1
|
Yoshino J, Mali SS, Williams CR, Morita T, Emerson CE, Arp CJ, Miller SE, Yin C, Thé L, Hemmi C, Motoyoshi M, Ishii K, Emoto K, Bautista DM, Parrish JZ. Drosophila epidermal cells are intrinsically mechanosensitive and modulate nociceptive behavioral outputs. eLife 2025; 13:RP95379. [PMID: 40353351 PMCID: PMC12068870 DOI: 10.7554/elife.95379] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2025] Open
Abstract
Somatosensory neurons (SSNs) that detect and transduce mechanical, thermal, and chemical stimuli densely innervate an animal's skin. However, although epidermal cells provide the first point of contact for sensory stimuli, our understanding of roles that epidermal cells play in SSN function, particularly nociception, remains limited. Here, we show that stimulating Drosophila epidermal cells elicits activation of SSNs including nociceptors and triggers a variety of behavior outputs, including avoidance and escape. Further, we find that epidermal cells are intrinsically mechanosensitive and that epidermal mechanically evoked calcium responses require the store-operated calcium channel Orai. Epidermal cell stimulation augments larval responses to acute nociceptive stimuli and promotes prolonged hypersensitivity to subsequent mechanical stimuli. Hence, epidermal cells are key determinants of nociceptive sensitivity and sensitization, acting as primary sensors of noxious stimuli that tune nociceptor output and drive protective behaviors.
Collapse
Affiliation(s)
- Jiro Yoshino
- Department of Biology, University of WashingtonSeattleUnited States
- Department of Biological Sciences, Graduate School of Science, The University of TokyoTokyoJapan
- Division of Education, Marine Biological LaboratoryWoods HoleUnited States
| | - Sonali S Mali
- Division of Education, Marine Biological LaboratoryWoods HoleUnited States
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
- Helen Wills Neuroscience Institute, University of California, BerkeleyBerkeleyUnited States
| | - Claire R Williams
- Department of Biology, University of WashingtonSeattleUnited States
- Division of Education, Marine Biological LaboratoryWoods HoleUnited States
| | - Takeshi Morita
- Division of Education, Marine Biological LaboratoryWoods HoleUnited States
- Laboratory of Neurogenetics and Behavior, The Rockefeller UniversityNew YorkUnited States
| | - Chloe E Emerson
- Division of Education, Marine Biological LaboratoryWoods HoleUnited States
| | - Christopher J Arp
- Division of Education, Marine Biological LaboratoryWoods HoleUnited States
| | - Sophie E Miller
- Division of Education, Marine Biological LaboratoryWoods HoleUnited States
| | - Chang Yin
- Department of Biology, University of WashingtonSeattleUnited States
| | - Lydia Thé
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
| | - Chikayo Hemmi
- Department of Biological Sciences, Graduate School of Science, The University of TokyoTokyoJapan
| | - Mana Motoyoshi
- Department of Biological Sciences, Graduate School of Science, The University of TokyoTokyoJapan
| | - Kenichi Ishii
- Department of Biological Sciences, Graduate School of Science, The University of TokyoTokyoJapan
| | - Kazuo Emoto
- Department of Biological Sciences, Graduate School of Science, The University of TokyoTokyoJapan
- International Research Center for Neurointelligence (WPI-IRCN), The University of TokyoTokyoJapan
| | - Diana M Bautista
- Division of Education, Marine Biological LaboratoryWoods HoleUnited States
- Department of Molecular and Cell Biology, University of California, BerkeleyBerkeleyUnited States
- Helen Wills Neuroscience Institute, University of California, BerkeleyBerkeleyUnited States
- Howard Hughes Medical Institute, University of California at BerkeleyBerkeleyUnited States
| | - Jay Z Parrish
- Department of Biology, University of WashingtonSeattleUnited States
- Division of Education, Marine Biological LaboratoryWoods HoleUnited States
| |
Collapse
|
2
|
Mauthner SE, Tracey WD. Optogenetic Stimulation of Nociceptive Escape Behaviors in Drosophila Larvae. Cold Spring Harb Protoc 2025; 2025:pdb.prot108128. [PMID: 39095077 PMCID: PMC11787400 DOI: 10.1101/pdb.prot108128] [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] [Indexed: 08/04/2024]
Abstract
In animals, noxious stimuli activate a neural process called nociception. Drosophila larvae perform a rolling escape locomotion behavior in response to nociceptive sensory stimuli. Noxious mechanical, thermal, and chemical stimuli each trigger this same escape response in larvae. The polymodal sensory neurons that initiate the rolling response have been identified based on the expression patterns of genes that are known to be required for nociception responses. The synaptic output of these neurons, known as class IV multidendritic sensory neurons, is required for behavioral responses to thermal, mechanical, and chemical triggers of the rolling escape locomotion. Importantly, optogenetic stimulation of the class IV multidendritic neurons has also shown that the activation of those cells is sufficient to trigger nociceptive rolling. Optogenetics uses light-activated ion channels expressed in neurons of interest to bypass the normal physiological transduction machinery so that the cell may be activated in response to light that is applied by the investigator. This protocol describes an optogenetic technique that uses channelrhodopsin-2 (ChR2) to activate larval nociceptors and trigger nociceptive rolling. First, we explain how to set up the necessary genetic crosses and culture the larval progeny. Next, we describe how to perform the optogenetic nociception assay on third-instar larvae.
Collapse
Affiliation(s)
- Stephanie E Mauthner
- Gill Center for Biomolecular Science, Indiana University, Bloomington, Indiana 47405, USA
- Department of Biology, Indiana University, Bloomington, Indiana 47405, USA
| | - W Daniel Tracey
- Gill Center for Biomolecular Science, Indiana University, Bloomington, Indiana 47405, USA
- Department of Biology, Indiana University, Bloomington, Indiana 47405, USA
| |
Collapse
|
3
|
Mauthner SE, Tracey WD. Mechanical Nociception Assay in Drosophila Larvae. Cold Spring Harb Protoc 2025; 2025:pdb.prot108125. [PMID: 39095079 PMCID: PMC11787401 DOI: 10.1101/pdb.prot108125] [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] [Indexed: 08/04/2024]
Abstract
The nervous system of animals can sense and respond to noxious stimuli, which include noxious thermal, chemical, or mechanical stimuli, through a process called nociception. Here, we describe a simple behavioral assay to measure mechanically induced nociceptive responses in Drosophila larvae. This assay tests larval mechanosensitivity to noxious force with calibrated von Frey filaments. First, we explain how to construct and calibrate the customizable von Frey filaments that can be used to deliver reproducible stimuli of a defined force or pressure. Next, we describe how to perform the mechanical nociception assay on third-instar larvae. Through comparison of the responses of genotypes of interest, this assay can be useful for investigation of molecular, cellular, and circuit mechanisms of mechanical nociception. At the molecular level, prior studies have identified the importance of sensory ion channels such as Pickpocket/Balboa, Piezo, dTRPA1, and Painless. At the cellular level, the class IV multidendritic arborizing (md-da) neurons are the main mechanical nociceptor neurons of the peripheral system, but class III and class II md-da have been found to also play a role. At the circuit level, studies have shown that mechanical nociception relies on interneurons of the abdominal ganglia that integrate inputs from these various md-da neuron classes.
Collapse
Affiliation(s)
- Stephanie E Mauthner
- Gill Center for Biomolecular Science, Indiana University, Bloomington, Indiana 47405, USA
- Department of Biology, Indiana University, Bloomington, Indiana 47405, USA
| | - W Daniel Tracey
- Gill Center for Biomolecular Science, Indiana University, Bloomington, Indiana 47405, USA
- Department of Biology, Indiana University, Bloomington, Indiana 47405, USA
| |
Collapse
|
4
|
Borjon LJ, Mauthner SE, Tracey WD. Nociception in Drosophila Larvae. Cold Spring Harb Protoc 2025; 2025:pdb.top108172. [PMID: 39095078 PMCID: PMC11787404 DOI: 10.1101/pdb.top108172] [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] [Indexed: 08/04/2024]
Abstract
Nociception is the sensory modality by which animals sense stimuli associated with injury or potential tissue damage. When Drosophila larvae encounter a noxious thermal, chemical, or mechanical stimulus, they perform a stereotyped rolling behavior. These noxious stimuli are detected by polymodal nociceptor neurons that tile the larval epidermis. Although several types of sensory neurons feed into the nociceptive behavioral output, the highly branched class IV multidendritic arborization neurons are the most critical. At the molecular level, Drosophila nociception shares many conserved features with vertebrate nociception, making it a useful organism for medically relevant research in this area. Here, we review three larval assays for nociceptive behavior using mechanical stimuli, optogenetic activation, and the naturalistic stimuli of parasitoid wasp attacks. Together, the assays described have been successfully used by many laboratories in studies of the molecular, cellular, and circuit mechanisms of nociception. In addition, the simple nature of the assays we describe can be useful in teaching laboratories for undergraduate students.
Collapse
Affiliation(s)
- Lydia J Borjon
- Department of Biology, Indiana University, Bloomington, Indiana 47405, USA
- Gill Center for Biomolecular Sciences, Bloomington, Indiana 47405, USA
| | - Stephanie E Mauthner
- Department of Biology, Indiana University, Bloomington, Indiana 47405, USA
- Gill Center for Biomolecular Sciences, Bloomington, Indiana 47405, USA
| | - W Daniel Tracey
- Department of Biology, Indiana University, Bloomington, Indiana 47405, USA
- Gill Center for Biomolecular Sciences, Bloomington, Indiana 47405, USA
| |
Collapse
|
5
|
Borjon LJ, de Assis Ferreira LC, Trinidad JC, Šašić S, Hohmann AG, Tracey WD. Multiple mechanisms of action for an extremely painful venom. Curr Biol 2025; 35:444-453.e4. [PMID: 39765227 PMCID: PMC12080746 DOI: 10.1016/j.cub.2024.11.070] [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: 08/30/2024] [Revised: 11/14/2024] [Accepted: 11/28/2024] [Indexed: 01/15/2025]
Abstract
Evolutionary arms races can lead to extremely specific and effective defense mechanisms, including venoms that deter predators by targeting nociceptive (pain-sensing) pathways. The venom of velvet ants (Hymenoptera: Mutillidae) is notoriously painful. It has been described as "Explosive and long lasting, you sound insane as you scream. Hot oil from the deep fryer spilling over your entire hand."1 The effectiveness of the velvet ant sting against potential predators has been shown across vertebrate orders, including mammals, amphibians, reptiles, and birds.2,3,4 This leads to the hypothesis that velvet ant venom targets a conserved nociception mechanism, which we sought to uncover using Drosophila melanogaster as a model system. Drosophila larvae have peripheral sensory neurons that sense potentially damaging (noxious) stimuli such as high temperature, harsh mechanical touch, and noxious chemicals.5,6,7,8 They share features with vertebrate nociceptors, including conserved sensory receptor channels.9,10 We found that velvet ant venom strongly activated Drosophila nociceptors through heteromeric Pickpocket/Balboa (Ppk/Bba) ion channels, through a single venom peptide, Do6a. Drosophila Ppk/Bba is homologous to mammalian acid-sensing ion channels (ASICs).11 However, Do6a did not produce behavioral signs of nociception in mice, which was instead triggered by other venom peptides that are non-specific and less potent on Drosophila nociceptors. This suggests that Do6a has an insect-specific function. In fact, we further demonstrated that the velvet ant's sting produced aversive behavior in a predatory praying mantis. Together, our results indicate that velvet ant venom acts through different molecular mechanisms in vertebrates and invertebrates.
Collapse
Affiliation(s)
- Lydia J Borjon
- Department of Biology, Indiana University, Bloomington, IN 47405, USA; Gill Institute for Neuroscience, Indiana University, Bloomington, IN 47405, USA
| | - Luana C de Assis Ferreira
- Gill Institute for Neuroscience, Indiana University, Bloomington, IN 47405, USA; Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN 47405, USA
| | | | - Sunčica Šašić
- Department of Biology, Indiana University, Bloomington, IN 47405, USA; Gill Institute for Neuroscience, Indiana University, Bloomington, IN 47405, USA
| | - Andrea G Hohmann
- Gill Institute for Neuroscience, Indiana University, Bloomington, IN 47405, USA; Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN 47405, USA; Program in Neuroscience, Indiana University, Bloomington, IN 47405, USA
| | - W Daniel Tracey
- Department of Biology, Indiana University, Bloomington, IN 47405, USA; Gill Institute for Neuroscience, Indiana University, Bloomington, IN 47405, USA; Program in Neuroscience, Indiana University, Bloomington, IN 47405, USA.
| |
Collapse
|
6
|
Yuan Y, Yu L, Zhuang X, Wen D, He J, Hong J, Xie J, Ling S, Du X, Chen W, Wang X. Drosophila models used to simulate human ATP1A1 gene mutations that cause Charcot-Marie-Tooth type 2 disease and refractory seizures. Neural Regen Res 2025; 20:265-276. [PMID: 38767491 PMCID: PMC11246156 DOI: 10.4103/1673-5374.391302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 09/21/2023] [Accepted: 11/06/2023] [Indexed: 05/22/2024] Open
Abstract
JOURNAL/nrgr/04.03/01300535-202501000-00034/figure1/v/2024-05-14T021156Z/r/image-tiff Certain amino acids changes in the human Na+/K+-ATPase pump, ATPase Na+/K+ transporting subunit alpha 1 (ATP1A1), cause Charcot-Marie-Tooth disease type 2 (CMT2) disease and refractory seizures. To develop in vivo models to study the role of Na+/K+-ATPase in these diseases, we modified the Drosophila gene homolog, Atpα, to mimic the human ATP1A1 gene mutations that cause CMT2. Mutations located within the helical linker region of human ATP1A1 (I592T, A597T, P600T, and D601F) were simultaneously introduced into endogenous DrosophilaAtpα by CRISPR/Cas9-mediated genome editing, generating the AtpαTTTF model. In addition, the same strategy was used to generate the corresponding single point mutations in flies (AtpαI571T, AtpαA576T, AtpαP579T, and AtpαD580F). Moreover, a deletion mutation (Atpαmut) that causes premature termination of translation was generated as a positive control. Of these alleles, we found two that could be maintained as homozygotes (AtpαI571T and AtpαP579T). Three alleles (AtpαA576T, AtpαP579 and AtpαD580F) can form heterozygotes with the Atpαmut allele. We found that the Atpα allele carrying these CMT2-associated mutations showed differential phenotypes in Drosophila. Flies heterozygous for AtpαTTTF mutations have motor performance defects, a reduced lifespan, seizures, and an abnormal neuronal morphology. These Drosophila models will provide a new platform for studying the function and regulation of the sodium-potassium pump.
