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Yeganegi H, Ondracek JM. Local sleep in songbirds: different simultaneous sleep states across the avian pallium. J Sleep Res 2025; 34:e14344. [PMID: 39425588 PMCID: PMC12069731 DOI: 10.1111/jsr.14344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 08/28/2024] [Accepted: 09/01/2024] [Indexed: 10/21/2024]
Abstract
Wakefulness and sleep have often been treated as distinct and global brain states. However, an emerging body of evidence on the local regulation of sleep stages challenges this conventional view. Apart from unihemispheric sleep, the current data that support local variations of neural oscillations during sleep are focused on the homeostatic regulation of local sleep, i.e., the role preceding awake activity. Here, to examine local differences in brain activity during natural sleep, we recorded the electroencephalogram and the local field potential across multiple sites within the avian pallium of zebra finches without perturbing the previous awake state. We scored the sleep stages independently in each pallial site and found that the sleep stages are not pallium-wide phenomena but rather deviate widely across electrode sites. Importantly, deeper electrode sites had a dominant role in defining the temporal aspects of sleep state congruence. Altogether, these findings show that local regulation of sleep oscillations also occurs in the avian brain without prior awake recruitment of specific pallial circuits and in the absence of mammalian cortical neural architecture.
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Affiliation(s)
- Hamed Yeganegi
- Technical University of MunichTUM School of Life Sciences, Chair of ZoologyFreising‐WeihenstephanGermany
- Graduate School of Systemic NeurosciencesLudwig‐Maximilians‐University MunichPlaneggGermany
| | - Janie M. Ondracek
- Technical University of MunichTUM School of Life Sciences, Chair of ZoologyFreising‐WeihenstephanGermany
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2
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Konstantinides N, Desplan C. Neuronal Circuit Evolution: From Development to Structure and Adaptive Significance. Cold Spring Harb Perspect Biol 2025; 17:a041493. [PMID: 38951021 PMCID: PMC11688512 DOI: 10.1101/cshperspect.a041493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/03/2024]
Abstract
Neuronal circuits represent the functional units of the brain. Understanding how the circuits are generated to perform computations will help us understand how the brain functions. Nevertheless, neuronal circuits are not engineered, but have formed through millions of years of animal evolution. We posit that it is necessary to study neuronal circuit evolution to comprehensively understand circuit function. Here, we review our current knowledge regarding the mechanisms that underlie circuit evolution. First, we describe the possible genetic and developmental mechanisms that have contributed to circuit evolution. Then, we discuss the structural changes of circuits during evolution and how these changes affected circuit function. Finally, we try to put circuit evolution in an ecological context and assess the adaptive significance of specific examples. We argue that, thanks to the advent of new tools and technologies, evolutionary neurobiology now allows us to address questions regarding the evolution of circuitry and behavior that were unimaginable until very recently.
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Affiliation(s)
| | - Claude Desplan
- Department of Biology, New York University, New York, New York 10003, USA
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3
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Hecker N, Kempynck N, Mauduit D, Abaffyová D, Vandepoel R, Dieltiens S, Borm L, Sarropoulos I, González-Blas CB, De Man J, Davie K, Leysen E, Vandensteen J, Moors R, Hulselmans G, Lim L, De Wit J, Christiaens V, Poovathingal S, Aerts S. Enhancer-driven cell type comparison reveals similarities between the mammalian and bird pallium. Science 2025; 387:eadp3957. [PMID: 39946451 DOI: 10.1126/science.adp3957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Accepted: 11/26/2024] [Indexed: 04/23/2025]
Abstract
Combinations of transcription factors govern the identity of cell types, which is reflected by genomic enhancer codes. We used deep learning to characterize these enhancer codes and devised three metrics to compare cell types in the telencephalon across amniotes. To this end, we generated single-cell multiome and spatially resolved transcriptomics data of the chicken telencephalon. Enhancer codes of orthologous nonneuronal and γ-aminobutyric acid-mediated (GABAergic) cell types show a high degree of similarity across amniotes, whereas excitatory neurons of the mammalian neocortex and avian pallium exhibit varying degrees of similarity. Enhancer codes of avian mesopallial neurons are most similar to those of mammalian deep-layer neurons. With this study, we present generally applicable deep learning approaches to characterize and compare cell types on the basis of genomic regulatory sequences.
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Affiliation(s)
- Nikolai Hecker
- Laboratory of Computational Biology, VIB Center for AI & Computational Biology, Leuven, Belgium
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Human Genetics, KU Leuven, Leuven, Belgium
| | - Niklas Kempynck
- Laboratory of Computational Biology, VIB Center for AI & Computational Biology, Leuven, Belgium
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Human Genetics, KU Leuven, Leuven, Belgium
| | - David Mauduit
- Laboratory of Computational Biology, VIB Center for AI & Computational Biology, Leuven, Belgium
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Human Genetics, KU Leuven, Leuven, Belgium
| | - Darina Abaffyová
- Laboratory of Computational Biology, VIB Center for AI & Computational Biology, Leuven, Belgium
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Human Genetics, KU Leuven, Leuven, Belgium
| | - Roel Vandepoel
- Laboratory of Computational Biology, VIB Center for AI & Computational Biology, Leuven, Belgium
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Human Genetics, KU Leuven, Leuven, Belgium
| | - Sam Dieltiens
- Laboratory of Computational Biology, VIB Center for AI & Computational Biology, Leuven, Belgium
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Human Genetics, KU Leuven, Leuven, Belgium
| | - Lars Borm
- Laboratory of Computational Biology, VIB Center for AI & Computational Biology, Leuven, Belgium
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Human Genetics, KU Leuven, Leuven, Belgium
| | - Ioannis Sarropoulos
- Center for Molecular Biology of Heidelberg University, Heidelberg University, Heidelberg, Germany
| | - Carmen Bravo González-Blas
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Human Genetics, KU Leuven, Leuven, Belgium
| | - Julie De Man
- Laboratory of Computational Biology, VIB Center for AI & Computational Biology, Leuven, Belgium
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Human Genetics, KU Leuven, Leuven, Belgium
| | - Kristofer Davie
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Neurosciences, KU Leuven, Leuven, Belgium
| | - Elke Leysen
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Neurosciences, KU Leuven, Leuven, Belgium
| | - Jeroen Vandensteen
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Neurosciences, KU Leuven, Leuven, Belgium
| | - Rani Moors
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Neurosciences, KU Leuven, Leuven, Belgium
| | - Gert Hulselmans
- Laboratory of Computational Biology, VIB Center for AI & Computational Biology, Leuven, Belgium
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Human Genetics, KU Leuven, Leuven, Belgium
| | - Lynette Lim
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Neurosciences, KU Leuven, Leuven, Belgium
| | - Joris De Wit
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Neurosciences, KU Leuven, Leuven, Belgium
| | - Valerie Christiaens
- Laboratory of Computational Biology, VIB Center for AI & Computational Biology, Leuven, Belgium
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Human Genetics, KU Leuven, Leuven, Belgium
| | | | - Stein Aerts
- Laboratory of Computational Biology, VIB Center for AI & Computational Biology, Leuven, Belgium
- VIB-KU Leuven Center for Brain & Disease Research, Leuven, Belgium
- Department of Human Genetics, KU Leuven, Leuven, Belgium
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4
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Rueda-Alaña E, Senovilla-Ganzo R, Grillo M, Vázquez E, Marco-Salas S, Gallego-Flores T, Ordeñana-Manso A, Ftara A, Escobar L, Benguría A, Quintas A, Dopazo A, Rábano M, Vivanco MDM, Aransay AM, Garrigos D, Toval Á, Ferrán JL, Nilsson M, Encinas-Pérez JM, De Pittà M, García-Moreno F. Evolutionary convergence of sensory circuits in the pallium of amniotes. Science 2025; 387:eadp3411. [PMID: 39946453 DOI: 10.1126/science.adp3411] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Accepted: 11/20/2024] [Indexed: 04/23/2025]
Abstract
The amniote pallium contains sensory circuits that are structurally and functionally equivalent, yet their evolutionary relationship remains unresolved. We used birthdating analysis, single-cell RNA and spatial transcriptomics, and mathematical modeling to compare the development and evolution of known pallial circuits across birds (chick), lizards (gecko), and mammals (mouse). We reveal that neurons within these circuits' stations are generated at varying developmental times and brain regions across species and found an early developmental divergence in the transcriptomic progression of glutamatergic neurons. Our research highlights developmental distinctions and functional similarities in the sensory circuit between birds and mammals, suggesting the convergence of high-order sensory processing across amniote lineages.
