1
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Rudolf J, Philipello N, Fleihan T, Dickman JD, Delmore KE. Night-time neuronal activation of Cluster N in a North American songbird. PLoS One 2024; 19:e0300479. [PMID: 38512887 PMCID: PMC10956746 DOI: 10.1371/journal.pone.0300479] [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: 02/06/2023] [Accepted: 02/13/2024] [Indexed: 03/23/2024] Open
Abstract
Night-migrating songbirds utilize the Earth's magnetic field to help navigate to and from their breeding sites each year. A region of the avian forebrain called Cluster N has been shown to be activated during night migratory behavior and it has been implicated in processing geomagnetic information. Previous studies with night-migratory European songbirds have shown that neuronal activity at Cluster N is higher at night than during the day. Comparable work in North American migrants has only been performed in one species of swallows, so extension of examination for Cluster N in other migratory birds is needed. In addition, it is unclear if Cluster N activation is lateralized and the full extent of its boundaries in the forebrain have yet to be described. We used sensory-driven gene expression based on ZENK and the Swainson's thrush, a night-migratory North American songbird, to fill these knowledge gaps. We found elevated levels of gene expression in night- vs. day-active thrushes and no evidence for lateralization in this region. We further examined the anatomical extent of neural activation in the forebrain using 3D reconstruction topology. Our findings demonstrate that Swainson's thrushes possess an extensive bilateral night-activated Cluster N region in the forebrain similar to other European avian species, suggesting that Cluster N is highly conserved in nocturnal migrants.
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Affiliation(s)
- Jennifer Rudolf
- Biology Department, Texas A&M University, College Station, Texas, United States of America
| | - Natalie Philipello
- Biology Department, Texas A&M University, College Station, Texas, United States of America
| | - Tamara Fleihan
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, United States of America
| | - J. David Dickman
- Department of Neuroscience, Baylor College of Medicine, Houston, Texas, United States of America
| | - Kira E. Delmore
- Biology Department, Texas A&M University, College Station, Texas, United States of America
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2
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Fujita T, Aoki N, Mori C, Homma KJ, Yamaguchi S. Molecular biology of serotonergic systems in avian brains. Front Mol Neurosci 2023; 16:1226645. [PMID: 37538316 PMCID: PMC10394247 DOI: 10.3389/fnmol.2023.1226645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 07/05/2023] [Indexed: 08/05/2023] Open
Abstract
Serotonin (5-hydroxytryptamine, 5-HT) is a phylogenetically conserved neurotransmitter and modulator. Neurons utilizing serotonin have been identified in the central nervous systems of all vertebrates. In the central serotonergic system of vertebrate species examined so far, serotonergic neurons have been confirmed to exist in clusters in the brainstem. Although many serotonin-regulated cognitive, behavioral, and emotional functions have been elucidated in mammals, equivalents remain poorly understood in non-mammalian vertebrates. The purpose of this review is to summarize current knowledge of the anatomical organization and molecular features of the avian central serotonergic system. In addition, selected key functions of serotonin are briefly reviewed. Gene association studies between serotonergic system related genes and behaviors in birds have elucidated that the serotonergic system is involved in the regulation of behavior in birds similar to that observed in mammals. The widespread distribution of serotonergic modulation in the central nervous system and the evolutionary conservation of the serotonergic system provide a strong foundation for understanding and comparing the evolutionary continuity of neural circuits controlling corresponding brain functions within vertebrates. The main focus of this review is the chicken brain, with this type of poultry used as a model bird. The chicken is widely used not only as a model for answering questions in developmental biology and as a model for agriculturally useful breeding, but also in research relating to cognitive, behavioral, and emotional processes. In addition to a wealth of prior research on the projection relationships of avian brain regions, detailed subdivision similarities between avian and mammalian brains have recently been identified. Therefore, identifying the neural circuits modulated by the serotonergic system in avian brains may provide an interesting opportunity for detailed comparative studies of the function of serotonergic systems in mammals.
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Affiliation(s)
- Toshiyuki Fujita
- Department of Biological Sciences, Faculty of Pharmaceutical Sciences, Teikyo University, Tokyo, Japan
| | - Naoya Aoki
- Department of Molecular Biology, Faculty of Pharmaceutical Sciences, Teikyo University, Tokyo, Japan
| | - Chihiro Mori
- Department of Molecular Biology, Faculty of Pharmaceutical Sciences, Teikyo University, Tokyo, Japan
| | - Koichi J. Homma
- Department of Molecular Biology, Faculty of Pharmaceutical Sciences, Teikyo University, Tokyo, Japan
| | - Shinji Yamaguchi
- Department of Biological Sciences, Faculty of Pharmaceutical Sciences, Teikyo University, Tokyo, Japan
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3
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Rotov AY, Goriachenkov AA, Cherbunin RV, Firsov ML, Chernetsov N, Astakhova LA. Magnetoreceptory Function of European Robin Retina: Electrophysiological and Morphological Non-Homogeneity. Cells 2022; 11:cells11193056. [PMID: 36231018 PMCID: PMC9564291 DOI: 10.3390/cells11193056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 09/24/2022] [Accepted: 09/26/2022] [Indexed: 11/16/2022] Open
Abstract
The avian magnetic compass allows orientation during migration and is shown to function properly under short-wavelength but not long-wavelength visible light. Therefore, the magnetoreceptive system is assumed to be light- and wavelength-dependent and localized in the retina of the eye. Putative candidates for the role of primary magnetosensory molecules are the cryptochromes that are known to be expressed in the avian retina and must be able to interact with phototransduction proteins. Previously, we reported that in migratory birds change in magnetic field direction induces significant effects on electroretinogram amplitude in response to blue flashes, and such an effect was observed only in the nasal quadrant of the retina. Here, we report new electroretinographic, microscopic and microspectrophotometric data on European robins, confirming the magnetosensitivity of the retinal nasal quadrant after applying the background illumination. We hypothesized that magnetoreceptive distinction of this region may be related to its morphology and analyzed the retinal distribution and optical properties of oil droplets, the filtering structures within cones. We found that the nasal quadrant contains double cones with the most intensely colorized oil droplets compared to the rest of the retina, which may be related to its magnetosensory function.
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Affiliation(s)
- Alexander Yu. Rotov
- Laboratory of Evolution of the Sense Organs, Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223 St. Petersburg, Russia
| | - Arsenii A. Goriachenkov
- Laboratory of Evolution of the Sense Organs, Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223 St. Petersburg, Russia
| | - Roman V. Cherbunin
- Laboratory of Evolution of the Sense Organs, Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223 St. Petersburg, Russia
- Spin Optics Laboratory, Physics Faculty, St. Petersburg State University, 198504 St. Petersburg, Russia
| | - Michael L. Firsov
- Laboratory of Evolution of the Sense Organs, Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223 St. Petersburg, Russia
| | - Nikita Chernetsov
- Laboratory of Evolution of the Sense Organs, Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223 St. Petersburg, Russia
- Department of Vertebrate Zoology, Biological Faculty, St. Petersburg State University, 199034 St. Petersburg, Russia
- Ornithology Lab, Zoological Institute RAS, 199034 St. Petersburg, Russia
| | - Luba A. Astakhova
- Laboratory of Evolution of the Sense Organs, Sechenov Institute of Evolutionary Physiology and Biochemistry RAS, 194223 St. Petersburg, Russia
- Correspondence:
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4
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Morphology, biochemistry and connectivity of Cluster N and the hippocampal formation in a migratory bird. Brain Struct Funct 2022; 227:2731-2749. [DOI: 10.1007/s00429-022-02566-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Accepted: 09/05/2022] [Indexed: 11/02/2022]
Abstract
AbstractThe exceptional navigational capabilities of migrating birds are based on the perception and integration of a variety of natural orientation cues. The “Wulst” in the forebrain of night-migratory songbirds contains a brain area named “Cluster N”, which is involved in processing directional navigational information derived from the Earth´s magnetic field. Cluster N is medially joined by the hippocampal formation, known to retrieve and utilise navigational information. To investigate the connectivity and neurochemical characteristics of Cluster N and the hippocampal formation of migratory birds, we performed morphological and histochemical analyses based on the expression of calbindin, calretinin, parvalbumin, glutamate receptor type 1 and early growth response protein-1 in the night-migratory Garden warbler (Sylvia borin) and mapped their mutual connections using neuronal tract tracing. The resulting expression patterns revealed regionally restricted neurochemical features, which mapped well onto the hippocampal and hyperpallial substructures known from other avian species. Magnetic field-induced neuronal activation covered caudal parts of the hyperpallium and the medially adjacent hippocampal dorsomedial/dorsolateral subdivisions. Neuronal tract tracings revealed connections between Cluster N and the hippocampal formation with the vast majority originating from the densocellular hyperpallium, either directly or indirectly via the area corticoidea dorsolateralis. Our data indicate that the densocellular hyperpallium could represent a central relay for the transmission of magnetic compass information to the hippocampal formation where it might be integrated with other navigational cues in night-migratory songbirds.
