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Dolezal DM, Joiner MLA, Eberl DF. Two distinct functions of Lim1 in the Drosophila antenna. MICROPUBLICATION BIOLOGY 2024; 2024:10.17912/micropub.biology.001229. [PMID: 38957438 PMCID: PMC11217802 DOI: 10.17912/micropub.biology.001229] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Revised: 06/14/2024] [Accepted: 06/14/2024] [Indexed: 07/04/2024]
Abstract
The Lim1 transcription factor is required in Drosophila for patterning the eye-antennal disk. At the adult stage, Lim1 is strongly expressed in Johnston's Organ (JO) neurons, the antennal auditory organ. Using RNAi-mediated knockdown of Lim1 using a strong neuronal driver, we find a significant reduction in electrophysiological responses to auditory stimuli, recorded from the antennal nerve. This reduction can be accounted for by Lim1 knockdown in the auditory subset of JO neurons, with no effect of knockdown in JO neuron subsets associated with wind or gravity detection. Conversely, Lim1 knockdown in JO sense organ precursors had no effect on hearing. Mosaic animals with antennal clones of the Lim1 E9 null mutation showed morphological defects in the antenna, and significant auditory electrophysiological defects. Our results are consistent with two distinct functions for Lim1 in the antenna, including an early patterning function in the eye-antennal disk, and a later neural differentiation function in the JO neurons.
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Affiliation(s)
| | | | - Daniel F Eberl
- Biology, University of Iowa, Iowa City, Iowa, United States
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2
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Sutton DC, Andrews JC, Dolezal DM, Park YJ, Li H, Eberl DF, Yamamoto S, Groves AK. Comparative exploration of mammalian deafness gene homologues in the Drosophila auditory organ shows genetic correlation between insect and vertebrate hearing. PLoS One 2024; 19:e0297846. [PMID: 38412189 PMCID: PMC10898740 DOI: 10.1371/journal.pone.0297846] [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: 07/21/2023] [Accepted: 01/13/2024] [Indexed: 02/29/2024] Open
Abstract
Johnston's organ, the Drosophila auditory organ, is anatomically very different from the mammalian organ of Corti. However, recent evidence indicates significant cellular and molecular similarities exist between vertebrate and invertebrate hearing, suggesting that Drosophila may be a useful platform to determine the function of the many mammalian deafness genes whose underlying biological mechanisms are poorly characterized. Our goal was a comprehensive screen of all known orthologues of mammalian deafness genes in the fruit fly to better understand conservation of hearing mechanisms between the insect and the fly and ultimately gain insight into human hereditary deafness. We used bioinformatic comparisons to screen previously reported human and mouse deafness genes and found that 156 of them have orthologues in Drosophila melanogaster. We used fluorescent imaging of T2A-GAL4 gene trap and GFP or YFP fluorescent protein trap lines for 54 of the Drosophila genes and found 38 to be expressed in different cell types in Johnston's organ. We phenotypically characterized the function of strong loss-of-function mutants in three genes expressed in Johnston's organ (Cad99C, Msp-300, and Koi) using a courtship assay and electrophysiological recordings of sound-evoked potentials. Cad99C and Koi were found to have significant courtship defects. However, when we tested these genes for electrophysiological defects in hearing response, we did not see a significant difference suggesting the courtship defects were not caused by hearing deficiencies. Furthermore, we used a UAS/RNAi approach to test the function of seven genes and found two additional genes, CG5921 and Myo10a, that gave a statistically significant delay in courtship but not in sound-evoked potentials. Our results suggest that many mammalian deafness genes have Drosophila homologues expressed in the Johnston's organ, but that their requirement for hearing may not necessarily be the same as in mammals.
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Affiliation(s)
- Daniel C. Sutton
- Graduate Program in Genetics & Genomics, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
| | - Jonathan C. Andrews
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, Texas, United States of America
| | - Dylan M. Dolezal
- Department of Biology, University of Iowa, Iowa City, Iowa, United States of America
| | - Ye Jin Park
- Graduate Program in Development, Disease Models & Therapeutics, Baylor College of Medicine, Houston, Texas, United States of America
- Huffington Center on Aging, One Baylor Plaza, Houston, Texas, United States of America
| | - Hongjie Li
- Graduate Program in Development, Disease Models & Therapeutics, Baylor College of Medicine, Houston, Texas, United States of America
- Huffington Center on Aging, One Baylor Plaza, Houston, Texas, United States of America
| | - Daniel F. Eberl
- Department of Biology, University of Iowa, Iowa City, Iowa, United States of America
| | - Shinya Yamamoto
- Graduate Program in Genetics & Genomics, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Houston, Texas, United States of America
- Graduate Program in Development, Disease Models & Therapeutics, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, United States of America
| | - Andrew K. Groves
- Graduate Program in Genetics & Genomics, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, United States of America
- Graduate Program in Development, Disease Models & Therapeutics, Baylor College of Medicine, Houston, Texas, United States of America
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, United States of America
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3
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Zhang B, Duan H, Kavaler J, Wei L, Eberl DF, Lai EC. A nonneural miRNA cluster mediates hearing via repression of two neural targets. Genes Dev 2023; 37:1041-1051. [PMID: 38110249 PMCID: PMC10760640 DOI: 10.1101/gad.351052.123] [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: 08/07/2023] [Accepted: 11/29/2023] [Indexed: 12/20/2023]
Abstract
We show here that mir-279/996 are absolutely essential for development and function of Johnston's organ (JO), the primary proprioceptive and auditory organ in Drosophila Their deletion results in highly aberrant cell fate determination, including loss of scolopale cells and ectopic neurons, and mutants are electrophysiologically deaf. In vivo activity sensors and mosaic analyses indicate that these seed-related miRNAs function autonomously to suppress neural fate in nonneuronal cells. Finally, genetic interactions pinpoint two neural targets (elav and insensible) that underlie miRNA mutant JO phenotypes. This work uncovers how critical post-transcriptional regulation of specific miRNA targets governs cell specification and function of the auditory system.
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Affiliation(s)
- Binglong Zhang
- Developmental Biology Program, Sloan Kettering Institute, New York, New York 10065, USA
| | - Hong Duan
- Developmental Biology Program, Sloan Kettering Institute, New York, New York 10065, USA
| | - Joshua Kavaler
- Department of Biology, Colby College, Waterville, Maine 04901, USA
| | - Lu Wei
- Developmental Biology Program, Sloan Kettering Institute, New York, New York 10065, USA
| | - Daniel F Eberl
- Department of Biology, University of Iowa, Iowa City, Iowa 52242, USA
| | - Eric C Lai
- Developmental Biology Program, Sloan Kettering Institute, New York, New York 10065, USA;
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4
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Ishida IG, Sethi S, Mohren TL, Abbott L, Maimon G. Neuronal calcium spikes enable vector inversion in the Drosophila brain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.24.568537. [PMID: 38077032 PMCID: PMC10705278 DOI: 10.1101/2023.11.24.568537] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
A typical neuron signals to downstream cells when it is depolarized and firing sodium spikes. Some neurons, however, also fire calcium spikes when hyperpolarized. The function of such bidirectional signaling remains unclear in most circuits. Here we show how a neuron class that participates in vector computation in the fly central complex employs hyperpolarization-elicited calcium spikes to invert two-dimensional mathematical vectors. When cells switch from firing sodium to calcium spikes, this leads to a ~180° realignment between the vector encoded in the neuronal population and the fly's internal heading signal, thus inverting the vector. We show that the calcium spikes rely on the T-type calcium channel Ca-α1T, and argue, via analytical and experimental approaches, that these spikes enable vector computations in portions of angular space that would otherwise be inaccessible. These results reveal a seamless interaction between molecular, cellular and circuit properties for implementing vector math in the brain.
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Affiliation(s)
- Itzel G. Ishida
- Laboratory of Integrative Brain Function and Howard Hughes Medical Institute, The Rockefeller University, New York NY, USA
| | - Sachin Sethi
- Laboratory of Integrative Brain Function and Howard Hughes Medical Institute, The Rockefeller University, New York NY, USA
| | - Thomas L. Mohren
- Laboratory of Integrative Brain Function and Howard Hughes Medical Institute, The Rockefeller University, New York NY, USA
| | - L.F. Abbott
- Mortimer B. Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York NY, USA
| | - Gaby Maimon
- Laboratory of Integrative Brain Function and Howard Hughes Medical Institute, The Rockefeller University, New York NY, USA
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5
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Sharma Y, Jacobs JS, Sivan-Loukianova E, Lee E, Kernan MJ, Eberl DF. The retrograde IFT dynein is required for normal function of diverse mechanosensory cilia in Drosophila. Front Mol Neurosci 2023; 16:1263411. [PMID: 37808471 PMCID: PMC10556659 DOI: 10.3389/fnmol.2023.1263411] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Accepted: 09/07/2023] [Indexed: 10/10/2023] Open
Abstract
Introduction Cilia biogenesis relies on intraflagellar transport (IFT), a conserved transport mechanism which functions bi-directionally to bring protein complexes to the growing ciliary tip and recycle signaling and transport proteins between the cilium and cell body. In Drosophila, anterograde IFT is critical for assembly of sensory cilia in the neurons of both chordotonal (ch) organs, which have relatively long ciliary axonemes, and external sensory (es) organs, which have short axonemal segments with microtubules in distal sensory segments forming non-axonemal bundles. We previously isolated the beethoven (btv) mutant in a mutagenesis screen for auditory mutants. Although many btv mutant flies are deaf, some retain a small residual auditory function as determined both by behavior and by auditory electrophysiology. Results Here we molecularly characterize the btv gene and demonstrate that it encodes the IFT-associated dynein-2 heavy chain Dync2h1. We also describe morphological changes in Johnston's organ as flies age to 30 days, and we find that morphological and electrophysiological phenotypes in this ch organ of btv mutants become more severe with age. We show that NompB protein, encoding the conserved IFT88 protein, an IFT complex B component, fails to be cleared from chordotonal cilia in btv mutants, instead accumulating in the distorted cilia. In macrochaete bristles, a class of es organ, btv mutants show a 50% reduction in mechanoreceptor potentials. Discussion Thus, the btv-encoded Dync2h1 functions as the retrograde IFT motor in the assembly of long ciliary axonemes in ch organs and is also important for normal function of the short ciliary axonemes in es organs.
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Affiliation(s)
- Yashoda Sharma
- Department of Biology, The University of Iowa, Iowa City, IA, United States
| | - Julie S. Jacobs
- Department of Biology, The University of Iowa, Iowa City, IA, United States
| | | | - Eugene Lee
- Department of Neurobiology and Behavior, State University of New York, Stony Brook, NY, United States
| | - Maurice J. Kernan
- Department of Neurobiology and Behavior, State University of New York, Stony Brook, NY, United States
| | - Daniel F. Eberl
- Department of Biology, The University of Iowa, Iowa City, IA, United States
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6
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Yamanouchi HM, Tanaka R, Kamikouchi A. Piezo-mediated mechanosensation contributes to stabilizing copulation posture and reproductive success in Drosophila males. iScience 2023; 26:106617. [PMID: 37250311 PMCID: PMC10214400 DOI: 10.1016/j.isci.2023.106617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 03/13/2023] [Accepted: 04/04/2023] [Indexed: 05/31/2023] Open
Abstract
In internal fertilization animals, reproductive success depends on maintaining copulation until gametes are transported from male to female. In Drosophila melanogaster, mechanosensation in males likely contributes to copulation maintenance, but its molecular underpinning remains to be identified. Here we show that the mechanosensory gene piezo and its' expressing neurons are responsible for copulation maintenance. An RNA-seq database search and subsequent mutant analysis revealed the importance of piezo for maintaining male copulation posture. piezo-GAL4-positive signals were found in the sensory neurons of male genitalia bristles, and optogenetic inhibition of piezo-expressing neurons in the posterior side of the male body during copulation destabilized posture and terminated copulation. Our findings suggest that the mechanosensory system of male genitalia through Piezo channels plays a key role in copulation maintenance and indicate that Piezo may increase male fitness during copulation in flies.