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Affiliation(s)
- Eneritz Rueda-Alaña
- Achucarro Basque Center for Neuroscience, Scientific Park of the University of the Basque Country (UPV/EHU), Leioa, Spain
- Department of Neuroscience, Faculty of Medicine and Odontology, UPV/EHU, Barrio Sarriena s/n, Leioa, Bizkaia, Spain
| | - Rodrigo Senovilla-Ganzo
- Achucarro Basque Center for Neuroscience, Scientific Park of the University of the Basque Country (UPV/EHU), Leioa, Spain
- Department of Neuroscience, Faculty of Medicine and Odontology, UPV/EHU, Barrio Sarriena s/n, Leioa, Bizkaia, Spain
| | - Marco Grillo
- Science for Life Laboratory, Department of Biophysics and Biochemistry, Stockholm University, Solna, Sweden
| | - Enrique Vázquez
- Genomics Unit, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - Sergio Marco-Salas
- Science for Life Laboratory, Department of Biophysics and Biochemistry, Stockholm University, Solna, Sweden
| | - Tatiana Gallego-Flores
- Achucarro Basque Center for Neuroscience, Scientific Park of the University of the Basque Country (UPV/EHU), Leioa, Spain
| | - Aitor Ordeñana-Manso
- Achucarro Basque Center for Neuroscience, Scientific Park of the University of the Basque Country (UPV/EHU), Leioa, Spain
| | - Artemis Ftara
- Achucarro Basque Center for Neuroscience, Scientific Park of the University of the Basque Country (UPV/EHU), Leioa, Spain
| | - Laura Escobar
- Achucarro Basque Center for Neuroscience, Scientific Park of the University of the Basque Country (UPV/EHU), Leioa, Spain
| | - Alberto Benguría
- Genomics Unit, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - Ana Quintas
- Genomics Unit, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - Ana Dopazo
- Genomics Unit, Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBERCV), Madrid, Spain
| | - Miriam Rábano
- Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain
| | - María dM Vivanco
- Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain
| | - Ana María Aransay
- Center for Cooperative Research in Biosciences (CIC bioGUNE), Basque Research and Technology Alliance (BRTA), Bizkaia Technology Park, Derio, Spain
- Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Madrid, Spain
| | - Daniel Garrigos
- Department of Human Anatomy, Medical School, University of Murcia and Murcia Arrixaca Institute for Biomedical Research, Murcia, Spain
| | - Ángel Toval
- Department of Human Anatomy, Medical School, University of Murcia and Murcia Arrixaca Institute for Biomedical Research, Murcia, Spain
| | - José Luis Ferrán
- Department of Human Anatomy, Medical School, University of Murcia and Murcia Arrixaca Institute for Biomedical Research, Murcia, Spain
| | - Mats Nilsson
- Science for Life Laboratory, Department of Biophysics and Biochemistry, Stockholm University, Solna, Sweden
| | - Juan Manuel Encinas-Pérez
- Achucarro Basque Center for Neuroscience, Scientific Park of the University of the Basque Country (UPV/EHU), Leioa, Spain
- Department of Neuroscience, Faculty of Medicine and Odontology, UPV/EHU, Barrio Sarriena s/n, Leioa, Bizkaia, Spain
- IKERBASQUE Foundation, Bilbao, Spain
| | - Maurizio De Pittà
- Department of Neuroscience, Faculty of Medicine and Odontology, UPV/EHU, Barrio Sarriena s/n, Leioa, Bizkaia, Spain
- Basque Center for Applied Mathematics, Bilbao, Spain
- Computational Neuroscience Hub, Krembil Research Institute, University Health Network, Toronto, ON, Canada
- Department of Physiology, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Fernando García-Moreno
- Achucarro Basque Center for Neuroscience, Scientific Park of the University of the Basque Country (UPV/EHU), Leioa, Spain
- Department of Neuroscience, Faculty of Medicine and Odontology, UPV/EHU, Barrio Sarriena s/n, Leioa, Bizkaia, Spain
- IKERBASQUE Foundation, Bilbao, Spain
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5
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Zaremba B, Fallahshahroudi A, Schneider C, Schmidt J, Sarropoulos I, Leushkin E, Berki B, Van Poucke E, Jensen P, Senovilla-Ganzo R, Hervas-Sotomayor F, Trost N, Lamanna F, Sepp M, García-Moreno F, Kaessmann H. Developmental origins and evolution of pallial cell types and structures in birds. Science 2025; 387:eadp5182. [PMID: 39946461 DOI: 10.1126/science.adp5182] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Accepted: 12/03/2024] [Indexed: 04/23/2025]
Abstract
Innovations in the pallium likely facilitated the evolution of advanced cognitive abilities in birds. We therefore scrutinized its cellular composition and evolution using cell type atlases from chicken, mouse, and nonavian reptiles. We found that the avian pallium shares most inhibitory neuron types with other amniotes. Whereas excitatory neuron types in amniote hippocampal regions show evolutionary conservation, those in other pallial regions have diverged. Neurons in the avian mesopallium display gene expression profiles akin to the mammalian claustrum and deep cortical layers, while certain nidopallial cell types resemble neurons in the piriform cortex. Lastly, we observed substantial gene expression convergence between the dorsally located hyperpallium and ventrally located nidopallium during late development, suggesting that topological location does not always dictate gene expression programs determining functional properties in the adult avian pallium.
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Affiliation(s)
- Bastienne Zaremba
- Center for Molecular Biology (ZMBH), DKFZ-ZMBH Alliance, Heidelberg University, Heidelberg, Germany
| | - Amir Fallahshahroudi
- Center for Molecular Biology (ZMBH), DKFZ-ZMBH Alliance, Heidelberg University, Heidelberg, Germany
| | - Céline Schneider
- Center for Molecular Biology (ZMBH), DKFZ-ZMBH Alliance, Heidelberg University, Heidelberg, Germany
| | - Julia Schmidt
- Center for Molecular Biology (ZMBH), DKFZ-ZMBH Alliance, Heidelberg University, Heidelberg, Germany
| | - Ioannis Sarropoulos
- Center for Molecular Biology (ZMBH), DKFZ-ZMBH Alliance, Heidelberg University, Heidelberg, Germany
- Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, UK
| | - Evgeny Leushkin
- Center for Molecular Biology (ZMBH), DKFZ-ZMBH Alliance, Heidelberg University, Heidelberg, Germany
| | - Bianka Berki
- Deep Sequencing Core Facility, CellNetworks Excellence Cluster, Heidelberg University, Heidelberg, Germany
| | - Enya Van Poucke
- AVIAN Behavioural Genomics and Physiology Group, IFM Biology, Linköping University, Linköping, Sweden
| | - Per Jensen
- AVIAN Behavioural Genomics and Physiology Group, IFM Biology, Linköping University, Linköping, Sweden
| | - Rodrigo Senovilla-Ganzo
- Achucarro Basque Center for Neuroscience, Scientific Park of the University of the Basque Country (UPV/EHU), Leioa, Spain
| | | | - Nils Trost
- Center for Molecular Biology (ZMBH), DKFZ-ZMBH Alliance, Heidelberg University, Heidelberg, Germany
| | - Francesco Lamanna
- Center for Molecular Biology (ZMBH), DKFZ-ZMBH Alliance, Heidelberg University, Heidelberg, Germany
| | - Mari Sepp
- Center for Molecular Biology (ZMBH), DKFZ-ZMBH Alliance, Heidelberg University, Heidelberg, Germany
| | - Fernando García-Moreno
- Achucarro Basque Center for Neuroscience, Scientific Park of the University of the Basque Country (UPV/EHU), Leioa, Spain
- Department of Neuroscience, Faculty of Medicine and Odontology, UPV/EHU, Leioa, Spain
- IKERBASQUE Foundation, Bilbao, Spain
| | - Henrik Kaessmann
- Center for Molecular Biology (ZMBH), DKFZ-ZMBH Alliance, Heidelberg University, Heidelberg, Germany
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6
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Caspar KR, Gutiérrez-Ibáñez C, Bertrand OC, Carr T, Colbourne JAD, Erb A, George H, Holtz TR, Naish D, Wylie DR, Hurlburt GR. How smart was T. rex? Testing claims of exceptional cognition in dinosaurs and the application of neuron count estimates in palaeontological research. Anat Rec (Hoboken) 2024; 307:3685-3716. [PMID: 38668805 DOI: 10.1002/ar.25459] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2024] [Revised: 04/03/2024] [Accepted: 04/07/2024] [Indexed: 11/07/2024]
Abstract
Recent years have seen increasing scientific interest in whether neuron counts can act as correlates of diverse biological phenomena. Lately, Herculano-Houzel (2023) argued that fossil endocasts and comparative neurological data from extant sauropsids allow to reconstruct telencephalic neuron counts in Mesozoic dinosaurs and pterosaurs, which might act as proxies for behaviors and life history traits in these animals. According to this analysis, large theropods such as Tyrannosaurus rex were long-lived, exceptionally intelligent animals equipped with "macaque- or baboon-like cognition", whereas sauropods and most ornithischian dinosaurs would have displayed significantly smaller brains and an ectothermic physiology. Besides challenging established views on Mesozoic dinosaur biology, these claims raise questions on whether neuron count estimates could benefit research on fossil animals in general. Here, we address these findings by revisiting Herculano-Houzel's (2023) work, identifying several crucial shortcomings regarding analysis and interpretation. We present revised estimates of encephalization and telencephalic neuron counts in dinosaurs, which we derive from phylogenetically informed modeling and an amended dataset of endocranial measurements. For large-bodied theropods in particular, we recover significantly lower neuron counts than previously proposed. Furthermore, we review the suitability of neurological variables such as neuron numbers and relative brain size to predict cognitive complexity, metabolic rate and life history traits in dinosaurs, coming to the conclusion that they are flawed proxies for these biological phenomena. Instead of relying on such neurological estimates when reconstructing Mesozoic dinosaur biology, we argue that integrative studies are needed to approach this complex subject.
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Affiliation(s)
- Kai R Caspar
- Institute of Cell Biology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
- Department of Game Management and Wildlife Biology, Faculty of Forestry and Wood Sciences, Czech University of Life Sciences, Prague, Czech Republic
| | | | - Ornella C Bertrand
- Institut Català de Paleontologia Miquel Crusafont, Universitat Autònoma de Barcelona, Barcelona, Spain
- Section of Mammals, Carnegie Museum of Natural History, Pittsburgh, Pennsylvania, USA
| | - Thomas Carr
- Department of Biology, Carthage College, Kenosha, Wisconsin, USA
| | - Jennifer A D Colbourne
- Comparative Cognition Unit, Messerli Research Institute, University of Veterinary Medicine Vienna, Vienna, Austria
| | - Arthur Erb
- School of GeoSciences, Grant Institute, University of Edinburgh, Edinburgh, UK
- Center for Science, Teaching, and Learning, Rockville Centre, New York, USA
| | - Hady George
- School of Earth Sciences, University of Bristol, Bristol, UK
| | - Thomas R Holtz
- Department of Geology, University of Maryland, College Park, Maryland, USA
- Department of Paleobiology, National Museum of Natural History, Washington, District of Columbia, USA
| | - Darren Naish
- School of Biological Sciences, Faculty of Environment and Life Sciences, University of Southampton, Southampton, UK
| | - Douglas R Wylie
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Grant R Hurlburt
- Department of Natural History, Royal Ontario Museum, Toronto, Ontario, Canada
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7
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Hehmeyer J, Plessier F, Marlow H. Adaptive Cellular Radiations and the Genetic Mechanisms Underlying Animal Nervous System Diversification. Annu Rev Cell Dev Biol 2024; 40:407-425. [PMID: 39052757 DOI: 10.1146/annurev-cellbio-111822-124041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/27/2024]
Abstract
In animals, the nervous system evolved as the primary interface between multicellular organisms and the environment. As organisms became larger and more complex, the primary functions of the nervous system expanded to include the modulation and coordination of individual responsive cells via paracrine and synaptic functions as well as to monitor and maintain the organism's own internal environment. This was initially accomplished via paracrine signaling and eventually through the assembly of multicell circuits in some lineages. Cells with similar functions and centralized nervous systems have independently arisen in several lineages. We highlight the molecular mechanisms that underlie parallel diversifications of the nervous system.