Collapse
Affiliation(s)
- Yao Yuan
- Institute of Life Sciences, College of Biological Science and Engineering, Fuzhou University, Fuzhou, Fujian Province, China
| | - Lingqi Yu
- Institute of Life Sciences, College of Biological Science and Engineering, Fuzhou University, Fuzhou, Fujian Province, China
| | - Xudong Zhuang
- NHC Key Laboratory of Technical Evaluation of Fertility Regulation for Non-human Primate (Fujian Maternity and Child Health Hospital), Fuzhou, Fujian Province, China
- Medical Research Center, Fujian Maternity and Child Health Hospital, College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fuzhou, Fujian Province, China
| | - Dongjing Wen
- Institute of Life Sciences, College of Biological Science and Engineering, Fuzhou University, Fuzhou, Fujian Province, China
| | - Jin He
- Department of Neurology and Institute of Neurology of The First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, Fujian Province, China
| | - Jingmei Hong
- Department of Neurology and Institute of Neurology of The First Affiliated Hospital, Institute of Neuroscience, and Fujian Key Laboratory of Molecular Neurology, Fujian Medical University, Fuzhou, Fujian Province, China
| | - Jiayu Xie
- Institute of Life Sciences, College of Biological Science and Engineering, Fuzhou University, Fuzhou, Fujian Province, China
| | - Shengan Ling
- Institute of Life Sciences, College of Biological Science and Engineering, Fuzhou University, Fuzhou, Fujian Province, China
| | - Xiaoyue Du
- Institute of Life Sciences, College of Biological Science and Engineering, Fuzhou University, Fuzhou, Fujian Province, China
| | - Wenfeng Chen
- Institute of Life Sciences, College of Biological Science and Engineering, Fuzhou University, Fuzhou, Fujian Province, China
| | - Xinrui Wang
- NHC Key Laboratory of Technical Evaluation of Fertility Regulation for Non-human Primate (Fujian Maternity and Child Health Hospital), Fuzhou, Fujian Province, China
- Medical Research Center, Fujian Maternity and Child Health Hospital, College of Clinical Medicine for Obstetrics & Gynecology and Pediatrics, Fujian Medical University, Fuzhou, Fujian Province, China
| |
Collapse
|
7
|
Tann JY, Xu F, Kimura M, Wilkes OR, Yoong LF, Skibbe H, Moore AW. Study of Dendrite Differentiation Using Drosophila Dendritic Arborization Neurons. Cold Spring Harb Protoc 2024; 2024:pdb.top108146. [PMID: 38148165 DOI: 10.1101/pdb.top108146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2023]
Abstract
Neurons receive, process, and integrate inputs. These operations are organized by dendrite arbor morphology, and the dendritic arborization (da) neurons of the Drosophila peripheral sensory nervous system are an excellent experimental model for examining the differentiation processes that build and shape the dendrite arbor. Studies in da neurons are enabled by a wealth of fly genetic tools that allow targeted neuron manipulation and labeling of the neuron's cytoskeletal or organellar components. Moreover, as da neuron dendrite arbors cover the body wall, they are highly accessible for live imaging analysis of arbor patterning. Here, we outline the structure and function of different da neuron types and give examples of how they are used to elucidate central mechanisms of dendritic arbor formation.
Collapse
Affiliation(s)
- Jason Y Tann
- Laboratory for Neurodiversity, RIKEN Center for Brain Science, Wako-shi, 351-0106, Japan
| | - Fangke Xu
- Laboratory for Neurodiversity, RIKEN Center for Brain Science, Wako-shi, 351-0106, Japan
| | - Minami Kimura
- Laboratory for Neurodiversity, RIKEN Center for Brain Science, Wako-shi, 351-0106, Japan
| | - Oliver R Wilkes
- Laboratory for Neurodiversity, RIKEN Center for Brain Science, Wako-shi, 351-0106, Japan
- Department of Cellular and Molecular Biology, Institute for Translational Medicine, University of Liverpool, Liverpool L69 3BX, United Kingdom
| | - Li-Foong Yoong
- Laboratory for Neurodiversity, RIKEN Center for Brain Science, Wako-shi, 351-0106, Japan
| | - Henrik Skibbe
- Brain Image Analysis Unit, RIKEN Center for Brain Science, Wako-shi, 351-0106, Japan
| | - Adrian W Moore
- Laboratory for Neurodiversity, RIKEN Center for Brain Science, Wako-shi, 351-0106, Japan
| |
Collapse
|
8
|
Borjon LJ, de Assis Ferreira LC, Trinidad JC, Šašić S, Hohmann AG, Tracey WD. Multiple mechanisms of action of an extremely painful venom. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.09.12.612741. [PMID: 39314321 PMCID: PMC11419154 DOI: 10.1101/2024.09.12.612741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 09/25/2024]
Abstract
Evolutionary arms races between predator and prey can lead to extremely specific and effective defense mechanisms. Such defenses include venoms that deter predators by targeting nociceptive (pain-sensing) pathways. Through co-evolution, venom toxins can become extremely efficient modulators of their molecular targets. The venom of velvet ants (Hymenoptera: Mutillidae) is notoriously painful. The intensity of a velvet ant sting has been described as "Explosive and long lasting, you sound insane as you scream. Hot oil from the deep fryer spilling over your entire hand." [1] The effectiveness of the velvet ant sting as a deterrent against potential predators has been shown across vertebrate orders, including mammals, amphibians, reptiles, and birds [2-4]. The venom's low toxicity suggests it has a targeted effect on nociceptive sensory mechanisms [5]. This leads to the hypothesis that velvet ant venom targets a conserved nociception mechanism, which we sought to uncover using Drosophila melanogaster as a model system. Drosophila larvae have peripheral sensory neurons that sense potentially damaging (noxious) stimuli such as high temperature, harsh mechanical touch, and noxious chemicals [6-9]. These polymodal nociceptors are called class IV multidendritic dendritic arborizing (cIV da) neurons, and they share many features with vertebrate nociceptors, including conserved sensory receptor channels [10,11]. We found that velvet ant venom strongly activated Drosophila nociceptors through heteromeric Pickpocket/Balboa (Ppk/Bba) ion channels. Furthermore, we found a single venom peptide (Do6a) that activated larval nociceptors at nanomolar concentrations through Ppk/Bba. Drosophila Ppk/Bba is homologous to mammalian Acid Sensing Ion Channels (ASICs) [12]. However, the Do6a peptide did not produce behavioral signs of nociception in mice, which was instead triggered by other non-specific, less potent, peptides within the venom. This suggests that Do6a is an insect-specific venom component that potently activates insect nociceptors. Consistent with this, we showed that the velvet ant's defensive sting produced aversive behavior in a predatory praying mantis. Together, our results indicate that velvet ant venom evolved to target nociceptive systems of both vertebrates and invertebrates, but through different molecular mechanisms.
Collapse
Affiliation(s)
- Lydia J. Borjon
- Department of Biology, Indiana University; Bloomington, IN
- Gill Institute for Neuroscience, Indiana University; Bloomington, IN
| | - Luana C. de Assis Ferreira
- Gill Institute for Neuroscience, Indiana University; Bloomington, IN
- Department of Psychological and Brain Sciences, Indiana University; Bloomington, IN
| | | | - Sunčica Šašić
- Department of Biology, Indiana University; Bloomington, IN
- Gill Institute for Neuroscience, Indiana University; Bloomington, IN
| | - Andrea G. Hohmann
- Gill Institute for Neuroscience, Indiana University; Bloomington, IN
- Department of Psychological and Brain Sciences, Indiana University; Bloomington, IN
- Program in Neuroscience, Indiana University; Bloomington, IN
| | - W. Daniel Tracey
- Department of Biology, Indiana University; Bloomington, IN
- Gill Institute for Neuroscience, Indiana University; Bloomington, IN
- Program in Neuroscience, Indiana University; Bloomington, IN
| |
Collapse
|
9
|
Kim JY, Yang JE, Mitchell JW, English LA, Yang SZ, Tenpas T, Dent EW, Wildonger J, Wright ER. Handling Difficult Cryo-ET Samples: A Study with Primary Neurons from Drosophila melanogaster. MICROSCOPY AND MICROANALYSIS : THE OFFICIAL JOURNAL OF MICROSCOPY SOCIETY OF AMERICA, MICROBEAM ANALYSIS SOCIETY, MICROSCOPICAL SOCIETY OF CANADA 2023; 29:2127-2148. [PMID: 37966978 PMCID: PMC11168236 DOI: 10.1093/micmic/ozad125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Revised: 10/01/2023] [Accepted: 10/18/2023] [Indexed: 11/17/2023]
Abstract
Cellular neurobiology has benefited from recent advances in the field of cryo-electron tomography (cryo-ET). Numerous structural and ultrastructural insights have been obtained from plunge-frozen primary neurons cultured on electron microscopy grids. With most primary neurons having been derived from rodent sources, we sought to expand the breadth of sample availability by using primary neurons derived from 3rd instar Drosophila melanogaster larval brains. Ultrastructural abnormalities were encountered while establishing this model system for cryo-ET, which were exemplified by excessive membrane blebbing and cellular fragmentation. To optimize neuronal samples, we integrated substrate selection, micropatterning, montage data collection, and chemical fixation. Efforts to address difficulties in establishing Drosophila neurons for future cryo-ET studies in cellular neurobiology also provided insights that future practitioners can use when attempting to establish other cell-based model systems.
Collapse
Affiliation(s)
- Joseph Y. Kim
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Jie E. Yang
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
- Cryo-Electron Microscopy Research Center, University of Wisconsin-Madison, Madison, WI 53706, USA
- Midwest Center for Cryo-Electron Tomography, Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Josephine W. Mitchell
- Department of Chemistry and Biochemistry, Kalamazoo College, Kalamazoo, MI 49006, USA
| | - Lauren A. English
- Neuroscience Training Program, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Sihui Z. Yang
- Department of Biology, Stanford University, Stanford, CA 94305, USA
| | - Tanner Tenpas
- Department of Neuroscience, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Erik W. Dent
- Department of Neuroscience, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Jill Wildonger
- Departments of Pediatrics and Biological Sciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Elizabeth R. Wright
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
- Cryo-Electron Microscopy Research Center, University of Wisconsin-Madison, Madison, WI 53706, USA
- Midwest Center for Cryo-Electron Tomography, Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
- Morgridge Institute for Research, University of Wisconsin-Madison, Madison, WI 53715, USA
| |
Collapse
|
10
|
Mitchell JW, Midillioglu I, Schauer E, Wang B, Han C, Wildonger J. Coordination of Pickpocket ion channel delivery and dendrite growth in Drosophila sensory neurons. PLoS Genet 2023; 19:e1011025. [PMID: 37943859 PMCID: PMC10662761 DOI: 10.1371/journal.pgen.1011025] [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: 07/31/2023] [Revised: 11/21/2023] [Accepted: 10/23/2023] [Indexed: 11/12/2023] Open
Abstract
Sensory neurons enable an organism to perceive external stimuli, which is essential for survival. The sensory capacity of a neuron depends on the elaboration of its dendritic arbor and the localization of sensory ion channels to the dendritic membrane. However, it is not well understood when and how ion channels localize to growing sensory dendrites and whether their delivery is coordinated with growth of the dendritic arbor. We investigated the localization of the DEG/ENaC/ASIC ion channel Pickpocket (Ppk) in the peripheral sensory neurons of developing fruit flies. We used CRISPR-Cas9 genome engineering approaches to tag endogenous Ppk1 and visualize it live, including monitoring Ppk1 membrane localization via a novel secreted split-GFP approach. Fluorescently tagged endogenous Ppk1 localizes to dendrites, as previously reported, and, unexpectedly, to axons and axon terminals. In dendrites, Ppk1 is present throughout actively growing dendrite branches and is stably integrated into the neuronal cell membrane during the expansive growth of the arbor. Although Ppk channels are dispensable for dendrite growth, we found that an over-active channel mutant severely reduces dendrite growth, likely by acting at an internal membrane and not the dendritic membrane. Our data reveal that the molecular motor dynein and recycling endosome GTPase Rab11 are needed for the proper trafficking of Ppk1 to dendrites. Based on our data, we propose that Ppk channel transport is coordinated with dendrite morphogenesis, which ensures proper ion channel density and distribution in sensory dendrites.
Collapse
Affiliation(s)
- Josephine W. Mitchell
- Integrated Program in Biochemistry, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Biochemistry Department, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Department of Chemistry and Biochemistry, Kalamazoo College, Kalamazoo, Michigan, United States of America
| | - Ipek Midillioglu
- Pediatrics, University of California, San Diego, La Jolla, California, United States of America
| | - Ethan Schauer
- Pediatrics, University of California, San Diego, La Jolla, California, United States of America
| | - Bei Wang
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York, United States of America
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York, United States of America
| | - Chun Han
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, New York, United States of America
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York, United States of America
| | - Jill Wildonger
- Biochemistry Department, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Pediatrics, University of California, San Diego, La Jolla, California, United States of America
- Cell & Developmental Biology, School of Biological Sciences, University of California, San Diego, La Jolla, California, United States of America
| |
Collapse
|
11
|
Kim JY, Yang JE, Mitchell JW, English LA, Yang SZ, Tenpas T, Dent EW, Wildonger J, Wright ER. Handling difficult cryo-ET samples: A study with primary neurons from Drosophila melanogaster. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.10.548468. [PMID: 37502991 PMCID: PMC10369871 DOI: 10.1101/2023.07.10.548468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
Cellular neurobiology has benefited from recent advances in the field of cryo-electron tomography (cryo-ET). Numerous structural and ultrastructural insights have been obtained from plunge-frozen primary neurons cultured on electron microscopy grids. With most primary neurons been derived from rodent sources, we sought to expand the breadth of sample availability by using primary neurons derived from 3rd instar Drosophila melanogaster larval brains. Ultrastructural abnormalities were encountered while establishing this model system for cryo-ET, which were exemplified by excessive membrane blebbing and cellular fragmentation. To optimize neuronal samples, we integrated substrate selection, micropatterning, montage data collection, and chemical fixation. Efforts to address difficulties in establishing Drosophila neurons for future cryo-ET studies in cellular neurobiology also provided insights that future practitioners can use when attempting to establish other cell-based model systems.