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Affiliation(s)
| | - Ryoya Tanaka
- Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602, Japan
| | - Azusa Kamikouchi
- Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602, Japan
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Nagoya, Aichi 464-8602, Japan
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7
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Spalthoff C, Salgado VL, Balu N, David MD, Hehlert P, Huang H, Jones JE, Kandasamy R, Knudsen GA, Lelito KR, Machamer JB, Nesterov A, Tomalski M, Wahl GD, Wedel BJ, Göpfert MC. The novel pyridazine pyrazolecarboxamide insecticide dimpropyridaz inhibits chordotonal organ function upstream of TRPV channels. PEST MANAGEMENT SCIENCE 2023; 79:1635-1649. [PMID: 36622360 DOI: 10.1002/ps.7352] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 12/19/2022] [Accepted: 01/09/2023] [Indexed: 06/17/2023]
Abstract
BACKGROUND Pyridazine pyrazolecarboxamides (PPCs) are a novel insecticide class discovered and optimized at BASF. Dimpropyridaz is the first PPC to be submitted for registration and controls many aphid species as well as whiteflies and other piercing-sucking insects. RESULTS Dimpropyridaz and other tertiary amide PPCs are proinsecticides that are converted in vivo into secondary amide active forms by N-dealkylation. Active secondary amide metabolites of PPCs potently inhibit the function of insect chordotonal neurons. Unlike Group 9 and 29 insecticides, which hyperactivate chordotonal neurons and increase Ca2+ levels, active metabolites of PPCs silence chordotonal neurons and decrease intracellular Ca2+ levels. Whereas the effects of Group 9 and 29 insecticides require TRPV (Transient Receptor Potential Vanilloid) channels, PPCs act in a TRPV-independent fashion, without compromising cellular responses to Group 9 and 29 insecticides, placing the molecular PPC target upstream of TRPVs. CONCLUSIONS PPCs are a new class of chordotonal organ modulator insecticide for control of piercing-sucking pests. Dimpropyridaz is a PPC proinsecticide that is activated in target insects to secondary amide forms that inhibit the firing of chordotonal organs. The inhibition occurs at a site upstream of TRPVs and is TRPV-independent, providing a novel mode of action for resistance management. © 2023 BASF Corporation. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Christian Spalthoff
- Department of Cellular Neurobiology, University of Göttingen, Göttingen, Germany
| | | | | | | | - Philip Hehlert
- Department of Cellular Neurobiology, University of Göttingen, Göttingen, Germany
| | | | | | | | | | | | | | | | | | | | | | - Martin C Göpfert
- Department of Cellular Neurobiology, University of Göttingen, Göttingen, Germany
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8
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Ohashi TS, Ishikawa Y, Awasaki T, Su MP, Yoneyama Y, Morimoto N, Kamikouchi A. Evolutionary conservation and diversification of auditory neural circuits that process courtship songs in Drosophila. Sci Rep 2023; 13:383. [PMID: 36611081 PMCID: PMC9825394 DOI: 10.1038/s41598-022-27349-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Accepted: 12/30/2022] [Indexed: 01/09/2023] Open
Abstract
Acoustic communication signals diversify even on short evolutionary time scales. To understand how the auditory system underlying acoustic communication could evolve, we conducted a systematic comparison of the early stages of the auditory neural circuit involved in song information processing between closely-related fruit-fly species. Male Drosophila melanogaster and D. simulans produce different sound signals during mating rituals, known as courtship songs. Female flies from these species selectively increase their receptivity when they hear songs with conspecific temporal patterns. Here, we firstly confirmed interspecific differences in temporal pattern preferences; D. simulans preferred pulse songs with longer intervals than D. melanogaster. Primary and secondary song-relay neurons, JO neurons and AMMC-B1 neurons, shared similar morphology and neurotransmitters between species. The temporal pattern preferences of AMMC-B1 neurons were also relatively similar between species, with slight but significant differences in their band-pass properties. Although the shift direction of the response property matched that of the behavior, these differences are not large enough to explain behavioral differences in song preferences. This study enhances our understanding of the conservation and diversification of the architecture of the early-stage neural circuit which processes acoustic communication signals.
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Affiliation(s)
- Takuro S. Ohashi
- grid.27476.300000 0001 0943 978XGraduate School of Science, Nagoya University, Nagoya, Aichi 464-8602 Japan
| | - Yuki Ishikawa
- Graduate School of Science, Nagoya University, Nagoya, Aichi, 464-8602, Japan.
| | - Takeshi Awasaki
- grid.411205.30000 0000 9340 2869School of Medicine, Kyorin University, Tokyo, 181-8611 Japan
| | - Matthew P. Su
- grid.27476.300000 0001 0943 978XGraduate School of Science, Nagoya University, Nagoya, Aichi 464-8602 Japan ,grid.27476.300000 0001 0943 978XInstitute for Advanced Research, Nagoya University, Nagoya, Aichi 464-8601 Japan
| | - Yusuke Yoneyama
- grid.27476.300000 0001 0943 978XGraduate School of Science, Nagoya University, Nagoya, Aichi 464-8602 Japan
| | - Nao Morimoto
- grid.39158.360000 0001 2173 7691Institute for Genetic Medicine, Hokkaido University, Sapporo, Hokkaido 060-0815 Japan
| | - Azusa Kamikouchi
- Graduate School of Science, Nagoya University, Nagoya, Aichi, 464-8602, Japan. .,Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, 980-8577, Japan.
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9
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Almazán A, Çevrim Ç, Musser JM, Averof M, Paris M. Crustacean leg regeneration restores complex microanatomy and cell diversity. SCIENCE ADVANCES 2022; 8:eabn9823. [PMID: 36001670 PMCID: PMC9401613 DOI: 10.1126/sciadv.abn9823] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2022] [Accepted: 07/11/2022] [Indexed: 06/15/2023]
Abstract
Animals can regenerate complex organs, yet this process frequently results in imprecise replicas of the original structure. In the crustacean Parhyale, embryonic and regenerating legs differ in gene expression dynamics but produce apparently similar mature structures. We examine the fidelity of Parhyale leg regeneration using complementary approaches to investigate microanatomy, sensory function, cellular composition, and cell molecular profiles. We find that regeneration precisely replicates the complex microanatomy and spatial distribution of external sensory organs and restores their sensory function. Single-nuclei sequencing shows that regenerated and uninjured legs are indistinguishable in terms of cell-type composition and transcriptional profiles. This remarkable fidelity highlights the ability of organisms to achieve identical outcomes via distinct processes.
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Affiliation(s)
- Alba Almazán
- Institut de Génomique Fonctionnelle de Lyon (IGFL), Centre National de la Recherche Scientifique (CNRS), École Normale Supérieure de Lyon and Université Claude Bernard Lyon 1, 69007 Lyon, France
| | - Çağrı Çevrim
- Institut de Génomique Fonctionnelle de Lyon (IGFL), Centre National de la Recherche Scientifique (CNRS), École Normale Supérieure de Lyon and Université Claude Bernard Lyon 1, 69007 Lyon, France
| | - Jacob M. Musser
- European Molecular Biology Laboratory, Developmental Biology Unit, Meyerhofstrasse 1, Heidelberg 69117, Germany
| | - Michalis Averof
- Institut de Génomique Fonctionnelle de Lyon (IGFL), Centre National de la Recherche Scientifique (CNRS), École Normale Supérieure de Lyon and Université Claude Bernard Lyon 1, 69007 Lyon, France
| | - Mathilde Paris
- Institut de Génomique Fonctionnelle de Lyon (IGFL), Centre National de la Recherche Scientifique (CNRS), École Normale Supérieure de Lyon and Université Claude Bernard Lyon 1, 69007 Lyon, France
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10
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Xiang W, Zur Lage P, Newton FG, Qiu G, Jarman AP. The dynamics of protein localisation to restricted zones within Drosophila mechanosensory cilia. Sci Rep 2022; 12:13338. [PMID: 35922464 PMCID: PMC9349282 DOI: 10.1038/s41598-022-17189-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 07/21/2022] [Indexed: 12/02/2022] Open
Abstract
The Drosophila chordotonal neuron cilium is the site of mechanosensory transduction. The cilium has a 9 + 0 axoneme structure and is highly sub-compartmentalised, with proximal and distal zones harbouring different TRP channels and the proximal zone axoneme also being decorated with axonemal dynein motor complexes. The activity of the dynein complexes is essential for mechanotransduction. We investigate the localisation of TRP channels and dynein motor complexes during ciliogenesis. Differences in timing of TRP channel localisation correlate with order of construction of the two ciliary zones. Dynein motor complexes are initially not confined to their target proximal zone, but ectopic complexes beyond the proximal zone are later cleared, perhaps by retrograde transport. Differences in transient distal localisation of outer and inner dynein arm complexes (ODAs and IDAs) are consistent with previous suggestions from unicellular eukaryotes of differences in processivity during intraflagellar transport. Stable localisation depends on the targeting of their docking proteins in the proximal zone. For ODA, we characterise an ODA docking complex (ODA-DC) that is targeted directly to the proximal zone. Interestingly, the subunit composition of the ODA-DC in chordotonal neuron cilia appears to be different from the predicted ODA-DC in Drosophila sperm.
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Affiliation(s)
- Wangchu Xiang
- Centre for Discovery Brain Sciences, Edinburgh Medical School, University of Edinburgh, Edinburgh, EH8 9XD, UK.,Department of Neurobiology, Harvard Medical School, Boston, MA, 02215, USA
| | - Petra Zur Lage
- Centre for Discovery Brain Sciences, Edinburgh Medical School, University of Edinburgh, Edinburgh, EH8 9XD, UK
| | - Fay G Newton
- Centre for Discovery Brain Sciences, Edinburgh Medical School, University of Edinburgh, Edinburgh, EH8 9XD, UK.,Institute of Genetics and Cancer, University of Edinburgh, Edinburgh, EH4 2XU, UK
| | - Guiyun Qiu
- Centre for Discovery Brain Sciences, Edinburgh Medical School, University of Edinburgh, Edinburgh, EH8 9XD, UK.,Centre for Regenerative Medicine, Institute for Regeneration and Repair, University of Edinburgh, Edinburgh BioQuarter, 5 Little France Drive, Edinburgh, EH16 4UU, UK
| | - Andrew P Jarman
- Centre for Discovery Brain Sciences, Edinburgh Medical School, University of Edinburgh, Edinburgh, EH8 9XD, UK.
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11
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Nanchung and Inactive define pore properties of the native auditory transduction channel in Drosophila. Proc Natl Acad Sci U S A 2021; 118:2106459118. [PMID: 34848538 DOI: 10.1073/pnas.2106459118] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/17/2021] [Indexed: 11/18/2022] Open
Abstract
Auditory transduction is mediated by chordotonal (Cho) neurons in Drosophila larvae, but the molecular identity of the mechanotransduction (MET) channel is elusive. Here, we established a whole-cell recording system of Cho neurons and showed that two transient receptor potential vanilloid (TRPV) channels, Nanchung (NAN) and Inactive (IAV), are essential for MET currents in Cho neurons. NAN and IAV form active ion channels when expressed simultaneously in S2 cells. Point mutations in the pore region of NAN-IAV change the reversal potential of the MET currents. Particularly, residues 857 through 990 in the IAV carboxyl terminus regulate the kinetics of MET currents in Cho neurons. In addition, TRPN channel NompC contributes to the adaptation of auditory transduction currents independent of its ion-conduction function. These results indicate that NAN-IAV, rather than NompC, functions as essential pore-forming subunits of the native auditory transduction channel in Drosophila and provide insights into the gating mechanism of MET currents in Cho neurons.