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Affiliation(s)
- Jenks Hehmeyer
- Integrative Biology Program, The University of Chicago, Chicago, Illinois, USA
- Department of Organismal Biology and Anatomy, The University of Chicago, Chicago, Illinois, USA;
| | - Flora Plessier
- Committee on Development, Regeneration, and Stem Cell Biology, The University of Chicago, Chicago, Illinois, USA
- Department of Organismal Biology and Anatomy, The University of Chicago, Chicago, Illinois, USA;
| | - Heather Marlow
- Department of Organismal Biology and Anatomy, The University of Chicago, Chicago, Illinois, USA;
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8
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Rajan A, Fame RM. Brain development and bioenergetic changes. Neurobiol Dis 2024; 199:106550. [PMID: 38849103 PMCID: PMC11495523 DOI: 10.1016/j.nbd.2024.106550] [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: 04/15/2024] [Revised: 05/29/2024] [Accepted: 06/01/2024] [Indexed: 06/09/2024] Open
Abstract
Bioenergetics describe the biochemical processes responsible for energy supply in organisms. When these changes become dysregulated in brain development, multiple neurodevelopmental diseases can occur, implicating bioenergetics as key regulators of neural development. Historically, the discovery of disease processes affecting individual stages of brain development has revealed critical roles that bioenergetics play in generating the nervous system. Bioenergetic-dependent neurodevelopmental disorders include neural tube closure defects, microcephaly, intellectual disability, autism spectrum disorders, epilepsy, mTORopathies, and oncogenic processes. Developmental timing and cell-type specificity of these changes determine the long-term effects of bioenergetic disease mechanisms on brain form and function. Here, we discuss key metabolic regulators of neural progenitor specification, neuronal differentiation (neurogenesis), and gliogenesis. In general, transitions between glycolysis and oxidative phosphorylation are regulated in early brain development and in oncogenesis, and reactive oxygen species (ROS) and mitochondrial maturity play key roles later in differentiation. We also discuss how bioenergetics interface with the developmental regulation of other key neural elements, including the cerebrospinal fluid brain environment. While questions remain about the interplay between bioenergetics and brain development, this review integrates the current state of known key intersections between these processes in health and disease.
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Affiliation(s)
- Arjun Rajan
- Developmental Biology Graduate Program, Stanford University, Stanford, CA 94305, USA
| | - Ryann M Fame
- Department of Neurosurgery, Stanford University, Stanford, CA 94305, USA.
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9
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Yamamoto K, Estienne P, Bloch S. Does a Vertebrate Morphotype of Pallial Subdivisions Really Exist? BRAIN, BEHAVIOR AND EVOLUTION 2024; 99:230-247. [PMID: 38952102 PMCID: PMC11614313 DOI: 10.1159/000537746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 02/04/2024] [Indexed: 07/03/2024]
Abstract
BACKGROUND Comparative neuroanatomists have long sought to determine which part of the pallium in nonmammals is homologous to the mammalian neocortex. A number of similar connectivity patterns across species have led to the idea that the basic organization of the vertebrate brain is relatively conserved; thus, efforts of the last decades have been focused on determining a vertebrate "morphotype" - a model comprising the characteristics believed to have been present in the last common ancestor of all vertebrates. SUMMARY The endeavor to determine the vertebrate morphotype has been riddled with controversies due to the extensive morphological diversity of the pallium among vertebrate taxa. Nonetheless, most proposed scenarios of pallial homology are variants of a common theme where the vertebrate pallium is subdivided into subdivisions homologous to the hippocampus, neocortex, piriform cortex, and amygdala, in a one-to-one manner. We review the rationales of major propositions of pallial homology and identify the source of the discrepancies behind different hypotheses. We consider that a source of discrepancies is the prevailing assumption that there is a single "morphotype of the pallial subdivisions" throughout vertebrates. Instead, pallial subdivisions present in different taxa probably evolved independently in each lineage. KEY MESSAGES We encounter discrepancies when we search for a single morphotype of subdivisions across vertebrates. These discrepancies can be resolved by considering that several subdivisions within the pallium were established after the divergence of the different lineages. The differences of pallial organization are especially remarkable between actinopterygians (including teleost fishes) and other vertebrates. Thus, the prevailing notion of a simple one-to-one homology between the mammalian and teleost pallia needs to be reconsidered.
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Affiliation(s)
- Kei Yamamoto
- Paris-Saclay Institute of Neuroscience (Neuro-PSI), Université Paris-Saclay, CNRS UMR 9197, Saclay, France
| | - Pierre Estienne
- Paris-Saclay Institute of Neuroscience (Neuro-PSI), Université Paris-Saclay, CNRS UMR 9197, Saclay, France
| | - Solal Bloch
- Université de Tours, INSERM, Imaging Brain & Neuropsychiatry iBraiN U1253, 37032, Tours, France
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10
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Raggio M, Giaquinto D, Attanasio C, Palladino A, Esposito V, Radaelli G, De Felice E, de Girolamo P, D'Angelo L. Fasting duration impacts ribosome protein 6 phosphorylation in zebrafish brain: New insights in aquatic organisms' welfare. Ann Anat 2024; 254:152266. [PMID: 38642855 DOI: 10.1016/j.aanat.2024.152266] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2023] [Revised: 04/03/2024] [Accepted: 04/11/2024] [Indexed: 04/22/2024]
Abstract
BACKGROUND Short- or mid-term fasting, full or partial, triggers metabolic response known to have in turn health effects in an organism. At central level, the metabolic stimulus triggered by fasting is known to be perceived firstly by hypothalamic neurons. In the field of neuroscience, ribosomal protein S6 (S6) phosphorylation is commonly used as a readout of the mammalian target of rapamycin complex 1 signalling activation or as a marker for neuronal activity. The aim of this study is addressed to evaluate whether the phosphorylation of S6 occurs in the central neurons of zebrafish exposed to four (short-term) and seven (mid-term) days of complete fasting. METHODS Group-housed adult zebrafish were exposed to four and seven days of complete food withdrawal. At the end of the experimental period, Western blotting analyses were carried out to measure the expression levels of the phosphorylated S6 (pS6) by comparing the two experimental conditions versus the control group. The same antibody was then used to identify the distribution pattern of pS6 immunoreactive neurons in the whole brain and in the taste buds. RESULTS We did not observe increased pS6 levels expression in the brain of animals exposed to short-term fasting compared to the control, whereas the expression increased in brain homogenates of animals exposed to mid-term fasting. pS6 immunoreactivity was reported in some hypothalamic neurons, as well as in the dorsal area of telencephalon and preoptic area, a neurosecretory region homolog to the mammalian paraventricular nucleus. Remarkably, we observed pS6 immunostaining in the sensory cells of taste buds lining the oral epithelium. CONCLUSIONS Taken together, our data show that in zebrafish, differently from other fish species, seven days of fasting triggers neuronal activity. Furthermore, the immunostaining on sensory cells of taste buds suggests that metabolic changes may modulate also peripheral sensory cells. This event may have valuable implications when using zebrafish to design metabolic studies involving fasting as well as practical consequences on the animal welfare, in particularly stressful conditions, such as transportation.
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Affiliation(s)
- Maria Raggio
- Department of Veterinary Medicine and Animal Production, University of Naples Federico II, Via F. Delpino, Naples 1 I-80137, Italy
| | - Daniela Giaquinto
- Department of Veterinary Medicine and Animal Production, University of Naples Federico II, Via F. Delpino, Naples 1 I-80137, Italy
| | - Chiara Attanasio
- Department of Veterinary Medicine and Animal Production, University of Naples Federico II, Via F. Delpino, Naples 1 I-80137, Italy
| | - Antonio Palladino
- Department of Agricultural Science, University of Naples Federico II, Viale dell'Università, Portici, Napoli I-80055, Italy
| | - Vincenzo Esposito
- Department of Veterinary Medicine and Animal Production, University of Naples Federico II, Via F. Delpino, Naples 1 I-80137, Italy
| | - Giuseppe Radaelli
- Department of Comparative Biomedicine and Food Science (BCA), University of Padova, Viale dell'Università 16, Legnaro, Padova I-35020, Italy
| | - Elena De Felice
- School of Biosciences and Veterinary Medicine, University of Camerino, Camerino I-62032, Italy
| | - Paolo de Girolamo
- Department of Veterinary Medicine and Animal Production, University of Naples Federico II, Via F. Delpino, Naples 1 I-80137, Italy
| | - Livia D'Angelo
- Department of Veterinary Medicine and Animal Production, University of Naples Federico II, Via F. Delpino, Naples 1 I-80137, Italy.
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11
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Güntürkün O, Pusch R, Rose J. Why birds are smart. Trends Cogn Sci 2024; 28:197-209. [PMID: 38097447 PMCID: PMC10940863 DOI: 10.1016/j.tics.2023.11.002] [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: 08/31/2023] [Revised: 11/12/2023] [Accepted: 11/13/2023] [Indexed: 03/08/2024]
Abstract
Many cognitive neuroscientists believe that both a large brain and an isocortex are crucial for complex cognition. Yet corvids and parrots possess non-cortical brains of just 1-25 g, and these birds exhibit cognitive abilities comparable with those of great apes such as chimpanzees, which have brains of about 400 g. This opinion explores how this cognitive equivalence is possible. We propose four features that may be required for complex cognition: a large number of associative pallial neurons, a prefrontal cortex (PFC)-like area, a dense dopaminergic innervation of association areas, and dynamic neurophysiological fundaments for working memory. These four neural features have convergently evolved and may therefore represent 'hard to replace' mechanisms enabling complex cognition.