Collapse
Affiliation(s)
- Joseph Y. Kim
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Jie E. Yang
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
- Cryo-Electron Microscopy Research Center, University of Wisconsin-Madison, Madison, WI, 53706, USA
- Midwest Center for Cryo-Electron Tomography, Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Josephine W. Mitchell
- Department of Chemistry and Biochemistry, Kalamazoo College, Kalamazoo, MI, 49006, USA
| | - Lauren A. English
- Neuroscience Training Program, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - Sihui Z. Yang
- Department of Biology, Stanford University, Stanford, CA, 94305, USA
| | - Tanner Tenpas
- Department of Neuroscience, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - Erik W. Dent
- Department of Neuroscience, University of Wisconsin-Madison, Madison, WI, 53705, USA
| | - Jill Wildonger
- Departments of Pediatrics and Biological Sciences, University of California, San Diego, La Jolla, CA, 92093, USA
| | - Elizabeth R. Wright
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
- Cryo-Electron Microscopy Research Center, University of Wisconsin-Madison, Madison, WI, 53706, USA
- Midwest Center for Cryo-Electron Tomography, Department of Biochemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
- Morgridge Institute for Research, University of Wisconsin-Madison, Madison, WI, 53715, USA
| |
Collapse
|
12
|
Wang Y, Lopez-Bellido R, Huo X, Kavelaars A, Galko MJ. The insulin receptor regulates the persistence of mechanical nociceptive sensitization in flies and mice. Biol Open 2023; 12:bio059864. [PMID: 37259940 PMCID: PMC10245137 DOI: 10.1242/bio.059864] [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: 02/08/2023] [Accepted: 04/28/2023] [Indexed: 05/10/2023] Open
Abstract
Early phase diabetes is often accompanied by pain sensitization. In Drosophila, the insulin receptor (InR) regulates the persistence of injury-induced thermal nociceptive sensitization. Whether Drosophila InR also regulates the persistence of mechanical nociceptive sensitization remains unclear. Mice with a sensory neuron deletion of the insulin receptor (Insr) show normal nociceptive baselines; however, it is uncertain whether deletion of Insr in nociceptive sensory neurons leads to persistent nociceptive hypersensitivity. In this study, we used fly and mouse nociceptive sensitization models to address these questions. In flies, InR mutants and larvae with sensory neuron-specific expression of RNAi transgenes targeting InR exhibited persistent mechanical hypersensitivity. Mice with a specific deletion of the Insr gene in Nav1.8+ nociceptive sensory neurons showed nociceptive thermal and mechanical baselines similar to controls. In an inflammatory paradigm, however, these mutant mice showed persistent mechanical (but not thermal) hypersensitivity, particularly in female mice. Mice with the Nav1.8+ sensory neuron-specific deletion of Insr did not show metabolic abnormalities typical of a defect in systemic insulin signaling. Our results show that some aspects of the regulation of nociceptive hypersensitivity by the insulin receptor are shared between flies and mice and that this regulation is likely independent of metabolic effects.
Collapse
Affiliation(s)
- Yan Wang
- Department of Genetics, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Roger Lopez-Bellido
- Department of Genetics, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Xiaojiao Huo
- Department of Symptom Research, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Annemieke Kavelaars
- Department of Symptom Research, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- Neuroscience Graduate Program, The MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX 77030, USA
| | - Michael J. Galko
- Department of Genetics, University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
- Neuroscience Graduate Program, The MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX 77030, USA
- Genetics & Epigenetics Graduate Program, The MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX 77030, USA
| |
Collapse
|
13
|
Oikawa I, Kondo S, Hashimoto K, Yoshida A, Hamajima M, Tanimoto H, Furukubo-Tokunaga K, Honjo K. A descending inhibitory mechanism of nociception mediated by an evolutionarily conserved neuropeptide system in Drosophila. eLife 2023; 12:RP85760. [PMID: 37310871 DOI: 10.7554/elife.85760] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/15/2023] Open
Abstract
Nociception is a neural process that animals have developed to avoid potentially tissue-damaging stimuli. While nociception is triggered in the peripheral nervous system, its modulation by the central nervous system is a critical process in mammals, whose dysfunction has been extensively implicated in chronic pain pathogenesis. The peripheral mechanisms of nociception are largely conserved across the animal kingdom. However, it is unclear whether the brain-mediated modulation is also conserved in non-mammalian species. Here, we show that Drosophila has a descending inhibitory mechanism of nociception from the brain, mediated by the neuropeptide Drosulfakinin (DSK), a homolog of cholecystokinin (CCK) that plays an important role in the descending control of nociception in mammals. We found that mutants lacking dsk or its receptors are hypersensitive to noxious heat. Through a combination of genetic, behavioral, histological, and Ca2+ imaging analyses, we subsequently revealed neurons involved in DSK-mediated nociceptive regulation at a single-cell resolution and identified a DSKergic descending neuronal pathway that inhibits nociception. This study provides the first evidence for a descending modulatory mechanism of nociception from the brain in a non-mammalian species that is mediated by the evolutionarily conserved CCK system, raising the possibility that the descending inhibition is an ancient mechanism to regulate nociception.
Collapse
Affiliation(s)
- Izumi Oikawa
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
| | - Shu Kondo
- Faculty of Advanced Engineering, Tokyo University of Science, Katsushika-ku, Tokyo, Japan
| | - Kao Hashimoto
- College of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
| | - Akiho Yoshida
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
| | - Megumi Hamajima
- Center for Development of Advanced Medicine for Dementia, National Center for Geriatrics and Gerontology, Obu, Japan
| | - Hiromu Tanimoto
- Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | | | - Ken Honjo
- Center for Development of Advanced Medicine for Dementia, National Center for Geriatrics and Gerontology, Obu, Japan
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
| |
Collapse
|
14
|
Goodman MB, Haswell ES, Vásquez V. Mechanosensitive membrane proteins: Usual and unusual suspects in mediating mechanotransduction. J Gen Physiol 2023; 155:e202213248. [PMID: 36696153 PMCID: PMC9930137 DOI: 10.1085/jgp.202213248] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
This Viewpoint, which accompanies a Special Issue focusing on membrane mechanosensors, discusses unifying and unique features of both established and emerging mechanosensitive (MS) membrane proteins, their distribution across protein families and phyla, and current and future challenges in the study of these important proteins and their partners. MS membrane proteins are essential for tissue development, cellular motion, osmotic homeostasis, and sensing external and self-generated mechanical cues like those responsible for touch and proprioception. Though researchers' attention and this Viewpoint focus on a few famous ion channels that are considered the usual suspects as MS mechanosensors, we also discuss some of the more unusual suspects, such as G-protein coupled receptors. As the field continues to grow, so too will the list of proteins suspected to function as mechanosensors and the diversity of known MS membrane proteins.
Collapse
Affiliation(s)
- Miriam B. Goodman
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, CA, USA
| | - Elizabeth S. Haswell
- Department of Biology, Center for Engineering Mechanobiology, Washington University in St. Louis, St. Louis, MO, USA
| | - Valeria Vásquez
- Department of Physiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| |
Collapse
|
15
|
Dyson A, Ryan M, Garg S, Evans DG, Baines RA. Loss of NF1 in Drosophila Larvae Causes Tactile Hypersensitivity and Impaired Synaptic Transmission at the Neuromuscular Junction. J Neurosci 2022; 42:9450-9472. [PMID: 36344265 PMCID: PMC9794380 DOI: 10.1523/jneurosci.0562-22.2022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2022] [Revised: 09/20/2022] [Accepted: 09/23/2022] [Indexed: 11/09/2022] Open
Abstract
Autism spectrum disorder (ASD) is a neurodevelopmental condition in which the mechanisms underlying its core symptomatology are largely unknown. Studying animal models of monogenic syndromes associated with ASD, such as neurofibromatosis type 1 (NF1), can offer insights into its etiology. Here, we show that loss of function of the Drosophila NF1 ortholog results in tactile hypersensitivity following brief mechanical stimulation in the larva (mixed sexes), paralleling the sensory abnormalities observed in individuals with ASD. Mutant larvae also exhibit synaptic transmission deficits at the glutamatergic neuromuscular junction (NMJ), with increased spontaneous but reduced evoked release. While the latter is homeostatically compensated for by a postsynaptic increase in input resistance, the former is consistent with neuronal hyperexcitability. Indeed, diminished expression of NF1 specifically within central cholinergic neurons induces both excessive neuronal firing and tactile hypersensitivity, suggesting the two may be linked. Furthermore, both impaired synaptic transmission and behavioral deficits are fully rescued via knock-down of Ras proteins. These findings validate NF1 -/- Drosophila as a tractable model of ASD with the potential to elucidate important pathophysiological mechanisms.SIGNIFICANCE STATEMENT Autism spectrum disorder (ASD) affects 1-2% of the overall population and can considerably impact an individual's quality of life. However, there are currently no treatments available for its core symptoms, largely because of a poor understanding of the underlying mechanisms involved. Examining how loss of function of the ASD-associated NF1 gene affects behavior and physiology in Drosophila may shed light on this. In this study, we identify a novel, ASD-relevant behavioral phenotype in NF1 -/- larvae, namely an enhanced response to mechanical stimulation, which is associated with Ras-dependent synaptic transmission deficits indicative of neuronal hyperexcitability. Such insights support the use of Drosophila neurofibromatosis type 1 (NF1) models in ASD research and may provide outputs for genetic or pharmacological screens in future studies.
Collapse
Affiliation(s)
- Alex Dyson
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, M13 9PT, United Kingdom
| | - Megan Ryan
- Division of Neuroscience and Experimental Psychology, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, M13 9PT, United Kingdom
| | - Shruti Garg
- Division of Neuroscience and Experimental Psychology, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, M13 9PT, United Kingdom
- Child & Adolescent Mental Health Services, Royal Manchester Children's Hospital, Central Manchester University Hospitals National Health Service Foundation Trust, Manchester Academic Health Sciences Centre, Manchester, M13 9WL, United Kingdom
| | - D Gareth Evans
- Division of Evolution, Infection and Genomics, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, M13 9PT, United Kingdom
| | - Richard A Baines
- Division of Neuroscience and Experimental Psychology, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester, M13 9PT, United Kingdom
| |
Collapse
|
16
|
Gong J, Chen J, Gu P, Shang Y, Ruppell KT, Yang Y, Wang F, Wen Q, Xiang Y. Shear stress activates nociceptors to drive Drosophila mechanical nociception. Neuron 2022; 110:3727-3742.e8. [PMID: 36087585 DOI: 10.1016/j.neuron.2022.08.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 06/07/2022] [Accepted: 08/11/2022] [Indexed: 12/15/2022]
Abstract
Mechanical nociception is essential for animal survival. However, the forces involved in nociceptor activation and the underlying mechanotransduction mechanisms remain elusive. Here, we address these problems by investigating nocifensive behavior in Drosophila larvae. We show that strong poking stimulates nociceptors with a mixture of forces including shear stress and stretch. Unexpectedly, nociceptors are selectively activated by shear stress, but not stretch. Both the shear stress responses of nociceptors and nocifensive behavior require transient receptor potential A1 (TrpA1), which is specifically expressed in nociceptors. We further demonstrate that expression of mammalian or Drosophila TrpA1 in heterologous cells confers responses to shear stress but not stretch. Finally, shear stress activates TrpA1 in a membrane-delimited manner, through modulation of membrane fluidity. Together, our study reveals TrpA1 as an evolutionarily conserved mechanosensitive channel specifically activated by shear stress and suggests a critical role of shear stress in activating nociceptors to drive mechanical nociception.
Collapse
Affiliation(s)
- Jiaxin Gong
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Jiazhang Chen
- Department of Physics, Worcester Polytechnic Institute, Worcester, MA 01605, USA
| | - Pengyu Gu
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Ye Shang
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01605, USA; Program in Neuroscience, Morningside Graduate School of Biomedical Sciences, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Kendra Takle Ruppell
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01605, USA; Program in Neuroscience, Morningside Graduate School of Biomedical Sciences, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Ying Yang
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Fei Wang
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01605, USA; Program in Neuroscience, Morningside Graduate School of Biomedical Sciences, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Qi Wen
- Department of Physics, Worcester Polytechnic Institute, Worcester, MA 01605, USA.
| | - Yang Xiang
- Department of Neurobiology, University of Massachusetts Medical School, Worcester, MA 01605, USA; Program in Neuroscience, Morningside Graduate School of Biomedical Sciences, University of Massachusetts Medical School, Worcester, MA 01605, USA.
| |
Collapse
|
17
|
Jang W, Lim JY, Kang S, Kim M, Hwang SW, Kim C. Drosophila ppk19 encodes a proton-gated and mechanosensitive ion channel. Sci Rep 2022; 12:18346. [PMID: 36319833 PMCID: PMC9626565 DOI: 10.1038/s41598-022-23236-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 10/27/2022] [Indexed: 11/05/2022] Open
Abstract
In Drosophila larvae, nociceptive mdIV sensory neurons detect diverse noxious stimuli and prompt a nociceptive rolling response. Intriguingly, the same neurons also regulate stereotyped larval movement. The channels responsible for transducing these stimuli into electric signals are not yet fully identified. Here we undertook genetic and electrophysiological analysis of Ppk19, a member of the Deg/ENaC family of cationic channels. ppk19 mutants exhibited an impaired nociceptive rolling response upon mechanical force and acid, but no impairment in response to noxious temperature and gentle touch. Mutants also exhibited defective larval movement. RNAi against ppk19 in mdIV neurons likewise produced larvae with defects in mechanical and acid nociception and larval movement, but no impairment in detection of heat and gentle touch. Cultured cells transfected with ppk19 produced currents in acid and hypotonic solution, suggesting that ppk19 encodes an ion channel that responds to acid and cell swelling. Taken together, these findings suggest that Ppk19 acts in mdIV neurons as a proton- and mechano-gated ion channel to mediate acid- and mechano-responsive nociception and larval movement.
