Since the cAMP signalling pathway plays an important role in synaptic plasticity in invertebrates and vertebrates, we examined whether the reduction of Ca2+ responses is also regulated by the cAMP signalling pathway. The expression of rutabaga (rut), which encodes Ca2+ /calmodulin-dependent adenylyl cyclase, was essential for the reduction of Ca2+ responses in the calyx and α lobe. Furthermore, imaging analysis using a fluorescence resonance energy transfer-based cAMP indicator revealed that the cAMP level increased in the wild-type calyx during repetitive AL stimulation, whereas it decreased in rut1 mutant flies with a loss-of-function mutation of rut. Thus, our study suggests that an increase in postsynaptic cAMP level during repetitive AL stimulation contributes to the attenuation of inputs at AL-MB synapses.
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Affiliation(s)
- Shoma Sato
- Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minami-osawa, Hachioji, Tokyo, 1920372, Japan
| | - Kohei Ueno
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 1568506, Japan
| | - Minoru Saitoe
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo, 1568506, Japan
| | - Takaomi Sakai
- Department of Biological Sciences, Tokyo Metropolitan University, 1-1 Minami-osawa, Hachioji, Tokyo, 1920372, Japan
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19
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A Drosophila ex vivo model of olfactory appetitive learning. Sci Rep 2017; 7:17725. [PMID: 29255174 PMCID: PMC5735177 DOI: 10.1038/s41598-017-17955-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 12/04/2017] [Indexed: 01/07/2023] Open
Abstract
During olfactory appetitive learning, animals associate an odor, or conditioned stimulus (CS), with an unconditioned stimulus (US), often a sugar reward. This association induces feeding behavior, a conditioned response (CR), upon subsequent exposure to the CS. In this study, we developed a model of this behavior in isolated Drosophila brains. Artificial activation of neurons expressing the Gr5a sugar-responsive gustatory receptor (Gr5a GRNs) induces feeding behavior in starved flies. Consistent with this, we find that in dissected brains, activation of Gr5a GRNs induces Ca2+ transients in motor neurons, MN11 + 12, required for ingestion. Significantly, activation of Gr5a GRNs can substitute for presentation of sugar rewards during olfactory appetitive learning. Similarly, in dissected brains, coincident stimulation of Gr5a GRNs and the antennal lobe (AL), which processes olfactory information, results in increased Ca2+ influx into MN11 + 12 cells upon subsequent AL stimulation. Importantly, olfactory appetitive associations are not formed in satiated flies. Likewise, AL-evoked Ca2+ transients in MN11 + 12 are not produced in ex vivo brains from satiated flies. Our results suggest that a starved/satiated state is maintained in dissected brains, and that this ex vivo system will be useful for identification of neural networks involved in olfactory appetitive learning.
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Ueno K, Suzuki E, Naganos S, Ofusa K, Horiuchi J, Saitoe M. Coincident postsynaptic activity gates presynaptic dopamine release to induce plasticity in Drosophila mushroom bodies. eLife 2017; 6. [PMID: 28117664 PMCID: PMC5262376 DOI: 10.7554/elife.21076] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Accepted: 01/11/2017] [Indexed: 11/13/2022] Open
Abstract
Simultaneous stimulation of the antennal lobes (ALs) and the ascending fibers of the ventral nerve cord (AFV), two sensory inputs to the mushroom bodies (MBs), induces long-term enhancement (LTE) of subsequent AL-evoked MB responses. LTE induction requires activation of at least three signaling pathways to the MBs, mediated by nicotinic acetylcholine receptors (nAChRs), NMDA receptors (NRs), and D1 dopamine receptors (D1Rs). Here, we demonstrate that inputs from the AL are transmitted to the MBs through nAChRs, and inputs from the AFV are transmitted by NRs. Dopamine signaling occurs downstream of both nAChR and NR activation, and requires simultaneous stimulation of both pathways. Dopamine release requires the activity of the rutabaga adenylyl cyclase in postsynaptic MB neurons, and release is restricted to MB neurons that receive coincident stimulation. Our results indicate that postsynaptic activity can gate presynaptic dopamine release to regulate plasticity.