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Affiliation(s)
- Onur Güntürkün
- Biopsychology, Institute of Cognitive Neuroscience, Faculty of Psychology, Ruhr University Bochum, 44780 Bochum, Germany; Research Center One Health Ruhr, Research Alliance Ruhr, Ruhr University Bochum, Bochum, Germany.
| | - Roland Pusch
- Biopsychology, Institute of Cognitive Neuroscience, Faculty of Psychology, Ruhr University Bochum, 44780 Bochum, Germany
| | - Jonas Rose
- Neural Basis of Learning, Faculty of Psychology, Ruhr University Bochum, 44780 Bochum, Germany
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12
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Suresh H, Crow M, Jorstad N, Hodge R, Lein E, Dobin A, Bakken T, Gillis J. Comparative single-cell transcriptomic analysis of primate brains highlights human-specific regulatory evolution. Nat Ecol Evol 2023; 7:1930-1943. [PMID: 37667001 PMCID: PMC10627823 DOI: 10.1038/s41559-023-02186-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 08/02/2023] [Indexed: 09/06/2023]
Abstract
Enhanced cognitive function in humans is hypothesized to result from cortical expansion and increased cellular diversity. However, the mechanisms that drive these phenotypic innovations remain poorly understood, in part because of the lack of high-quality cellular resolution data in human and non-human primates. Here, we take advantage of single-cell expression data from the middle temporal gyrus of five primates (human, chimp, gorilla, macaque and marmoset) to identify 57 homologous cell types and generate cell type-specific gene co-expression networks for comparative analysis. Although orthologue expression patterns are generally well conserved, we find 24% of genes with extensive differences between human and non-human primates (3,383 out of 14,131), which are also associated with multiple brain disorders. To assess the functional significance of gene expression differences in an evolutionary context, we evaluate changes in network connectivity across meta-analytic co-expression networks from 19 animals. We find that a subset of these genes has deeply conserved co-expression across all non-human animals, and strongly divergent co-expression relationships in humans (139 out of 3,383, <1% of primate orthologues). Genes with human-specific cellular expression and co-expression profiles (such as NHEJ1, GTF2H2, C2 and BBS5) typically evolve under relaxed selective constraints and may drive rapid evolutionary change in brain function.
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Affiliation(s)
- Hamsini Suresh
- Stanley Institute for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | | | | | | | - Ed Lein
- Allen Institute for Brain Science, Seattle, WA, USA
| | - Alexander Dobin
- Stanley Institute for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA
| | | | - Jesse Gillis
- Stanley Institute for Cognitive Genomics, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, USA.
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada.
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13
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Lamanna F, Hervas-Sotomayor F, Oel AP, Jandzik D, Sobrido-Cameán D, Santos-Durán GN, Martik ML, Stundl J, Green SA, Brüning T, Mößinger K, Schmidt J, Schneider C, Sepp M, Murat F, Smith JJ, Bronner ME, Rodicio MC, Barreiro-Iglesias A, Medeiros DM, Arendt D, Kaessmann H. A lamprey neural cell type atlas illuminates the origins of the vertebrate brain. Nat Ecol Evol 2023; 7:1714-1728. [PMID: 37710042 PMCID: PMC10555824 DOI: 10.1038/s41559-023-02170-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 07/18/2023] [Indexed: 09/16/2023]
Abstract
The vertebrate brain emerged more than ~500 million years ago in common evolutionary ancestors. To systematically trace its cellular and molecular origins, we established a spatially resolved cell type atlas of the entire brain of the sea lamprey-a jawless species whose phylogenetic position affords the reconstruction of ancestral vertebrate traits-based on extensive single-cell RNA-seq and in situ sequencing data. Comparisons of this atlas to neural data from the mouse and other jawed vertebrates unveiled various shared features that enabled the reconstruction of cell types, tissue structures and gene expression programs of the ancestral vertebrate brain. However, our analyses also revealed key tissues and cell types that arose later in evolution. For example, the ancestral brain was probably devoid of cerebellar cell types and oligodendrocytes (myelinating cells); our data suggest that the latter emerged from astrocyte-like evolutionary precursors in the jawed vertebrate lineage. Altogether, our work illuminates the cellular and molecular architecture of the ancestral vertebrate brain and provides a foundation for exploring its diversification during evolution.
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Affiliation(s)
- Francesco Lamanna
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany.
| | | | - A Phillip Oel
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - David Jandzik
- Department of Ecology and Evolutionary Biology, University of Colorado Boulder, Boulder, CO, USA
- Department of Zoology, Comenius University, Bratislava, Slovakia
| | - Daniel Sobrido-Cameán
- Department of Functional Biology, CIBUS, Faculty of Biology, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Gabriel N Santos-Durán
- Department of Functional Biology, CIBUS, Faculty of Biology, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Megan L Martik
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
- Department of Molecular and Cell Biology, University of California Berkeley, Berkeley, CA, USA
| | - Jan Stundl
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Stephen A Green
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Thoomke Brüning
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany
| | - Katharina Mößinger
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany
| | - Julia Schmidt
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany
| | - Celine Schneider
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany
| | - Mari Sepp
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany
| | - Florent Murat
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany
- INRAE, LPGP, Rennes, France
| | - Jeramiah J Smith
- Department of Biology, University of Kentucky, Lexington, KY, USA
| | - Marianne E Bronner
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - María Celina Rodicio
- Department of Functional Biology, CIBUS, Faculty of Biology, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Antón Barreiro-Iglesias
- Department of Functional Biology, CIBUS, Faculty of Biology, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Daniel M Medeiros
- Department of Ecology and Evolutionary Biology, University of Colorado Boulder, Boulder, CO, USA
| | - Detlev Arendt
- Developmental Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Henrik Kaessmann
- Center for Molecular Biology of Heidelberg University (ZMBH), DKFZ-ZMBH Alliance, Heidelberg, Germany.
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14
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Huilgol D, Levine JM, Galbavy W, Wang BS, He M, Suryanarayana SM, Huang ZJ. Direct and indirect neurogenesis generate a mosaic of distinct glutamatergic projection neuron types in cerebral cortex. Neuron 2023; 111:2557-2569.e4. [PMID: 37348506 PMCID: PMC10527425 DOI: 10.1016/j.neuron.2023.05.021] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 02/27/2023] [Accepted: 05/23/2023] [Indexed: 06/24/2023]
Abstract
Variations in size and complexity of the cerebral cortex result from differences in neuron number and composition, rooted in evolutionary changes in direct and indirect neurogenesis (dNG and iNG) that are mediated by radial glia and intermediate progenitors (IPs), respectively. How dNG and iNG differentially contribute to neuronal number, diversity, and connectivity are unknown. Establishing a genetic fate-mapping method to differentially visualize dNG and iNG in mice, we found that while both dNG and iNG contribute to all cortical structures, iNG contributes the largest relative proportions to the hippocampus and neocortex. Within the neocortex, whereas dNG generates all major glutamatergic projection neuron (PN) classes, iNG differentially amplifies and diversifies PNs within each class; the two pathways generate distinct PN types and assemble fine mosaics of lineage-based cortical subnetworks. Our results establish a ground-level lineage framework for understanding cortical development and evolution by linking foundational progenitor types and neurogenic pathways to PN types.
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Affiliation(s)
- Dhananjay Huilgol
- Department of Neurobiology, Duke University Medical Center, Durham, NC 27710, USA; Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Jesse M Levine
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA; Program in Neuroscience and Medical Scientist Training Program, Stony Brook University, Stony Brook, NY 11794, USA
| | - William Galbavy
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA; Program in Neuroscience, Department of Neurobiology and Behavior, Stony Brook University, Stony Brook, NY 11794, USA
| | - Bor-Shuen Wang
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA
| | - Miao He
- Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA; Institutes of Brain Science, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Department of Neurobiology, Zhongshan Hospital, Fudan University, Shanghai 200032, China
| | | | - Z Josh Huang
- Department of Neurobiology, Duke University Medical Center, Durham, NC 27710, USA; Department of Biomedical Engineering, Duke University, Durham, NC 27708, USA; Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA.
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15
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Kozol RA, Conith AJ, Yuiska A, Cree-Newman A, Tolentino B, Benesh K, Paz A, Lloyd E, Kowalko JE, Keene AC, Albertson C, Duboue ER. A brain-wide analysis maps structural evolution to distinct anatomical module. eLife 2023; 12:e80777. [PMID: 37498318 PMCID: PMC10435234 DOI: 10.7554/elife.80777] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 07/26/2023] [Indexed: 07/28/2023] Open
Abstract
The vertebrate brain is highly conserved topologically, but less is known about neuroanatomical variation between individual brain regions. Neuroanatomical variation at the regional level is hypothesized to provide functional expansion, building upon ancestral anatomy needed for basic functions. Classically, animal models used to study evolution have lacked tools for detailed anatomical analysis that are widely used in zebrafish and mice, presenting a barrier to studying brain evolution at fine scales. In this study, we sought to investigate the evolution of brain anatomy using a single species of fish consisting of divergent surface and cave morphs, that permits functional genetic testing of regional volume and shape across the entire brain. We generated a high-resolution brain atlas for the blind Mexican cavefish Astyanax mexicanus and coupled the atlas with automated computational tools to directly assess variability in brain region shape and volume across all populations. We measured the volume and shape of every grossly defined neuroanatomical region of the brain and assessed correlations between anatomical regions in surface fish, cavefish, and surface × cave F2 hybrids, whose phenotypes span the range of surface to cave. We find that dorsal regions of the brain are contracted, while ventral regions have expanded, with F2 hybrid data providing support for developmental constraint along the dorsal-ventral axis. Furthermore, these dorsal-ventral relationships in anatomical variation show similar patterns for both volume and shape, suggesting that the anatomical evolution captured by these two parameters could be driven by similar developmental mechanisms. Together, these data demonstrate that A. mexicanus is a powerful system for functionally determining basic principles of brain evolution and will permit testing how genes influence early patterning events to drive brain-wide anatomical evolution.