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5
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Broadband 75-85 MHz radiofrequency fields disrupt magnetic compass orientation in night-migratory songbirds consistent with a flavin-based radical pair magnetoreceptor. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2022; 208:97-106. [PMID: 35019998 PMCID: PMC8918455 DOI: 10.1007/s00359-021-01537-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 12/15/2021] [Accepted: 12/17/2021] [Indexed: 12/20/2022]
Abstract
The light-dependent magnetic compass sense of night-migratory songbirds can be disrupted by weak radiofrequency fields. This finding supports a quantum mechanical, radical-pair-based mechanism of magnetoreception as observed for isolated cryptochrome 4, a protein found in birds’ retinas. The exact identity of the magnetically sensitive radicals in cryptochrome is uncertain in vivo, but their formation seems to require a bound flavin adenine dinucleotide chromophore and a chain of four tryptophan residues within the protein. Resulting from the hyperfine interactions of nuclear spins with the unpaired electrons, the sensitivity of the radicals to radiofrequency magnetic fields depends strongly on the number of magnetic nuclei (hydrogen and nitrogen atoms) they contain. Quantum-chemical calculations suggested that electromagnetic noise in the frequency range 75–85 MHz could give information about the identity of the radicals involved. Here, we show that broadband 75–85 MHz radiofrequency fields prevent a night-migratory songbird from using its magnetic compass in behavioural experiments. These results indicate that at least one of the components of the radical pair involved in the sensory process of avian magnetoreception must contain a substantial number of strong hyperfine interactions as would be the case if a flavin–tryptophan radical pair were the magnetic sensor.
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6
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Wong SY, Wei Y, Mouritsen H, Solov'yov IA, Hore PJ. Cryptochrome magnetoreception: four tryptophans could be better than three. J R Soc Interface 2021; 18:20210601. [PMID: 34753309 PMCID: PMC8580466 DOI: 10.1098/rsif.2021.0601] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Accepted: 10/14/2021] [Indexed: 12/28/2022] Open
Abstract
The biophysical mechanism of the magnetic compass sensor in migratory songbirds is thought to involve photo-induced radical pairs formed in cryptochrome (Cry) flavoproteins located in photoreceptor cells in the eyes. In Cry4a-the most likely of the six known avian Crys to have a magnetic sensing function-four radical pair states are formed sequentially by the stepwise transfer of an electron along a chain of four tryptophan residues to the photo-excited flavin. In purified Cry4a from the migratory European robin, the third of these flavin-tryptophan radical pairs is more magnetically sensitive than the fourth, consistent with the smaller separation of the radicals in the former. Here, we explore the idea that these two radical pair states of Cry4a could exist in rapid dynamic equilibrium such that the key magnetic and kinetic properties are weighted averages. Spin dynamics simulations suggest that the third radical pair is largely responsible for magnetic sensing while the fourth may be better placed to initiate magnetic signalling particularly if the terminal tryptophan radical can be reduced by a nearby tyrosine. Such an arrangement could have allowed independent optimization of the essential sensing and signalling functions of the protein. It might also rationalize why avian Cry4a has four tryptophans while Crys from plants have only three.
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Affiliation(s)
- Siu Ying Wong
- Institut für Physik, Carl-von-Ossietzky Universität Oldenburg, Oldenburg 26111, Germany
| | - Yujing Wei
- Department of Chemistry, University of Oxford, Oxford OX1 3QZ, UK
| | - Henrik Mouritsen
- Institut für Biologie und Umweltwissenschaften, Carl-von-Ossietzky Universität Oldenburg, Oldenburg 26111, Germany
- Research Centre for Neurosensory Science, University of Oldenburg, Oldenburg 26111, Germany
| | - Ilia A. Solov'yov
- Institut für Physik, Carl-von-Ossietzky Universität Oldenburg, Oldenburg 26111, Germany
| | - P. J. Hore
- Department of Chemistry, University of Oxford, Oxford OX1 3QZ, UK
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7
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Einwich A, Seth PK, Bartölke R, Bolte P, Feederle R, Dedek K, Mouritsen H. Localisation of cryptochrome 2 in the avian retina. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2021; 208:69-81. [PMID: 34677638 PMCID: PMC8918457 DOI: 10.1007/s00359-021-01506-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 08/13/2021] [Accepted: 08/19/2021] [Indexed: 12/12/2022]
Abstract
Cryptochromes are photolyase-related blue-light receptors acting as core components of the mammalian circadian clock in the cell nuclei. One or more members of the cryptochrome protein family are also assumed to play a role in avian magnetoreception, but the primary sensory molecule in the retina of migratory birds that mediates light-dependent magnetic compass orientation has still not been identified. The mRNA of cryptochrome 2 (Cry2) has been reported to be located in the cell nuclei of the retina, but Cry2 localisation has not yet been demonstrated at the protein level. Here, we provide evidence that Cry2 protein is located in the photoreceptor inner segments, the outer nuclear layer, the inner nuclear layer and the ganglion cell layer in the retina of night-migratory European robins, homing pigeons and domestic chickens. At the subcellular level, we find Cry2 both in the cytoplasm and the nucleus of cells residing in these layers. This broad nucleic expression rather points to a role for avian Cry2 in the circadian clock and is consistent with a function as a transcription factor, analogous to mammalian Cry2, and speaks against an involvement in magnetoreception.
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Affiliation(s)
- Angelika Einwich
- Institute for Biology and Environmental Sciences, Carl von Ossietzky University Oldenburg, Oldenburg, Germany
| | - Pranav Kumar Seth
- Institute for Biology and Environmental Sciences, Carl von Ossietzky University Oldenburg, Oldenburg, Germany
| | - Rabea Bartölke
- Institute for Biology and Environmental Sciences, Carl von Ossietzky University Oldenburg, Oldenburg, Germany
| | - Petra Bolte
- Institute for Biology and Environmental Sciences, Carl von Ossietzky University Oldenburg, Oldenburg, Germany
| | - Regina Feederle
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute for Diabetes and Obesity, Monoclonal Antibody Core Facility, Neuherberg, Germany
| | - Karin Dedek
- Institute for Biology and Environmental Sciences, Carl von Ossietzky University Oldenburg, Oldenburg, Germany.,Research Centre for Neurosensory Sciences, Carl von Ossietzky University Oldenburg, Oldenburg, Germany
| | - Henrik Mouritsen
- Institute for Biology and Environmental Sciences, Carl von Ossietzky University Oldenburg, Oldenburg, Germany. .,Research Centre for Neurosensory Sciences, Carl von Ossietzky University Oldenburg, Oldenburg, Germany.