Collapse
Affiliation(s)
- Wijeong Jang
- grid.14005.300000 0001 0356 9399School of Biological Sciences and Technology, Chonnam National University, Gwangju, 61186 Korea
| | - Ji Yeon Lim
- grid.222754.40000 0001 0840 2678Department of Biomedical Sciences and Department of Physiology, Korea University College of Medicine, Seoul, 02841 Korea
| | - Seyoung Kang
- grid.14005.300000 0001 0356 9399School of Biological Sciences and Technology, Chonnam National University, Gwangju, 61186 Korea
| | - Minseok Kim
- grid.222754.40000 0001 0840 2678Department of Biomedical Sciences and Department of Physiology, Korea University College of Medicine, Seoul, 02841 Korea
| | - Sun Wook Hwang
- grid.222754.40000 0001 0840 2678Department of Biomedical Sciences and Department of Physiology, Korea University College of Medicine, Seoul, 02841 Korea
| | - Changsoo Kim
- grid.14005.300000 0001 0356 9399School of Biological Sciences and Technology, Chonnam National University, Gwangju, 61186 Korea
| |
Collapse
|
18
|
Kaulich E, Grundy LJ, Schafer WR, Walker DS. The diverse functions of the DEG/ENaC family: linking genetic and physiological insights. J Physiol 2022; 601:1521-1542. [PMID: 36314992 PMCID: PMC10148893 DOI: 10.1113/jp283335] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Accepted: 10/25/2022] [Indexed: 11/06/2022] Open
Abstract
The DEG/ENaC family of ion channels was defined based on the sequence similarity between degenerins (DEG) from the nematode Caenorhabditis elegans and subunits of the mammalian epithelial sodium channel (ENaC), and also includes a diverse array of non-voltage-gated cation channels from across animal phyla, including the mammalian acid-sensing ion channels (ASICs) and Drosophila pickpockets. ENaCs and ASICs have wide ranging medical importance; for example, ENaCs play an important role in respiratory and renal function, and ASICs in ischaemia and inflammatory pain, as well as being implicated in memory and learning. Electrophysiological approaches, both in vitro and in vivo, have played an essential role in establishing the physiological properties of this diverse family, identifying an array of modulators and implicating them in an extensive range of cellular functions, including mechanosensation, acid sensation and synaptic modulation. Likewise, genetic studies in both invertebrates and vertebrates have played an important role in linking our understanding of channel properties to function at the cellular and whole animal/behavioural level. Drawing together genetic and physiological evidence is essential to furthering our understanding of the precise cellular roles of DEG/ENaC channels, with the diversity among family members allowing comparative physiological studies to dissect the molecular basis of these diverse functions.
Collapse
Affiliation(s)
- Eva Kaulich
- Neurobiology Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge, UK
| | - Laura J Grundy
- Neurobiology Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge, UK
| | - William R Schafer
- Neurobiology Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge, UK.,Department of Biology, KU Leuven, Leuven, Belgium
| | - Denise S Walker
- Neurobiology Division, MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge, UK
| |
Collapse
|
19
|
Satterfield LK, De J, Wu M, Qiu T, Joiner WJ. Inputs to the Sleep Homeostat Originate Outside the Brain. J Neurosci 2022; 42:5695-5704. [PMID: 35680412 PMCID: PMC9302467 DOI: 10.1523/jneurosci.2113-21.2022] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 05/27/2022] [Accepted: 05/31/2022] [Indexed: 01/22/2023] Open
Abstract
The need to sleep is sensed and discharged in a poorly understood process that is homeostatically controlled over time. In flies, different contributions to this process have been attributed to peripheral ppk and central brain neurons, with the former serving as hypothetical inputs to the sleep homeostat and the latter reportedly serving as the homeostat itself. Here we re-evaluate these distinctions in light of new findings using female flies. First, activating neurons targeted by published ppk and brain drivers elicits similar phenotypes, namely, sleep deprivation followed by rebound sleep. Second, inhibiting activity or synaptic output with one type of driver suppresses sleep homeostasis induced using the other type of driver. Third, drivers previously used to implicate central neurons in sleep homeostasis unexpectedly also label ppk neurons. Fourth, activating only this subset of colabeled neurons is sufficient to elicit sleep homeostasis. Thus, many published contributions of central neurons to sleep homeostasis can be explained by previously unrecognized expression of brain drivers in peripheral ppk neurons, most likely those in the legs, which promote walking. Last, we show that activation of certain non-ppk neurons can also induce sleep homeostasis. Notably, axons of these as well as ppk neurons terminate in the same ventral brain region, suggesting that a previously undefined neural circuit element of a sleep homeostat may lie nearby.SIGNIFICANCE STATEMENT The biological needs that sleep fulfills are unknown, but they are reflected by the ability of an animal to compensate for prior sleep loss in a process called sleep homeostasis. Researchers have searched for the neural circuitry that comprises the sleep homeostat so that the information it conveys can shed light on the nature of sleep need. Here we demonstrate that neurons originating outside of the brain are responsible for phenotypes previously attributed to the proposed central brain sleep homeostat in flies. Our results support a revised neural circuit model for sensing and discharging sleep need in which peripheral inputs connect to a sleep homeostat through previously unrecognized neural circuit elements in the ventral brain.
Collapse
Affiliation(s)
- Lawrence K Satterfield
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093
- Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, California 92093
| | - Joydeep De
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093
| | - Meilin Wu
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093
| | - Tianhao Qiu
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093
| | - William J Joiner
- Department of Pharmacology, University of California, San Diego, La Jolla, California 92093
- Biomedical Sciences Graduate Program, University of California, San Diego, La Jolla, California 92093
- Center for Circadian Biology, University of California, San Diego, La Jolla, California 92093
| |
Collapse
|
20
|
Deshpande SA, Rohrbach EW, Asuncion JD, Harrigan J, Eamani A, Schlingmann EH, Suto DJ, Lee PT, Schweizer FE, Bellen HJ, Krantz DE. Regulation of Drosophila oviduct muscle contractility by octopamine. iScience 2022; 25:104697. [PMID: 35880044 PMCID: PMC9307614 DOI: 10.1016/j.isci.2022.104697] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 04/21/2022] [Accepted: 06/27/2022] [Indexed: 11/20/2022] Open
Abstract
Octopamine is essential for egg-laying in Drosophila melanogaster, but the neuronal pathways and receptors by which it regulates visceral muscles in the reproductive tract are not known. We find that the two octopamine receptors that have been previously implicated in egg-laying–OAMB and Octβ2R-are expressed in octopaminergic and glutamatergic neurons that project to the reproductive tract, peripheral ppk(+) neurons within the reproductive tract and epithelial cells that line the lumen of the oviducts. Further optogenetic and mutational analyses indicate that octopamine regulates both oviduct contraction and relaxation via Octβ2 and OAMB respectively. Interactions with glutamatergic pathways modify the effects of octopamine. Octopaminergic activation of Octβ2R on glutamatergic processes provides a possible mechanism by which octopamine initiates lateral oviduct contractions. We speculate that aminergic pathways in the oviposition circuit may be comparable to some of the mechanisms that regulate visceral muscle contractility in mammals. The receptors Octβ2 and OAMB mediate oviduct muscle contraction and relaxation The receptors are detectably expressed in neurons and epithelia but not muscle cells The control of visceral muscles in flies and mammals may share common features
Collapse
Affiliation(s)
- Sonali A. Deshpande
- Department of Psychiatry and Biobehavioral Sciences, Hatos Center for Neuropharmacology, Gonda (Goldschmied) Neuroscience and Genetics Research Center, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Ethan W. Rohrbach
- Interdepartmental Program in Neuroscience, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - James D. Asuncion
- Medical Scientist Training Program, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Jenna Harrigan
- Interdepartmental Program in Molecular Toxicology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Aditya Eamani
- Department of Psychiatry and Biobehavioral Sciences, Hatos Center for Neuropharmacology, Gonda (Goldschmied) Neuroscience and Genetics Research Center, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Ellery H. Schlingmann
- Department of Psychiatry and Biobehavioral Sciences, Hatos Center for Neuropharmacology, Gonda (Goldschmied) Neuroscience and Genetics Research Center, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Daniel J. Suto
- Department of Psychiatry and Biobehavioral Sciences, Hatos Center for Neuropharmacology, Gonda (Goldschmied) Neuroscience and Genetics Research Center, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Pei-Tseng Lee
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Felix E. Schweizer
- Department of Neurobiology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
| | - Hugo J. Bellen
- Department of Molecular and Human Genetics, Department of Neuroscience, Baylor College of Medicine, Howard Hughes Medical Institute, Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, TX 77030, USA
| | - David E. Krantz
- Department of Psychiatry and Biobehavioral Sciences, Hatos Center for Neuropharmacology, Gonda (Goldschmied) Neuroscience and Genetics Research Center, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
- Corresponding author
| |
Collapse
|
21
|
Jaszczak JS, DeVault L, Jan LY, Jan YN. Steroid hormone signaling activates thermal nociception during Drosophila peripheral nervous system development. eLife 2022; 11:e76464. [PMID: 35353036 PMCID: PMC8967384 DOI: 10.7554/elife.76464] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 03/07/2022] [Indexed: 12/27/2022] Open
Abstract
Sensory neurons enable animals to detect environmental changes and avoid harm. An intriguing open question concerns how the various attributes of sensory neurons arise in development. Drosophila melanogaster larvae undergo a behavioral transition by robustly activating a thermal nociceptive escape behavior during the second half of larval development (third instar). The Class IV dendritic arborization (C4da) neurons are multimodal sensors which tile the body wall of Drosophila larvae and detect nociceptive temperature, light, and mechanical force. In contrast to the increase in nociceptive behavior in the third instar, we find that ultraviolet light-induced Ca2+ activity in C4da neurons decreases during the same period of larval development. Loss of ecdysone receptor has previously been shown to reduce nociception in third instar larvae. We find that ligand-dependent activation of ecdysone signaling is sufficient to promote nociceptive responses in second instar larvae and suppress expression of subdued (encoding a TMEM16 channel). Reduction of subdued expression in second instar C4da neurons not only increases thermal nociception but also decreases the response to ultraviolet light. Thus, steroid hormone signaling suppresses subdued expression to facilitate the sensory switch of C4da neurons. This regulation of a developmental sensory switch through steroid hormone regulation of channel expression raises the possibility that ion channel homeostasis is a key target for tuning the development of sensory modalities.
Collapse
Affiliation(s)
- Jacob S Jaszczak
- Department of Physiology, Department of Biochemistry and Biophysics, University of California, San FranciscoSan FranciscoUnited States
- Howard Hughes Medical InstituteChevy ChaseUnited States
| | - Laura DeVault
- Department of Physiology, Department of Biochemistry and Biophysics, University of California, San FranciscoSan FranciscoUnited States
- Department of Developmental Biology, Washington University Medical SchoolSaint LouisUnited States
| | - Lily Yeh Jan
- Department of Physiology, Department of Biochemistry and Biophysics, University of California, San FranciscoSan FranciscoUnited States
- Howard Hughes Medical InstituteChevy ChaseUnited States
| | - Yuh Nung Jan
- Department of Physiology, Department of Biochemistry and Biophysics, University of California, San FranciscoSan FranciscoUnited States
- Howard Hughes Medical InstituteChevy ChaseUnited States
| |
Collapse
|
22
|
He J, Li B, Han S, Zhang Y, Liu K, Yi S, Liu Y, Xiu M. Drosophila as a Model to Study the Mechanism of Nociception. Front Physiol 2022; 13:854124. [PMID: 35418874 PMCID: PMC8996152 DOI: 10.3389/fphys.2022.854124] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 02/28/2022] [Indexed: 12/15/2022] Open
Abstract
Nociception refers to the process of encoding and processing noxious stimuli, which allow animals to detect and avoid potentially harmful stimuli. Several types of stimuli can trigger nociceptive sensory transduction, including thermal, noxious chemicals, and harsh mechanical stimulation that depend on the corresponding nociceptors. In view of the high evolutionary conservation of the mechanisms that govern nociception from Drosophila melanogaster to mammals, investigation in the fruit fly Drosophila help us understand how the sensory nervous system works and what happen in nociception. Here, we present an overview of currently identified conserved genetics of nociception, the nociceptive sensory neurons responsible for detecting noxious stimuli, and various assays for evaluating different nociception. Finally, we cover development of anti-pain drug using fly model. These comparisons illustrate the value of using Drosophila as model for uncovering nociception mechanisms, which are essential for identifying new treatment goals and developing novel analgesics that are applicable to human health.