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Affiliation(s)
- Kohei Ueno
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, Setagaya, Japan
| | - Ema Suzuki
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, Setagaya, Japan
| | - Shintaro Naganos
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, Setagaya, Japan
| | - Kyoko Ofusa
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, Setagaya, Japan
| | - Junjiro Horiuchi
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, Setagaya, Japan
| | - Minoru Saitoe
- Learning and Memory Project, Tokyo Metropolitan Institute of Medical Science, Setagaya, Japan
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21
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Hirano Y, Ihara K, Masuda T, Yamamoto T, Iwata I, Takahashi A, Awata H, Nakamura N, Takakura M, Suzuki Y, Horiuchi J, Okuno H, Saitoe M. Shifting transcriptional machinery is required for long-term memory maintenance and modification in Drosophila mushroom bodies. Nat Commun 2016; 7:13471. [PMID: 27841260 PMCID: PMC5114576 DOI: 10.1038/ncomms13471] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2016] [Accepted: 10/06/2016] [Indexed: 01/08/2023] Open
Abstract
Accumulating evidence suggests that transcriptional regulation is required for maintenance of long-term memories (LTMs). Here we characterize global transcriptional and epigenetic changes that occur during LTM storage in the Drosophila mushroom bodies (MBs), structures important for memory. Although LTM formation requires the CREB transcription factor and its coactivator, CBP, subsequent early maintenance requires CREB and a different coactivator, CRTC. Late maintenance becomes CREB independent and instead requires the transcription factor Bx. Bx expression initially depends on CREB/CRTC activity, but later becomes CREB/CRTC independent. The timing of the CREB/CRTC early maintenance phase correlates with the time window for LTM extinction and we identify different subsets of CREB/CRTC target genes that are required for memory maintenance and extinction. Furthermore, we find that prolonging CREB/CRTC-dependent transcription extends the time window for LTM extinction. Our results demonstrate the dynamic nature of stored memory and its regulation by shifting transcription systems in the MBs. Transcriptional regulation is necessary for maintaining long-term memories (LTM) but the mechanistic details are not completely defined. Here the authors identify transcriptional machinery and histone modifiers required for LTM maintenance in Drosophila and show that transcriptional regulation for LTM maintenance is distinct from that for LTM formation.
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Affiliation(s)
- Yukinori Hirano
- SK Project, Medical Innovation Center, Kyoto University Graduate School of Medicine, 53 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan.,Japan Science and Technology Agency, PRESTO, 4-4-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
| | - Kunio Ihara
- Center of Gene Research, Nagoya University, Huro-cho, Chikusa-ku, Nagoya 464-8602, Japan
| | - Tomoko Masuda
- Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya, Tokyo 156-0057, Japan
| | - Takuya Yamamoto
- Center for iPS Cell Research and Application, Department of Reprogramming Science, Kyoto University, 53 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, Kyoto 606-8507, Japan.,Institute for Integrated Cell-Material Sciences (WPI-iCeMS), Kyoto University, 53 Shogoin Kawahara-cho, Sakyo-ku, Kyoto, Kyoto 606-8507, Japan.,AMED-CREST, AMED 1-7-1 Otemach, Chiyodaku, Tokyo 100-0004, Japan
| | - Ikuko Iwata
- SK Project, Medical Innovation Center, Kyoto University Graduate School of Medicine, 53 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Aya Takahashi
- SK Project, Medical Innovation Center, Kyoto University Graduate School of Medicine, 53 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Hiroko Awata
- SK Project, Medical Innovation Center, Kyoto University Graduate School of Medicine, 53 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Naosuke Nakamura
- SK Project, Medical Innovation Center, Kyoto University Graduate School of Medicine, 53 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan.,Kyoto Sangyo University, Motoyama, Kamigamo, Kita-ku, Kyoto City 603-8555, Japan
| | - Mai Takakura
- SK Project, Medical Innovation Center, Kyoto University Graduate School of Medicine, 53 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Yusuke Suzuki
- SK Project, Medical Innovation Center, Kyoto University Graduate School of Medicine, 53 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Junjiro Horiuchi
- Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya, Tokyo 156-0057, Japan
| | - Hiroyuki Okuno
- SK Project, Medical Innovation Center, Kyoto University Graduate School of Medicine, 53 Shogoin Kawahara-cho, Sakyo-ku, Kyoto 606-8507, Japan
| | - Minoru Saitoe
- Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya, Tokyo 156-0057, Japan
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22
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Naganos S, Ueno K, Horiuchi J, Saitoe M. Learning defects in Drosophila growth restricted chico mutants are caused by attenuated adenylyl cyclase activity. Mol Brain 2016; 9:37. [PMID: 27048332 PMCID: PMC4822261 DOI: 10.1186/s13041-016-0217-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 03/29/2016] [Indexed: 11/10/2022] Open
Abstract
Background Reduced insulin/insulin-like growth factor signaling (IIS) is a major cause of symmetrical intrauterine growth retardation (IUGR), an impairment in cell proliferation during prenatal development that results in global growth defects and mental retardation. In Drosophila, chico encodes the only insulin receptor substrate. Similar to other animal models of IUGR, chico mutants have defects in global growth and associative learning. However, the physiological and molecular bases of learning defects caused by chico mutations, and by symmetrical IUGR, are not clear. Results In this study, we found that chico mutations impair memory-associated synaptic plasticity in the mushroom bodies (MBs), neural centers for olfactory learning. Mutations in chico reduce expression of the rutabaga-type adenylyl cyclase (rut), leading to decreased cAMP synthesis in the MBs. Expressing a rut+ transgene in the MBs restores memory-associated plasticity and olfactory associative learning in chico mutants, without affecting growth. Thus chico mutations disrupt olfactory learning, at least in part, by reducing cAMP signaling in the MBs. Conclusions Our results suggest that some cognitive defects associated with reduced IIS may occur, independently of developmental defects, from acute reductions in cAMP signaling.