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Affiliation(s)
- Robert A Kozol
- Jupiter Life Science Initiative, Florida Atlantic UniversityJupiterUnited States
| | - Andrew J Conith
- Department of Biology, University of Massachusetts AmherstAmherstUnited States
| | - Anders Yuiska
- Jupiter Life Science Initiative, Florida Atlantic UniversityJupiterUnited States
| | - Alexia Cree-Newman
- Jupiter Life Science Initiative, Florida Atlantic UniversityJupiterUnited States
| | - Bernadeth Tolentino
- Jupiter Life Science Initiative, Florida Atlantic UniversityJupiterUnited States
| | - Kasey Benesh
- Jupiter Life Science Initiative, Florida Atlantic UniversityJupiterUnited States
| | - Alexandra Paz
- Jupiter Life Science Initiative, Florida Atlantic UniversityJupiterUnited States
| | - Evan Lloyd
- Department of Biology, Texas A&M UniversityCollege StationUnited States
| | - Johanna E Kowalko
- Department of Biological Sciences, Lehigh UniversityBethlehemUnited States
| | - Alex C Keene
- Department of Biology, Texas A&M UniversityCollege StationUnited States
| | - Craig Albertson
- Department of Biology, University of Massachusetts AmherstAmherstUnited States
| | - Erik R Duboue
- Jupiter Life Science Initiative, Florida Atlantic UniversityJupiterUnited States
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16
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Mikulasch FA, Rudelt L, Wibral M, Priesemann V. Where is the error? Hierarchical predictive coding through dendritic error computation. Trends Neurosci 2023; 46:45-59. [PMID: 36577388 DOI: 10.1016/j.tins.2022.09.007] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Revised: 09/28/2022] [Accepted: 09/28/2022] [Indexed: 11/19/2022]
Abstract
Top-down feedback in cortex is critical for guiding sensory processing, which has prominently been formalized in the theory of hierarchical predictive coding (hPC). However, experimental evidence for error units, which are central to the theory, is inconclusive and it remains unclear how hPC can be implemented with spiking neurons. To address this, we connect hPC to existing work on efficient coding in balanced networks with lateral inhibition and predictive computation at apical dendrites. Together, this work points to an efficient implementation of hPC with spiking neurons, where prediction errors are computed not in separate units, but locally in dendritic compartments. We then discuss the correspondence of this model to experimentally observed connectivity patterns, plasticity, and dynamics in cortex.
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Affiliation(s)
- Fabian A Mikulasch
- Max-Planck-Institute for Dynamics and Self-Organization, Göttingen, Germany.
| | - Lucas Rudelt
- Max-Planck-Institute for Dynamics and Self-Organization, Göttingen, Germany
| | - Michael Wibral
- Göttingen Campus Institute for Dynamics of Biological Networks, Georg-August University, Göttingen, Germany
| | - Viola Priesemann
- Max-Planck-Institute for Dynamics and Self-Organization, Göttingen, Germany; Bernstein Center for Computational Neuroscience (BCCN), Göttingen, Germany; Department of Physics, Georg-August University, Göttingen, Germany
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17
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Deryckere A, Woych J, Jaeger ECB, Tosches MA. Molecular Diversity of Neuron Types in the Salamander Amygdala and Implications for Amygdalar Evolution. BRAIN, BEHAVIOR AND EVOLUTION 2022; 98:61-75. [PMID: 36574764 PMCID: PMC10096051 DOI: 10.1159/000527899] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 10/21/2022] [Indexed: 12/28/2022]
Abstract
The amygdala is a complex brain structure in the vertebrate telencephalon, essential for regulating social behaviors, emotions, and (social) cognition. In contrast to the vast majority of neuron types described in the many nuclei of the mammalian amygdala, little is known about the neuronal diversity in non-mammals, making reconstruction of its evolution particularly difficult. Here, we characterize glutamatergic neuron types in the amygdala of the urodele amphibian Pleurodeles waltl. Our single-cell RNA sequencing data indicate the existence of at least ten distinct types and subtypes of glutamatergic neurons in the salamander amygdala. These neuron types are molecularly distinct from neurons in the ventral pallium (VP), suggesting that the pallial amygdala and the VP are two separate areas in the telencephalon. In situ hybridization for marker genes indicates that amygdalar glutamatergic neuron types are located in three major subdivisions: the lateral amygdala, the medial amygdala, and a newly defined area demarcated by high expression of the transcription factor Sim1. The gene expression profiles of these neuron types suggest similarities with specific neurons in the sauropsid and mammalian amygdala. In particular, we identify Sim1+ and Sim1+ Otp+ expressing neuron types, potentially homologous to the mammalian nucleus of the lateral olfactory tract (NLOT) and to hypothalamic-derived neurons of the medial amygdala, respectively. Taken together, our results reveal a surprising diversity of glutamatergic neuron types in the amygdala of salamanders, despite the anatomical simplicity of their brain. These results offer new insights on the cellular and anatomical complexity of the amygdala in tetrapod ancestors.
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Affiliation(s)
- Astrid Deryckere
- Department of Biological Sciences, Columbia University; New York, NY 10027, USA
| | - Jamie Woych
- Department of Biological Sciences, Columbia University; New York, NY 10027, USA
| | - Eliza C. B. Jaeger
- Department of Biological Sciences, Columbia University; New York, NY 10027, USA
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18
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Hussan MT, Sakai A, Matsui H. Glutamatergic pathways in the brains of turtles: A comparative perspective among reptiles, birds, and mammals. Front Neuroanat 2022; 16:937504. [PMID: 36059432 PMCID: PMC9428285 DOI: 10.3389/fnana.2022.937504] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 07/22/2022] [Indexed: 11/13/2022] Open
Abstract
Glutamate acts as the main excitatory neurotransmitter in the brain and plays a vital role in physiological and pathological neuronal functions. In mammals, glutamate can cause detrimental excitotoxic effects under anoxic conditions. In contrast, Trachemys scripta, a freshwater turtle, is one of the most anoxia-tolerant animals, being able to survive up to months without oxygen. Therefore, turtles have been investigated to assess the molecular mechanisms of neuroprotective strategies used by them in anoxic conditions, such as maintaining low levels of glutamate, increasing adenosine and GABA, upregulating heat shock proteins, and downregulating KATP channels. These mechanisms of anoxia tolerance of the turtle brain may be applied to finding therapeutics for human glutamatergic neurological disorders such as brain injury or cerebral stroke due to ischemia. Despite the importance of glutamate as a neurotransmitter and of the turtle as an ideal research model, the glutamatergic circuits in the turtle brain remain less described whereas they have been well studied in mammalian and avian brains. In reptiles, particularly in the turtle brain, glutamatergic neurons have been identified by examining the expression of vesicular glutamate transporters (VGLUTs). In certain areas of the brain, some ionotropic glutamate receptors (GluRs) have been immunohistochemically studied, implying that there are glutamatergic target areas. Based on the expression patterns of these glutamate-related molecules and fiber connection data of the turtle brain that is available in the literature, many candidate glutamatergic circuits could be clarified, such as the olfactory circuit, hippocampal–septal pathway, corticostriatal pathway, visual pathway, auditory pathway, and granule cell–Purkinje cell pathway. This review summarizes the probable glutamatergic pathways and the distribution of glutamatergic neurons in the pallium of the turtle brain and compares them with those of avian and mammalian brains. The integrated knowledge of glutamatergic pathways serves as the fundamental basis for further functional studies in the turtle brain, which would provide insights on physiological and pathological mechanisms of glutamate regulation as well as neural circuits in different species.
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Affiliation(s)
- Mohammad Tufazzal Hussan
- Department of Neuroscience of Disease, Brain Research Institute, Niigata University, Niigata, Japan
- Department of Anatomy and Histology, Patuakhali Science and Technology University, Barishal, Bangladesh
- *Correspondence: Mohammad Tufazzal Hussan,
| | - Akiko Sakai
- Department of Neuroscience of Disease, Brain Research Institute, Niigata University, Niigata, Japan
| | - Hideaki Matsui
- Department of Neuroscience of Disease, Brain Research Institute, Niigata University, Niigata, Japan
- Hideaki Matsui,
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19
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Espinós A, Fernández‐Ortuño E, Negri E, Borrell V. Evolution of genetic mechanisms regulating cortical neurogenesis. Dev Neurobiol 2022; 82:428-453. [PMID: 35670518 PMCID: PMC9543202 DOI: 10.1002/dneu.22891] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 04/26/2022] [Accepted: 05/24/2022] [Indexed: 11/20/2022]
Abstract
The size of the cerebral cortex increases dramatically across amniotes, from reptiles to great apes. This is primarily due to different numbers of neurons and glial cells produced during embryonic development. The evolutionary expansion of cortical neurogenesis was linked to changes in neural stem and progenitor cells, which acquired increased capacity of self‐amplification and neuron production. Evolution works via changes in the genome, and recent studies have identified a small number of new genes that emerged in the recent human and primate lineages, promoting cortical progenitor proliferation and increased neurogenesis. However, most of the mammalian genome corresponds to noncoding DNA that contains gene‐regulatory elements, and recent evidence precisely points at changes in expression levels of conserved genes as key in the evolution of cortical neurogenesis. Here, we provide an overview of basic cellular mechanisms involved in cortical neurogenesis across amniotes, and discuss recent progress on genetic mechanisms that may have changed during evolution, including gene expression regulation, leading to the expansion of the cerebral cortex.
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Affiliation(s)
- Alexandre Espinós
- Instituto de Neurociencias CSIC ‐ UMH, 03550 Sant Joan d'Alacant Spain
| | | | - Enrico Negri
- Instituto de Neurociencias CSIC ‐ UMH, 03550 Sant Joan d'Alacant Spain
| | - Víctor Borrell
- Instituto de Neurociencias CSIC ‐ UMH, 03550 Sant Joan d'Alacant Spain
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20
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Colquitt BM. Organizational Conservation and Flexibility in the Evolution of Birdsong and Avian Motor Control. BRAIN, BEHAVIOR AND EVOLUTION 2022; 97:255-264. [PMID: 35644127 DOI: 10.1159/000525019] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 05/05/2022] [Indexed: 06/15/2023]
Abstract
Birds and mammals have independently evolved complex behavioral and cognitive capabilities yet have markedly different brain structures. An open question is to what extent, despite these differences in anatomy, birds and mammals have evolved similar neural solutions to complex motor control and at what level of organization these similarities might lie. Courtship song in songbirds, a learned motor skill that is similar to the fine motor skills of many mammals including human speech, provides a powerful system in which to study the links connecting the development and evolution of cells, circuits, and behavior. Until recently, obtaining cellular-resolution views of the specialized neural circuitry that subserves birdsong was impossible due to a lack of molecular tools for songbirds. However, the ongoing revolution in cellular profiling and genomics offers unprecedented opportunities for molecular analysis in organisms that lack a traditional genetic infrastructure but have tractable, well-defined behaviors. Here, I describe recent efforts to understand the evolutionary relationships between birdsong control circuitry and mammalian neocortical circuitry using new approaches to measure gene expression in single cells. These results, combined with foundational work relating avian and mammalian brains at a range of biological levels, present an emerging view that amniote pallium evolution is a story of diverse neural circuit architectures employing conserved neuronal elements within a conserved topological framework. This view suggests that one locus of pallial neural circuit evolution lies at the intersection between the gene regulatory programs that regulate regional patterning and those that specify functional identity. Modifications to this intersection may underlie the evolution of pallial motor control in birds in general and to the evolutionary and developmental relationships of these circuits to the avian pallial amygdala.