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8
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Biegler MT, Cantin LJ, Scarano DL, Jarvis ED. Controlling for activity-dependent genes and behavioral states is critical for determining brain relationships within and across species. J Comp Neurol 2021; 529:3206-3221. [PMID: 33855704 PMCID: PMC8205984 DOI: 10.1002/cne.25157] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 03/16/2021] [Accepted: 03/19/2021] [Indexed: 12/16/2022]
Abstract
The genetic profile of vertebrate pallia has long driven debate on homology across distantly related clades. Based on an expression profile of the orphan nuclear receptor NR4A2 in mouse and chicken brains, Puelles et al. (The Journal of Comparative Neurology, 2016, 524, 665–703) concluded that the avian lateral mesopallium is homologous to the mammalian claustrum, and the medial mesopallium homologous to the insula cortex. They argued that their findings contradict conclusions by Jarvis et al. (The Journal of Comparative Neurology, 2013, 521, 3614–3665) and Chen et al. (The Journal of Comparative Neurology, 2013, 521, 3666–3701) that the hyperpallium densocellare is instead a mesopallium cell population, and by Suzuki and Hirata (Frontiers in Neuroanatomy, 2014, 8, 783) that the avian mesopallium is homologous to mammalian cortical layers 2/3. Here, we find that NR4A2 is an activity‐dependent gene and cannot be used to determine brain organization or species relationships without considering behavioral state. Activity‐dependent NR4A2 expression has been previously demonstrated in the rodent brain, with the highest induction occurring within the claustrum, amygdala, deep and superficial cortical layers, and hippocampus. In the zebra finch, we find that NR4A2 is constitutively expressed in the arcopallium, but induced in parts of the mesopallium, and in sparse cells within the hyperpallium, depending on animal stimulus or behavioral state. Basal and induced NR4A2 expression patterns do not discount the previously named avian hyperpallium densocellare as dorsal mesopallium and conflict with proposed homology between the avian mesopallium and mammalian claustrum/insula at the exclusion of other brain regions. Broadly, these findings highlight the importance of controlling for behavioral state and neural activity to genetically define brain cell population relationships within and across species.
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Affiliation(s)
- Matthew T Biegler
- Department of Neurobiology, Duke University Medical Center, Durham, North Carolina, USA.,Laboratory of Neurogenetics of Language, The Rockefeller University, New York, New York, USA
| | - Lindsey J Cantin
- Laboratory of Neurogenetics of Language, The Rockefeller University, New York, New York, USA
| | - Danielle L Scarano
- Department of Neurobiology, Duke University Medical Center, Durham, North Carolina, USA
| | - Erich D Jarvis
- Department of Neurobiology, Duke University Medical Center, Durham, North Carolina, USA.,Laboratory of Neurogenetics of Language, The Rockefeller University, New York, New York, USA.,Howard Hughes Medical Institute, Chevy Chase, Maryland, USA
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9
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Bolte P, Einwich A, Seth PK, Chetverikova R, Heyers D, Wojahn I, Janssen-Bienhold U, Feederle R, Hore P, Dedek K, Mouritsen H. Cryptochrome 1a localisation in light- and dark-adapted retinae of several migratory and non-migratory bird species: no signs of light-dependent activation. ETHOL ECOL EVOL 2021. [DOI: 10.1080/03949370.2020.1870571] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
- Petra Bolte
- Institute for Biology and Environmental Sciences, Carl-von-Ossietzky-University Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129 Oldenburg, Germany
| | - Angelika Einwich
- Institute for Biology and Environmental Sciences, Carl-von-Ossietzky-University Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129 Oldenburg, Germany
| | - Pranav K. Seth
- Institute for Biology and Environmental Sciences, Carl-von-Ossietzky-University Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129 Oldenburg, Germany
| | - Raisa Chetverikova
- Institute for Biology and Environmental Sciences, Carl-von-Ossietzky-University Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129 Oldenburg, Germany
| | - Dominik Heyers
- Institute for Biology and Environmental Sciences, Carl-von-Ossietzky-University Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129 Oldenburg, Germany
- Research Centre for Neurosensory Sciences, Carl-von-Ossietzky-University Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129 Oldenburg, Germany
| | - Irina Wojahn
- Institute for Biology and Environmental Sciences, Carl-von-Ossietzky-University Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129 Oldenburg, Germany
| | - Ulrike Janssen-Bienhold
- Research Centre for Neurosensory Sciences, Carl-von-Ossietzky-University Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129 Oldenburg, Germany
- Department of Neuroscience, Carl-von-Ossietzky-University Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129 Oldenburg, Germany
| | - Regina Feederle
- Institute for Diabetes and Obesity, Monoclonal Antibody Core Facility, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - Peter Hore
- Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QZ, United Kingdom
| | - Karin Dedek
- Institute for Biology and Environmental Sciences, Carl-von-Ossietzky-University Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129 Oldenburg, Germany
- Research Centre for Neurosensory Sciences, Carl-von-Ossietzky-University Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129 Oldenburg, Germany
| | - Henrik Mouritsen
- Institute for Biology and Environmental Sciences, Carl-von-Ossietzky-University Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129 Oldenburg, Germany
- Research Centre for Neurosensory Sciences, Carl-von-Ossietzky-University Oldenburg, Carl-von-Ossietzky-Straße 9-11, 26129 Oldenburg, Germany
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10
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Bingman VP, Pemberton ML, Mora CV. Avian forebrain processing of magnetic intensity and inclination: hippocampus, anterior forebrain Wulst and an unexpected double-dissociation. ETHOL ECOL EVOL 2021. [DOI: 10.1080/03949370.2021.1871966] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- Verner P. Bingman
- Department of Psychology and J.P. Scott Center for Neuroscience, Mind and Behavior, Bowling Green State University, Bowling Green, Ohio 43403, USA
| | - Merissa L. Pemberton
- Department of Psychology and J.P. Scott Center for Neuroscience, Mind and Behavior, Bowling Green State University, Bowling Green, Ohio 43403, USA
| | - Cordula V. Mora
- Department of Psychology and J.P. Scott Center for Neuroscience, Mind and Behavior, Bowling Green State University, Bowling Green, Ohio 43403, USA
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11
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Einwich A, Dedek K, Seth PK, Laubinger S, Mouritsen H. A novel isoform of cryptochrome 4 (Cry4b) is expressed in the retina of a night-migratory songbird. Sci Rep 2020; 10:15794. [PMID: 32978454 PMCID: PMC7519125 DOI: 10.1038/s41598-020-72579-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 07/28/2020] [Indexed: 01/22/2023] Open
Abstract
The primary sensory molecule underlying light-dependent magnetic compass orientation in migratory birds has still not been identified. The cryptochromes are the only known class of vertebrate proteins which could mediate this mechanism in the avian retina. Cryptochrome 4 of the night-migratory songbird the European robin (Erithacus rubecula; erCry4) has several of the properties needed to be the primary magnetoreceptor in the avian eye. Here, we report on the identification of a novel isoform of erCry4, which we named erCry4b. Cry4b includes an additional exon of 29 amino acids compared to the previously described form of Cry4, now called Cry4a. When comparing the retinal circadian mRNA expression pattern of the already known isoform erCry4a and the novel erCry4b isoform, we find that erCry4a is stably expressed throughout day and night, whereas erCry4b shows a diurnal mRNA oscillation. The differential characteristics of the two erCry4 isoforms regarding their 24-h rhythmicity in mRNA expression leads us to suggest that they might have different functions. Based on the 24-h expression pattern, erCry4a remains the more likely cryptochrome to be involved in radical-pair-based magnetoreception, but at the present time, an involvement of erCry4b cannot be excluded.
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Affiliation(s)
- Angelika Einwich
- Institute for Biology and Environmental Sciences, Neurosensorics/Animal Navigation, Carl-von-Ossietzky-Universität Oldenburg, Oldenburg, Germany.,Research Centre for Neurosensory Sciences, Carl-von-Ossietzky-Universität Oldenburg, Oldenburg, Germany
| | - Karin Dedek
- Institute for Biology and Environmental Sciences, Neurosensorics/Animal Navigation, Carl-von-Ossietzky-Universität Oldenburg, Oldenburg, Germany.,Research Centre for Neurosensory Sciences, Carl-von-Ossietzky-Universität Oldenburg, Oldenburg, Germany
| | - Pranav Kumar Seth
- Institute for Biology and Environmental Sciences, Neurosensorics/Animal Navigation, Carl-von-Ossietzky-Universität Oldenburg, Oldenburg, Germany.,Research Centre for Neurosensory Sciences, Carl-von-Ossietzky-Universität Oldenburg, Oldenburg, Germany
| | - Sascha Laubinger
- Institute for Biology and Environmental Sciences, Evolutionäre Genetik der Pflanzen, Carl-von-Ossietzky-Universität Oldenburg, Oldenburg, Germany
| | - Henrik Mouritsen
- Institute for Biology and Environmental Sciences, Neurosensorics/Animal Navigation, Carl-von-Ossietzky-Universität Oldenburg, Oldenburg, Germany. .,Research Centre for Neurosensory Sciences, Carl-von-Ossietzky-Universität Oldenburg, Oldenburg, Germany.