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12
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Abstract
Hypersynchronous neural activity is a characteristic feature of seizures. Although many Drosophila mutants of epilepsy-related genes display clear behavioral spasms and motor unit hyperexcitability, field potential measurements of aberrant hypersynchronous activity across brain regions during seizures have yet to be described. Here, we report a straightforward method to observe local field potentials (LFPs) from the Drosophila brain to monitor ensemble neural activity during seizures in behaving tethered flies. High frequency stimulation across the brain reliably triggers a stereotypic sequence of electroconvulsive seizure (ECS) spike discharges readily detectable in the dorsal longitudinal muscle (DLM) and coupled with behavioral spasms. During seizure episodes, the LFP signal displayed characteristic large-amplitude oscillations with a stereotypic temporal correlation to DLM flight muscle spiking. ECS-related LFP events were clearly distinct from rest- and flight-associated LFP patterns. We further characterized the LFP activity during different types of seizures originating from genetic and pharmacological manipulations. In the 'bang-sensitive' sodium channel mutant bangsenseless (bss), the LFP pattern was prolonged, and the temporal correlation between LFP oscillations and DLM discharges was altered. Following administration of the pro-convulsant GABAA blocker picrotoxin, we uncovered a qualitatively different LFP activity pattern, which consisted of a slow (1-Hz), repetitive, waveform, closely coupled with DLM bursting and behavioral spasms. Our approach to record brain LFPs presents an initial framework for electrophysiological analysis of the complex brain-wide activity patterns in the large collection of Drosophila excitability mutants.
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Affiliation(s)
- Atulya Iyengar
- Department of Biology, and Iowa Neuroscience Institute, University of Iowa, Iowa City, IA, USA
| | - Chun-Fang Wu
- Department of Biology, and Iowa Neuroscience Institute, University of Iowa, Iowa City, IA, USA
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13
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Hodge SH, Watts A, Marley R, Baines RA, Hafen E, MacDougall LK. Twitchy, the Drosophila orthologue of the ciliary gating protein FBF1/dyf-19, is required for coordinated locomotion and male fertility. Biol Open 2021; 10:bio058531. [PMID: 34357392 PMCID: PMC8353261 DOI: 10.1242/bio.058531] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 06/21/2021] [Indexed: 12/13/2022] Open
Abstract
Primary cilia are compartmentalised from the rest of the cell by a ciliary gate comprising transition fibres and a transition zone. The ciliary gate allows the selective import and export of molecules such as transmembrane receptors and transport proteins. These are required for the assembly of the cilium, its function as a sensory and signalling centre and to maintain its distinctive composition. Certain motile cilia can also form within the cytosol as exemplified by human and Drosophila sperm. The role of transition fibre proteins has not been well described in the cytoplasmic cilia. Drosophila have both compartmentalised primary cilia, in sensory neurons, and sperm flagella that form within the cytosol. Here, we describe phenotypes for twitchy the Drosophila orthologue of a transition fibre protein, mammalian FBF1/C. elegans dyf-19. Loss-of-function mutants in twitchy are adult lethal and display a severely uncoordinated phenotype. Twitchy flies are too uncoordinated to mate but RNAi-mediated loss of twitchy specifically within the male germline results in coordinated but infertile adults. Examination of sperm from twitchy RNAi-knockdown flies shows that the flagellar axoneme forms, elongates and is post-translationally modified by polyglycylation but the production of motile sperm is impaired. These results indicate that twitchy is required for the function of both sensory cilia that are compartmentalised from the rest of the cell and sperm flagella that are formed within the cytosol of the cell. Twitchy is therefore likely to function as part of a molecular gate in sensory neurons but may have a distinct function in sperm cells.
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Affiliation(s)
- Suzanne H. Hodge
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, UK
| | - Amy Watts
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, UK
| | - Richard Marley
- 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 9PL, UK
| | - 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 9PL, UK
| | - Ernst Hafen
- Institute of Molecular Systems Biology, Swiss Federal Institute of Technology (ETH) Zürich, 8093, Zürich, Switzerland
| | - Lindsay K. MacDougall
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester M13 9PT, UK
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14
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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: 46] [Impact Index Per Article: 15.3] [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.
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Affiliation(s)
- Craig Montell
- Department of Molecular, Cellular, and Developmental Biology, The Neuroscience Research Institute, University of California, Santa Barbara, CA 93106, USA
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15
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Li B, Li S, Yan Z. Axonemal Dynein DNAH5 is Required for Sound Sensation in Drosophila Larvae. Neurosci Bull 2021; 37:523-534. [PMID: 33570705 DOI: 10.1007/s12264-021-00631-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2020] [Accepted: 05/09/2020] [Indexed: 11/29/2022] Open
Abstract
Chordotonal neurons are responsible for sound sensation in Drosophila. However, little is known about how they respond to sound with high sensitivity. Using genetic labeling, we found one of the Drosophila axonemal dynein heavy chains, CG9492 (DNAH5), was specifically expressed in larval chordotonal neurons and showed a distribution restricted to proximal cilia. While DNAH5 mutation did not affect the cilium morphology or the trafficking of Inactive, a candidate auditory transduction channel, larvae with DNAH5 mutation had reduced startle responses to sound at low and medium intensities. Calcium imaging confirmed that DNAH5 functioned autonomously in chordotonal neurons for larval sound sensation. Furthermore, disrupting DNAH5 resulted in a decrease of spike firing responses to low-level sound in chordotonal neurons. Intriguingly, DNAH5 mutant larvae displayed an altered frequency tuning curve of the auditory organs. All together, our findings support a critical role of DNAH5 in tuning the frequency selectivity and the sound sensitivity of larval auditory neurons.
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Affiliation(s)
- Bingxue Li
- State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science, Department of Physiology and Biophysics, Institute of Brain Science, School of Life Sciences, Fudan University, Shanghai, 200438, China
- Institute of Molecular Physiology, Shenzhen Bay Laboratory, Shenzhen, 518132, China
| | - Songling Li
- State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science, Department of Physiology and Biophysics, Institute of Brain Science, School of Life Sciences, Fudan University, Shanghai, 200438, China
- Institute of Molecular Physiology, Shenzhen Bay Laboratory, Shenzhen, 518132, China
| | - Zhiqiang Yan
- State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science, Department of Physiology and Biophysics, Institute of Brain Science, School of Life Sciences, Fudan University, Shanghai, 200438, China.
- Institute of Molecular Physiology, Shenzhen Bay Laboratory, Shenzhen, 518132, China.
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16
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Kwon Y, Lee J, Chung YD. Sub-Ciliary Segregation of Two Drosophila Transient Receptor Potential Channels Begins at the Initial Stage of Their Pre-Ciliary Trafficking. Mol Cells 2020; 43:1002-1010. [PMID: 33323559 PMCID: PMC7772507 DOI: 10.14348/molcells.2020.0205] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2020] [Revised: 11/15/2020] [Accepted: 11/15/2020] [Indexed: 12/14/2022] Open
Abstract
Cilia are important eukaryotic cellular compartments required for diverse biological functions. Recent studies have revealed that protein targeting into the proper ciliary subcompartments is essential for ciliary function. In Drosophila chordotonal cilium, where mechano-electric transduction occurs, two transient receptor potential (TRP) superfamily ion channels, TRPV and TRPN, are restricted to the proximal and distal subcompartments, respectively. To understand the mechanisms underlying the sub-ciliary segregation of the two TRPs, we analyzed their localization under various conditions. In developing chordotonal cilia, TRPN was directly targeted to the ciliary tip from the beginning of its appearance and was retained in the distal subcompartment throughout development, whereas the ciliary localization of TRPV was considerably delayed. Lack of intraflagella transport-related proteins affected TRPV from the initial stage of its pre-ciliary trafficking, whereas it affected TRPN from the ciliary entry stage. The ectopic expression of the two TRP channels in both ciliated and nonciliated cells revealed their intrinsic properties related to their localization. Taken together, our results suggest that subciliary segregation of the two TRP channels relies on their distinct intrinsic properties, and begins at the initial stage of their pre-ciliary trafficking.
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Affiliation(s)
- Youngtae Kwon
- Department of Life Sciences, University of Seoul, Seoul 02504, Korea
| | - Jeongmi Lee
- Department of Life Sciences, University of Seoul, Seoul 02504, Korea
| | - Yun Doo Chung
- Department of Life Sciences, University of Seoul, Seoul 02504, Korea
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17
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Pischedda A, Shahandeh MP, Turner TL. The Loci of Behavioral Evolution: Evidence That Fas2 and tilB Underlie Differences in Pupation Site Choice Behavior between Drosophila melanogaster and D. simulans. Mol Biol Evol 2020; 37:864-880. [PMID: 31774527 DOI: 10.1093/molbev/msz274] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The behaviors of closely related species can be remarkably different, and these differences have important ecological and evolutionary consequences. Although the recent boom in genotype-phenotype studies has led to a greater understanding of the genetic architecture and evolution of a variety of traits, studies identifying the genetic basis of behaviors are, comparatively, still lacking. This is likely because they are complex and environmentally sensitive phenotypes, making them difficult to measure reliably for association studies. The Drosophila species complex holds promise for addressing these challenges, as the behaviors of closely related species can be readily assayed in a common environment. Here, we investigate the genetic basis of an evolved behavioral difference, pupation site choice, between Drosophila melanogaster and D. simulans. In this study, we demonstrate a significant contribution of the X chromosome to the difference in pupation site choice behavior between these species. Using a panel of X-chromosome deficiencies, we screened the majority of the X chromosome for causal loci and identified two regions associated with this X-effect. We then collect gene disruption and RNAi data supporting a single gene that affects pupation behavior within each region: Fas2 and tilB. Finally, we show that differences in tilB expression correlate with the differences in pupation site choice behavior between species. This evidence associating two genes with differences in a complex, environmentally sensitive behavior represents the first step toward a functional and evolutionary understanding of this behavioral divergence.
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Affiliation(s)
- Alison Pischedda
- Department of Biology, Barnard College, Columbia University, New York, NY
| | - Michael P Shahandeh
- Department of Ecology, Evolution, and Marine Biology, University of California Santa Barbara, Santa Barbara, CA
| | - Thomas L Turner
- Department of Ecology, Evolution, and Marine Biology, University of California Santa Barbara, Santa Barbara, CA
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18
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RNA interference supports a role for Nanchung-Inactive in mechanotransduction by the cockroach, Periplaneta americana, tactile spine. INVERTEBRATE NEUROSCIENCE 2020; 20:1. [PMID: 31960127 DOI: 10.1007/s10158-019-0234-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Accepted: 12/26/2019] [Indexed: 12/24/2022]
Abstract
Proteins encoded by nanchung, inactive, nompC and piezo genes have been shown to play crucial roles in the initial detection of mechanical force by various insect auditory neurons, nociceptors and touch receptors. Most of this previous research has been performed on the larval and adult fruit fly, Drosophila melanogaster. We identified and assembled all four homologous genes in transcriptomes from the cockroach, Periplaneta americana. Injection of long double-stranded RNA (dsRNA) into the adult cockroach abdomen successfully reduced the expression of each gene, as measured by quantitative PCR (RT-qPCR). A simple electrophysiological assay was used to record action potential firing in afferent nerves of cockroach femoral tactile spines in response to a standardized mechanical step displacement. Responses of nanchung knockdown animals were significantly reduced compared to matched sham-injected animals at 14 and 21 days after injection, and inactive knockdowns similarly at 21 days. In contrast, responses of nompC and piezo knockdowns were unchanged. Our results support a model in which Nanchung and Inactive proteins combine to form a part of the mechanotransduction mechanism in the cockroach tactile spine.
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19
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Blagburn JM. A new method of recording from the giant fiber of Drosophila melanogaster shows that the strength of its auditory inputs remains constant with age. PLoS One 2020; 15:e0224057. [PMID: 31910219 PMCID: PMC6946141 DOI: 10.1371/journal.pone.0224057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 12/13/2019] [Indexed: 11/19/2022] Open
Abstract
There have been relatively few studies of how central synapses age in adult Drosophila melanogaster. In this study we investigate the aging of the synaptic inputs to the Giant Fiber (GF) from auditory Johnston's Organ neurons (JONs). In previously published experiments an indirect assay of this synaptic connection was used; here we describe a new, more direct assay, which allows reliable detection of the GF action potential in the neck connective, and long term recording of its responses to sound. Genetic poisoning using diphtheria toxin expressed in the GF with R68A06-GAL4 was used to confirm that this signal indeed arose from the GF and not from other descending neurons. As before, the sound-evoked action potentials (SEPs) in the antennal nerve were recorded via an electrode inserted at the base of the antenna. It was noted that an action potential in the GF elicited an antennal twitch, which in turn evoked a mechanosensory response from the JONs in the absence of sound. We then used these extracellular recording techniques in males and female of different ages to quantify the response of the JONs to a brief sound impulse, and also to measure the strength of the connection between the JONs and the GF. At no age was there any significant difference between males and females, for any of the parameters measured. The sensitivity of the JONs to a sound impulse approximately doubled between 1 d and 10 d after eclosion, which corresponds to the period when most mating is taking place. Subsequently JON sensitivity decreased with age, being approximately half as sensitive at 20 d and one-third as sensitive at 50 d, as compared to 10 d. However, the strength of the connection between the auditory input and the GF itself remained unchanged with age, although it did show some variability that could mask any small changes.