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Affiliation(s)
- Shintaro Naganos
- Tokyo Metropolitan Institute of Medical Science, 2-1-6, Kamikitazawa, Setagaya, 185-8506, Tokyo, Japan
| | - Kohei Ueno
- Tokyo Metropolitan Institute of Medical Science, 2-1-6, Kamikitazawa, Setagaya, 185-8506, Tokyo, Japan
| | - Junjiro Horiuchi
- Tokyo Metropolitan Institute of Medical Science, 2-1-6, Kamikitazawa, Setagaya, 185-8506, Tokyo, Japan
| | - Minoru Saitoe
- Tokyo Metropolitan Institute of Medical Science, 2-1-6, Kamikitazawa, Setagaya, 185-8506, Tokyo, Japan.
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23
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Silva B, Molina-Fernández C, Ugalde MB, Tognarelli EI, Angel C, Campusano JM. Muscarinic ACh Receptors Contribute to Aversive Olfactory Learning in Drosophila. Neural Plast 2015; 2015:658918. [PMID: 26380118 PMCID: PMC4562076 DOI: 10.1155/2015/658918] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2014] [Revised: 04/21/2015] [Accepted: 04/29/2015] [Indexed: 01/15/2023] Open
Abstract
The most studied form of associative learning in Drosophila consists in pairing an odorant, the conditioned stimulus (CS), with an unconditioned stimulus (US). The timely arrival of the CS and US information to a specific Drosophila brain association region, the mushroom bodies (MB), can induce new olfactory memories. Thus, the MB is considered a coincidence detector. It has been shown that olfactory information is conveyed to the MB through cholinergic inputs that activate acetylcholine (ACh) receptors, while the US is encoded by biogenic amine (BA) systems. In recent years, we have advanced our understanding on the specific neural BA pathways and receptors involved in olfactory learning and memory. However, little information exists on the contribution of cholinergic receptors to this process. Here we evaluate for the first time the proposition that, as in mammals, muscarinic ACh receptors (mAChRs) contribute to memory formation in Drosophila. Our results show that pharmacological and genetic blockade of mAChRs in MB disrupts olfactory aversive memory in larvae. This effect is not explained by an alteration in the ability of animals to respond to odorants or to execute motor programs. These results show that mAChRs in MB contribute to generating olfactory memories in Drosophila.