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12
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Wu H, Scholten A, Einwich A, Mouritsen H, Koch KW. Protein-protein interaction of the putative magnetoreceptor cryptochrome 4 expressed in the avian retina. Sci Rep 2020; 10:7364. [PMID: 32355203 PMCID: PMC7193638 DOI: 10.1038/s41598-020-64429-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2019] [Accepted: 04/16/2020] [Indexed: 11/15/2022] Open
Abstract
Migratory birds can sense the Earth’s magnetic field and use it for orientation over thousands of kilometres. A light-dependent radical-pair mechanism associated with the visual system is currently discussed as the underlying mechanism of the magnetic compass sense. The blue light receptor cryptochrome 4 (Cry4) is considered as the most likely primary sensory protein that detects the geomagnetic field. Since the protein interaction partners of Cry4 are completely unknown at present, here, we aim to identify potential candidate interaction partners of Cry4 in the avian retina. We used the yeast-two-hybrid system to screen avian cDNA libraries for possible interaction partners of Cry4 in the European robin. The UAS-GAL yeast two hybrid system was applied to confirm a group of candidate Cry4 interaction partners. Six proteins were found to be particularly promising candidates for interacting with European robin Cry4. The identified genes code for guanine nucleotide-binding protein G(t) subunit alpha-2 (GNAT2), long-wavelength-sensitive opsin (LWS, also called iodopsin), guanine nucleotide-binding protein subunit gamma 10 (GNG10), potassium voltage-gated channel subfamily V member 2 (KCNV2), retinol binding protein 1 (RBP1) and retinal G protein-coupled receptor (RGR). All genes are known to be expressed in vertebrate retinae of different species. We conclude by discussing putative signalling pathways that could connect cryptochrome 4 to one or more of these 6 candidates.
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Affiliation(s)
- Haijia Wu
- Department of Neuroscience, Division of Biochemistry, University of Oldenburg, D-26111, Oldenburg, Germany
| | - Alexander Scholten
- Department of Neuroscience, Division of Biochemistry, University of Oldenburg, D-26111, Oldenburg, Germany
| | - Angelika Einwich
- Department of Biology and Environmental Sciences, Neurosensorics/Animal Navigation, University of Oldenburg, D-26111, Oldenburg, Germany
| | - Henrik Mouritsen
- Department of Biology and Environmental Sciences, Neurosensorics/Animal Navigation, University of Oldenburg, D-26111, Oldenburg, Germany.,Research Center for Neurosensory Sciences, University of Oldenburg, 26111, Oldenburg, Germany
| | - Karl-Wilhelm Koch
- Department of Neuroscience, Division of Biochemistry, University of Oldenburg, D-26111, Oldenburg, Germany. .,Research Center for Neurosensory Sciences, University of Oldenburg, 26111, Oldenburg, Germany.
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13
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Discrimination of artificial starry sky by pigeons. Learn Behav 2020; 48:22-26. [PMID: 32043269 DOI: 10.3758/s13420-020-00420-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Night migratory birds use the star compass for their navigation. Here, I examined discrimination of a starry sky by a nonmigratory bird, the pigeon. Four pigeons were trained in an operant chamber to discriminate between an artificial starry sky created using software (Stella Theater Pro) and a black sky without stars. After they learned the task, they received three generalization tests. Test 1 presented a starry sky with different classes of stars (i.e., the number of stars was changed). Test 2 presented a starry sky at different times (i.e., a horizontal shift of the sky). Test 3 presented a starry sky at different latitudes (i.e., a vertical shift of the sky). The pigeons displayed a clear generalization gradient with a peak shift to the sky with more stars in Test 1 and a peak close to the original sky in Test 3, but almost a flat gradient in Test 2. Therefore, pigeons demonstrated stimulus control using the pattern of the stars, and they were more sensitive to the vertical shift than to the horizontal shift.
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14
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Kobylkov D, Wynn J, Winklhofer M, Chetverikova R, Xu J, Hiscock H, Hore PJ, Mouritsen H. Electromagnetic 0.1-100 kHz noise does not disrupt orientation in a night-migrating songbird implying a spin coherence lifetime of less than 10 µs. J R Soc Interface 2019; 16:20190716. [PMID: 31847760 DOI: 10.1098/rsif.2019.0716] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
According to the currently prevailing theory, the magnetic compass sense in night-migrating birds relies on a light-dependent radical-pair-based mechanism. It has been shown that radio waves at megahertz frequencies disrupt magnetic orientation in migratory birds, providing evidence for a quantum-mechanical origin of the magnetic compass. Still, many crucial properties, e.g. the lifetime of the proposed magnetically sensitive radical pair, remain unknown. The current study aims to estimate the spin coherence time of the radical pair, based on the behavioural responses of migratory birds to broadband electromagnetic fields covering the frequency band 0.1-100 kHz. A finding that the birds were unable to use their magnetic compass under these conditions would imply surprisingly long-lived (greater than 10 µs) spin coherence. However, we observed no effect of 0.1-100 kHz radiofrequency (RF) fields on the orientation of night-migratory Eurasian blackcaps (Sylvia atricapilla). This suggests that the lifetime of the spin coherence involved in magnetoreception is shorter than the period of the highest frequency RF fields used in this experiment (i.e. approx. 10 µs). This result, in combination with an earlier study showing that 20-450 kHz electromagnetic fields disrupt magnetic compass orientation, suggests that the spin coherence lifetime of the magnetically sensitive radical pair is in the range 2-10 µs.
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Affiliation(s)
- Dmitry Kobylkov
- AG 'Neurosensorik', University Oldenburg, 26111 Oldenburg, Germany.,Research Centre for Neurosensory Sciences, University Oldenburg, 26111 Oldenburg, Germany
| | - Joe Wynn
- Oxford Navigation Group, Department of Zoology, University of Oxford, Oxford, UK
| | - Michael Winklhofer
- AG 'Neurosensorik', University Oldenburg, 26111 Oldenburg, Germany.,AG 'Sensory Biology of Animals', University Oldenburg, 26111 Oldenburg, Germany
| | - Raisa Chetverikova
- AG 'Neurosensorik', University Oldenburg, 26111 Oldenburg, Germany.,Research Centre for Neurosensory Sciences, University Oldenburg, 26111 Oldenburg, Germany
| | - Jingjing Xu
- AG 'Neurosensorik', University Oldenburg, 26111 Oldenburg, Germany.,Research Centre for Neurosensory Sciences, University Oldenburg, 26111 Oldenburg, Germany
| | - Hamish Hiscock
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, Oxford, UK
| | - P J Hore
- Physical and Theoretical Chemistry Laboratory, Department of Chemistry, University of Oxford, Oxford, UK
| | - Henrik Mouritsen
- AG 'Neurosensorik', University Oldenburg, 26111 Oldenburg, Germany.,Research Centre for Neurosensory Sciences, University Oldenburg, 26111 Oldenburg, Germany
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15
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Navigating at night: fundamental limits on the sensitivity of radical pair magnetoreception under dim light. Q Rev Biophys 2019; 52:e9. [DOI: 10.1017/s0033583519000076] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Abstract
Night-migratory songbirds appear to sense the direction of the Earth's magnetic field via radical pair intermediates formed photochemically in cryptochrome flavoproteins contained in photoreceptor cells in their retinas. It is an open question whether this light-dependent mechanism could be sufficiently sensitive given the low-light levels experienced by nocturnal migrants. The scarcity of available photons results in significant uncertainty in the signal generated by the magnetoreceptors distributed around the retina. Here we use results from Information Theory to obtain a lower bound estimate of the precision with which a bird could orient itself using only geomagnetic cues. Our approach bypasses the current lack of knowledge about magnetic signal transduction and processing in vivo by computing the best-case compass precision under conditions where photons are in short supply. We use this method to assess the performance of three plausible cryptochrome-derived flavin-containing radical pairs as potential magnetoreceptors.