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Affiliation(s)
- Jonathan M. Blagburn
- Institute of Neurobiology, University of Puerto Rico Medical Sciences Campus, San Juan, PR, United States of America
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20
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Zhao B, Sun J, Zhang X, Mo H, Niu Y, Li Q, Wang L, Zhong Y. Long-term memory is formed immediately without the need for protein synthesis-dependent consolidation in Drosophila. Nat Commun 2019; 10:4550. [PMID: 31591396 PMCID: PMC6779902 DOI: 10.1038/s41467-019-12436-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2019] [Accepted: 09/04/2019] [Indexed: 12/21/2022] Open
Abstract
It is believed that long-term memory (LTM) cannot be formed immediately because it must go through a protein synthesis-dependent consolidation process. However, the current study uses Drosophila aversive olfactory conditioning to show that such processes are dispensable for context-dependent LTM (cLTM). Single-trial conditioning yields cLTM that is formed immediately in a protein-synthesis independent manner and is sustained over 14 days without decay. Unlike retrieval of traditional LTM, which requires only the conditioned odour and is mediated by mushroom-body neurons, cLTM recall requires both the conditioned odour and reinstatement of the training-environmental context. It is mediated through lateral-horn neurons that connect to multiple sensory brain regions. The cLTM cannot be retrieved if synaptic transmission from any one of these centres is blocked, with effects similar to those of altered encoding context during retrieval. The present study provides strong evidence that long-term memory can be formed easily without the need for consolidation. New protein synthesis is known to be indispensable for the consolidation of long-term memory. Here, the authors report that an olfactory memory can be successfully recalled after 14 days without protein synthesis when the training context is also provided in addition to the conditioned odor.
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Affiliation(s)
- Bohan Zhao
- Tsinghua-Peking Center for Life Sciences, IDG/McGovern Institute for Brain Research and School of Life Sciences, Tsinghua University, 100084, Beijing, China
| | - Jiameng Sun
- Tsinghua-Peking Center for Life Sciences, IDG/McGovern Institute for Brain Research and School of Life Sciences, Tsinghua University, 100084, Beijing, China
| | - Xuchen Zhang
- Tsinghua-Peking Center for Life Sciences, IDG/McGovern Institute for Brain Research and School of Life Sciences, Tsinghua University, 100084, Beijing, China
| | - Han Mo
- Tsinghua-Peking Center for Life Sciences, IDG/McGovern Institute for Brain Research and School of Life Sciences, Tsinghua University, 100084, Beijing, China
| | - Yijun Niu
- Tsinghua-Peking Center for Life Sciences, IDG/McGovern Institute for Brain Research and School of Life Sciences, Tsinghua University, 100084, Beijing, China
| | - Qian Li
- Tsinghua-Peking Center for Life Sciences, IDG/McGovern Institute for Brain Research and School of Life Sciences, Tsinghua University, 100084, Beijing, China
| | - Lianzhang Wang
- Tsinghua-Peking Center for Life Sciences, IDG/McGovern Institute for Brain Research and School of Life Sciences, Tsinghua University, 100084, Beijing, China
| | - Yi Zhong
- Tsinghua-Peking Center for Life Sciences, IDG/McGovern Institute for Brain Research and School of Life Sciences, Tsinghua University, 100084, Beijing, China.
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21
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Zhou Y, Cao LH, Sui XW, Guo XQ, Luo DG. Mechanosensory circuits coordinate two opposing motor actions in Drosophila feeding. SCIENCE ADVANCES 2019; 5:eaaw5141. [PMID: 31131327 PMCID: PMC6531006 DOI: 10.1126/sciadv.aaw5141] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Accepted: 04/17/2019] [Indexed: 05/29/2023]
Abstract
Mechanoreception detects physical forces in the senses of hearing, touch, and proprioception. Here, we show that labellar mechanoreception wires two motor circuits to facilitate and terminate Drosophila feeding. Using patch-clamp recordings, we identified mechanosensory neurons (MSNs) in taste pegs of the inner labella and taste bristles of the outer labella, both of which rely on the same mechanoreceptor, NOMPC (no mechanoreceptor potential C), to transduce mechanical deflection. Connecting with distinct brain motor circuits, bristle MSNs drive labellar spread to facilitate feeding and peg MSNs elicit proboscis retraction to terminate feeding. Bitter sense modulates these two mechanosensory circuits in opposing manners, preventing labellar spread by bristle MSNs and promoting proboscis retraction by peg MSNs. Together, these labeled-line circuits enable labellar peg and bristle MSNs to use the same mechanoreceptors to direct opposing feeding actions and differentially integrate gustatory information in shaping feeding decisions.
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Affiliation(s)
- Yao Zhou
- State Key Laboratory of Membrane Biology, College of Life Sciences, Peking University, Beijing 100871, China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- College of Life Sciences, Peking University, Beijing 100871, China
| | - Li-Hui Cao
- State Key Laboratory of Membrane Biology, College of Life Sciences, Peking University, Beijing 100871, China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- College of Life Sciences, Peking University, Beijing 100871, China
- Center for Quantitative Biology, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Xiu-Wen Sui
- Center for Quantitative Biology, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
| | - Xiao-Qing Guo
- State Key Laboratory of Membrane Biology, College of Life Sciences, Peking University, Beijing 100871, China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- College of Life Sciences, Peking University, Beijing 100871, China
| | - Dong-Gen Luo
- State Key Laboratory of Membrane Biology, College of Life Sciences, Peking University, Beijing 100871, China
- PKU-IDG/McGovern Institute for Brain Research, Peking University, Beijing 100871, China
- Peking-Tsinghua Center for Life Sciences, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
- College of Life Sciences, Peking University, Beijing 100871, China
- Center for Quantitative Biology, Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China
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22
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Li T, Bellen HJ, Groves AK. Using Drosophila to study mechanisms of hereditary hearing loss. Dis Model Mech 2018; 11:11/6/dmm031492. [PMID: 29853544 PMCID: PMC6031363 DOI: 10.1242/dmm.031492] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Johnston's organ - the hearing organ of Drosophila - has a very different structure and morphology to that of the hearing organs of vertebrates. Nevertheless, it is becoming clear that vertebrate and invertebrate auditory organs share many physiological, molecular and genetic similarities. Here, we compare the molecular and cellular features of hearing organs in Drosophila with those of vertebrates, and discuss recent evidence concerning the functional conservation of Usher proteins between flies and mammals. Mutations in Usher genes cause Usher syndrome, the leading cause of human deafness and blindness. In Drosophila, some Usher syndrome proteins appear to physically interact in protein complexes that are similar to those described in mammals. This functional conservation highlights a rational role for Drosophila as a model for studying hearing, and for investigating the evolution of auditory organs, with the aim of advancing our understanding of the genes that regulate human hearing and the pathogenic mechanisms that lead to deafness.
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Affiliation(s)
- Tongchao Li
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Hugo J Bellen
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA.,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA.,Howard Hughes Medical Institute, Baylor College of Medicine, Houston, TX 77030, USA.,Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
| | - Andrew K Groves
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA .,Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA.,Department of Neuroscience, Baylor College of Medicine, Houston, TX 77030, USA
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23
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Patella P, Wilson RI. Functional Maps of Mechanosensory Features in the Drosophila Brain. Curr Biol 2018; 28:1189-1203.e5. [PMID: 29657118 PMCID: PMC5952606 DOI: 10.1016/j.cub.2018.02.074] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2018] [Revised: 02/19/2018] [Accepted: 02/27/2018] [Indexed: 01/04/2023]
Abstract
Johnston's organ is the largest mechanosensory organ in Drosophila. It contributes to hearing, touch, vestibular sensing, proprioception, and wind sensing. In this study, we used in vivo 2-photon calcium imaging and unsupervised image segmentation to map the tuning properties of Johnston's organ neurons (JONs) at the site where their axons enter the brain. We then applied the same methodology to study two key brain regions that process signals from JONs: the antennal mechanosensory and motor center (AMMC) and the wedge, which is downstream of the AMMC. First, we identified a diversity of JON response types that tile frequency space and form a rough tonotopic map. Some JON response types are direction selective; others are specialized to encode amplitude modulations over a specific range (dynamic range fractionation). Next, we discovered that both the AMMC and the wedge contain a tonotopic map, with a significant increase in tonotopy-and a narrowing of frequency tuning-at the level of the wedge. Whereas the AMMC tonotopic map is unilateral, the wedge tonotopic map is bilateral. Finally, we identified a subregion of the AMMC/wedge that responds preferentially to the coherent rotation of the two mechanical organs in the same angular direction, indicative of oriented steady air flow (directional wind). Together, these maps reveal the broad organization of the primary and secondary mechanosensory regions of the brain. They provide a framework for future efforts to identify the specific cell types and mechanisms that underlie the hierarchical re-mapping of mechanosensory information in this system.
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Affiliation(s)
- Paola Patella
- Department of Neurobiology, Harvard Medical School, 220 Longwood Ave., Boston, MA 02115, USA
| | - Rachel I Wilson
- Department of Neurobiology, Harvard Medical School, 220 Longwood Ave., Boston, MA 02115, USA.
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24
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Scholz N, Monk KR, Kittel RJ, Langenhan T. Adhesion GPCRs as a Putative Class of Metabotropic Mechanosensors. Handb Exp Pharmacol 2017; 234:221-247. [PMID: 27832490 DOI: 10.1007/978-3-319-41523-9_10] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Adhesion GPCRs as mechanosensors. Different aGPCR homologs and their cognate ligands have been described in settings, which suggest that they function in a mechanosensory capacity. For details, see text G protein-coupled receptors (GPCRs) constitute the most versatile superfamily of biosensors. This group of receptors is formed by hundreds of GPCRs, each of which is tuned to the perception of a specific set of stimuli a cell may encounter emanating from the outside world or from internal sources. Most GPCRs are receptive for chemical compounds such as peptides, proteins, lipids, nucleotides, sugars, and other organic compounds, and this capacity is utilized in several sensory organs to initiate visual, olfactory, gustatory, or endocrine signals. In contrast, GPCRs have only anecdotally been implicated in the perception of mechanical stimuli. Recent studies, however, show that the family of adhesion GPCRs (aGPCRs), which represents a large panel of over 30 homologs within the GPCR superfamily, displays molecular design and expression patterns that are compatible with receptivity toward mechanical cues (Fig. 1). Here, we review physiological and molecular principles of established mechanosensors, discuss their relevance for current research of the mechanosensory function of aGPCRs, and survey the current state of knowledge on aGPCRs as mechanosensing molecules.
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Affiliation(s)
- Nicole Scholz
- Department of Neurophysiology, Institute of Physiology, University of Würzburg, Röntgenring 9, Würzburg, 97070, Germany.
| | - Kelly R Monk
- Department of Developmental Biology, Hope Center for Neurologic Disorders, Washington University School of Medicine, St. Louis, 63110, MO, USA
| | - Robert J Kittel
- Department of Neurophysiology, Institute of Physiology, University of Würzburg, Röntgenring 9, Würzburg, 97070, Germany
| | - Tobias Langenhan
- Department of Neurophysiology, Institute of Physiology, University of Würzburg, Röntgenring 9, Würzburg, 97070, Germany.
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25
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Abstract
Aggression is a universal social behavior important for the acquisition of food, mates, territory, and social status. Aggression in Drosophila is context-dependent and can thus be expected to involve inputs from multiple sensory modalities. Here, we use mechanical disruption and genetic approaches in Drosophila melanogaster to identify hearing as an important sensory modality in the context of intermale aggressive behavior. We demonstrate that neuronal silencing and targeted knockdown of hearing genes in the fly's auditory organ elicit abnormal aggression. Further, we show that exposure to courtship or aggression song has opposite effects on aggression. Our data define the importance of hearing in the control of Drosophila intermale aggression and open perspectives to decipher how hearing and other sensory modalities are integrated at the neural circuit level.