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Affiliation(s)
- Bryon Silva
- Laboratorio Neurogenética de la Conducta, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Alameda 340, 8331150 Santiago, Chile
| | - Claudia Molina-Fernández
- Laboratorio Neurogenética de la Conducta, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Alameda 340, 8331150 Santiago, Chile
| | - María Beatriz Ugalde
- Laboratorio Neurogenética de la Conducta, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Alameda 340, 8331150 Santiago, Chile
| | - Eduardo I. Tognarelli
- Laboratorio Neurogenética de la Conducta, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Alameda 340, 8331150 Santiago, Chile
| | - Cristian Angel
- Laboratorio Neurogenética de la Conducta, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Alameda 340, 8331150 Santiago, Chile
| | - Jorge M. Campusano
- Laboratorio Neurogenética de la Conducta, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Alameda 340, 8331150 Santiago, Chile
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Sato S, Kitamoto T, Sakai T. Modulation of innate and learned sexual behaviors by the TRP channel Painless expressed in the fruit fly brain: behavioral genetic analysis and its implications. Front Behav Neurosci 2014; 8:400. [PMID: 25520634 PMCID: PMC4251448 DOI: 10.3389/fnbeh.2014.00400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Accepted: 11/01/2014] [Indexed: 11/19/2022] Open
Abstract
Transient receptor potential (TRP) channels have attracted considerable attention because of their vital roles in primary sensory neurons, mediating responses to a wide variety of external environmental stimuli. However, much less is known about how TRP channels in the brain respond to intrinsic signals and are involved in neurophysiological processes that control complex behaviors. Painless (Pain) is the Drosophila TRP channel that was initially identified as a molecular sensor responsible for detecting noxious thermal and mechanical stimuli. Here, we review recent behavioral genetic studies demonstrating that Pain expressed in the brain plays a critical role in both innate and learned aspects of sexual behaviors. Several members of the TRP channel superfamily play evolutionarily conserved roles in sensory neurons as well as in other peripheral tissues. It is thus expected that brain TRP channels in vertebrates and invertebrates would have some common physiological functions. Studies of Pain in the Drosophila brain using a unique combination of genetics and physiological techniques should provide valuable insights into the fundamental principles concerning TRP channels expressed in the vertebrate and invertebrate brains.
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Affiliation(s)
- Shoma Sato
- Department of Biological Sciences, Tokyo Metropolitan University Hachiouji, Tokyo, Japan
| | - Toshihiro Kitamoto
- Department of Anesthesia and Pharmacology, University of Iowa Iowa City, Iowa, USA ; Interdisciplinary Graduate Programs in Genetics and Neuroscience, University of Iowa Iowa City, Iowa, USA
| | - Takaomi Sakai
- Department of Biological Sciences, Tokyo Metropolitan University Hachiouji, Tokyo, Japan
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25
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Shan Z, Cai S, Zhang T, Kuang L, Wang Q, Xiu H, Wen J, Gu H, Xu K. Effects of sevoflurane on leucine-rich repeat kinase 2-associated Drosophila model of Parkinson's disease. Mol Med Rep 2014; 11:2062-70. [PMID: 25406035 DOI: 10.3892/mmr.2014.2966] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Accepted: 09/24/2014] [Indexed: 11/05/2022] Open
Abstract
Patients with Parkinson's disease (PD) often require surgery, and therefore may receive inhalation anesthesia. However, it is currently unknown whether inhalation anesthetics affect the prognosis of the disease. Leucine‑rich repeat kinase 2 (LRRK2) genetic mutations are the most common cause of familial PD, contributing to ~39% of all cases in certain populations. The aim of the present study was to determine the effects of inhaled anesthetics on PD, by observing the influence of sevoflurane on a LRRK2‑associated Drosophila model of PD. PD transgenic Drosophila overexpressing LRRK2 were generated by crossing flies expressing an LRRK2 upstream activation sequence, with tyrosine hydroxylase (TH)‑Gal4 flies. Western blot analysis successfully verified that the transgenic Drosophila overexpressed LRRK2. Three days prior to eclosion, three genotypes of Drosophila were divided into four groups, and were exposed to air, 1, 2, or 3% sevoflurane, for 5 hours. Twenty‑four hours after the exposure, the electrophysiological activities of the projection neurons (PN) in the brains of the Drosophila were recorded using a patch clamp. The locomotor activities were tested on days 5, 10, 15, 20, 25, 30, 35 and 40 following eclosion. The frequency of miniature excitatory synaptic currents (mEPSCs) obtained from the PNs of the TH‑wild type LRRK2 (TH‑WT) Drosophila brain, following exposure to air (1.60±0.05 Hz), was lower as compared with the wild type LRRK2 (WT) (2.51±0.07 Hz) and W1118 (2.41±0.10 Hz) Drosophila. After exposure to 1, 2 and 3% sevoflurane, the frequency of mEPSCs in the brains of the TH‑WT group decreased to 0.82±0.04 Hz, 0.63±0.16 Hz and 0.55±0.04 Hz, respectively. The percentage decrease of the frequency of mEPSCs, from exposure to air to 1% sevoflurane, of the TH‑WT group (48.32%±3.08%) was significantly higher, as compared with the WT (39.17%±1.42%) and W1118 (35.10%±2.66%) groups, and there was no statistical difference between the WT and W1118 groups. The transgenic TH‑WT Drosophila presented an early decrease in locomotor ability, as compared with the WT and W1118 groups. Following a 5 hour exposure to sevoflurane, the percentage decrease of the climbing abilities of the TH‑WT group, from exposure to air to 1% sevoflurane, were significantly lower, as compared with the WT and W1118 groups. In conclusion, sevoflurane had negative effects on the control W1118 flies, and also severely aggravated the prognosis of PD in the LRRK2‑associated Drosophila model, through synaptic cholinergic deficits and impairment on locomotor abilities.