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16
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Abstract
Birds can use two kinds of information from the geomagnetic field for navigation: the direction of the field lines as a compass and probably magnetic intensity as a component of the navigational ‘map’. The direction of the magnetic field appears to be sensed via radical pair processes in the eyes, with the crucial radical pairs formed by cryptochrome. It is transmitted by the optic nerve to the brain, where parts of the visual system seem to process the respective information. Magnetic intensity appears to be perceived by magnetite-based receptors in the beak region; the information is transmitted by the ophthalmic branch of the trigeminal nerve to the trigeminal ganglion and the trigeminal brainstem nuclei. Yet in spite of considerable progress in recent years, many details are still unclear, among them details of the radical pair processes and their transformation into a nervous signal, the precise location of the magnetite-based receptors and the centres in the brain where magnetic information is combined with other navigational information for the navigational processes.
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Affiliation(s)
- Roswitha Wiltschko
- FB Biowissenschaften, Goethe-Universität Frankfurt, Frankfurt am Main, Germany
| | - Wolfgang Wiltschko
- FB Biowissenschaften, Goethe-Universität Frankfurt, Frankfurt am Main, Germany
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17
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Agarwal N, Komal R, Kumari Y, Malik S, Rani S, Kumar V. Development of vernal migration in redheaded buntings: concurrent behavioral, physiological and neural changes under stimulatory photoperiods. Photochem Photobiol Sci 2019; 18:2509-2520. [DOI: 10.1039/c9pp00273a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
We investigated changes in behavior, physiology and selected brain regions during the development of vernal migration and reproduction phenotypes in migratory redheaded buntings.
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Affiliation(s)
- Neha Agarwal
- Department of Zoology
- University of Delhi
- Delhi 110007
- India
- Department of Zoology
| | - Ruchi Komal
- Department of Zoology
- University of Lucknow
- Lucknow
- India
| | | | - Shalie Malik
- Department of Zoology
- University of Lucknow
- Lucknow
- India
| | - Sangeeta Rani
- Department of Zoology
- University of Lucknow
- Lucknow
- India
| | - Vinod Kumar
- Department of Zoology
- University of Delhi
- Delhi 110007
- India
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18
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Long-distance navigation and magnetoreception in migratory animals. Nature 2018; 558:50-59. [PMID: 29875486 DOI: 10.1038/s41586-018-0176-1] [Citation(s) in RCA: 226] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2017] [Accepted: 04/13/2018] [Indexed: 11/08/2022]
Abstract
For centuries, humans have been fascinated by how migratory animals find their way over thousands of kilometres. Here, I review the mechanisms used in animal orientation and navigation with a particular focus on long-distance migrants and magnetoreception. I contend that any long-distance navigational task consists of three phases and that no single cue or mechanism will enable animals to navigate with pinpoint accuracy over thousands of kilometres. Multiscale and multisensory cue integration in the brain is needed. I conclude by raising twenty important mechanistic questions related to long-distance animal navigation that should be solved over the next twenty years.
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19
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Pakhomov A, Bojarinova J, Cherbunin R, Chetverikova R, Grigoryev PS, Kavokin K, Kobylkov D, Lubkovskaja R, Chernetsov N. Very weak oscillating magnetic field disrupts the magnetic compass of songbird migrants. J R Soc Interface 2017; 14:20170364. [PMID: 28794163 PMCID: PMC5582129 DOI: 10.1098/rsif.2017.0364] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 07/13/2017] [Indexed: 11/12/2022] Open
Abstract
Previously, it has been shown that long-distance migrants, garden warblers (Sylvia borin), were disoriented in the presence of narrow-band oscillating magnetic field (1.403 MHz OMF, 190 nT) during autumn migration. This agrees with the data of previous experiments with European robins (Erithacus rubecula). In this study, we report the results of experiments with garden warblers tested under a 1.403 MHz OMF with various amplitudes (∼0.4, 1, ∼2.4, 7 and 20 nT). We found that the ability of garden warblers to orient in round arenas using the magnetic compass could be disrupted by a very weak oscillating field, such as an approximate 2.4, 7 and 20 nT OMF, but not by an OMF with an approximate 0.4 nT amplitude. The results of the present study indicate that the sensitivity threshold of the magnetic compass to the OMF lies around 2-3 nT, while in experiments with European robins the birds were disoriented in a 15 nT OMF but could choose the appropriate migratory direction when a 5 nT OMF was added to the stationary magnetic field. The radical-pair model, one of the mainstream theories of avian magnetoreception, cannot explain the sensitivity to such a low-intensity OMF, and therefore, it needs further refinement.
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Affiliation(s)
- Alexander Pakhomov
- Biological Station Rybachy, Zoological Institute RAS, 238535 Rybachy, Kaliningrad Region, Russia
- Sechenov Institute of Evolutionary Physiology and Biochemistry, 44 Thorez Ave, 194223 St Petersburg, Russia
| | - Julia Bojarinova
- Sechenov Institute of Evolutionary Physiology and Biochemistry, 44 Thorez Ave, 194223 St Petersburg, Russia
- St Petersburg State University, 7-9 Universitetskaya Emb., St Petersburg 199034, Russia
| | - Roman Cherbunin
- Sechenov Institute of Evolutionary Physiology and Biochemistry, 44 Thorez Ave, 194223 St Petersburg, Russia
- St Petersburg State University, 7-9 Universitetskaya Emb., St Petersburg 199034, Russia
| | - Raisa Chetverikova
- St Petersburg State University, 7-9 Universitetskaya Emb., St Petersburg 199034, Russia
- AG Neurosensorik (Animal Navigation), Institut für Biologie und Umweltwissenschaften (IBU), University of Oldenburg, 26111 Oldenburg, Germany
| | - Philipp S Grigoryev
- St Petersburg State University, 7-9 Universitetskaya Emb., St Petersburg 199034, Russia
| | - Kirill Kavokin
- Sechenov Institute of Evolutionary Physiology and Biochemistry, 44 Thorez Ave, 194223 St Petersburg, Russia
- St Petersburg State University, 7-9 Universitetskaya Emb., St Petersburg 199034, Russia
- A.F. Ioffe Physical Technical Institute, 26 Polytechnicheskaya, St Petersburg 194021, Russia
| | - Dmitry Kobylkov
- AG Neurosensorik (Animal Navigation), Institut für Biologie und Umweltwissenschaften (IBU), University of Oldenburg, 26111 Oldenburg, Germany
| | - Regina Lubkovskaja
- St Petersburg State University, 7-9 Universitetskaya Emb., St Petersburg 199034, Russia
| | - Nikita Chernetsov
- Biological Station Rybachy, Zoological Institute RAS, 238535 Rybachy, Kaliningrad Region, Russia
- Sechenov Institute of Evolutionary Physiology and Biochemistry, 44 Thorez Ave, 194223 St Petersburg, Russia
- St Petersburg State University, 7-9 Universitetskaya Emb., St Petersburg 199034, Russia
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20
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Lateralization of the Avian Magnetic Compass: Analysis of Its Early Plasticity. Symmetry (Basel) 2017. [DOI: 10.3390/sym9050077] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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21
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Heyers D, Elbers D, Bulte M, Bairlein F, Mouritsen H. The magnetic map sense and its use in fine-tuning the migration programme of birds. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2017; 203:491-497. [PMID: 28365788 DOI: 10.1007/s00359-017-1164-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 03/06/2017] [Accepted: 03/07/2017] [Indexed: 10/19/2022]
Abstract
The Earth's magnetic field is one of several natural cues, which migratory birds can use to derive directional ("compass") information for orientation on their biannual migratory journeys. Moreover, magnetic field effects on prominent aspects of the migratory programme of birds, such as migratory restlessness behaviour, fuel deposition and directional orientation, implicate that geomagnetic information can also be used to derive positional ("map") information. While the magnetic "compass" in migratory birds is likely to be based on radical pair-forming molecules embedded in their visual system, the sensory correlates underlying a magnetic "map" sense currently remain elusive. Behavioural, physiological and neurobiological findings indicate that the sensor is most likely innervated by the ophthalmic branch of the trigeminal nerve and based on magnetic iron particles. Information from this unknown sensor is neither necessary nor sufficient for a functional magnetic compass, but instead could contribute important components of a multifactorial "map" for global positioning. Positional information could allow migratory birds to make vitally important dynamic adaptations of their migratory programme at any relevant point during their journeys.