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26
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Park J, Lee N, Kavoussi A, Seo JT, Kim CH, Moon SJ. Ciliary Phosphoinositide Regulates Ciliary Protein Trafficking in Drosophila. Cell Rep 2016; 13:2808-16. [PMID: 26723017 DOI: 10.1016/j.celrep.2015.12.009] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Revised: 11/16/2015] [Accepted: 11/25/2015] [Indexed: 10/22/2022] Open
Abstract
Cilia are highly specialized antennae-like cellular organelles. Inositol polyphosphate 5-phosphatase E (INPP5E) converts PI(4,5)P2 into PI4P and is required for proper ciliary function. Although Inpp5e mutations are associated with ciliopathies in humans and mice, the precise molecular role INPP5E plays in cilia remains unclear. Here, we report that Drosophila INPP5E (dINPP5E) regulates ciliary protein trafficking by controlling the phosphoinositide composition of ciliary membranes. Mutations in dInpp5e lead to hearing deficits due to the mislocalization of dTULP and mechanotransduction channels, Inactive and NOMPC, in chordotonal cilia. Both loss of dINPP5E and ectopic expression of the phosphatidylinositol-4-phosphate 5-kinase Skittles increase PI(4,5)P2 levels in the ciliary base. The fact that Skittles expression phenocopies the dInpp5e mutants confirms a central role for PI(4,5)P2 in the regulation of dTULP, Inactive, and NOMPC localization. These data suggest that the spatial localization and levels of PI(4,5)P2 in ciliary membranes are important regulators of ciliary trafficking and function.
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Affiliation(s)
- Jina Park
- Department of Oral Biology, Yonsei University College of Dentistry, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea
| | - Nayoung Lee
- Department of Oral Biology, Yonsei University College of Dentistry, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea
| | - Adriana Kavoussi
- Department of Pharmacology, Brain Research Institute, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea; Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Jeong Taeg Seo
- Department of Oral Biology, Yonsei University College of Dentistry, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea
| | - Chul Hoon Kim
- Department of Pharmacology, Brain Research Institute, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea; Severance Biomedical Science Institute, Yonsei University College of Medicine, Seoul 03722, Korea.
| | - Seok Jun Moon
- Department of Oral Biology, Yonsei University College of Dentistry, 50-1 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea.
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A Mechanosensory Circuit that Mixes Opponent Channels to Produce Selectivity for Complex Stimulus Features. Neuron 2016; 92:888-901. [PMID: 27974164 DOI: 10.1016/j.neuron.2016.09.059] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2016] [Revised: 08/16/2016] [Accepted: 09/27/2016] [Indexed: 01/26/2023]
Abstract
Johnston's organ is the largest mechanosensory organ in Drosophila; it analyzes movements of the antenna due to sound, wind, gravity, and touch. Different Johnston's organ neurons (JONs) encode distinct stimulus features. Certain JONs respond in a sustained manner to steady displacements, and these JONs subdivide into opponent populations that prefer push or pull displacements. Here, we describe neurons in the brain (aPN3 neurons) that combine excitation and inhibition from push/pull JONs in different ratios. Consequently, different aPN3 neurons are sensitive to movement in different parts of the antenna's range, at different frequencies, or at different amplitude modulation rates. We use a model to show how the tuning of aPN3 neurons can arise from rectification and temporal filtering in JONs, followed by mixing of JON signals in different proportions. These results illustrate how several canonical neural circuit components-rectification, opponency, and filtering-can combine to produce selectivity for complex stimulus features.
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28
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Majeski HE, Yang J. The 2016 John J. Abel Award Lecture: Targeting the Mechanical Microenvironment in Cancer. Mol Pharmacol 2016; 90:744-754. [PMID: 27742780 DOI: 10.1124/mol.116.106765] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 10/13/2016] [Indexed: 12/14/2022] Open
Abstract
Past decades of cancer research have mainly focused on the role of various extracellular and intracellular biochemical signals on cancer progression and metastasis. Recent studies suggest an important role of mechanical forces in regulating cellular behaviors. This review first provides an overview of the mechanobiology research field. Then we specially focus on mechanotransduction pathways in cancer progression and describe in detail the key signaling components of such mechanotransduction pathways and extracellular matrix components that are altered in cancer. Although our understanding of mechanoregulation in cancer is still in its infancy, some agents against key mechanoregulators have been developed and will be discussed to explore the potential of pharmacologically targeting mechanotransduction in cancer.
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Affiliation(s)
- Hannah E Majeski
- Department of Pharmacology (H.E.M., J.Y.), Department of Pediatrics (J.Y.), and Biomedical Sciences Graduate Program (H.E.M., J.Y.), Moores Cancer Center, University of California, San Diego, La Jolla, California
| | - Jing Yang
- Department of Pharmacology (H.E.M., J.Y.), Department of Pediatrics (J.Y.), and Biomedical Sciences Graduate Program (H.E.M., J.Y.), Moores Cancer Center, University of California, San Diego, La Jolla, California
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29
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Cattaneo AM, Bengtsson JM, Montagné N, Jacquin-Joly E, Rota-Stabelli O, Salvagnin U, Bassoli A, Witzgall P, Anfora G. TRPA5, an Ankyrin Subfamily Insect TRP Channel, is Expressed in Antennae of Cydia pomonella (Lepidoptera: Tortricidae) in Multiple Splice Variants. JOURNAL OF INSECT SCIENCE (ONLINE) 2016; 16:83. [PMID: 27638948 PMCID: PMC5026476 DOI: 10.1093/jisesa/iew072] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 07/13/2016] [Indexed: 05/16/2023]
Abstract
Transient receptor potential (TRP) channels are an ancient family of cation channels, working as metabotropic triggers, which respond to physical and chemical environmental cues. Perception of chemical signals mediate reproductive behaviors and is therefore an important target for sustainable management tactics against the codling moth Cydia pomonella L. (Lepidoptera: Tortricidae). However, olfactory behavior strongly depends on diel periodicity and correlation of chemical with physical cues, like temperature, and physical cues thus essentially contribute to the generation of behavioral response. From an antennal transcriptome generated by next generation sequencing, we characterized five candidate TRPs in the codling moth. The coding DNA sequence of one of these was extended to full length, and phylogenetic investigation revealed it to be orthologous of the TRPA5 genes, reported in several insect genomes as members of the insect TRPA group with unknown function but closely related to the thermal sensor pyrexia Reverse transcription PCR revealed the existence of five alternate splice forms of CpTRPA5. Identification of a novel TRPA and its splice forms in codling moth antennae open for investigation of their possible sensory roles and implications in behavioral responses related to olfaction.
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Affiliation(s)
- Alberto Maria Cattaneo
- Research and Innovation Centre, Agricultural Entomology - Fondazione Edmund Mach, via E. Mach, 1 38010 San Michele all'Adige, Italy
| | - Jonas Martin Bengtsson
- Department of Zoology, Stockholm University, Svante Arrhenius väg 18 B, Stockholm 106 91, Sweden
| | - Nicolas Montagné
- Sorbonne Universités - UPMC, Institute of Ecology & Environmental Sciences of Paris, 4 Place Jussieu 75005 Paris, France
| | - Emmanuelle Jacquin-Joly
- INRA, Institute of Ecology and Environmental Sciences of Paris, Saint Cyr Road, Versailles 78026, France
| | - Omar Rota-Stabelli
- Research and Innovation Centre, Agricultural Entomology - Fondazione Edmund Mach, via E. Mach, 1 38010 San Michele all'Adige, Italy
| | - Umberto Salvagnin
- Research and Innovation Centre, Agricultural Entomology - Fondazione Edmund Mach, via E. Mach, 1 38010 San Michele all'Adige, Italy
| | - Angela Bassoli
- DeFENS, Department of Food, Nutritional and Environmental Sciences - Università degli Studi di Milano, Via Celoria 2 20133, Milan, Italy
| | - Peter Witzgall
- Chemical Ecology Unit, Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Box 102 SE-23053, Alnarp, Sweden
| | - Gianfranco Anfora
- Research and Innovation Centre, Agricultural Entomology - Fondazione Edmund Mach, via E. Mach, 1 38010 San Michele all'Adige, Italy
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Kay AR, Raccuglia D, Scholte J, Sivan-Loukianova E, Barwacz CA, Armstrong SR, Guymon CA, Nitabach MN, Eberl DF. Goggatomy: A Method for Opening Small Cuticular Compartments in Arthropods for Physiological Experiments. Front Physiol 2016; 7:398. [PMID: 27695420 PMCID: PMC5025716 DOI: 10.3389/fphys.2016.00398] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2016] [Accepted: 08/26/2016] [Indexed: 11/30/2022] Open
Abstract
Most sense organs of arthropods are ensconced in small exoskeletal compartments that hinder direct access to plasma membranes. We have developed a method for exposing live sensory and supporting cells in such structures. The technique uses a viscous light cured resin to embed and support the structure, which is then sliced with a sharp blade. We term the procedure a “goggatomy,” from the Khoisan word for a bug, gogga. To demonstrate the utility of the method we show that it can be used to expose the auditory chordotonal organs in the second antennal segment and the olfactory receptor neurons in the third antennal segment of Drosophila melanogaster, preserving the transduction machinery. The procedure can also be used on other small arthropods, like mosquitoes and mites to expose a variety of cells.
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Affiliation(s)
- Alan R Kay
- Department of Biology, University of Iowa Iowa, IA, USA
| | - Davide Raccuglia
- Department of Cellular and Molecular Physiology, Yale University New Haven, CT, USA
| | - Jon Scholte
- Department of Chemical Engineering, University of Iowa Iowa, IA, USA
| | | | | | | | - C Allan Guymon
- Department of Chemical Engineering, University of Iowa Iowa, IA, USA
| | - Michael N Nitabach
- Department of Cellular and Molecular Physiology, Yale University New Haven, CT, USA
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31
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Investigating the Performance of a Fractal Ultrasonic Transducer Under Varying System Conditions. Symmetry (Basel) 2016. [DOI: 10.3390/sym8060043] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
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Lee J, Chung YD. Ciliary subcompartments: how are they established and what are their functions? BMB Rep 2016; 48:380-7. [PMID: 25936781 PMCID: PMC4577287 DOI: 10.5483/bmbrep.2015.48.7.084] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2015] [Indexed: 12/15/2022] Open
Abstract
Cilia are conserved subcellular organelles with diverse sensory and developmental roles. Recently, they have emerged as crucial organelles whose dysfunction causes a wide spectrum of disorders called ciliopathies. Recent studies on the pathological mechanisms underlying ciliopathies showed that the ciliary compartment is further divided into subdomains with specific roles in the biogenesis, maintenance and function of cilia. Several conserved sets of molecules that play specific roles in each subcompartment have been discovered. Here we review recent progress on our understanding of ciliary subcompartments, especially focusing on the molecules required for their structure and/or function. [BMB Reports 2015; 48(7): 380-387]
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Affiliation(s)
- Jeongmi Lee
- Department of Life Science, University of Seoul, Seoul 130-743, Korea
| | - Yun Doo Chung
- Department of Life Science, University of Seoul, Seoul 130-743, Korea
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33
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Zheng Y, Mennella V, Marks S, Wildonger J, Elnagdi E, Agard D, Megraw TL. The Seckel syndrome and centrosomal protein Ninein localizes asymmetrically to stem cell centrosomes but is not required for normal development, behavior, or DNA damage response in Drosophila. Mol Biol Cell 2016; 27:1740-52. [PMID: 27053665 PMCID: PMC4884065 DOI: 10.1091/mbc.e15-09-0655] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Accepted: 03/28/2016] [Indexed: 12/21/2022] Open
Abstract
Ninein associates with the microtubule regulator γ-tubulin, regulates microtubule assembly, and localizes to centrosomes and noncentrosomal microtubule-organizing centers in Drosophila. Ninein localizes to stem cell centrosomes asymmetrically, with a bias for the daughter centrosome. Remarkably, Ninein is dispensable for development, fertility, or viability. Ninein (Nin) is a centrosomal protein whose gene is mutated in Seckel syndrome (SCKL, MIM 210600), an inherited recessive disease that results in primordial dwarfism, cognitive deficiencies, and increased sensitivity to genotoxic stress. Nin regulates neural stem cell self-renewal, interkinetic nuclear migration, and microtubule assembly in mammals. Nin is evolutionarily conserved, yet its role in cell division and development has not been investigated in a model organism. Here we characterize the single Nin orthologue in Drosophila. Drosophila Nin localizes to the periphery of the centrosome but not at centriolar structures as in mammals. However, Nin shares the property of its mammalian orthologue of promoting microtubule assembly. In neural and germline stem cells, Nin localizes asymmetrically to the younger (daughter) centrosome, yet it is not required for the asymmetric division of stem cells. In wing epithelia and muscle, Nin localizes to noncentrosomal microtubule-organizing centers. Surprisingly, loss of nin expression from a nin mutant does not significantly affect embryonic and brain development, fertility, or locomotor performance of mutant flies or their survival upon exposure to DNA-damaging agents. Although it is not essential, our data suggest that Nin plays a supportive role in centrosomal and extracentrosomal microtubule organization and asymmetric stem cell division.