Collapse
Affiliation(s)
- Jianzheng He
- Provincial-Level Key Laboratory for Molecular Medicine of Major Diseases and the Prevention and Treatment with Traditional Chinese Medicine Research in Gansu Colleges and University, Gansu University of Chinese Medicine, Lanzhou, China
- College of Basic Medicine, Gansu University of Chinese Medicine, Lanzhou, China
- Key Laboratory for Transfer of Dunhuang Medicine at the Provincial and Ministerial Level, Gansu University of Chinese Medicine, Lanzhou, China
| | - Botong Li
- Provincial-Level Key Laboratory for Molecular Medicine of Major Diseases and the Prevention and Treatment with Traditional Chinese Medicine Research in Gansu Colleges and University, Gansu University of Chinese Medicine, Lanzhou, China
- College of Basic Medicine, Gansu University of Chinese Medicine, Lanzhou, China
| | - Shuzhen Han
- Provincial-Level Key Laboratory for Molecular Medicine of Major Diseases and the Prevention and Treatment with Traditional Chinese Medicine Research in Gansu Colleges and University, Gansu University of Chinese Medicine, Lanzhou, China
- College of Basic Medicine, Gansu University of Chinese Medicine, Lanzhou, China
| | - Yuan Zhang
- Provincial-Level Key Laboratory for Molecular Medicine of Major Diseases and the Prevention and Treatment with Traditional Chinese Medicine Research in Gansu Colleges and University, Gansu University of Chinese Medicine, Lanzhou, China
- College of Basic Medicine, Gansu University of Chinese Medicine, Lanzhou, China
| | - Kai Liu
- College of Integrated Traditional Chinese and Western Medicine, Gansu University of Chinese Medicine, Lanzhou, China
| | - Simeng Yi
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing, China
| | - Yongqi Liu
- Provincial-Level Key Laboratory for Molecular Medicine of Major Diseases and the Prevention and Treatment with Traditional Chinese Medicine Research in Gansu Colleges and University, Gansu University of Chinese Medicine, Lanzhou, China
- Key Laboratory for Transfer of Dunhuang Medicine at the Provincial and Ministerial Level, Gansu University of Chinese Medicine, Lanzhou, China
- *Correspondence: Yongqi Liu,
| | - Minghui Xiu
- Provincial-Level Key Laboratory for Molecular Medicine of Major Diseases and the Prevention and Treatment with Traditional Chinese Medicine Research in Gansu Colleges and University, Gansu University of Chinese Medicine, Lanzhou, China
- Key Laboratory for Transfer of Dunhuang Medicine at the Provincial and Ministerial Level, Gansu University of Chinese Medicine, Lanzhou, China
- College of Public Health, Gansu University of Chinese Medicine, Lanzhou, China
- Minghui Xiu,
| |
Collapse
|
23
|
Imambocus BN, Soba P. The elegance of prickly sensations. eLife 2022; 11:84161. [PMID: 36409070 PMCID: PMC9678355 DOI: 10.7554/elife.84161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Neurons sensing harmful mechanical forces in the larvae of fruit flies have a striking architecture of dendrites that are optimized to detect pointy objects.
Collapse
Affiliation(s)
- Bibi Nusreen Imambocus
- LIMES Institute, Department of Molecular Brain Physiology and Behavior, University of BonnBonnGermany
| | - Peter Soba
- LIMES Institute, Department of Molecular Brain Physiology and Behavior, University of BonnBonnGermany,Institute of Physiology and Pathophysiology, Friedrich-Alexander-Universität Erlangen-NürnbergErlangenGermany
| |
Collapse
|
24
|
Montell C. Drosophila sensory receptors-a set of molecular Swiss Army Knives. Genetics 2021; 217:1-34. [PMID: 33683373 DOI: 10.1093/genetics/iyaa011] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Accepted: 11/17/2020] [Indexed: 01/01/2023] Open
Abstract
Genetic approaches in the fruit fly, Drosophila melanogaster, have led to a major triumph in the field of sensory biology-the discovery of multiple large families of sensory receptors and channels. Some of these families, such as transient receptor potential channels, are conserved from animals ranging from worms to humans, while others, such as "gustatory receptors," "olfactory receptors," and "ionotropic receptors," are restricted to invertebrates. Prior to the identification of sensory receptors in flies, it was widely assumed that these proteins function in just one modality such as vision, smell, taste, hearing, and somatosensation, which includes thermosensation, light, and noxious mechanical touch. By employing a vast combination of genetic, behavioral, electrophysiological, and other approaches in flies, a major concept to emerge is that many sensory receptors are multitaskers. The earliest example of this idea was the discovery that individual transient receptor potential channels function in multiple senses. It is now clear that multitasking is exhibited by other large receptor families including gustatory receptors, ionotropic receptors, epithelial Na+ channels (also referred to as Pickpockets), and even opsins, which were formerly thought to function exclusively as light sensors. Genetic characterizations of these Drosophila receptors and the neurons that express them also reveal the mechanisms through which flies can accurately differentiate between different stimuli even when they activate the same receptor, as well as mechanisms of adaptation, amplification, and sensory integration. The insights gleaned from studies in flies have been highly influential in directing investigations in many other animal models.
Collapse
Affiliation(s)
- Craig Montell
- Department of Molecular, Cellular, and Developmental Biology, The Neuroscience Research Institute, University of California, Santa Barbara, CA 93106, USA
| |
Collapse
|
25
|
Abstract
Mechanosensing is a key feature through which organisms can receive inputs from the environment and convert them into specific functional and behavioral outputs. Mechanosensation occurs in many cells and tissues, regulating a plethora of molecular processes based on the distribution of forces and stresses both at the cell membrane and at the intracellular organelles levels, through complex interactions between cells’ microstructures, cytoskeleton, and extracellular matrix. Although several primary and secondary mechanisms have been shown to contribute to mechanosensation, a fundamental pathway in simple organisms and mammals involves the presence of specialized sensory neurons and the presence of different types of mechanosensitive ion channels on the neuronal cell membrane. In this contribution, we present a review of the main ion channels which have been proven to be significantly involved in mechanotransduction in neurons. Further, we discuss recent studies focused on the biological mechanisms and modeling of mechanosensitive ion channels’ gating, and on mechanotransduction modeling at different scales and levels of details.
Collapse
|
26
|
Gowda SBM, Salim S, Mohammad F. Anatomy and Neural Pathways Modulating Distinct Locomotor Behaviors in Drosophila Larva. BIOLOGY 2021; 10:90. [PMID: 33504061 PMCID: PMC7910854 DOI: 10.3390/biology10020090] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 12/07/2020] [Accepted: 12/30/2020] [Indexed: 11/17/2022]
Abstract
The control of movements is a fundamental feature shared by all animals. At the most basic level, simple movements are generated by coordinated neural activity and muscle contraction patterns that are controlled by the central nervous system. How behavioral responses to various sensory inputs are processed and integrated by the downstream neural network to produce flexible and adaptive behaviors remains an intense area of investigation in many laboratories. Due to recent advances in experimental techniques, many fundamental neural pathways underlying animal movements have now been elucidated. For example, while the role of motor neurons in locomotion has been studied in great detail, the roles of interneurons in animal movements in both basic and noxious environments have only recently been realized. However, the genetic and transmitter identities of many of these interneurons remains unclear. In this review, we provide an overview of the underlying circuitry and neural pathways required by Drosophila larvae to produce successful movements. By improving our understanding of locomotor circuitry in model systems such as Drosophila, we will have a better understanding of how neural circuits in organisms with different bodies and brains lead to distinct locomotion types at the organism level. The understanding of genetic and physiological components of these movements types also provides directions to understand movements in higher organisms.
Collapse
Affiliation(s)
| | | | - Farhan Mohammad
- Division of Biological and Biomedical Sciences (BBS), College of Health & Life Sciences (CHLS), Hamad Bin Khalifa University (HBKU), Doha 34110, Qatar; (S.B.M.G.); (S.S.)
| |
Collapse
|
27
|
Loss of Pseudouridine Synthases in the RluA Family Causes Hypersensitive Nociception in Drosophila. G3-GENES GENOMES GENETICS 2020; 10:4425-4438. [PMID: 33028630 PMCID: PMC7718762 DOI: 10.1534/g3.120.401767] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Nociceptive neurons of Drosophila melanogaster larvae are characterized by highly branched dendritic processes whose proper morphogenesis relies on a large number of RNA-binding proteins. Post-transcriptional regulation of RNA in these dendrites has been found to play an important role in their function. Here, we investigate the neuronal functions of two putative RNA modification genes, RluA-1 and RluA-2, which are predicted to encode pseudouridine synthases. RluA-1 is specifically expressed in larval sensory neurons while RluA-2 expression is ubiquitous. Nociceptor-specific RNAi knockdown of RluA-1 caused hypersensitive nociception phenotypes, which were recapitulated with genetic null alleles. These were rescued with genomic duplication and nociceptor-specific expression of UAS- RluA-1 -cDNA As with RluA-1, RluA-2 loss of function mutants also displayed hyperalgesia. Interestingly, nociceptor neuron dendrites showed a hyperbranched morphology in the RluA-1 mutants. The latter may be a cause or a consequence of heightened sensitivity in mutant nociception behaviors.
Collapse
|
28
|
Hehlert P, Zhang W, Göpfert MC. Drosophila Mechanosensory Transduction. Trends Neurosci 2020; 44:323-335. [PMID: 33257000 DOI: 10.1016/j.tins.2020.11.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 10/09/2020] [Accepted: 11/02/2020] [Indexed: 02/07/2023]
Abstract
Mechanosensation in Drosophila relies on sensory neurons transducing mechanical stimuli into ionic currents. The molecular mechanisms of this transduction are in the process of being revealed. Transduction relies on mechanogated ion channels that are activated by membrane stretch or the tension of force-conveying tethers. NOMPC (no-mechanoreceptor potential C) and DmPiezo were put forward as bona fide mechanoelectrical transduction (MET) channels, providing insights into MET channel architecture and the structural basis of mechanogating. Various additional channels were implicated in Drosophila mechanosensory neuron functions, and parallels between fly and vertebrate mechanotransduction were delineated. Collectively, these advances put forward Drosophila mechanosensory neurons as cellular paradigms for mechanotransduction and mechanogated ion channel function in the context of proprio- and nociception as well as the detection of substrate vibrations, touch, gravity, and sound.
Collapse
Affiliation(s)
- Philip Hehlert
- Department of Cellular Neurobiology, University of Göttingen, Julia-Lermontowa-Weg 3, 37077 Göttingen, Germany
| | - Wei Zhang
- School of Life Sciences, IDG/McGovern Institute for Brain Research, Tsinghua University, Beijing, 100084, China; Tsinghua-Peking Center for Life Sciences, Beijing, 100084, China; Chinese Institute for Brain Research, Beijing, 102206, China
| | - Martin C Göpfert
- Department of Cellular Neurobiology, University of Göttingen, Julia-Lermontowa-Weg 3, 37077 Göttingen, Germany; Collaborative Research Center 889, University of Göttingen, 37075 Göttingen, Germany; Multiscale Bioimaging Cluster of Excellence (MBExC), University of Göttingen, Göttingen, Germany.
| |
Collapse
|
29
|
Dannhäuser S, Lux TJ, Hu C, Selcho M, Chen JTC, Ehmann N, Sachidanandan D, Stopp S, Pauls D, Pawlak M, Langenhan T, Soba P, Rittner HL, Kittel RJ. Antinociceptive modulation by the adhesion GPCR CIRL promotes mechanosensory signal discrimination. eLife 2020; 9:e56738. [PMID: 32996461 PMCID: PMC7546736 DOI: 10.7554/elife.56738] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 09/17/2020] [Indexed: 12/17/2022] Open
Abstract
Adhesion-type GPCRs (aGPCRs) participate in a vast range of physiological processes. Their frequent association with mechanosensitive functions suggests that processing of mechanical stimuli may be a common feature of this receptor family. Previously, we reported that the Drosophila aGPCR CIRL sensitizes sensory responses to gentle touch and sound by amplifying signal transduction in low-threshold mechanoreceptors (Scholz et al., 2017). Here, we show that Cirl is also expressed in high-threshold mechanical nociceptors where it adjusts nocifensive behaviour under physiological and pathological conditions. Optogenetic in vivo experiments indicate that CIRL lowers cAMP levels in both mechanosensory submodalities. However, contrasting its role in touch-sensitive neurons, CIRL dampens the response of nociceptors to mechanical stimulation. Consistent with this finding, rat nociceptors display decreased Cirl1 expression during allodynia. Thus, cAMP-downregulation by CIRL exerts opposing effects on low-threshold mechanosensors and high-threshold nociceptors. This intriguing bipolar action facilitates the separation of mechanosensory signals carrying different physiological information.