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Affiliation(s)
- D Heyers
- AG Animal Navigation, Faculty of Biology/Environmental Sciences, University of Oldenburg, 26111, Oldenburg, Germany. .,Research Centre for Neurosensory Sciences, University of Oldenburg, 26111, Oldenburg, Germany.
| | - D Elbers
- AG Animal Navigation, Faculty of Biology/Environmental Sciences, University of Oldenburg, 26111, Oldenburg, Germany.,Research Centre for Neurosensory Sciences, University of Oldenburg, 26111, Oldenburg, Germany.,AG Biochemistry, Faculty of Medicine/Health Sciences, University of Oldenburg, 26111, Oldenburg, Germany
| | - M Bulte
- , Schmidtkunzstraße 13, 86199, Augsburg, Germany.,Institute for Avian Research "Vogelwarte Helgoland", 26386, Wilhelmshaven, Germany
| | - F Bairlein
- Institute for Avian Research "Vogelwarte Helgoland", 26386, Wilhelmshaven, Germany
| | - H Mouritsen
- AG Animal Navigation, Faculty of Biology/Environmental Sciences, University of Oldenburg, 26111, Oldenburg, Germany.,Research Centre for Neurosensory Sciences, University of Oldenburg, 26111, Oldenburg, Germany
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22
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Magnetic activation in the brain of the migratory northern wheatear (Oenanthe oenanthe). J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2017; 203:591-600. [DOI: 10.1007/s00359-017-1167-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 03/16/2017] [Accepted: 03/19/2017] [Indexed: 10/19/2022]
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23
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Compass systems. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2017; 203:447-453. [DOI: 10.1007/s00359-016-1140-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2016] [Revised: 12/04/2016] [Accepted: 12/12/2016] [Indexed: 11/26/2022]
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24
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Affiliation(s)
- P. J. Hore
- Department of Chemistry, University of Oxford, Oxford OX1 3QZ, United Kingdom;
| | - Henrik Mouritsen
- Institut für Biologie und Umweltwissenschaften, Carl von Ossietzky Universität Oldenburg, DE-26111 Oldenburg, Germany;
- Research Centre for Neurosensory Sciences, University of Oldenburg, DE-26111 Oldenburg, Germany
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25
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Bolte P, Bleibaum F, Einwich A, Günther A, Liedvogel M, Heyers D, Depping A, Wöhlbrand L, Rabus R, Janssen‐Bienhold U, Mouritsen H. Localisation of the Putative Magnetoreceptive Protein Cryptochrome 1b in the Retinae of Migratory Birds and Homing Pigeons. PLoS One 2016; 11:e0147819. [PMID: 26953791 PMCID: PMC4783096 DOI: 10.1371/journal.pone.0147819] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2015] [Accepted: 01/08/2016] [Indexed: 01/24/2023] Open
Abstract
Cryptochromes are ubiquitously expressed in various animal tissues including the retina. Some cryptochromes are involved in regulating circadian activity. Cryptochrome proteins have also been suggested to mediate the primary mechanism in light-dependent magnetic compass orientation in birds. Cryptochrome 1b (Cry1b) exhibits a unique carboxy terminus exclusively found in birds so far, which might be indicative for a specialised function. Cryptochrome 1a (Cry1a) is so far the only cryptochrome protein that has been localised to specific cell types within the retina of migratory birds. Here we show that Cry1b, an alternative splice variant of Cry1a, is also expressed in the retina of migratory birds, but it is primarily located in other cell types than Cry1a. This could suggest different functions for the two splice products. Using diagnostic bird-specific antibodies (that allow for a precise discrimination between both proteins), we show that Cry1b protein is found in the retinae of migratory European robins (Erithacus rubecula), migratory Northern Wheatears (Oenanthe oenanthe) and pigeons (Columba livia). In all three species, retinal Cry1b is localised in cell types which have been discussed as potentially well suited locations for magnetoreception: Cry1b is observed in the cytosol of ganglion cells, displaced ganglion cells, and in photoreceptor inner segments. The cytosolic rather than nucleic location of Cry1b in the retina reported here speaks against a circadian clock regulatory function of Cry1b and it allows for the possible involvement of Cry1b in a radical-pair-based magnetoreception mechanism.
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Affiliation(s)
- Petra Bolte
- Institute for Biology and Environmental Sciences, University of Oldenburg, Oldenburg, Germany
- Research Centre for Neurosensory Sciences, University of Oldenburg, Oldenburg, Germany
| | - Florian Bleibaum
- Institute for Biology and Environmental Sciences, University of Oldenburg, Oldenburg, Germany
- Research Centre for Neurosensory Sciences, University of Oldenburg, Oldenburg, Germany
| | - Angelika Einwich
- Institute for Biology and Environmental Sciences, University of Oldenburg, Oldenburg, Germany
- Research Centre for Neurosensory Sciences, University of Oldenburg, Oldenburg, Germany
| | - Anja Günther
- Institute for Biology and Environmental Sciences, University of Oldenburg, Oldenburg, Germany
- Research Centre for Neurosensory Sciences, University of Oldenburg, Oldenburg, Germany
| | | | - Dominik Heyers
- Institute for Biology and Environmental Sciences, University of Oldenburg, Oldenburg, Germany
- Research Centre for Neurosensory Sciences, University of Oldenburg, Oldenburg, Germany
| | - Anne Depping
- Institute for Biology and Environmental Sciences, University of Oldenburg, Oldenburg, Germany
- Research Centre for Neurosensory Sciences, University of Oldenburg, Oldenburg, Germany
| | - Lars Wöhlbrand
- Institute for Chemistry and Biology of the Marine Environment, Carl-von-Ossietzky University, Oldenburg, Germany
| | - Ralf Rabus
- Institute for Chemistry and Biology of the Marine Environment, Carl-von-Ossietzky University, Oldenburg, Germany
| | | | - Henrik Mouritsen
- Institute for Biology and Environmental Sciences, University of Oldenburg, Oldenburg, Germany
- Research Centre for Neurosensory Sciences, University of Oldenburg, Oldenburg, Germany
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26
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Affiliation(s)
- Henrik Mouritsen
- Institut für Biologie und Umweltwissenschaften, Carl-von-Ossietzky-Universität Oldenburg, D-26111 Oldenburg, Germany; ,
- Research Center Neurosensory Sciences, University of Oldenburg, D-26111 Oldenburg, Germany
| | - Dominik Heyers
- Institut für Biologie und Umweltwissenschaften, Carl-von-Ossietzky-Universität Oldenburg, D-26111 Oldenburg, Germany; ,
- Research Center Neurosensory Sciences, University of Oldenburg, D-26111 Oldenburg, Germany
| | - Onur Güntürkün
- Department of Biopsychology, Institute of Cognitive Neuroscience, Faculty of Psychology, Ruhr-University Bochum, D-44780 Bochum, Germany;
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27
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Lefeldt N, Heyers D, Schneider NL, Engels S, Elbers D, Mouritsen H. Magnetic field-driven induction of ZENK in the trigeminal system of pigeons (Columba livia). J R Soc Interface 2015; 11:20140777. [PMID: 25232052 DOI: 10.1098/rsif.2014.0777] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Magnetoreception remains one of the few unsolved mysteries in sensory biology. The upper beak, which is innervated by the ophthalmic branch of the trigeminal nerve (V1), has been suggested to contain magnetic sensors based on ferromagnetic structures. Recently, its existence in pigeons has been seriously challenged by studies suggesting that the previously described iron-accumulations are macrophages, not magnetosensitive nerve endings. This raised the fundamental question of whether V1 is involved in magnetoreception in pigeons at all. We exposed pigeons to either a constantly changing magnetic field (CMF), to a zero magnetic field providing no magnetic information, or to CMF conditions after V1 was cut bilaterally. Using immediate early genes as a marker of neuronal responsiveness, we report that the trigeminal brainstem nuclei of pigeons, which receive V1 input, are activated under CMF conditions and that this neuronal activation disappears if the magnetic stimuli are removed or if V1 is cut. Our data suggest that the trigeminal system in pigeons is involved in processing magnetic field information and that V1 transmits this information from currently unknown, V1-associated magnetosensors to the brain.