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Affiliation(s)
- Yiming Zheng
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL 32306-4300
| | - Vito Mennella
- Department of Biochemistry, University of Toronto, Toronto, M5G 0A4, Canada Cell Biology Program, The Hospital for Sick Children, Toronto, M5G 1X8, Canada
| | - Steven Marks
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL 32306-4300
| | - Jill Wildonger
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706
| | - Esraa Elnagdi
- Department of Biochemistry, University of Toronto, Toronto, M5G 0A4, Canada Cell Biology Program, The Hospital for Sick Children, Toronto, M5G 1X8, Canada
| | - David Agard
- The Howard Hughes Medical Institute and Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA 94143-2240
| | - Timothy L Megraw
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL 32306-4300
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34
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Comeron JM, Reed J, Christie M, Jacobs JS, Dierdorff J, Eberl DF, Manak JR. A Mismatch EndoNuclease Array-Based Methodology (MENA) for Identifying Known SNPs or Novel Point Mutations. MICROARRAYS (BASEL, SWITZERLAND) 2016; 5:E7. [PMID: 27600073 PMCID: PMC5003483 DOI: 10.3390/microarrays5020007] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 03/21/2016] [Accepted: 03/30/2016] [Indexed: 11/30/2022]
Abstract
Accurate and rapid identification or confirmation of single nucleotide polymorphisms (SNPs), point mutations and other human genomic variation facilitates understanding the genetic basis of disease. We have developed a new methodology (called MENA (Mismatch EndoNuclease Array)) pairing DNA mismatch endonuclease enzymology with tiling microarray hybridization in order to genotype both known point mutations (such as SNPs) as well as identify previously undiscovered point mutations and small indels. We show that our assay can rapidly genotype known SNPs in a human genomic DNA sample with 99% accuracy, in addition to identifying novel point mutations and small indels with a false discovery rate as low as 10%. Our technology provides a platform for a variety of applications, including: (1) genotyping known SNPs as well as confirming newly discovered SNPs from whole genome sequencing analyses; (2) identifying novel point mutations and indels in any genomic region from any organism for which genome sequence information is available; and (3) screening panels of genes associated with particular diseases and disorders in patient samples to identify causative mutations. As a proof of principle for using MENA to discover novel mutations, we report identification of a novel allele of the beethoven (btv) gene in Drosophila, which encodes a ciliary cytoplasmic dynein motor protein important for auditory mechanosensation.
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Affiliation(s)
- Josep M Comeron
- Department of Biology, University of Iowa, Iowa City, IA 52242, USA.
- Graduate Program in Genetics, University of Iowa, Iowa City, IA 52242, USA.
| | - Jordan Reed
- Department of Biology, University of Iowa, Iowa City, IA 52242, USA.
| | - Matthew Christie
- Department of Biology, University of Iowa, Iowa City, IA 52242, USA.
| | - Julia S Jacobs
- Department of Biology, University of Iowa, Iowa City, IA 52242, USA.
| | - Jason Dierdorff
- Department of Biology, University of Iowa, Iowa City, IA 52242, USA.
| | - Daniel F Eberl
- Department of Biology, University of Iowa, Iowa City, IA 52242, USA.
- Graduate Program in Genetics, University of Iowa, Iowa City, IA 52242, USA.
| | - J Robert Manak
- Department of Biology, University of Iowa, Iowa City, IA 52242, USA.
- Graduate Program in Genetics, University of Iowa, Iowa City, IA 52242, USA.
- Department of Pediatrics, University of Iowa, Iowa City, IA, 52242, USA.
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35
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Pézier AP, Jezzini SH, Bacon JP, Blagburn JM. Shaking B Mediates Synaptic Coupling between Auditory Sensory Neurons and the Giant Fiber of Drosophila melanogaster. PLoS One 2016; 11:e0152211. [PMID: 27043822 PMCID: PMC4833477 DOI: 10.1371/journal.pone.0152211] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 03/10/2016] [Indexed: 11/18/2022] Open
Abstract
The Johnston’s Organ neurons (JONs) form chemical and electrical synapses onto the giant fiber neuron (GF), as part of the neuronal circuit that mediates the GF escape response in Drosophila melanogaster. The purpose of this study was to identify which of the 8 Drosophila innexins (invertebrate gap junction proteins) mediates the electrical connection at this synapse. The GF is known to express Shaking B (ShakB), specifically the ShakB(N+16) isoform only, at its output synapses in the thorax. The shakB2 mutation disrupts these GF outputs and also abolishes JON-GF synaptic transmission. However, the identity of the innexin that forms the presynaptic hemichannels in the JONs remains unknown. We used electrophysiology, immunocytochemistry and dye injection, along with presynaptically-driven RNA interference, to investigate this question. The amplitude of the compound action potential recorded in response to sound from the base of the antenna (sound-evoked potential, or SEP) was reduced by RNAi of the innexins Ogre, Inx3, Inx6 and, to a lesser extent Inx2, suggesting that they could be required in JONs for proper development, excitability, or synchronization of action potentials. The strength of the JON-GF connection itself was reduced to background levels only by RNAi of shakB, not of the other seven innexins. ShakB knockdown prevented Neurobiotin coupling between GF and JONs and removed the plaques of ShakB protein immunoreactivity that are present at the region of contact. Specific shakB RNAi lines that are predicted to target the ShakB(L) or ShakB(N) isoforms alone did not reduce the synaptic strength, implying that it is ShakB(N+16) that is required in the presynaptic neurons. Overexpression of ShakB(N+16) in JONs caused the formation of ectopic dye coupling, whereas ShakB(N) prevented it altogether, supporting this conclusion and also suggesting that gap junction proteins may have an instructive role in synaptic target choice.
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Affiliation(s)
- Adeline P. Pézier
- Institute of Neurobiology, University of Puerto Rico Medical Sciences Campus, San Juan, Puerto Rico, United States of America
| | - Sami H. Jezzini
- Institute of Neurobiology, University of Puerto Rico Medical Sciences Campus, San Juan, Puerto Rico, United States of America
| | - Jonathan P. Bacon
- School of Life Sciences, University of Sussex, Brighton, United Kingdom
| | - Jonathan M. Blagburn
- Institute of Neurobiology, University of Puerto Rico Medical Sciences Campus, San Juan, Puerto Rico, United States of America
- * E-mail:
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36
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Leung JCK, Hilliker AJ, Rezai P. An integrated hybrid microfluidic device for oviposition-based chemical screening of adult Drosophila melanogaster. LAB ON A CHIP 2016; 16:709-719. [PMID: 26768402 DOI: 10.1039/c5lc01517k] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Chemical screening using Drosophila melanogaster (the fruit fly) is vital in drug discovery, agricultural, and toxicological applications. Oviposition (egg laying) on chemically-doped agar plates is an important read-out metric used to quantitatively assess the biological fitness and behavioral responses of Drosophila. Current oviposition-based chemical screening studies are inaccurate, labor-intensive, time-consuming, and inflexible due to the manual chemical doping of agar. In this paper, we have developed a novel hybrid agar-polydimethylsiloxane (PDMS) microfluidic device for single- and multi-concentration chemical dosing and on-chip oviposition screening of free-flying adult stage Drosophila. To achieve this, we have devised a novel technique to integrate agar with PDMS channels using ice as a sacrificial layer. Subsequently, we have conducted single-chemical toxicity and multiple choice chemical preference assays on adult Drosophila melanogaster using zinc and acetic acid at various concentrations. Our device has enabled us to 1) demonstrate that Drosophila is capable of sensing the concentration of different chemicals on a PDMS-agar microfluidic device, which plays significant roles in determining oviposition site selection and 2) investigate whether oviposition preference differs between single- and multi-concentration chemical environments. This device may be used to study fundamental and applied biological questions in Drosophila and other egg laying insects. It can also be extended in design to develop sophisticated and dynamic chemical dosing and high-throughput screening platforms in the future that are not easily achievable with the existing oviposition screening techniques.
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Affiliation(s)
- Jacob C K Leung
- Department of Mechanical Engineering, York University, BCEE 433B, 4700 Keele St, Toronto, ON M3J 1P3, Canada.
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37
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Abstract
Centrioles and cilia are highly conserved eukaryotic organelles. Drosophila melanogaster is a powerful genetic and cell biology model organism, extensively used to discover underlying mechanisms of centrosome and cilia biogenesis and function. Defects in centrosomes and cilia reduce fertility and affect different sensory functions, such as proprioception, olfaction, and hearing. The fly possesses a large diversity of ciliary structures and assembly modes, such as motile, immotile, and intraflagellar transport (IFT)-independent or IFT-dependent assembly. Moreover, all the diverse ciliated cells harbor centrioles at the base of the cilia, called basal bodies, making the fly an attractive model to better understand the biology of this organelle. This chapter describes protocols to visualize centrosomes and cilia by fluorescence and electron microscopy.
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38
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Abstract
The fruit fly, Drosophila melanogaster, is an invaluable model for auditory research. Advantages of using the fruit fly include its stereotyped behavior in response to a particular sound, and the availability of molecular-genetic tools to manipulate gene expression and cellular activity. Although the receiver type in fruit flies differs from that in mammals, the auditory systems of mammals and fruit flies are strikingly similar with regard to the level of development, transduction mechanism, mechanical amplification, and central projections. These similarities strongly support the use of the fruit fly to study the general principles of acoustic information processing. In this review, we introduce acoustic communication and discuss recent advances in our understanding on hearing in fruit flies. This article is part of a Special Issue entitled <Annual Reviews 2016>.
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Chen JV, Kao LR, Jana SC, Sivan-Loukianova E, Mendonça S, Cabrera OA, Singh P, Cabernard C, Eberl DF, Bettencourt-Dias M, Megraw TL. Rootletin organizes the ciliary rootlet to achieve neuron sensory function in Drosophila. J Cell Biol 2015; 211:435-53. [PMID: 26483560 PMCID: PMC4621839 DOI: 10.1083/jcb.201502032] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Accepted: 09/09/2015] [Indexed: 12/22/2022] Open
Abstract
Drosophila Rootletin organizes rootlets in sensory neurons, where it transmits multiple sensory inputs and maintains basal body cohesion, yet it is not required for cilium stability. Cilia are essential for cell signaling and sensory perception. In many cell types, a cytoskeletal structure called the ciliary rootlet links the cilium to the cell body. Previous studies indicated that rootlets support the long-term stability of some cilia. Here we report that Drosophila melanogaster Rootletin (Root), the sole orthologue of the mammalian paralogs Rootletin and C-Nap1, assembles into rootlets of diverse lengths among sensory neuron subtypes. Root mutant neurons lack rootlets and have dramatically impaired sensory function, resulting in behavior defects associated with mechanosensation and chemosensation. Root is required for cohesion of basal bodies, but the cilium structure appears normal in Root mutant neurons. We show, however, that normal rootlet assembly requires centrioles. The N terminus of Root contains a conserved domain and is essential for Root function in vivo. Ectopically expressed Root resides at the base of mother centrioles in spermatocytes and localizes asymmetrically to mother centrosomes in neuroblasts, both requiring Bld10, a basal body protein with varied functions.