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Affiliation(s)
- Bradley M Colquitt
- Howard Hughes Medical Institute, Chevy Chase, Maryland, USA
- Department of Physiology, University of California-San Francisco, San Francisco, California, USA
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21
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Nomura T, Gotoh H, Kiyonari H, Ono K. Cell Type-Specific Transcriptional Control of Gsk3β in the Developing Mammalian Neocortex. Front Neurosci 2022; 16:811689. [PMID: 35401100 PMCID: PMC8983961 DOI: 10.3389/fnins.2022.811689] [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: 11/09/2021] [Accepted: 02/15/2022] [Indexed: 11/16/2022] Open
Abstract
Temporal control of neurogenesis is central for the development and evolution of species-specific brain architectures. The balance between progenitor expansion and neuronal differentiation is tightly coordinated by cell-intrinsic and cell-extrinsic cues. Wnt signaling plays pivotal roles in the proliferation and differentiation of neural progenitors in a temporal manner. However, regulatory mechanisms that adjust intracellular signaling amplitudes according to cell fate progression remain to be elucidated. Here, we report the transcriptional controls of Gsk3β, a critical regulator of Wnt signaling, in the developing mouse neocortex. Gsk3β expression was higher in ventricular neural progenitors, while it gradually declined in differentiated neurons. We identified active cis-regulatory module (CRM) of Gsk3β that responded to cell type-specific transcription factors, such as Sox2, Sox9, and Neurogenin2. Furthermore, we found extensive conservation of the CRM among mammals but not in non-mammalian amniotes. Our data suggest that a mammalian-specific CRM drives the cell type-specific activity of Gsk3β to fine tune Wnt signaling, which contributes to the tight control of neurogenesis during neocortical development.
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Affiliation(s)
- Tadashi Nomura
- Developmental Neurobiology, INAMORI Memorial Building, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Hitoshi Gotoh
- Developmental Neurobiology, INAMORI Memorial Building, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Hiroshi Kiyonari
- Laboratory for Animal Resources and Genetic Engineering, RIKEN Center for Biosystems Dynamics Research, Kobe, Japan
| | - Katsuhiko Ono
- Developmental Neurobiology, INAMORI Memorial Building, Kyoto Prefectural University of Medicine, Kyoto, Japan
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22
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Nian FS, Hou PS. Evolving Roles of Notch Signaling in Cortical Development. Front Neurosci 2022; 16:844410. [PMID: 35422684 PMCID: PMC9001970 DOI: 10.3389/fnins.2022.844410] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Accepted: 02/15/2022] [Indexed: 01/09/2023] Open
Abstract
Expansion of the neocortex is thought to pave the way toward acquisition of higher cognitive functions in mammals. The highly conserved Notch signaling pathway plays a crucial role in this process by regulating the size of the cortical progenitor pool, in part by controlling the balance between self-renewal and differentiation. In this review, we introduce the components of Notch signaling pathway as well as the different mode of molecular mechanisms, including trans- and cis-regulatory processes. We focused on the recent findings with regard to the expression pattern and levels in regulating neocortical formation in mammals and its interactions with other known signaling pathways, including Slit–Robo signaling and Shh signaling. Finally, we review the functions of Notch signaling pathway in different species as well as other developmental process, mainly somitogenesis, to discuss how modifications to the Notch signaling pathway can drive the evolution of the neocortex.
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Affiliation(s)
- Fang-Shin Nian
- Institute of Anatomy and Cell Biology, National Yang Ming Chiao Tung University, Taipei, Taiwan
- Institute of Brain Science, College of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Pei-Shan Hou
- Institute of Anatomy and Cell Biology, National Yang Ming Chiao Tung University, Taipei, Taiwan
- Brain Research Center, National Yang Ming Chiao Tung University, Taipei, Taiwan
- *Correspondence: Pei-Shan Hou,
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Suryanarayana SM, Robertson B, Grillner S. The neural bases of vertebrate motor behaviour through the lens of evolution. Philos Trans R Soc Lond B Biol Sci 2022; 377:20200521. [PMID: 34957847 PMCID: PMC8710883 DOI: 10.1098/rstb.2020.0521] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 08/27/2021] [Indexed: 12/23/2022] Open
Abstract
The primary driver of the evolution of the vertebrate nervous system has been the necessity to move, along with the requirement of controlling the plethora of motor behavioural repertoires seen among the vast and diverse vertebrate species. Understanding the neural basis of motor control through the perspective of evolution, mandates thorough examinations of the nervous systems of species in critical phylogenetic positions. We present here, a broad review of studies on the neural motor infrastructure of the lamprey, a basal and ancient vertebrate, which enjoys a unique phylogenetic position as being an extant representative of the earliest group of vertebrates. From the central pattern generators in the spinal cord to the microcircuits of the pallial cortex, work on the lamprey brain over the years, has provided detailed insights into the basic organization (a bauplan) of the ancestral vertebrate brain, and narrates a compelling account of common ancestry of fundamental aspects of the neural bases for motion control, maintained through half a billion years of vertebrate evolution. This article is part of the theme issue 'Systems neuroscience through the lens of evolutionary theory'.
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Affiliation(s)
- Shreyas M. Suryanarayana
- Department of Neuroscience, Karolinska institutet, 17177 Stockholm, Sweden
- Department of Neurobiology, Duke University Medical Center, Durham, NC 27710, USA
| | - Brita Robertson
- Department of Neuroscience, Karolinska institutet, 17177 Stockholm, Sweden
| | - Sten Grillner
- Department of Neuroscience, Karolinska institutet, 17177 Stockholm, Sweden
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24
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Kozulin P, Suárez R, Zhao QY, Paolino A, Richards LJ, Fenlon LR. Divergent evolution of developmental timing in the neocortex revealed by marsupial and eutherian transcriptomes. Development 2022; 149:274319. [DOI: 10.1242/dev.200212] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 12/20/2021] [Indexed: 12/13/2022]
Abstract
ABSTRACT
Only mammals evolved a neocortex, which integrates sensory-motor and cognitive functions. Significant diversifications in the cellular composition and connectivity of the neocortex occurred between the two main therian groups: marsupials and eutherians. However, the developmental mechanisms underlying these diversifications are largely unknown. Here, we compared the neocortical transcriptomes of Sminthopsis crassicaudata, a mouse-sized marsupial, with those of eutherian mice at two developmentally equivalent time points corresponding to deeper and upper layer neuron generation. Enrichment analyses revealed more mature gene networks in marsupials at the early stage, which reverted at the later stage, suggesting a more precocious but protracted neuronal maturation program relative to birth timing of cortical layers. We ranked genes expressed in different species and identified important differences in gene expression rankings between species. For example, genes known to be enriched in upper-layer cortical projection neuron subtypes, such as Cux1, Lhx2 and Satb2, likely relate to corpus callosum emergence in eutherians. These results show molecular heterochronies of neocortical development in Theria, and highlight changes in gene expression and cell type composition that may underlie neocortical evolution and diversification.
This article has an associated ‘The people behind the papers’ interview.
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Affiliation(s)
- Peter Kozulin
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Rodrigo Suárez
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Qiong-Yi Zhao
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Annalisa Paolino
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Linda J. Richards
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Laura R. Fenlon
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
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25
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Le Dréau G. BuMPing Into Neurogenesis: How the Canonical BMP Pathway Regulates Neural Stem Cell Divisions Throughout Space and Time. Front Neurosci 2022; 15:819990. [PMID: 35153664 PMCID: PMC8829030 DOI: 10.3389/fnins.2021.819990] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 12/28/2021] [Indexed: 11/13/2022] Open
Abstract
Bone morphogenetic proteins (BMPs) are secreted factors that contribute to many aspects of the formation of the vertebrate central nervous system (CNS), from the initial shaping of the neural primordium to the maturation of the brain and spinal cord. In particular, the canonical (SMAD1/5/8-dependent) BMP pathway appears to play a key role during neurogenesis, its activity dictating neural stem cell fate decisions and thereby regulating the growth and homeostasis of the CNS. In this mini-review, I summarize accumulating evidence demonstrating how the canonical BMP activity promotes the amplification and/or maintenance of neural stem cells at different times and in diverse regions of the vertebrate CNS, and highlight findings suggesting that this function is evolutionarily conserved.
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26
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Rajan A, Ostgaard CM, Lee CY. Regulation of Neural Stem Cell Competency and Commitment during Indirect Neurogenesis. Int J Mol Sci 2021; 22:12871. [PMID: 34884676 PMCID: PMC8657492 DOI: 10.3390/ijms222312871] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Revised: 11/24/2021] [Accepted: 11/24/2021] [Indexed: 11/29/2022] Open
Abstract
Indirect neurogenesis, during which neural stem cells generate neurons through intermediate progenitors, drives the evolution of lissencephalic brains to gyrencephalic brains. The mechanisms that specify intermediate progenitor identity and that regulate stem cell competency to generate intermediate progenitors remain poorly understood despite their roles in indirect neurogenesis. Well-characterized lineage hierarchy and available powerful genetic tools for manipulating gene functions make fruit fly neural stem cell (neuroblast) lineages an excellent in vivo paradigm for investigating the mechanisms that regulate neurogenesis. Type II neuroblasts in fly larval brains repeatedly undergo asymmetric divisions to generate intermediate neural progenitors (INPs) that undergo limited proliferation to increase the number of neurons generated per stem cell division. Here, we review key regulatory genes and the mechanisms by which they promote the specification and generation of INPs, safeguarding the indirect generation of neurons during fly larval brain neurogenesis. Homologs of these regulators of INPs have been shown to play important roles in regulating brain development in vertebrates. Insight into the precise regulation of intermediate progenitors will likely improve our understanding of the control of indirect neurogenesis during brain development and brain evolution.
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Affiliation(s)
- Arjun Rajan
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA; (A.R.); (C.M.O.)
| | - Cyrina M. Ostgaard
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA; (A.R.); (C.M.O.)