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Affiliation(s)
- Zhiming Shan
- Department of Anesthesiology, The First Affiliated Hospital of Sun Yat‑sen University, Guangzhou, Guangdong 510080, P.R. China
| | - Song Cai
- Department of Anatomy and Neurobiology, Zhongshan School of Medicine, Sun Yat‑sen University, Guangzhou, Guangdong 510080, P.R. China
| | - Tao Zhang
- Department of Anesthesiology, The First Affiliated Hospital of Sun Yat‑sen University, Guangzhou, Guangdong 510080, P.R. China
| | - Liting Kuang
- Department of Anesthesiology, The First Affiliated Hospital of Sun Yat‑sen University, Guangzhou, Guangdong 510080, P.R. China
| | - Qi Wang
- Department of Anatomy and Neurobiology, Zhongshan School of Medicine, Sun Yat‑sen University, Guangzhou, Guangdong 510080, P.R. China
| | - Huanhuan Xiu
- Department of Anesthesiology, The First Affiliated Hospital of Sun Yat‑sen University, Guangzhou, Guangdong 510080, P.R. China
| | - Jing Wen
- Department of Anesthesiology, The First Affiliated Hospital of Sun Yat‑sen University, Guangzhou, Guangdong 510080, P.R. China
| | - Huaiyu Gu
- Department of Anatomy and Neurobiology, Zhongshan School of Medicine, Sun Yat‑sen University, Guangzhou, Guangdong 510080, P.R. China
| | - Kangqing Xu
- Department of Anesthesiology, The First Affiliated Hospital of Sun Yat‑sen University, Guangzhou, Guangdong 510080, P.R. China
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26
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Chen AY, Xia S, Wilburn P, Tully T. Olfactory deficits in an alpha-synuclein fly model of Parkinson's disease. PLoS One 2014; 9:e97758. [PMID: 24879013 PMCID: PMC4039441 DOI: 10.1371/journal.pone.0097758] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2014] [Accepted: 04/23/2014] [Indexed: 12/15/2022] Open
Abstract
Parkinson’s disease (PD) is the most common motor neurodegenerative disorder. Olfactory dysfunction is a prevalent feature of PD. It often precedes motor symptoms by several years and is used in assisting PD diagnosis. However, the cellular and molecular bases of olfactory dysfunction in PD are not known. The fruit fly Drosophila melanogaster, expressing human alpha-synuclein protein or its mutant, A30P, captures several hallmarks of PD and has been successfully used to model PD in numerous studies. First, we report olfactory deficits in fly expressing A30P (A30P), showing deficits in two out of three olfactory modalities, tested – olfactory acuity and odor discrimination. The remaining third modality is odor identification/naming. Second, oxidative stress is an important environmental risk factor of PD. We show that oxidative stress exacerbated the two affected olfactory modalities in younger A30P flies. Third, different olfactory receptor neurons are activated differentially by different odors in flies. In a separate experiment, we show that the odor discrimination deficit in A30P flies is general and not restricted to a specific class of chemical structure. Lastly, by restricting A30P expression to dopamine, serotonin or olfactory receptor neurons, we show that A30P expression in dopamine neurons is necessary for development of both acuity and discrimination deficits, while serotonin and olfactory receptor neurons appeared not involved. Our data demonstrate olfactory deficits in a synuclein fly PD model for exploring olfactory pathology and physiology, and for monitoring PD progression and treatment.
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Affiliation(s)
- Alex Y. Chen
- Dart Neuroscience LLC, San Diego, California, United States of America
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
- Graduate Program in Neuroscience, SUNY Stony Brook, Stony Brook, New York, United States of America
- * E-mail:
| | - Shouzhen Xia
- Dart Neuroscience LLC, San Diego, California, United States of America
| | - Paul Wilburn
- W.K. Kellogg Biological Station, Michigan State University, Hickory Corners, Michigan, United States of America
| | - Tim Tully
- Dart Neuroscience LLC, San Diego, California, United States of America
- Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
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27
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Ono F. Big answers from a small fly with a cultured brain. J Physiol 2013; 591:3. [DOI: 10.1113/jphysiol.2012.246538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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