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Affiliation(s)
- Jieyan V Chen
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL 32306
| | - Ling-Rong Kao
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL 32306
| | - Swadhin C Jana
- Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal
| | | | | | - Oscar A Cabrera
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL 32306
| | - Priyanka Singh
- Biozentrum, University of Basel, 4056 Basel, Switzerland
| | | | - Daniel F Eberl
- Biology Department, University of Iowa, Iowa City, IA 52242
| | | | - Timothy L Megraw
- Department of Biomedical Sciences, Florida State University, Tallahassee, FL 32306
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40
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Kim CS, Seong KM, Lee BS, Lee IK, Yang KH, Kim JY, Nam SY. Chronic low-dose γ-irradiation of Drosophila melanogaster larvae induces gene expression changes and enhances locomotive behavior. JOURNAL OF RADIATION RESEARCH 2015; 56:475-484. [PMID: 25792464 PMCID: PMC4426922 DOI: 10.1093/jrr/rru128] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Revised: 12/15/2014] [Accepted: 12/27/2014] [Indexed: 06/04/2023]
Abstract
Although radiation effects have been extensively studied, the biological effects of low-dose radiation (LDR) are controversial. This study investigates LDR-induced alterations in locomotive behavior and gene expression profiles of Drosophila melanogaster. We measured locomotive behavior using larval pupation height and the rapid iterative negative geotaxis (RING) assay after exposure to 0.1 Gy γ-radiation (dose rate of 16.7 mGy/h). We also observed chronic LDR effects on development (pupation and eclosion rates) and longevity (life span). To identify chronic LDR effects on gene expression, we performed whole-genome expression analysis using gene-expression microarrays, and confirmed the results using quantitative real-time PCR. The pupation height of the LDR-treated group at the first larval instar was significantly higher (∼2-fold increase in PHI value, P < 0.05). The locomotive behavior of LDR-treated male flies (∼3 - 5 weeks of age) was significantly increased by 7.7%, 29% and 138%, respectively (P < 0.01), but pupation and eclosion rates and life spans were not significantly altered. Genome-wide expression analysis identified 344 genes that were differentially expressed in irradiated larvae compared with in control larvae. We identified several genes belonging to larval behavior functional groups such as locomotion (1.1%), oxidation reduction (8.0%), and genes involved in conventional functional groups modulated by irradiation such as defense response (4.9%), and sensory and perception (2.5%). Four candidate genes were confirmed as differentially expressed genes in irradiated larvae using qRT-PCR (>2-fold change). These data suggest that LDR stimulates locomotion-related genes, and these genes can be used as potential markers for LDR.
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Affiliation(s)
- Cha Soon Kim
- Low-dose Radiation Research Team, Radiation Health Institute, Korea Hydro and Nuclear Power Co. Ltd, Seoul 132-703, Korea
| | - Ki Moon Seong
- National Radiation Emergency Medical Center, Korea Institute of Radiological and Medical Sciences, Seoul 139-736, Korea
| | - Byung Sub Lee
- Low-dose Radiation Research Team, Radiation Health Institute, Korea Hydro and Nuclear Power Co. Ltd, Seoul 132-703, Korea
| | - In Kyung Lee
- Low-dose Radiation Research Team, Radiation Health Institute, Korea Hydro and Nuclear Power Co. Ltd, Seoul 132-703, Korea
| | - Kwang Hee Yang
- Low-dose Radiation Research Team, Radiation Health Institute, Korea Hydro and Nuclear Power Co. Ltd, Seoul 132-703, Korea
| | - Ji-Young Kim
- Low-dose Radiation Research Team, Radiation Health Institute, Korea Hydro and Nuclear Power Co. Ltd, Seoul 132-703, Korea
| | - Seon Young Nam
- Low-dose Radiation Research Team, Radiation Health Institute, Korea Hydro and Nuclear Power Co. Ltd, Seoul 132-703, Korea
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41
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Leung JCK, Taylor-Kamall RW, Hilliker AJ, Rezai P. Agar-polydimethylsiloxane devices for quantitative investigation of oviposition behaviour of adult Drosophila melanogaster. BIOMICROFLUIDICS 2015; 9:034112. [PMID: 26180569 PMCID: PMC4482806 DOI: 10.1063/1.4922737] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2015] [Accepted: 06/08/2015] [Indexed: 06/04/2023]
Abstract
Drosophila melanogaster (fruit fly) is a model organism and its behaviours including oviposition (egg-laying) on agar substrates have been widely used for assessment of a variety of biological processes in flies. Physical and chemical properties of the substrate are the dominant factors affecting Drosophila's oviposition, but they have not been investigated precisely and parametrically with the existing manual approaches. As a result, many behavioral questions about Drosophila oviposition, such as the combined effects of the aforementioned substrate properties (e.g., exposure area, sugar content, and stiffness) on oviposition and viability, and their threshold values, are yet to be answered. In this paper, we have devised a simple, easily implementable, and novel methodology that allows for modification of physical and chemical composition of agar substrates in order to quantitatively study survival and oviposition of adult fruit flies in an accurate and repeatable manner. Agar substrates have been modified by surface patterning using single and hexagonally arrayed through-hole polydimethylsiloxane (PDMS) membranes with various diameters and interspacing, as well as by substrate stiffness and sugar content modification via alteration of chemical components. While pure PDMS substrates showed a significant lethal effect on flies, a 0.5 mm diameter through-hole access to agar was found to abruptly increase the survival of adult flies to more than 93%. Flies avoided ovipositing on pure PDMS and on top of substrates with 0.5 mm diameter agar exposure areas. At a hole diameter of 2 mm (i.e., 0.25% exposure area) or larger, eggs were observed to be laid predominately inside the through-holes and along the edges of the PDMS-agar interface, showing a trending increase in site selection with 4 mm (i.e., 1% exposure area threshold) demonstrating natural oviposition rates similar to pure agar. The surface-modified agar-PDMS hybrid devices and the threshold values reported for the substrate physical and chemical conditions affecting oviposition are novel; therefore, we advocate their use for future in-depth studies of oviposition behaviour in Drosophila melanogaster with accuracy and repeatability. The technique is also useful for development of novel assays for learning and decision-making studies as well as miniaturized devices for self-assembly of eggs and embryonic developmental investigations.
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Affiliation(s)
- Jacob C K Leung
- Department of Mechanical Engineering, Lassonde School of Engineering, York University , Toronto, Ontario M3J 1P3, Canada
| | | | - Arthur J Hilliker
- Department of Biology, York University , Toronto, Ontario M3J 1P3, Canada
| | - Pouya Rezai
- Department of Mechanical Engineering, Lassonde School of Engineering, York University , Toronto, Ontario M3J 1P3, Canada
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NOMPC-dependent mechanotransduction shapes the dendrite of proprioceptive neurons. Neurosci Lett 2015; 597:111-6. [PMID: 25916878 DOI: 10.1016/j.neulet.2015.04.033] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 04/20/2015] [Accepted: 04/21/2015] [Indexed: 02/04/2023]
Abstract
Animal locomotion depends on proprioceptive feedback which is generated by mechanosensory neurons. We recently demonstrated that the evolutionarily conserved stumble (stum) gene is essential for mechanical transduction in a group of proprioceptive neurons in Drosophila leg joints. A specialized dendritic ending of the stum-expressing neurons is stretched by changes in joint position, suggesting that the dendritic site is specifically tuned for joint proprioception. Here, we show that the stum-expressing neurons express the mechanosensory channel NOMPC. In nompC mutants responses to joint position were abolished, indicating that NOMPC is the mechanosensitive channel in stum-expressing neurons. The NOMPC protein had a similar subcellular distribution as STUM, being located specifically at the dendritic site that is stretched by joint motions, thus validating that this site is a specialized sensory compartment. In the absence of NOMPC the sensory portion of the dendrite was misshapen, generating membrane protrusions. Thus, we have shown that mechanical responsiveness at a specialized dendritic site is essential for determination of the fine dendritic structure. The abnormal morphology at the sensory compartment of non-active neurons suggests that the dendrite samples for a responsive anchoring site and stabilizes the structure that elicits the effective mechanotransduction.
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Abstract
Drosophila melanogaster is a powerful genetic model organism to understand the function of proteins in specific cellular processes. Cilia have been extensively studied in Drosophila playing various sensory functions that are essential for fly survival. Indeed, flies defective in cilia formation cannot walk, fly, or feed properly. Drosophila harbors different types of cilia that can be motile or immotile or that can show compartimentalized (intraflagellar transport (IFT)-dependent) or cytoplasmic (IFT-independent) mode of assembly. Therefore, Drosophila represents an advantageous model organism to study the function of novel ciliary candidates and to address specific questions such as their requirement for IFT-dependent processes versus other aspects of cilia-associated functions. This chapter describes protocols to visualize cilia by direct or indirect fluorescent labeling and protocols to analyze ciliary ultrastructure by electron microscopy.
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Bellemer A. Thermotaxis, circadian rhythms, and TRP channels in Drosophila. Temperature (Austin) 2015; 2:227-43. [PMID: 27227026 PMCID: PMC4843867 DOI: 10.1080/23328940.2015.1004972] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 12/31/2014] [Accepted: 01/01/2015] [Indexed: 01/24/2023] Open
Abstract
The fruit fly Drosophila melanogaster is a poikilothermic organism that must detect and respond to both fine and coarse changes in environmental temperature in order maintain optimal body temperature, synchronize behavior to daily temperature fluctuations, and to avoid potentially injurious environmental hazards. Members of the Transient Receptor Potential (TRP) family of cation channels are well known for their activation by changes in temperature and their essential roles in sensory transduction in both invertebrates and vertebrates. The Drosophila genome encodes 13 TRP channels, and several of these have key sensory transduction and modulatory functions in allowing larval and adult flies to make fine temperature discriminations to attain optimal body temperature, detect and avoid large environmental temperature fluctuations, and make rapid escape responses to acutely noxious stimuli. Drosophila use multiple, redundant signaling pathways and neural circuits to execute these behaviors in response to both increases and decreases in temperature of varying magnitudes and time scales. A plethora of powerful molecular and genetic tools and the fly's simple, well-characterized nervous system have given Drosophila neurobiologists a powerful platform to study the cellular and molecular mechanisms of TRP channel function and how these mechanisms are conserved in vertebrates, as well as how these channels function within sensorimotor circuits to generate both simple and complex thermosensory behaviors.
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Key Words
- A1, 1st Antennal Segment
- A2, 2nd Antennal Segment
- A3, 3rd Antennal Segment
- AC, Anterior Cell
- AL, Antennal Lobe
- AR, Arista
- Clk, Clock protein
- Cry, Cryptochrome
- Cyc, Cycle protein
- DN1, DN2, DN3, Dorsal Neuron group 1, 2, 3
- Dbt, Double Time protein
- Drosophila melanogaster
- GFP, Green Fluorescent Protein
- GPCR, G Protein-Coupled Receptor
- LN, Lateral Neuron
- LNd, Dorsal Lateral Neuron
- LNv, Ventral Lateral Neuron
- LPN, Lateral Posterior Neuron
- NEL, Nocifensive Escape Locomotion
- PAP, Proximal Antennal Protocerebrum
- PDF, Pigment Dispersing Factor
- PKD1, Polycistic Kidney Disease 1
- PLC, Phospholipase C
- Per, Period protein
- RNAi, RNA interference
- SAC, Sacculus
- SLPR, Superior Lateral Protocerebrum
- SOG, Suboesophageal Ganglion
- TRP channels
- TRP, Transient Receptor Potential
- TRPA, Transient Receptor Potential, group A (ankyrin repeat)
- TRPA1
- TRPC, Transient Receptor Potential, group C (canonical)
- TRPL, TRP-Like
- TRPM, Transient Receptor Potential, group M (melastatin)
- TRPP, Transient Receptor Potential, group P (polycystic)
- TRPV, Transient Receptor Potential, group V (vanilloid)
- Tim, Timeless protein
- VFP, Venus Fluorescent Protein
- circadian rhythms
- lLNv, Ventral Lateral Neuron, large cell body
- mdIV, Multidendritic Neuron, class IV
- nociception
- sLNv, Ventral Lateral Neuron, small cell body
- thermoTRP, thermosensitive TRP channel
- thermosensation
- thermotaxis
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Affiliation(s)
- Andrew Bellemer
- Department of Biology; Appalachian State University ; Boone, NC, USA
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45
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Mhatre N. Active amplification in insect ears: mechanics, models and molecules. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2014; 201:19-37. [PMID: 25502323 DOI: 10.1007/s00359-014-0969-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 11/15/2014] [Accepted: 11/17/2014] [Indexed: 12/29/2022]
Abstract
Active amplification in auditory systems is a unique and sophisticated mechanism that expends energy in amplifying the mechanical input to the auditory system, to increase its sensitivity and acuity. Although known for decades from vertebrates, active auditory amplification was only discovered in insects relatively recently. It was first discovered from two dipterans, mosquitoes and flies, who hear with their light and compliant antennae; only recently has it been observed in the stiffer and heavier tympanal ears of an orthopteran. The discovery of active amplification in two distinct insect lineages with independently evolved ears, suggests that the trait may be ancestral, and other insects may possess it as well. This opens up extensive research possibilities in the field of acoustic communication, not just in auditory biophysics, but also in behaviour and neurobiology. The scope of this review is to establish benchmarks for identifying the presence of active amplification in an auditory system and to review the evidence we currently have from different insect ears. I also review some of the models that have been posited to explain the mechanism, both from vertebrates and insects and then review the current mechanical, neurobiological and genetic evidence for each of these models.