Collapse
Affiliation(s)
- Sven Dannhäuser
- Department of Animal Physiology, Institute of Biology, Leipzig UniversityLeipzigGermany
- Carl-Ludwig-Institute for Physiology, Leipzig UniversityLeipzigGermany
| | - Thomas J Lux
- Center for Interdisciplinary Pain Medicine, Department of Anaesthesiology, University Hospital WürzburgWürzburgGermany
| | - Chun Hu
- Neuronal Patterning and Connectivity, Center for Molecular Neurobiology, University Medical Center Hamburg-EppendorfHamburgGermany
| | - Mareike Selcho
- Department of Animal Physiology, Institute of Biology, Leipzig UniversityLeipzigGermany
- Carl-Ludwig-Institute for Physiology, Leipzig UniversityLeipzigGermany
| | - Jeremy T-C Chen
- Center for Interdisciplinary Pain Medicine, Department of Anaesthesiology, University Hospital WürzburgWürzburgGermany
| | - Nadine Ehmann
- Department of Animal Physiology, Institute of Biology, Leipzig UniversityLeipzigGermany
- Carl-Ludwig-Institute for Physiology, Leipzig UniversityLeipzigGermany
| | - Divya Sachidanandan
- Department of Animal Physiology, Institute of Biology, Leipzig UniversityLeipzigGermany
- Carl-Ludwig-Institute for Physiology, Leipzig UniversityLeipzigGermany
| | - Sarah Stopp
- Department of Animal Physiology, Institute of Biology, Leipzig UniversityLeipzigGermany
- Carl-Ludwig-Institute for Physiology, Leipzig UniversityLeipzigGermany
| | - Dennis Pauls
- Department of Animal Physiology, Institute of Biology, Leipzig UniversityLeipzigGermany
- Carl-Ludwig-Institute for Physiology, Leipzig UniversityLeipzigGermany
| | - Matthias Pawlak
- Department of Neurophysiology, Institute of Physiology, University of WürzburgWürzburgGermany
| | - Tobias Langenhan
- Rudolf Schönheimer Institute of Biochemistry, Division of General Biochemistry, Medical Faculty, Leipzig UniversityLeipzigGermany
| | - Peter Soba
- Neuronal Patterning and Connectivity, Center for Molecular Neurobiology, University Medical Center Hamburg-EppendorfHamburgGermany
| | - Heike L Rittner
- Center for Interdisciplinary Pain Medicine, Department of Anaesthesiology, University Hospital WürzburgWürzburgGermany
| | - Robert J Kittel
- Department of Animal Physiology, Institute of Biology, Leipzig UniversityLeipzigGermany
- Carl-Ludwig-Institute for Physiology, Leipzig UniversityLeipzigGermany
| |
Collapse
|
30
|
Gupta A, Stocker H. FoxO suppresses endoplasmic reticulum stress to inhibit growth of Tsc1-deficient tissues under nutrient restriction. eLife 2020; 9:53159. [PMID: 32525804 PMCID: PMC7289595 DOI: 10.7554/elife.53159] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 05/22/2020] [Indexed: 12/27/2022] Open
Abstract
The transcription factor FoxO has been shown to block proliferation and progression in mTORC1-driven tumorigenesis but the picture of the relevant FoxO target genes remains incomplete. Here, we employed RNA-seq profiling on single clones isolated using laser capture microdissection from Drosophila larval eye imaginal discs to identify FoxO targets that restrict the proliferation of Tsc1-deficient cells under nutrient restriction (NR). Transcriptomics analysis revealed downregulation of endoplasmic reticulum-associated protein degradation pathway components upon foxo knockdown. Induction of ER stress pharmacologically or by suppression of other ER stress response pathway components led to an enhanced overgrowth of Tsc1 knockdown tissue. Increase of ER stress in Tsc1 loss-of-function cells upon foxo knockdown was also confirmed by elevated expression levels of known ER stress markers. These results highlight the role of FoxO in limiting ER stress to regulate Tsc1 mutant overgrowth.
Collapse
Affiliation(s)
- Avantika Gupta
- Institute of Molecular Systems Biology, ETH Zürich, Zürich, Switzerland
| | - Hugo Stocker
- Institute of Molecular Systems Biology, ETH Zürich, Zürich, Switzerland
| |
Collapse
|
31
|
Hu C, Kanellopoulos AK, Richter M, Petersen M, Konietzny A, Tenedini FM, Hoyer N, Cheng L, Poon CLC, Harvey KF, Windhorst S, Parrish JZ, Mikhaylova M, Bagni C, Calderon de Anda F, Soba P. Conserved Tao Kinase Activity Regulates Dendritic Arborization, Cytoskeletal Dynamics, and Sensory Function in Drosophila. J Neurosci 2020; 40:1819-1833. [PMID: 31964717 PMCID: PMC7046460 DOI: 10.1523/jneurosci.1846-19.2020] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 01/13/2020] [Accepted: 01/16/2020] [Indexed: 12/11/2022] Open
Abstract
Dendritic arborization is highly regulated and requires tight control of dendritic growth, branching, cytoskeletal dynamics, and ion channel expression to ensure proper function. Abnormal dendritic development can result in altered network connectivity, which has been linked to neurodevelopmental disorders, including autism spectrum disorders (ASDs). How neuronal growth control programs tune dendritic arborization to ensure function is still not fully understood. Using Drosophila dendritic arborization (da) neurons as a model, we identified the conserved Ste20-like kinase Tao as a negative regulator of dendritic arborization. We show that Tao kinase activity regulates cytoskeletal dynamics and sensory channel localization required for proper sensory function in both male and female flies. We further provide evidence for functional conservation of Tao kinase, showing that its ASD-linked human ortholog, Tao kinase 2 (Taok2), could replace Drosophila Tao and rescue dendritic branching, dynamic microtubule alterations, and behavioral defects. However, several ASD-linked Taok2 variants displayed impaired rescue activity, suggesting that Tao/Taok2 mutations can disrupt sensory neuron development and function. Consistently, we show that Tao kinase activity is required in developing and as well as adult stages for maintaining normal dendritic arborization and sensory function to regulate escape and social behavior. Our data suggest an important role for Tao kinase signaling in cytoskeletal organization to maintain proper dendritic arborization and sensory function, providing a strong link between developmental sensory aberrations and behavioral abnormalities relevant for Taok2-dependent ASDs.SIGNIFICANCE STATEMENT Autism spectrum disorders (ASDs) are linked to abnormal dendritic arbors. However, the mechanisms of how dendritic arbors develop to promote functional and proper behavior are unclear. We identified Drosophila Tao kinase, the ortholog of the ASD risk gene Taok2, as a regulator of dendritic arborization in sensory neurons. We show that Tao kinase regulates cytoskeletal dynamics, controls sensory ion channel localization, and is required to maintain somatosensory function in vivo Interestingly, ASD-linked human Taok2 mutations rendered it nonfunctional, whereas its WT form could restore neuronal morphology and function in Drosophila lacking endogenous Tao. Our findings provide evidence for a conserved role of Tao kinase in dendritic development and function of sensory neurons, suggesting that aberrant sensory function might be a common feature of ASDs.
Collapse
Affiliation(s)
- Chun Hu
- Neuronal Patterning and Connectivity Laboratory, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | | | - Melanie Richter
- Neuronal Development Laboratory, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Meike Petersen
- Neuronal Patterning and Connectivity Laboratory, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Anja Konietzny
- Neuronal Protein Transport Laboratory, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Federico M Tenedini
- Neuronal Patterning and Connectivity Laboratory, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Nina Hoyer
- Neuronal Patterning and Connectivity Laboratory, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Lin Cheng
- Neuronal Patterning and Connectivity Laboratory, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Carole L C Poon
- Peter MacCallum Cancer Centre, Melbourne, 3000 Victoria, Australia
| | - Kieran F Harvey
- Peter MacCallum Cancer Centre, Melbourne, 3000 Victoria, Australia
- Department of Anatomy and Developmental Biology, and Biomedicine Discovery Institute, Monash University, Clayton, 3800 Victoria, Australia
| | - Sabine Windhorst
- Center for Experimental Medicine, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Jay Z Parrish
- Department of Biology, University of Washington, Seattle, 98195 Washington, and
| | - Marina Mikhaylova
- Neuronal Protein Transport Laboratory, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Claudia Bagni
- Department of Fundamental Neurosciences, University of Lausanne, 1005 Lausanne, Switzerland
- Department of Biomedicine and Prevention, University of Rome Tor Vergata, 00133 Rome, Italy
| | - Froylan Calderon de Anda
- Neuronal Development Laboratory, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Peter Soba
- Neuronal Patterning and Connectivity Laboratory, Center for Molecular Neurobiology (ZMNH), University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany,
| |
Collapse
|
32
|
Caron DP, Rimniceanu M, Scibelli AE, Trimmer BA. Nociceptive neurons respond to multimodal stimuli in Manduca sexta. J Exp Biol 2020; 223:jeb218859. [PMID: 31932302 DOI: 10.1242/jeb.218859] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 01/06/2020] [Indexed: 12/14/2022]
Abstract
The caterpillar Manduca sexta produces a highly stereotyped strike behavior in response to noxious thermal or mechanical stimuli to the abdomen. This rapid movement is targeted to the site of the stimulus, but the identity of the nociceptive sensory neurons are currently unknown. It is also not known whether both mechanical and thermal stimuli are detected by the same neurons. Here, we show that the likelihood of a strike increases with the strength of the stimulus and that activity in nerves innervating the body wall increases rapidly in response to noxious stimuli. Mechanical and thermal stimuli to the dorsal body wall activate the same sensory unit, suggesting it represents a multimodal neuron. This is further supported by the effects of rapidly repeated thermal or mechanical stimuli, which cause a depression of neuronal responsiveness that is generalized across modalities. Mapping the receptive fields of neurons responding to strong thermal stimuli indicates that these multimodal, nociceptive units are produced by class γ multidendritic neurons in the body wall.
Collapse
Affiliation(s)
- Daniel P Caron
- Tufts University, Department of Biology, 200 Boston Avenue, Suite 2600, Medford, MA 02155, USA
| | - Martha Rimniceanu
- Tufts University, Department of Biology, 200 Boston Avenue, Suite 2600, Medford, MA 02155, USA
| | - Anthony E Scibelli
- Tufts University, Department of Biology, 200 Boston Avenue, Suite 2600, Medford, MA 02155, USA
| | - Barry A Trimmer
- Tufts University, Department of Biology, 200 Boston Avenue, Suite 2600, Medford, MA 02155, USA
| |
Collapse
|
33
|
Walcott KCE, Mauthner SE, Tsubouchi A, Robertson J, Tracey WD. The Drosophila Small Conductance Calcium-Activated Potassium Channel Negatively Regulates Nociception. Cell Rep 2019; 24:3125-3132.e3. [PMID: 30231996 PMCID: PMC6454897 DOI: 10.1016/j.celrep.2018.08.070] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2014] [Revised: 06/11/2018] [Accepted: 08/23/2018] [Indexed: 12/20/2022] Open
Abstract
Inhibition of nociceptor activity is important for the prevention of spontaneous pain and hyperalgesia. To identify the critical K+ channels that regulate nociceptor excitability, we performed a forward genetic screen using a Drosophila larval nociception paradigm. Knockdown of three K+ channel loci, the small conductance calcium-activated potassium channel (SK), seizure, and tiwaz, causes marked hypersensitive nociception behaviors. In more detailed studies of SK, we found that hypersensitive phenotypes can be recapitulated with a genetically null allele. Optical recordings from nociceptive neurons showed a significant increase in mechanically activated Ca2+ signals in SK mutant nociceptors. SK is expressed in peripheral neurons, including nociceptive neurons. Interestingly, SK proteins localize to axons of these neurons but are not detected in dendrites. Our findings suggest a major role for SK channels in the regulation of nociceptor excitation and are inconsistent with the hypothesis that the important site of action is within dendrites. Walcott et al. performed a forward genetic screen and identify three potassium channel subunits that negatively regulate nociception in Drosophila larvae. In a more detailed investigation of the SK channel, null mutants, rescue experiments, optical recordings, and protein localization studies indicate a functional role for SK in nociceptor excitability.
Collapse
Affiliation(s)
- Kia C E Walcott
- Department of Pharmacology and Cancer Biology, Duke University Medical Center, Durham, NC, USA
| | - Stephanie E Mauthner
- Gill Center for Biomolecular Research, Indiana University, Bloomington, IN, USA; Department of Biology, Indiana University, Bloomington, IN, USA
| | - Asako Tsubouchi
- Department of Anesthesiology, Duke University Medical Center, Durham, NC, USA
| | - Jessica Robertson
- Department of Cell Biology, Duke University Medical Center, Durham, NC, USA
| | - W Daniel Tracey
- Gill Center for Biomolecular Research, Indiana University, Bloomington, IN, USA; Department of Biology, Indiana University, Bloomington, IN, USA; Department of Anesthesiology, Duke University Medical Center, Durham, NC, USA; Department of Cell Biology, Duke University Medical Center, Durham, NC, USA.
| |
Collapse
|
34
|
Krämer R, Rode S, Rumpf S. Rab11 is required for neurite pruning and developmental membrane protein degradation in Drosophila sensory neurons. Dev Biol 2019; 451:68-78. [DOI: 10.1016/j.ydbio.2019.03.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 03/05/2019] [Accepted: 03/05/2019] [Indexed: 12/11/2022]
|
35
|
Drosophila melanogaster foraging regulates a nociceptive-like escape behavior through a developmentally plastic sensory circuit. Proc Natl Acad Sci U S A 2019; 117:23286-23291. [PMID: 31213548 DOI: 10.1073/pnas.1820840116] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Painful or threatening experiences trigger escape responses that are guided by nociceptive neuronal circuitry. Although some components of this circuitry are known and conserved across animals, how this circuitry is regulated at the genetic and developmental levels is mostly unknown. To escape noxious stimuli, such as parasitoid wasp attacks, Drosophila melanogaster larvae generate a curling and rolling response. Rover and sitter allelic variants of the Drosophila foraging (for) gene differ in parasitoid wasp susceptibility, suggesting a link between for and nociception. By optogenetically activating cells associated with each of for's promoters (pr1-pr4), we show that pr1 cells regulate larval escape behavior. In accordance with rover and sitter differences in parasitoid wasp susceptibility, we found that rovers have higher pr1 expression and increased sensitivity to nociception relative to sitters. The for null mutants display impaired responses to thermal nociception, which are rescued by restoring for expression in pr1 cells. Conversely, knockdown of for in pr1 cells phenocopies the for null mutant. To gain insight into the circuitry underlying this response, we used an intersectional approach and activity-dependent GFP reconstitution across synaptic partners (GRASP) to show that pr1 cells in the ventral nerve cord (VNC) are required for the nociceptive response, and that multidendritic sensory nociceptive neurons synapse onto pr1 neurons in the VNC. Finally, we show that activation of the pr1 circuit during development suppresses the escape response. Our data demonstrate a role of for in larval nociceptive behavior. This function is specific to for pr1 neurons in the VNC, guiding a developmentally plastic escape response circuit.