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Affiliation(s)
- Nele Lefeldt
- AG Neurosensorik/Animal Navigation, Institute of Biological and Environmental Sciences, University Oldenburg, 26111 Oldenburg, Germany
| | - Dominik Heyers
- AG Neurosensorik/Animal Navigation, Institute of Biological and Environmental Sciences, University Oldenburg, 26111 Oldenburg, Germany
| | - Nils-Lasse Schneider
- AG Neurosensorik/Animal Navigation, Institute of Biological and Environmental Sciences, University Oldenburg, 26111 Oldenburg, Germany
| | - Svenja Engels
- AG Neurosensorik/Animal Navigation, Institute of Biological and Environmental Sciences, University Oldenburg, 26111 Oldenburg, Germany
| | - Dana Elbers
- AG Neurosensorik/Animal Navigation, Institute of Biological and Environmental Sciences, University Oldenburg, 26111 Oldenburg, Germany
| | - Henrik Mouritsen
- AG Neurosensorik/Animal Navigation, Institute of Biological and Environmental Sciences, University Oldenburg, 26111 Oldenburg, Germany
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28
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Kishkinev DA, Chernetsov NS. Magnetoreception systems in birds: A review of current research. ACTA ACUST UNITED AC 2015. [DOI: 10.1134/s2079086415010041] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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29
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Ramírez E, Marín G, Mpodozis J, Letelier JC. Extracellular recordings reveal absence of magneto sensitive units in the avian optic tectum. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2014; 200:983-96. [PMID: 25281335 PMCID: PMC4237910 DOI: 10.1007/s00359-014-0947-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Revised: 09/13/2014] [Accepted: 09/15/2014] [Indexed: 11/25/2022]
Abstract
There is a consensus that birds detect the earth's magnetic field and use some of its features for orientation and homing purposes. Since the late 1960s, when the first solid behavioral evidence of magnetoreception was obtained, much research has been devoted to describing the ethological aspects of this behavior. The neurophysiological basis of magnetoreception has been much less studied, although a frequently cited 1986 report described a high prevalence (70 %) of magneto-sensitive neurons in the pigeon optic tectum with high signal-to-noise ratios (Semm and Demaine, J Comp Physiol A 159:619-625, 1986). Here, we repeated these neurophysiological experiments using anesthetized as well as awake pigeons and new recording techniques. Our data indicate that magneto-sensitive units do not exist in the avian tectum.
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Affiliation(s)
- Edgardo Ramírez
- Department of Biology, Facultad de Ciencias, Universidad de Chile, Santiago, Chile,
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30
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Wiltschko R, Wiltschko W. Sensing magnetic directions in birds: radical pair processes involving cryptochrome. BIOSENSORS-BASEL 2014; 4:221-42. [PMID: 25587420 PMCID: PMC4264356 DOI: 10.3390/bios4030221] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2014] [Revised: 07/14/2014] [Accepted: 07/18/2014] [Indexed: 11/16/2022]
Abstract
Birds can use the geomagnetic field for compass orientation. Behavioral experiments, mostly with migrating passerines, revealed three characteristics of the avian magnetic compass: (1) it works spontaneously only in a narrow functional window around the intensity of the ambient magnetic field, but can adapt to other intensities, (2) it is an “inclination compass”, not based on the polarity of the magnetic field, but the axial course of the field lines, and (3) it requires short-wavelength light from UV to 565 nm Green. The Radical Pair-Model of magnetoreception can explain these properties by proposing spin-chemical processes in photopigments as underlying mechanism. Applying radio frequency fields, a diagnostic tool for radical pair processes, supports an involvement of a radical pair mechanism in avian magnetoreception: added to the geomagnetic field, they disrupted orientation, presumably by interfering with the receptive processes. Cryptochromes have been suggested as receptor molecules. Cry1a is found in the eyes of birds, where it is located at the membranes of the disks in the outer segments of the UV-cones in chickens and robins. Immuno-histochemical studies show that it is activated by the wavelengths of light that allow magnetic compass orientation in birds.
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Affiliation(s)
- Roswitha Wiltschko
- Fachbereich Biowissenschaften, J.W. Goethe-Universität Frankfurt, Max von Laue Straße 13, D-60438 Frankfurt am Main, Germany; E-Mail:
| | - Wolfgang Wiltschko
- Fachbereich Biowissenschaften, J.W. Goethe-Universität Frankfurt, Max von Laue Straße 13, D-60438 Frankfurt am Main, Germany; E-Mail:
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31
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Barkan S, Yom-Tov Y, Barnea A. A possible relation between new neuronal recruitment and migratory behavior inAcrocephaluswarblers. Dev Neurobiol 2014; 74:1194-209. [DOI: 10.1002/dneu.22198] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2014] [Revised: 05/28/2014] [Accepted: 06/02/2014] [Indexed: 12/13/2022]
Affiliation(s)
- Shay Barkan
- Department of Zoology; Tel-Aviv University; Tel-Aviv 61391 Israel
| | - Yoram Yom-Tov
- Department of Zoology; Tel-Aviv University; Tel-Aviv 61391 Israel
| | - Anat Barnea
- Department of Natural and Life Sciences; The Open University of Israel; Ra'anana 43107 Israel
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Jarvis ED, Yu J, Rivas MV, Horita H, Feenders G, Whitney O, Jarvis SC, Jarvis ER, Kubikova L, Puck AEP, Siang-Bakshi C, Martin S, McElroy M, Hara E, Howard J, Pfenning A, Mouritsen H, Chen CC, Wada K. Global view of the functional molecular organization of the avian cerebrum: mirror images and functional columns. J Comp Neurol 2014; 521:3614-65. [PMID: 23818122 DOI: 10.1002/cne.23404] [Citation(s) in RCA: 159] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 06/19/2013] [Accepted: 06/21/2013] [Indexed: 11/06/2022]
Abstract
Based on quantitative cluster analyses of 52 constitutively expressed or behaviorally regulated genes in 23 brain regions, we present a global view of telencephalic organization of birds. The patterns of constitutively expressed genes revealed a partial mirror image organization of three major cell populations that wrap above, around, and below the ventricle and adjacent lamina through the mesopallium. The patterns of behaviorally regulated genes revealed functional columns of activation across boundaries of these cell populations, reminiscent of columns through layers of the mammalian cortex. The avian functionally regulated columns were of two types: those above the ventricle and associated mesopallial lamina, formed by our revised dorsal mesopallium, hyperpallium, and intercalated hyperpallium; and those below the ventricle, formed by our revised ventral mesopallium, nidopallium, and intercalated nidopallium. Based on these findings and known connectivity, we propose that the avian pallium has four major cell populations similar to those in mammalian cortex and some parts of the amygdala: 1) a primary sensory input population (intercalated pallium); 2) a secondary intrapallial population (nidopallium/hyperpallium); 3) a tertiary intrapallial population (mesopallium); and 4) a quaternary output population (the arcopallium). Each population contributes portions to columns that control different sensory or motor systems. We suggest that this organization of cell groups forms by expansion of contiguous developmental cell domains that wrap around the lateral ventricle and its extension through the middle of the mesopallium. We believe that the position of the lateral ventricle and its associated mesopallium lamina has resulted in a conceptual barrier to recognizing related cell groups across its border, thereby confounding our understanding of homologies with mammals.