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Cheng-Yu Lee
- Life Sciences Institute, University of Michigan, Ann Arbor, MI 48109, USA; (A.R.); (C.M.O.)
- Department of Cell and Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48109, USA
- Division of Genetic Medicine, Department of Internal Medicine and Comprehensive Cancer Center, University of Michigan Medical School, Ann Arbor, MI 48109, USA
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Medina L, Abellán A, Desfilis E. Evolving Views on the Pallium. BRAIN, BEHAVIOR AND EVOLUTION 2021; 96:181-199. [PMID: 34657034 DOI: 10.1159/000519260] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 08/24/2021] [Indexed: 12/14/2022]
Abstract
The pallium is the largest part of the telencephalon in amniotes, and comparison of its subdivisions across species has been extremely difficult and controversial due to its high divergence. Comparative embryonic genoarchitecture studies have greatly contributed to propose models of pallial fundamental divisions, which can be compared across species and be used to extract general organizing principles as well as to ask more focused and insightful research questions. The use of these models is crucial to discern between conservation, convergence or divergence in the neural populations and networks found in the pallium. Here we provide a critical review of the models proposed using this approach, including tetrapartite, hexapartite and double-ring models, and compare them to other models. While recognizing the power of these models for understanding brain architecture, development and evolution, we also highlight limitations and comment on aspects that require attention for improvement. We also discuss on the use of transcriptomic data for understanding pallial evolution and advise for better contextualization of these data by discerning between gene regulatory networks involved in the generation of specific units and cell populations versus genes expressed later, many of which are activity dependent and their expression is more likely subjected to convergent evolution.
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Affiliation(s)
- Loreta Medina
- Department of Experimental Medicine, Faculty of Medicine, University of Lleida, Lleida's Institute for Biomedical Research - Dr. Pifarré Foundation (IRBLleida), Lleida, Spain
| | - Antonio Abellán
- Department of Experimental Medicine, Faculty of Medicine, University of Lleida, Lleida's Institute for Biomedical Research - Dr. Pifarré Foundation (IRBLleida), Lleida, Spain
| | - Ester Desfilis
- Department of Experimental Medicine, Faculty of Medicine, University of Lleida, Lleida's Institute for Biomedical Research - Dr. Pifarré Foundation (IRBLleida), Lleida, Spain
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28
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Nieder A. Consciousness without cortex. Curr Opin Neurobiol 2021; 71:69-76. [PMID: 34656051 DOI: 10.1016/j.conb.2021.09.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Accepted: 09/16/2021] [Indexed: 11/17/2022]
Abstract
Sensory consciousness - the awareness and ability to report subjective experiences - is a property of biological nervous systems that has evolved out of unconscious processing over hundreds of millions of years. From which brain structures and based on which mechanisms can conscious experience emerge? Based on the body of work in human and nonhuman primates, the emergence of consciousness is intimately associated with the workings of the mammalian cerebral cortex with its specific cell types and layered structure. However, recent neurophysiological recordings demonstrate a neuronal correlate of consciousness in the pallial endbrain of crows. These telencephalic integration centers in birds originate embryonically from other pallial territories, lack a layered architecture characteristic for the cerebral cortex, and exhibit independently evolved pallial cell types. This argues that the mammalian cerebral cortex is not a prerequisite for consciousness to emerge in all vertebrates. Rather, it seems that the anatomical and physiological principles of the telencephalic pallium offer this structure as a brain substrate for consciousness to evolve independently across vertebrate phylogeny.
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Affiliation(s)
- Andreas Nieder
- Animal Physiology Unit, Institute of Neurobiology, University of Tübingen, Auf der Morgenstelle 28, 72076, Tübingen, Germany.
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29
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Castro L, Remund Wiger E, Wasserman E. Focusing and shifting attention in pigeon category learning. JOURNAL OF EXPERIMENTAL PSYCHOLOGY-ANIMAL LEARNING AND COGNITION 2021; 47:371-383. [PMID: 34618535 DOI: 10.1037/xan0000302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Adaptively and flexibly modifying one's behavior depending on the current demands of the situation is a hallmark of executive function. Here, we examined whether pigeons could flexibly shift their attention from one set of features that were relevant in one categorization task to another set of features that were relevant in a second categorization task. Critically, members of both sets of features were available on every training trial, thereby requiring that attention be adaptively deployed on a trial-by-trial basis based on contextual information. The pigeons not only learned to correctly categorize the stimuli but, as training progressed, they concentrated their pecks to the training stimuli (a proxy measure for attention) on those features that were relevant in a specific context. The pigeons selectively tracked the features that were relevant in Context 1-but were irrelevant in Context 2-and they selectively tracked the features that were relevant in Context 2-but were irrelevant in Context 1. This adept feature tracking requires disengaging attention from a previously relevant feature and shifting attention to a previously ignored feature on a trial-by-trial basis. Pigeons' adaptive and flexible performance provides strong empirical support for the involvement of focusing and shifting attention under exceptionally challenging training conditions. (PsycInfo Database Record (c) 2021 APA, all rights reserved).
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30
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Tosches MA. From Cell Types to an Integrated Understanding of Brain Evolution: The Case of the Cerebral Cortex. Annu Rev Cell Dev Biol 2021; 37:495-517. [PMID: 34416113 DOI: 10.1146/annurev-cellbio-120319-112654] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
With the discovery of the incredible diversity of neurons, Cajal and coworkers laid the foundation of modern neuroscience. Neuron types are not only structural units of nervous systems but also evolutionary units, because their identities are encoded in the genome. With the advent of high-throughput cellular transcriptomics, neuronal identities can be characterized and compared systematically across species. The comparison of neurons in mammals, reptiles, and birds indicates that the mammalian cerebral cortex is a mosaic of deeply conserved and recently evolved neuron types. Using the cerebral cortex as a case study, this review illustrates how comparing neuron types across species is key to reconciling observations on neural development, neuroanatomy, circuit wiring, and physiology for an integrated understanding of brain evolution.
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31
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Güntürkün O, von Eugen K, Packheiser J, Pusch R. Avian pallial circuits and cognition: A comparison to mammals. Curr Opin Neurobiol 2021; 71:29-36. [PMID: 34562800 DOI: 10.1016/j.conb.2021.08.007] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 08/23/2021] [Accepted: 08/25/2021] [Indexed: 12/27/2022]
Abstract
Cognitive functions are similar in birds and mammals. So, are therefore pallial cellular circuits and neuronal computations also alike? In search of answers, we move in from bird's pallial connectomes, to cortex-like sensory canonical circuits and connections, to forebrain micro-circuitries and finally to the avian "prefrontal" area. This voyage from macro- to micro-scale networks and areas reveals that both birds and mammals evolved similar neural and computational properties in either convergent or parallel manner, based upon circuitries inherited from common ancestry. Thus, these two vertebrate classes evolved separately within 315 million years with highly similar pallial architectures that produce comparable cognitive functions.
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Affiliation(s)
- Onur Güntürkün
- Department of Biopsychology, Institute of Cognitive Neuroscience, Faculty of Psychology, Ruhr University Bochum, Universitätsstraße 150, 44801, Bochum, Germany.
| | - Kaya von Eugen
- Department of Biopsychology, Institute of Cognitive Neuroscience, Faculty of Psychology, Ruhr University Bochum, Universitätsstraße 150, 44801, Bochum, Germany
| | - Julian Packheiser
- Department of Biopsychology, Institute of Cognitive Neuroscience, Faculty of Psychology, Ruhr University Bochum, Universitätsstraße 150, 44801, Bochum, Germany
| | - Roland Pusch
- Department of Biopsychology, Institute of Cognitive Neuroscience, Faculty of Psychology, Ruhr University Bochum, Universitätsstraße 150, 44801, Bochum, Germany
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32
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Mallatt J, Feinberg TE. Multiple Routes to Animal Consciousness: Constrained Multiple Realizability Rather Than Modest Identity Theory. Front Psychol 2021; 12:732336. [PMID: 34630245 PMCID: PMC8497802 DOI: 10.3389/fpsyg.2021.732336] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 08/13/2021] [Indexed: 11/13/2022] Open
Abstract
The multiple realizability thesis (MRT) is an important philosophical and psychological concept. It says any mental state can be constructed by multiple realizability (MR), meaning in many distinct ways from different physical parts. The goal of our study is to find if the MRT applies to the mental state of consciousness among animals. Many things have been written about MRT but the ones most applicable to animal consciousness are by Shapiro in a 2004 book called The Mind Incarnate and by Polger and Shapiro in their 2016 work, The Multiple Realization Book. Standard, classical MRT has been around since 1967 and it says that a mental state can have very many different physical realizations, in a nearly unlimited manner. To the contrary, Shapiro's book reasoned that physical, physiological, and historical constraints force mental traits to evolve in just a few, limited directions, which is seen as convergent evolution of the associated neural traits in different animal lineages. This is his mental constraint thesis (MCT). We examined the evolution of consciousness in animals and found that it arose independently in just three animal clades-vertebrates, arthropods, and cephalopod mollusks-all of which share many consciousness-associated traits: elaborate sensory organs and brains, high capacity for memory, directed mobility, etc. These three constrained, convergently evolved routes to consciousness fit Shapiro's original MCT. More recently, Polger and Shapiro's book presented much the same thesis but changed its name from MCT to a "modest identity thesis." Furthermore, they argued against almost all the classically offered instances of MR in animal evolution, especially against the evidence of neural plasticity and the differently expanded cerebrums of mammals and birds. In contrast, we argue that some of these classical examples of MR are indeed valid and that Shapiro's original MCT correction of MRT is the better account of the evolution of consciousness in animal clades. And we still agree that constraints and convergence refute the standard, nearly unconstrained, MRT.