Collapse
|
36
|
Jang W, Lee S, Choi SI, Chae HS, Han J, Jo H, Hwang SW, Park CS, Kim C. Impairment of proprioceptive movement and mechanical nociception in Drosophila melanogaster larvae lacking Ppk30, a Drosophila member of the Degenerin/Epithelial Sodium Channel family. GENES BRAIN AND BEHAVIOR 2019; 18:e12545. [PMID: 30675754 DOI: 10.1111/gbb.12545] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2018] [Revised: 12/07/2018] [Indexed: 12/23/2022]
Abstract
The mechanosensory neurons of Drosophila larvae are demonstrably activated by diverse mechanical stimuli, but the mechanisms underlying this function are not completely understood. Here we report a genetic, immunohistochemical, and electrophysiological analysis of the Ppk30 ion channel, a member of the Drosophila pickpocket (ppk) family, counterpart of the mammalian Degenerin/Epithelial Na+ Channel family. Ppk30 mutant larvae displayed deficits in proprioceptive movement and mechanical nociception, which are detected by class IV sensory (mdIV) neurons. The same neurons also detect heat nociception, which was not impaired in ppk30 mutant larvae. Similarly, Ppk30 mutation did not alter gentle touch mechanosensation, a distinct mechanosensation detected by other neurons, suggesting that Ppk30 has a functional role in mechanosensation in mdIV neurons. Consistently, Ppk30 was expressed in class IV neurons, but was not detectable in other larval skin sensory neurons. Mutant phenotypes were rescued by expressing Ppk30 in mdIV neurons. Electrophysiological analysis of heterologous cells expressing Ppk30 did not detect mechanosensitive channel activities, but did detect acid-induced currents. These data show that Ppk30 has a role in mechanosensation, but not in thermosensation, in class IV neurons, and possibly has other functions related to acid response.
Collapse
Affiliation(s)
- Wijeong Jang
- School of Biological Sciences and technology, Chonnam National University, Gwangju, Republic of Korea
| | - Sojung Lee
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea
| | - Seung-In Choi
- Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea
| | - Hyo-Seok Chae
- School of Biological Sciences and technology, Chonnam National University, Gwangju, Republic of Korea
| | - Jisun Han
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea
| | - Heeji Jo
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea
| | - Sun W Hwang
- Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Republic of Korea
| | - Chul-Seung Park
- School of Life Sciences, Gwangju Institute of Science and Technology (GIST), Gwangju, Republic of Korea
| | - Changsoo Kim
- School of Biological Sciences and technology, Chonnam National University, Gwangju, Republic of Korea
| |
Collapse
|
37
|
Herman JA, Willits AB, Bellemer A. Gαq and Phospholipase Cβ signaling regulate nociceptor sensitivity in Drosophila melanogaster larvae. PeerJ 2018; 6:e5632. [PMID: 30258723 PMCID: PMC6151255 DOI: 10.7717/peerj.5632] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2018] [Accepted: 08/24/2018] [Indexed: 12/29/2022] Open
Abstract
Drosophila melanogaster larvae detect noxious thermal and mechanical stimuli in their environment using polymodal nociceptor neurons whose dendrites tile the larval body wall. Activation of these nociceptors by potentially tissue-damaging stimuli elicits a stereotyped escape locomotion response. The cellular and molecular mechanisms that regulate nociceptor function are increasingly well understood, but gaps remain in our knowledge of the broad mechanisms that control nociceptor sensitivity. In this study, we use cell-specific knockdown and overexpression to show that nociceptor sensitivity to noxious thermal and mechanical stimuli is correlated with levels of Gαq and phospholipase Cβ signaling. Genetic manipulation of these signaling mechanisms does not result in changes in nociceptor morphology, suggesting that changes in nociceptor function do not arise from changes in nociceptor development, but instead from changes in nociceptor activity. These results demonstrate roles for Gαq and phospholipase Cβ signaling in facilitating the basal sensitivity of the larval nociceptors to noxious thermal and mechanical stimuli and suggest future studies to investigate how these signaling mechanisms may participate in neuromodulation of sensory function.
Collapse
Affiliation(s)
- Joshua A Herman
- Department of Biology, Appalachian State University, Boone, NC, United States of America
| | - Adam B Willits
- Department of Biology, Appalachian State University, Boone, NC, United States of America
| | - Andrew Bellemer
- Department of Biology, Appalachian State University, Boone, NC, United States of America
| |
Collapse
|
38
|
Walters ET. Nociceptive Biology of Molluscs and Arthropods: Evolutionary Clues About Functions and Mechanisms Potentially Related to Pain. Front Physiol 2018; 9:1049. [PMID: 30123137 PMCID: PMC6085516 DOI: 10.3389/fphys.2018.01049] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Accepted: 07/16/2018] [Indexed: 01/15/2023] Open
Abstract
Important insights into the selection pressures and core molecular modules contributing to the evolution of pain-related processes have come from studies of nociceptive systems in several molluscan and arthropod species. These phyla, and the chordates that include humans, last shared a common ancestor approximately 550 million years ago. Since then, animals in these phyla have continued to be subject to traumatic injury, often from predators, which has led to similar adaptive behaviors (e.g., withdrawal, escape, recuperative behavior) and physiological responses to injury in each group. Comparisons across these taxa provide clues about the contributions of convergent evolution and of conservation of ancient adaptive mechanisms to general nociceptive and pain-related functions. Primary nociceptors have been investigated extensively in a few molluscan and arthropod species, with studies of long-lasting nociceptive sensitization in the gastropod, Aplysia, and the insect, Drosophila, being especially fruitful. In Aplysia, nociceptive sensitization has been investigated as a model for aversive memory and for hyperalgesia. Neuromodulator-induced, activity-dependent, and axotomy-induced plasticity mechanisms have been defined in synapses, cell bodies, and axons of Aplysia primary nociceptors. Studies of nociceptive sensitization in Drosophila larvae have revealed numerous molecular contributors in primary nociceptors and interacting cells. Interestingly, molecular contributors examined thus far in Aplysia and Drosophila are largely different, but both sets overlap extensively with those in mammalian pain-related pathways. In contrast to results from Aplysia and Drosophila, nociceptive sensitization examined in moth larvae (Manduca) disclosed central hyperactivity but no obvious peripheral sensitization of nociceptive responses. Squid (Doryteuthis) show injury-induced sensitization manifested as behavioral hypersensitivity to tactile and especially visual stimuli, and as hypersensitivity and spontaneous activity in nociceptor terminals. Temporary blockade of nociceptor activity during injury subsequently increased mortality when injured squid were exposed to fish predators, providing the first demonstration in any animal of the adaptiveness of nociceptive sensitization. Immediate responses to noxious stimulation and nociceptive sensitization have also been examined behaviorally and physiologically in a snail (Helix), octopus (Adopus), crayfish (Astacus), hermit crab (Pagurus), and shore crab (Hemigrapsus). Molluscs and arthropods have systems that suppress nociceptive responses, but whether opioid systems play antinociceptive roles in these phyla is uncertain.
Collapse
Affiliation(s)
- Edgar T Walters
- Department of Integrative Biology and Pharmacology, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, TX, United States
| |
Collapse
|
39
|
Abstract
Nociception, the sensory mechanism that allows animals to sense and avoid potentially tissue-damaging stimuli, is critical for survival. This process relies on nociceptors, which are specialized neurons that detect and respond to potentially damaging forms of energy - heat, mechanical and chemical - in the environment. Nociceptors accomplish this task through the expression of molecules that function to detect and signal the presence of potential harm. Downstream of the nociceptive sensory input, the neural signals trigger protective (nocifensive) behaviors, and the sensory stimuli that reach the brain may be perceived as painful.
Collapse
|
40
|
Orr BO, Gorczyca D, Younger MA, Jan LY, Jan YN, Davis GW. Composition and Control of a Deg/ENaC Channel during Presynaptic Homeostatic Plasticity. Cell Rep 2018; 20:1855-1866. [PMID: 28834749 DOI: 10.1016/j.celrep.2017.07.074] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2017] [Revised: 04/10/2017] [Accepted: 07/25/2017] [Indexed: 01/08/2023] Open
Abstract
The homeostatic control of presynaptic neurotransmitter release stabilizes information transfer at synaptic connections in the nervous system of organisms ranging from insect to human. Presynaptic homeostatic signaling centers upon the regulated membrane insertion of an amiloride-sensitive degenerin/epithelial sodium (Deg/ENaC) channel. Elucidating the subunit composition of this channel is an essential step toward defining the underlying mechanisms of presynaptic homeostatic plasticity (PHP). Here, we demonstrate that the ppk1 gene encodes an essential subunit of this Deg/ENaC channel, functioning in motoneurons for the rapid induction and maintenance of PHP. We provide genetic and biochemical evidence that PPK1 functions together with PPK11 and PPK16 as a presynaptic, hetero-trimeric Deg/ENaC channel. Finally, we highlight tight control of Deg/ENaC channel expression and activity, showing increased PPK1 protein expression during PHP and evidence for signaling mechanisms that fine tune the level of Deg/ENaC activity during PHP.
Collapse
Affiliation(s)
- Brian O Orr
- Department of Biochemistry and Biophysics, Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, San Francisco, CA 94158, USA
| | - David Gorczyca
- Howard Hughes Medical Institute, Department of Physiology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Meg A Younger
- Department of Biochemistry and Biophysics, Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Lily Y Jan
- Howard Hughes Medical Institute, Department of Physiology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Yuh-Nung Jan
- Howard Hughes Medical Institute, Department of Physiology, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Graeme W Davis
- Department of Biochemistry and Biophysics, Kavli Institute for Fundamental Neuroscience, University of California, San Francisco, San Francisco, CA 94158, USA.
| |
Collapse
|
41
|
DeVault L, Li T, Izabel S, Thompson-Peer KL, Jan LY, Jan YN. Dendrite regeneration of adult Drosophila sensory neurons diminishes with aging and is inhibited by epidermal-derived matrix metalloproteinase 2. Genes Dev 2018; 32:402-414. [PMID: 29563183 PMCID: PMC5900713 DOI: 10.1101/gad.308270.117] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2017] [Accepted: 02/26/2018] [Indexed: 11/30/2022]
Abstract
DeVault et al. show that the capacity for regeneration was present in adult neurons but diminished as the animal aged. The regenerated dendrites showed preferential alignment with the extracellular matrix, and inhibition of matrix metalloproteinase 2 led to increased dendrite regeneration. Dendrites possess distinct structural and functional properties that enable neurons to receive information from the environment as well as other neurons. Despite their key role in neuronal function, current understanding of the ability of neurons to regenerate dendrites is lacking. This study characterizes the structural and functional capacity for dendrite regeneration in vivo in adult animals and examines the effect of neuronal maturation on dendrite regeneration. We focused on the class IV dendritic arborization (c4da) neuron of the Drosophila sensory system, which has a dendritic arbor that undergoes dramatic remodeling during the first 3 d of adult life and then maintains a relatively stable morphology thereafter. Using a laser severing paradigm, we monitored regeneration after acute and spatially restricted injury. We found that the capacity for regeneration was present in adult neurons but diminished as the animal aged. Regenerated dendrites recovered receptive function. Furthermore, we found that the regenerated dendrites show preferential alignment with the extracellular matrix (ECM). Finally, inhibition of ECM degradation by inhibition of matrix metalloproteinase 2 (Mmp2) to preserve the extracellular environment characteristics of young adults led to increased dendrite regeneration. These results demonstrate that dendrites retain regenerative potential throughout adulthood and that regenerative capacity decreases with aging.
Collapse
Affiliation(s)
- Laura DeVault
- Howard Hughes Medical Institute, Department of Physiology, Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, California 94158, USA
| | - Tun Li
- Howard Hughes Medical Institute, Department of Physiology, Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, California 94158, USA
| | - Sarah Izabel
- Howard Hughes Medical Institute, Department of Physiology, Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, California 94158, USA
| | - Katherine L Thompson-Peer
- Howard Hughes Medical Institute, Department of Physiology, Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, California 94158, USA
| | - Lily Yeh Jan
- Howard Hughes Medical Institute, Department of Physiology, Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, California 94158, USA
| | - Yuh Nung Jan
- Howard Hughes Medical Institute, Department of Physiology, Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, California 94158, USA
| |
Collapse
|
42
|
Tsubouchi A, Yano T, Yokoyama TK, Murtin C, Otsuna H, Ito K. Topological and modality-specific representation of somatosensory information in the fly brain. Science 2018; 358:615-623. [PMID: 29097543 DOI: 10.1126/science.aan4428] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Accepted: 09/25/2017] [Indexed: 12/11/2022]
Abstract
Insects and mammals share similarities of neural organization underlying the perception of odors, taste, vision, sound, and gravity. We observed that insect somatosensation also corresponds to that of mammals. In Drosophila, the projections of all the somatosensory neuron types to the insect's equivalent of the spinal cord segregated into modality-specific layers comparable to those in mammals. Some sensory neurons innervate the ventral brain directly to form modality-specific and topological somatosensory maps. Ascending interneurons with dendrites in matching layers of the nerve cord send axons that converge to respective brain regions. Pathways arising from leg somatosensory neurons encode distinct qualities of leg movement information and play different roles in ground detection. Establishment of the ground pattern and genetic tools for neuronal manipulation should provide the basis for elucidating the mechanisms underlying somatosensation.
Collapse
Affiliation(s)
- Asako Tsubouchi
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Yayoi, Bunkyo-ku, 113-0032 Tokyo, Japan
| | - Tomoko Yano
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Yayoi, Bunkyo-ku, 113-0032 Tokyo, Japan.,Department of Computational Biology, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwanoha, Kashiwa, 277-0882 Chiba, Japan
| | - Takeshi K Yokoyama
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Yayoi, Bunkyo-ku, 113-0032 Tokyo, Japan
| | - Chloé Murtin
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Yayoi, Bunkyo-ku, 113-0032 Tokyo, Japan.,Department of Computational Biology, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwanoha, Kashiwa, 277-0882 Chiba, Japan
| | - Hideo Otsuna
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA 20147, USA
| | - Kei Ito
- Institute of Molecular and Cellular Biosciences, The University of Tokyo, Yayoi, Bunkyo-ku, 113-0032 Tokyo, Japan. .,Department of Computational Biology, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwanoha, Kashiwa, 277-0882 Chiba, Japan.,Howard Hughes Medical Institute, Janelia Research Campus, Ashburn, VA 20147, USA.,Institute of Zoology, University of Cologne, 50674 Cologne, Germany
| |
Collapse
|
43
|
Hoyer N, Petersen M, Tenedini F, Soba P. Assaying Mechanonociceptive Behavior in Drosophila Larvae. Bio Protoc 2018; 8:e2736. [PMID: 34179264 DOI: 10.21769/bioprotoc.2736] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 01/26/2018] [Accepted: 02/01/2018] [Indexed: 11/02/2022] Open
Abstract
Drosophila melanogaster larvae have been extensively used as a model to study the molecular and cellular basis of nociception. The larval nociceptors, class IV dendritic arborization (C4da) neurons, line the body wall of the animal and respond to various stimuli including noxious heat and touch. Activation of C4da neurons results in a stereotyped escape behavior, characterized by a 360° rolling response along the body axis followed by locomotion speedup. The genetic accessibility of Drosophila has allowed the identification of mechanosensory channels and circuit elements required for nociceptive responses, making it a useful and straightforward readout to understand the cellular and molecular basis of nociceptive function and behavior. We have optimized the protocol to assay mechanonociceptive behavior in Drosophila larvae.