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Affiliation(s)
- Erich D Jarvis
- Department of Neurobiology, Howard Hughes Medical Institute, Duke University Medical Center, Durham, North Carolina, 27710
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Lefeldt N, Dreyer D, Steenken F, Schneider NL, Mouritsen H. Migratory blackcaps tested in Emlen funnels can orient at 85 but not at 88 degrees magnetic inclination. J Exp Biol 2014; 218:206-11. [DOI: 10.1242/jeb.107235] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Abstract
Migratory birds are known to use the Earth's magnetic field as an orientation cue on their tremendous journeys between their breeding and overwintering grounds. The magnetic compass of migratory birds relies on the magnetic field's inclination, i.e. the angle between the magnetic field lines and the Earth's surface. As a consequence, vertical or horizontal field lines corresponding to 0° or 90° inclination should offer no utilizable information on where to find North or South. So far, very little is known about how small deviations from horizontal or vertical inclination migratory birds can detect and use as a reference for their magnetic compass. Here we ask: what is the steepest inclination angle at which a migratory bird, the Eurasian blackcap (Sylvia atricapilla), can still perform magnetic compass orientation in Emlen funnels? Our results show that blackcaps are able to orient in an Earth's strength magnetic field with inclination angles of 67° and 85°, but fail to orient in a field with 88° inclination. This suggests that the steepest inclination angle enabling magnetic compass orientation in migratory blackcaps tested in Emlen funnels lies between 85 and 88 degrees.
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O'Neill P. Magnetoreception and baroreception in birds. Dev Growth Differ 2012; 55:188-97. [DOI: 10.1111/dgd.12025] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Revised: 11/01/2012] [Accepted: 11/01/2012] [Indexed: 11/28/2022]
Affiliation(s)
- Paul O'Neill
- Laboratory for Sensory Development; RIKEN Center for Developmental Biology; 2-2-3 Minatojima-Minamimachi, Chuo-ku; Kobe; 650-0047; Japan
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Bischof HJ, Nießner C, Peichl L, Wiltschko R, Wiltschko W. Avian ultraviolet/violet cones as magnetoreceptors: The problem of separating visual and magnetic information. Commun Integr Biol 2012; 4:713-6. [PMID: 22446535 DOI: 10.4161/cib.17338] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
In a recent paper, we described the localization of cryptochrome 1a in the retina of domestic chickens, Gallus gallus, and European robins, Erithacus rubecula: Cryptochrome 1a was found exclusively along the membranes of the disks in the outer segments of the ultraviolet/violet single cones. Cryptochrome has been suggested to act as receptor molecule for the avian magnetic compass, which would mean that the UV/V cones have a double function: they mediate vision in the short-wavelength range and, at the same time, magnetic directional information. This has important implications and raises a number of questions, in particular, how the two types of input are separated. Here, we point out several possibilities how this could be achieved.
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Night-migratory songbirds possess a magnetic compass in both eyes. PLoS One 2012; 7:e43271. [PMID: 22984416 PMCID: PMC3440406 DOI: 10.1371/journal.pone.0043271] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Accepted: 07/18/2012] [Indexed: 11/19/2022] Open
Abstract
Previous studies on European robins, Erithacus rubecula, and Australian silvereyes, Zosterops lateralis, had suggested that magnetic compass information is being processed only in the right eye and left brain hemisphere of migratory birds. However, recently it was demonstrated that both garden warblers, Sylvia borin, and European robins have a magnetic compass in both eyes. These results raise the question if the strong lateralization effect observed in earlier experiments might have arisen from artifacts or from differences in experimental conditions rather than reflecting a true all-or-none lateralization of the magnetic compass in European robins. Here we show that (1) European robins having only their left eye open can orient in their seasonally appropriate direction both during autumn and spring, i.e. there are no strong lateralization differences between the outward journey and the way home, that (2) their directional choices are based on the standard inclination compass as they are turned 180° when the inclination is reversed, and that (3) the capability to use the magnetic compass does not depend on monocular learning or intraocular transfer as it is already present in the first tests of the birds with only one eye open.
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Keary N, Bischof HJ. Activation changes in zebra finch (Taeniopygia guttata) brain areas evoked by alterations of the earth magnetic field. PLoS One 2012; 7:e38697. [PMID: 22679515 PMCID: PMC3367956 DOI: 10.1371/journal.pone.0038697] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2012] [Accepted: 05/11/2012] [Indexed: 11/18/2022] Open
Abstract
Many animals are able to perceive the earth magnetic field and to use it for orientation and navigation within the environment. The mechanisms underlying the perception and processing of magnetic field information within the brain have been thoroughly studied, especially in birds, but are still obscure. Three hypotheses are currently discussed, dealing with ferromagnetic particles in the beak of birds, with the same sort of particles within the lagena organs, or describing magnetically influenced radical-pair processes within retinal photopigments. Each hypothesis is related to a well-known sensory organ and claims parallel processing of magnetic field information with somatosensory, vestibular and visual input, respectively. Changes in activation within nuclei of the respective sensory systems have been shown previously. Most of these previous experiments employed intensity enhanced magnetic stimuli or lesions. We here exposed unrestrained zebra finches to either a stationary or a rotating magnetic field of the local intensity and inclination. C-Fos was used as an activity marker to examine whether the two treatments led to differences in fourteen brain areas including nuclei of the somatosensory, vestibular and visual system. An ANOVA revealed an overall effect of treatment, indicating that the magnetic field change was perceived by the birds. While the differences were too small to be significant in most areas, a significant enhancement of activation by the rotating stimulus was found in a hippocampal subdivision. Part of the hyperpallium showed a strong, nearly significant, increase. Our results are compatible with previous studies demonstrating an involvement of at least three different sensory systems in earth magnetic field perception and suggest that these systems, probably less elaborated, may also be found in nonmigrating birds.
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Affiliation(s)
- Nina Keary
- Lehrstuhl Verhaltensforschung, Universität Bielefeld, Morgenbreede 45, Bielefeld, Germany.
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Mouritsen H, Hore PJ. The magnetic retina: light-dependent and trigeminal magnetoreception in migratory birds. Curr Opin Neurobiol 2012; 22:343-52. [DOI: 10.1016/j.conb.2012.01.005] [Citation(s) in RCA: 109] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Revised: 01/03/2012] [Accepted: 01/17/2012] [Indexed: 10/28/2022]
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Rastogi A, Kumari Y, Rani S, Kumar V. Phase inversion of neural activity in the olfactory and visual systems of a night-migratory bird during migration. Eur J Neurosci 2011; 34:99-109. [DOI: 10.1111/j.1460-9568.2011.07737.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Niessner C, Denzau S, Gross JC, Peichl L, Bischof HJ, Fleissner G, Wiltschko W, Wiltschko R. Avian ultraviolet/violet cones identified as probable magnetoreceptors. PLoS One 2011; 6:e20091. [PMID: 21647441 PMCID: PMC3102070 DOI: 10.1371/journal.pone.0020091] [Citation(s) in RCA: 140] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2011] [Accepted: 04/24/2011] [Indexed: 11/23/2022] Open
Abstract
Background The Radical-Pair-Model postulates that the reception of magnetic compass directions in birds is based on spin-chemical reactions in specialized photopigments in the eye, with cryptochromes discussed as candidate molecules. But so far, the exact subcellular characterization of these molecules in the retina remained unknown. Methodology/Principal Findings We here describe the localization of cryptochrome 1a (Cry1a) in the retina of European robins, Erithacus rubecula, and domestic chickens, Gallus gallus, two species that have been shown to use the magnetic field for compass orientation. In both species, Cry1a is present exclusively in the ultraviolet/violet (UV/V) cones that are distributed across the entire retina. Electron microscopy shows Cry1a in ordered bands along the membrane discs of the outer segment, and cell fractionation reveals Cry1a in the membrane fraction, suggesting the possibility that Cry1a is anchored along membranes. Conclusions/Significance We provide first structural evidence that Cry1a occurs within a sensory structure arranged in a way that fulfils essential requirements of the Radical-Pair-Model. Our findings, identifying the UV/V-cones as probable magnetoreceptors, support the assumption that Cry1a is indeed the receptor molecule mediating information on magnetic directions, and thus provide the Radical-Pair-Model with a profound histological background.
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Affiliation(s)
- Christine Niessner
- Fachbereich Biowissenschaften der J.W. Goethe-Universität Frankfurt, Frankfurt am Main, Germany
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