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Affiliation(s)
- Natasha Mhatre
- School of Biological Sciences, University of Bristol, Woodland road, Bristol, BS8 1UG, UK,
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Kavlie RG, Fritz JL, Nies F, Göpfert MC, Oliver D, Albert JT, Eberl DF. Prestin is an anion transporter dispensable for mechanical feedback amplification in Drosophila hearing. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2014; 201:51-60. [PMID: 25412730 PMCID: PMC4282873 DOI: 10.1007/s00359-014-0960-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Revised: 10/21/2014] [Accepted: 10/25/2014] [Indexed: 12/12/2022]
Abstract
In mammals, the membrane-based protein Prestin confers unique electromotile properties to cochlear outer hair cells, which contribute to the cochlear amplifier. Like mammals, the ears of insects, such as those of Drosophila melanogaster, mechanically amplify sound stimuli and have also been reported to express Prestin homologs. To determine whether the D. melanogaster Prestin homolog (dpres) is required for auditory amplification, we generated and analyzed dpres mutant flies. We found that dpres is robustly expressed in the fly’s antennal ear. However, dpres mutant flies show normal auditory nerve responses, and intact non-linear amplification. Thus we conclude that, in D. melanogaster, auditory amplification is independent of Prestin. This finding resonates with prior phylogenetic analyses, which suggest that the derived motor function of mammalian Prestin replaced, or amended, an ancestral transport function. Indeed, we show that dpres encodes a functional anion transporter. Interestingly, the acquired new motor function in the phylogenetic lineage leading to birds and mammals coincides with loss of the mechanotransducer channel NompC (=TRPN1), which has been shown to be required for auditory amplification in flies. The advent of Prestin (or loss of NompC, respectively) may thus mark an evolutionary transition from a transducer-based to a Prestin-based mechanism of auditory amplification.
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Affiliation(s)
- Ryan G Kavlie
- The Ear Institute, University College London, 332 Gray's Inn Road, London, WC1X 8EE, UK
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Abstract
PURPOSE OF THE REVIEW This article presents research findings from two invertebrate model systems with potential to advance both the understanding of noise-induced hearing loss mechanisms and the development of putative therapies to reduce human noise damage. RECENT FINDINGS Work on sea anemone hair bundles, which resemble auditory hair cells, has revealed secretions that exhibit astonishing healing properties not only for damaged hair bundles, but also for vertebrate lateral line neuromasts. We present progress on identifying functional components of the secretions, and their mechanisms of repair. The second model, the Johnston's organ in Drosophila, is also genetically homologous to hair cells and shows noise-induced hearing loss similar to vertebrates. Drosophila offers genetic and molecular insight into noise sensitivity and pathways that can be manipulated to reduce stress and damage from noise. SUMMARY Using the comparative approach is a productive avenue to understanding basic mechanisms, in this case cellular responses to noise trauma. Expanding study of these systems may accelerate identification of strategies to reduce or prevent noise damage in the human ear.
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Affiliation(s)
- Kevin W Christie
- Department of Biology, The University of Iowa, Iowa City, Iowa 52246
| | - Daniel F. Eberl
- Department of Biology, The University of Iowa, Iowa City, Iowa 52246
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48
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Diggle CP, Moore DJ, Mali G, zur Lage P, Ait-Lounis A, Schmidts M, Shoemark A, Garcia Munoz A, Halachev MR, Gautier P, Yeyati PL, Bonthron DT, Carr IM, Hayward B, Markham AF, Hope JE, von Kriegsheim A, Mitchison HM, Jackson IJ, Durand B, Reith W, Sheridan E, Jarman AP, Mill P. HEATR2 plays a conserved role in assembly of the ciliary motile apparatus. PLoS Genet 2014; 10:e1004577. [PMID: 25232951 PMCID: PMC4168999 DOI: 10.1371/journal.pgen.1004577] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2013] [Accepted: 07/03/2014] [Indexed: 11/18/2022] Open
Abstract
Cilia are highly conserved microtubule-based structures that perform a variety of sensory and motility functions during development and adult homeostasis. In humans, defects specifically affecting motile cilia lead to chronic airway infections, infertility and laterality defects in the genetically heterogeneous disorder Primary Ciliary Dyskinesia (PCD). Using the comparatively simple Drosophila system, in which mechanosensory neurons possess modified motile cilia, we employed a recently elucidated cilia transcriptional RFX-FOX code to identify novel PCD candidate genes. Here, we report characterization of CG31320/HEATR2, which plays a conserved critical role in forming the axonemal dynein arms required for ciliary motility in both flies and humans. Inner and outer arm dyneins are absent from axonemes of CG31320 mutant flies and from PCD individuals with a novel splice-acceptor HEATR2 mutation. Functional conservation of closely arranged RFX-FOX binding sites upstream of HEATR2 orthologues may drive higher cytoplasmic expression of HEATR2 during early motile ciliogenesis. Immunoprecipitation reveals HEATR2 interacts with DNAI2, but not HSP70 or HSP90, distinguishing it from the client/chaperone functions described for other cytoplasmic proteins required for dynein arm assembly such as DNAAF1-4. These data implicate CG31320/HEATR2 in a growing intracellular pre-assembly and transport network that is necessary to deliver functional dynein machinery to the ciliary compartment for integration into the motile axoneme.
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Affiliation(s)
| | - Daniel J. Moore
- Centre for Integrative Physiology, School of Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Girish Mali
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine at The University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
| | - Petra zur Lage
- Centre for Integrative Physiology, School of Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Aouatef Ait-Lounis
- Department of Pathology and Immunology, Faculty of Medicine, Université de Genève, Geneva, Switzerland
| | - Miriam Schmidts
- Molecular Medicine Unit and Birth Defect Research Center, Institute of Child Health, University College London, London, United Kingdom
| | - Amelia Shoemark
- Paediatric Respiratory Department, Royal Brompton Hospital, London, United Kingdom
| | - Amaya Garcia Munoz
- Systems Biology Ireland, University College Dublin, Belfield, Dublin, Ireland
| | - Mihail R. Halachev
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine at The University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
| | - Philippe Gautier
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine at The University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
| | - Patricia L. Yeyati
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine at The University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
| | | | - Ian M. Carr
- School of Medicine, University of Leeds, Leeds, United Kingdom
| | - Bruce Hayward
- School of Medicine, University of Leeds, Leeds, United Kingdom
| | | | - Jilly E. Hope
- Centre for Integrative Physiology, School of Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
| | - Alex von Kriegsheim
- Systems Biology Ireland, University College Dublin, Belfield, Dublin, Ireland
| | - Hannah M. Mitchison
- Molecular Medicine Unit and Birth Defect Research Center, Institute of Child Health, University College London, London, United Kingdom
| | - Ian J. Jackson
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine at The University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
| | - Bénédicte Durand
- Centre de Génétique et de Physiologie Moléculaire et Cellulaire, UMR 5534 CNRS, Université Claude Bernard Lyon 1, Villeurbanne, France
| | - Walter Reith
- Department of Pathology and Immunology, Faculty of Medicine, Université de Genève, Geneva, Switzerland
| | - Eamonn Sheridan
- School of Medicine, University of Leeds, Leeds, United Kingdom
- * E-mail: (ES); (APJ); (PM)
| | - Andrew P. Jarman
- Centre for Integrative Physiology, School of Biomedical Sciences, University of Edinburgh, Edinburgh, United Kingdom
- * E-mail: (ES); (APJ); (PM)
| | - Pleasantine Mill
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine at The University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
- * E-mail: (ES); (APJ); (PM)
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49
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Bokolia NP, Mishra M. Hearing molecules, mechanism and transportation: modeled in Drosophila melanogaster. Dev Neurobiol 2014; 75:109-30. [PMID: 25081222 DOI: 10.1002/dneu.22221] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2014] [Revised: 07/29/2014] [Accepted: 07/29/2014] [Indexed: 01/19/2023]
Abstract
Mechanosensory transduction underlies the perception of touch, sound and acceleration. The mechanical signals exist in the environment are resensed by the specialized mechanosensory cells, which convert the external forces into the electrical signals. Hearing is a magnificent example that relies on the mechanotransduction mediated by the auditory cells, for example the inner-ear hair cells in vertebrates and the Johnston's organ (JO) in fly. Previous studies have shown the fundamental physiological processes in the fly and vertebrate auditory organs are similar, suggesting that there might be a set of similar molecules underlying these processes. The molecular studies of the fly JO have been shown to be remarkably successful in discovering the developmental and functional genes that provided further implications in vertebrates. Several evolutionarily conserved molecules and signaling pathways have been shown to govern the development of the auditory organs in both vertebrates and invertebrates. The current review describes the similarities and differences between the vertebrate and fly auditory organs at developmental, structural, molecular, and transportation levels.
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Affiliation(s)
- Naveen Prakash Bokolia
- Department of Life Science, National Institute of Technology Rourkela, Rourkela, Orissa, India
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50
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Raft S, Groves AK. Segregating neural and mechanosensory fates in the developing ear: patterning, signaling, and transcriptional control. Cell Tissue Res 2014; 359:315-32. [PMID: 24902666 DOI: 10.1007/s00441-014-1917-6] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2014] [Accepted: 05/08/2014] [Indexed: 12/21/2022]
Abstract
The vertebrate inner ear is composed of multiple sensory receptor epithelia, each of which is specialized for detection of sound, gravity, or angular acceleration. Each receptor epithelium contains mechanosensitive hair cells, which are connected to the brainstem by bipolar sensory neurons. Hair cells and their associated neurons are derived from the embryonic rudiment of the inner ear epithelium, but the precise spatial and temporal patterns of their generation, as well as the signals that coordinate these events, have only recently begun to be understood. Gene expression, lineage tracing, and mutant analyses suggest that both neurons and hair cells are generated from a common domain of neural and sensory competence in the embryonic inner ear rudiment. Members of the Shh, Wnt, and FGF families, together with retinoic acid signals, regulate transcription factor genes within the inner ear rudiment to establish the axial identity of the ear and regionalize neurogenic activity. Close-range signaling, such as that of the Notch pathway, specifies the fate of sensory regions and individual cell types. We also describe positive and negative interactions between basic helix-loop-helix and SoxB family transcription factors that specify either neuronal or sensory fates in a context-dependent manner. Finally, we review recent work on inner ear development in zebrafish, which demonstrates that the relative timing of neurogenesis and sensory epithelial formation is not phylogenetically constrained.
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Affiliation(s)
- Steven Raft
- Section on Sensory Cell Regeneration and Development, National Institute on Deafness and Other Communication Disorders National Institutes of Health, 35 Convent Drive, Bethesda, MD, 20892, USA,
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