Collapse
Affiliation(s)
- Nina Hoyer
- Research Group Neuronal Patterning and Connectivity, Center for Molecular Neurobiology (ZMNH), University Medical Campus Hamburg-Eppendorf, Hamburg, Germany
| | - Meike Petersen
- Research Group Neuronal Patterning and Connectivity, Center for Molecular Neurobiology (ZMNH), University Medical Campus Hamburg-Eppendorf, Hamburg, Germany
| | - Federico Tenedini
- Research Group Neuronal Patterning and Connectivity, Center for Molecular Neurobiology (ZMNH), University Medical Campus Hamburg-Eppendorf, Hamburg, Germany
| | - Peter Soba
- Research Group Neuronal Patterning and Connectivity, Center for Molecular Neurobiology (ZMNH), University Medical Campus Hamburg-Eppendorf, Hamburg, Germany
| |
Collapse
|
44
|
Bevilacqua C, Ducos B. Laser microdissection: A powerful tool for genomics at cell level. Mol Aspects Med 2017; 59:5-27. [PMID: 28927943 DOI: 10.1016/j.mam.2017.09.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 09/13/2017] [Indexed: 12/18/2022]
Abstract
Laser microdissection (LM) has become widely democratized over the last fifteen years. Instruments have evolved to offer more powerful and efficient lasers as well as new options for sample collection and preparation. Technological evolutions have also focused on the post-microdissection analysis capabilities, opening up investigations in all disciplines of experimental and clinical biology, thanks to the advent of new high-throughput methods of genome analysis, including RNAseq and proteomics, now globally known as microgenomics, i.e. analysis of biomolecules at the cell level. In spite of the advances these rapidly developing methods have allowed, the workflow for sampling and collection by LM remains a critical step in insuring sample integrity in terms of histology (accurate cell identification) and biochemistry (reliable analyzes of biomolecules). In this review, we describe the sample processing as well as the strengths and limiting factors of LM applied to the specific selection of one or more cells of interest from a heterogeneous tissue. We will see how the latest developments in protocols and methods have made LM a powerful and sometimes essential tool for genomic and proteomic analyzes of tiny amounts of biomolecules extracted from few cells isolated from a complex tissue, in their physiological context, thus offering new opportunities for understanding fundamental physiological and/or patho-physiological processes.
Collapse
Affiliation(s)
- Claudia Bevilacqua
- GABI, Plateforme @BRIDGE, INRA, AgroParisTech, Université Paris-Saclay, Domaine de Vilvert, 78350 Jouy en Josas, France.
| | - Bertrand Ducos
- LPS-ENS, CNRS UMR 8550, UPMC, Université Denis Diderot, PSL Research University, 24 Rue Lhomond, 75005 Paris France; High Throughput qPCR Core Facility, IBENS, 46 Rue d'Ulm, 75005 Paris France; Laser Microdissection Facility of Montagne Sainte Geneviève, CIRB Collège de France, Place Marcellin Berthelot, 75005 Paris France.
| |
Collapse
|
45
|
Yoshino J, Morikawa RK, Hasegawa E, Emoto K. Neural Circuitry that Evokes Escape Behavior upon Activation of Nociceptive Sensory Neurons in Drosophila Larvae. Curr Biol 2017; 27:2499-2504.e3. [PMID: 28803873 DOI: 10.1016/j.cub.2017.06.068] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Revised: 05/31/2017] [Accepted: 06/27/2017] [Indexed: 12/11/2022]
Abstract
Noxious stimuli trigger a stereotyped escape response in animals. In Drosophila larvae, class IV dendrite arborization (C4 da) sensory neurons in the peripheral nervous system are responsible for perception of multiple nociceptive modalities, including noxious heat and harsh mechanical stimulation, through distinct receptors [1-9]. Silencing or ablation of C4 da neurons largely eliminates larval responses to noxious stimuli [10-12], whereas optogenetic activation of C4 da neurons is sufficient to provoke corkscrew-like rolling behavior similar to what is observed when larvae receive noxious stimuli, such as high temperature or harsh mechanical stimulation [10-12]. The receptors and the regulatory mechanisms for C4 da activation in response to a variety of noxious stimuli have been well studied [13-23], yet how C4 da activation triggers the escape behavior in the circuit level is still incompletely understood. Here we identify segmentally arrayed local interneurons (medial clusters of C4 da second-order interneurons [mCSIs]) in the ventral nerve cord that are necessary and sufficient to trigger rolling behavior. GFP reconstitution across synaptic partners (GRASP) analysis indicates that C4 da axons form synapses with mCSI dendrites. Optogenetic activation of mCSIs induces the rolling behavior, whereas silencing mCSIs reduces the probability of rolling behavior upon C4 da activation. Further anatomical and functional studies suggest that the C4 da-mCSI nociceptive circuit evokes rolling behavior at least in part through segmental nerve a (SNa) motor neurons. Our findings thus uncover a local circuit that promotes escape behavior upon noxious stimuli in Drosophila larvae and provide mechanistic insights into how noxious stimuli are transduced into the stereotyped escape behavior in the circuit level.
Collapse
Affiliation(s)
- Jiro Yoshino
- Department of Biological Sciences, School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Rei K Morikawa
- Department of Biological Sciences, School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Eri Hasegawa
- Department of Biological Sciences, School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Kazuo Emoto
- Department of Biological Sciences, School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
| |
Collapse
|
46
|
Thompson-Peer KL, DeVault L, Li T, Jan LY, Jan YN. In vivo dendrite regeneration after injury is different from dendrite development. Genes Dev 2017; 30:1776-89. [PMID: 27542831 PMCID: PMC5002981 DOI: 10.1101/gad.282848.116] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 07/25/2016] [Indexed: 12/22/2022]
Abstract
Thompson-Peer et al. show that, in intact Drosophila larvae, a discrete injury that removes all dendrites induces robust dendritic growth that recreates many features of uninjured dendrites. However, the growth and patterning of injury-induced dendrites is significantly different from uninjured dendrites. Neurons receive information along dendrites and send signals along axons to synaptic contacts. The factors that control axon regeneration have been examined in many systems, but dendrite regeneration has been largely unexplored. Here we report that, in intact Drosophila larvae, a discrete injury that removes all dendrites induces robust dendritic growth that recreates many features of uninjured dendrites, including the number of dendrite branches that regenerate and responsiveness to sensory stimuli. However, the growth and patterning of injury-induced dendrites is significantly different from uninjured dendrites. We found that regenerated arbors cover much less territory than uninjured neurons, fail to avoid crossing over other branches from the same neuron, respond less strongly to mechanical stimuli, and are pruned precociously. Finally, silencing the electrical activity of the neurons specifically blocks injury-induced, but not developmental, dendrite growth. By elucidating the essential features of dendrites grown in response to acute injury, our work builds a framework for exploring dendrite regeneration in physiological and pathological conditions.
Collapse
Affiliation(s)
- Katherine L Thompson-Peer
- Howard Hughes Medical Institute, Department of Physiology, Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, California 94158, USA
| | - Laura DeVault
- Howard Hughes Medical Institute, Department of Physiology, Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, California 94158, USA
| | - Tun Li
- Howard Hughes Medical Institute, Department of Physiology, Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, California 94158, USA
| | - Lily Yeh Jan
- Howard Hughes Medical Institute, Department of Physiology, Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, California 94158, USA
| | - Yuh Nung Jan
- Howard Hughes Medical Institute, Department of Physiology, Department of Biochemistry and Biophysics, University of California at San Francisco, San Francisco, California 94158, USA
| |
Collapse
|
47
|
Patel AA, Cox DN. Behavioral and Functional Assays for Investigating Mechanisms of Noxious Cold Detection and Multimodal Sensory Processing in Drosophila Larvae. Bio Protoc 2017; 7:e2388. [PMID: 28835907 DOI: 10.21769/bioprotoc.2388] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
To investigate cellular, molecular and behavioral mechanisms of noxious cold detection, we developed cold plate behavioral assays and quantitative means for evaluating the predominant noxious cold-evoked contraction behavior. To characterize neural activity in response to noxious cold, we implemented a GCaMP6-based calcium imaging assay enabling in vivo studies of intracellular calcium dynamics in intact Drosophila larvae. We identified Drosophila class III multidendritic (md) sensory neurons as multimodal sensors of innocuous mechanical and noxious cold stimuli and to dissect the mechanistic bases of multimodal sensory processing we developed two independent functional assays. First, we developed an optogenetic dose response assay to assess whether levels of neural activation contributes to the multimodal aspects of cold sensitive sensory neurons. Second, we utilized CaMPARI, a photo-switchable calcium integrator that stably converts fluorescence from green to red in presence of high intracellular calcium and photo-converting light, to assess in vivo functional differences in neural activation levels between innocuous mechanical and noxious cold stimuli. These novel assays enable investigations of behavioral and functional roles of peripheral sensory neurons and multimodal sensory processing in Drosophila larvae.
Collapse
Affiliation(s)
- Atit A Patel
- Neuroscience Institute, Georgia State University, Atlanta, GA, USA
| | - Daniel N Cox
- Neuroscience Institute, Georgia State University, Atlanta, GA, USA
| |
Collapse
|
48
|
Watanabe K, Furumizo Y, Usui T, Hattori Y, Uemura T. Nutrient-dependent increased dendritic arborization of somatosensory neurons. Genes Cells 2016; 22:105-114. [DOI: 10.1111/gtc.12451] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 10/19/2016] [Indexed: 12/21/2022]
Affiliation(s)
- Kaori Watanabe
- Graduate School of Biostudies; Kyoto University; Kyoto 606-8501 Japan
| | - Yuki Furumizo
- Graduate School of Biostudies; Kyoto University; Kyoto 606-8501 Japan
| | - Tadao Usui
- Graduate School of Biostudies; Kyoto University; Kyoto 606-8501 Japan
| | - Yukako Hattori
- Graduate School of Biostudies; Kyoto University; Kyoto 606-8501 Japan
| | - Tadashi Uemura
- Graduate School of Biostudies; Kyoto University; Kyoto 606-8501 Japan
| |
Collapse
|
49
|
Katta S, Krieg M, Goodman MB. Feeling force: physical and physiological principles enabling sensory mechanotransduction. Annu Rev Cell Dev Biol 2016; 31:347-71. [PMID: 26566115 DOI: 10.1146/annurev-cellbio-100913-013426] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Organisms as diverse as microbes, roundworms, insects, and mammals detect and respond to applied force. In animals, this ability depends on ionotropic force receptors, known as mechanoelectrical transduction (MeT) channels, that are expressed by specialized mechanoreceptor cells embedded in diverse tissues and distributed throughout the body. These cells mediate hearing, touch, and proprioception and play a crucial role in regulating organ function. Here, we attempt to integrate knowledge about the architecture of mechanoreceptor cells and their sensory organs with principles of cell mechanics, and we consider how engulfing tissues contribute to mechanical filtering. We address progress in the quest to identify the proteins that form MeT channels and to understand how these channels are gated. For clarity and convenience, we focus on sensory mechanobiology in nematodes, fruit flies, and mice. These themes are emphasized: asymmetric responses to applied forces, which may reflect anisotropy of the structure and mechanics of sensory mechanoreceptor cells, and proteins that function as MeT channels, which appear to have emerged many times through evolution.
Collapse
Affiliation(s)
- Samata Katta
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, California 94305;
| | - Michael Krieg
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, California 94305;
| | - Miriam B Goodman
- Department of Molecular and Cellular Physiology, Stanford University, Stanford, California 94305;
| |
Collapse
|
50
|
Role of kinesin-1-based microtubule sliding in Drosophila nervous system development. Proc Natl Acad Sci U S A 2016; 113:E4985-94. [PMID: 27512046 DOI: 10.1073/pnas.1522416113] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The plus-end microtubule (MT) motor kinesin-1 is essential for normal development, with key roles in the nervous system. Kinesin-1 drives axonal transport of membrane cargoes to fulfill the metabolic needs of neurons and maintain synapses. We have previously demonstrated that kinesin-1, in addition to its well-established role in organelle transport, can drive MT-MT sliding by transporting "cargo" MTs along "track" MTs, resulting in dramatic cell shape changes. The mechanism and physiological relevance of this MT sliding are unclear. In addition to its motor domain, kinesin-1 contains a second MT-binding site, located at the C terminus of the heavy chain. Here, we mutated this C-terminal MT-binding site such that the ability of kinesin-1 to slide MTs is significantly compromised, whereas cargo transport is unaffected. We introduced this mutation into the genomic locus of kinesin-1 heavy chain (KHC), generating the Khc(mutA) allele. Khc(mutA) neurons displayed significant MT sliding defects while maintaining normal transport of many cargoes. Using this mutant, we demonstrated that MT sliding is required for axon and dendrite outgrowth in vivo. Consistent with these results, Khc(mutA) flies displayed severe locomotion and viability defects. To test the role of MT sliding further, we engineered a chimeric motor that actively slides MTs but cannot transport organelles. Activation of MT sliding in Khc(mutA) neurons using this chimeric motor rescued axon outgrowth in cultured neurons and in vivo, firmly establishing the role of sliding in axon outgrowth. These results demonstrate that MT sliding by kinesin-1 is an essential biological phenomenon required for neuronal morphogenesis and normal nervous system development.
Collapse
|