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Affiliation(s)
- Jon Mallatt
- The University of Washington WWAMI Medical Education Program at The University of Idaho, Moscow, ID, United States
| | - Todd E Feinberg
- Department of Psychiatry and Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, United States
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33
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Kabelik D, Julien AR, Ramirez D, O'Connell LA. Social boldness correlates with brain gene expression in male green anoles. Horm Behav 2021; 133:105007. [PMID: 34102460 PMCID: PMC8277760 DOI: 10.1016/j.yhbeh.2021.105007] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Revised: 05/01/2021] [Accepted: 05/22/2021] [Indexed: 11/27/2022]
Abstract
Within populations, some individuals tend to exhibit a bold or shy social behavior phenotype relative to the mean. The neural underpinnings of these differing phenotypes - also described as syndromes, personalities, and coping styles - is an area of ongoing investigation. Although a social decision-making network has been described across vertebrate taxa, most studies examining activity within this network do so in relation to exhibited differences in behavioral expression. Our study instead focuses on constitutive gene expression in bold and shy individuals by isolating baseline gene expression profiles that influence social boldness predisposition, rather than those reflecting the results of social interaction and behavioral execution. We performed this study on male green anole lizards (Anolis carolinensis), an established model organism for behavioral research, which provides a crucial comparison group to investigations of birds and mammals. After identifying subjects as bold or shy through repeated reproductive and agonistic behavior testing, we used RNA sequencing to compare gene expression profiles between these groups within various forebrain, midbrain, and hindbrain regions. The ventromedial hypothalamus had the largest group differences in gene expression, with bold males having increased expression of neuroendocrine and neurotransmitter receptor and calcium channel genes compared to shy males. Conversely, shy males express more integrin alpha-10 in the majority of examined regions. There were no significant group differences in physiology or hormone levels. Our results highlight the ventromedial hypothalamus as an important center of behavioral differences across individuals and provide novel candidates for investigations into the regulation of individual variation in social behavior phenotype.
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Affiliation(s)
- David Kabelik
- Department of Biology & Program in Neuroscience, Rhodes College, Memphis, TN 38112, USA.
| | - Allison R Julien
- Department of Biology & Program in Neuroscience, Rhodes College, Memphis, TN 38112, USA
| | - Dave Ramirez
- Department of Biology, Stanford University, Stanford, CA 94305, USA
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Nomura T, Ohtaka-Maruyama C, Kiyonari H, Gotoh H, Ono K. Changes in Wnt-Dependent Neuronal Morphology Underlie the Anatomical Diversification of Neocortical Homologs in Amniotes. Cell Rep 2021; 31:107592. [PMID: 32375034 DOI: 10.1016/j.celrep.2020.107592] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 02/13/2020] [Accepted: 04/09/2020] [Indexed: 10/24/2022] Open
Abstract
The six-layered neocortex is a shared characteristic of all mammals, but not of non-mammalian species, and its formation requires an inside-out pattern of neuronal migration. The extant reptilian dorsal cortex is thought to represent an ancestral form of the neocortex, although how the reptilian three-layered cortex is formed is poorly understood. Here, we show unique patterns of lamination and neuronal migration in the developing reptilian cortex. While the multipolar-to-bipolar transition of migrating neurons is essential for mammalian cortical development, the reptilian cortex lacks bipolar-shaped migrating neurons, resulting in an outside-in pattern of cortical development. Furthermore, dynamic regulation of Wnt signal strengths contributes to neuronal morphological changes, which is conserved across species. Our data preclude the idea that the six-layered mammalian neocortex emerged by simple addition to the reptilian dorsal cortex but suggest that the acquisition of a novel neuronal morphology based on conserved developmental programs contributed to neocortical evolution.
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Affiliation(s)
- Tadashi Nomura
- Developmental Neurobiology, Kyoto Prefectural University of Medicine, INAMORI Memorial Building, 1-5 Shimogamo-Hangi cho, Sakyoku, Kyoto 606-0823, Japan.
| | - Chiaki Ohtaka-Maruyama
- Neural Network Project, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya-ku, Tokyo 156-8506, Japan
| | - Hiroshi Kiyonari
- Laboratory for Animal Resources and Genetic Engineering, RIKEN Center for Biosystems Dynamics Research, 2-2-3 Minatojima Minamimachi, Chuo-ku, Kobe 650-0047, Japan
| | - Hitoshi Gotoh
- Developmental Neurobiology, Kyoto Prefectural University of Medicine, INAMORI Memorial Building, 1-5 Shimogamo-Hangi cho, Sakyoku, Kyoto 606-0823, Japan
| | - Katsuhiko Ono
- Developmental Neurobiology, Kyoto Prefectural University of Medicine, INAMORI Memorial Building, 1-5 Shimogamo-Hangi cho, Sakyoku, Kyoto 606-0823, Japan
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35
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Gedman G, Haase B, Durieux G, Biegler MT, Fedrigo O, Jarvis ED. As above, so below: Whole transcriptome profiling demonstrates strong molecular similarities between avian dorsal and ventral pallial subdivisions. J Comp Neurol 2021; 529:3222-3246. [PMID: 33871048 PMCID: PMC8251894 DOI: 10.1002/cne.25159] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [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: 12/19/2022]
Abstract
Over the last two decades, beginning with the Avian Brain Nomenclature Forum in 2000, major revisions have been made to our understanding of the organization and nomenclature of the avian brain. However, there are still unresolved questions on avian pallial organization, particularly whether the cells above the vestigial ventricle represent distinct populations to those below it or similar populations. To test these two hypotheses, we profiled the transcriptomes of the major avian pallial subdivisions dorsal and ventral to the vestigial ventricle boundary using RNA sequencing and a new zebra finch genome assembly containing about 22,000 annotated, complete genes. We found that the transcriptomes of neural populations above and below the ventricle were remarkably similar. Each subdivision in dorsal pallium (Wulst) had a corresponding molecular counterpart in the ventral pallium (dorsal ventricular ridge). In turn, each corresponding subdivision exhibited shared gene co‐expression modules that contained gene sets enriched in functional specializations, such as anatomical structure development, synaptic transmission, signaling, and neurogenesis. These findings are more in line with the continuum hypothesis of avian brain subdivision organization above and below the vestigial ventricle space, with the pallium as a whole consisting of four major cell populations (intercalated pallium, mesopallium, hyper‐nidopallium, and arcopallium) instead of seven (hyperpallium apicale, interstitial hyperpallium apicale, intercalated hyperpallium, hyperpallium densocellare, mesopallium, nidopallium, and arcopallium). We suggest adopting a more streamlined hierarchical naming system that reflects the robust similarities in gene expression, neural connectivity motifs, and function. These findings have important implications for our understanding of overall vertebrate brain evolution.
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Affiliation(s)
- Gregory Gedman
- Laboratory of the Neurogenetics of Language, The Rockefeller University, New York, New York, USA
| | - Bettina Haase
- Laboratory of the Neurogenetics of Language, The Rockefeller University, New York, New York, USA.,Vertebrate Genome Laboratory, The Rockefeller University, New York, New York, USA
| | - Gillian Durieux
- Behavioural Genomics, Max Planck Institute for Evolutionary Biology, Plön, Germany
| | - Matthew T Biegler
- Laboratory of the Neurogenetics of Language, The Rockefeller University, New York, New York, USA
| | - Olivier Fedrigo
- Laboratory of the Neurogenetics of Language, The Rockefeller University, New York, New York, USA.,Vertebrate Genome Laboratory, The Rockefeller University, New York, New York, USA
| | - Erich D Jarvis
- Laboratory of the Neurogenetics of Language, The Rockefeller University, New York, New York, USA.,Vertebrate Genome Laboratory, The Rockefeller University, New York, New York, USA.,Howard Hughes Medical Institute, Chevy Chase, Maryland, USA
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36
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Le Merre P, Ährlund-Richter S, Carlén M. The mouse prefrontal cortex: Unity in diversity. Neuron 2021; 109:1925-1944. [PMID: 33894133 DOI: 10.1016/j.neuron.2021.03.035] [Citation(s) in RCA: 101] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Revised: 01/28/2021] [Accepted: 03/29/2021] [Indexed: 12/11/2022]
Abstract
The prefrontal cortex (PFC) is considered to constitute the highest stage of neural integration and to be devoted to representation and production of actions. Studies in primates have laid the foundation for theories regarding the principles of prefrontal function and provided mechanistic insights. The recent surge of studies of the PFC in mice holds promise for evolvement of present theories and development of novel concepts, particularly regarding principles shared across mammals. Here we review recent empirical work on the mouse PFC capitalizing on the experimental toolbox currently privileged to studies in this species. We conclude that this line of research has revealed cellular and structural distinctions of the PFC and neuronal activity with direct relevance to theories regarding the functions of the PFC. We foresee that data-rich mouse studies will be key to shed light on the general prefrontal architecture and mechanisms underlying cognitive aspects of organized actions.
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Affiliation(s)
- Pierre Le Merre
- Department of Neuroscience, Karolinska Institutet, 171 77 Stockholm, Sweden
| | | | - Marie Carlén
- Department of Neuroscience, Karolinska Institutet, 171 77 Stockholm, Sweden; Department of Biosciences and Nutrition, Karolinska Institutet, 141 83 Huddinge, Sweden.
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37
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Ferrari R, Grandi N, Tramontano E, Dieci G. Retrotransposons as Drivers of Mammalian Brain Evolution. Life (Basel) 2021; 11:life11050376. [PMID: 33922141 PMCID: PMC8143547 DOI: 10.3390/life11050376] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 04/20/2021] [Accepted: 04/21/2021] [Indexed: 12/11/2022] Open
Abstract
Retrotransposons, a large and diverse class of transposable elements that are still active in humans, represent a remarkable force of genomic innovation underlying mammalian evolution. Among the features distinguishing mammals from all other vertebrates, the presence of a neocortex with a peculiar neuronal organization, composition and connectivity is perhaps the one that, by affecting the cognitive abilities of mammals, contributed mostly to their evolutionary success. Among mammals, hominids and especially humans display an extraordinarily expanded cortical volume, an enrichment of the repertoire of neural cell types and more elaborate patterns of neuronal connectivity. Retrotransposon-derived sequences have recently been implicated in multiple layers of gene regulation in the brain, from transcriptional and post-transcriptional control to both local and large-scale three-dimensional chromatin organization. Accordingly, an increasing variety of neurodevelopmental and neurodegenerative conditions are being recognized to be associated with retrotransposon dysregulation. We review here a large body of recent studies lending support to the idea that retrotransposon-dependent evolutionary novelties were crucial for the emergence of mammalian, primate and human peculiarities of brain morphology and function.
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Affiliation(s)
- Roberto Ferrari
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy;
| | - Nicole Grandi
- Laboratory of Molecular Virology, Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria di Monserrato, 09042 Monserrato, Italy; (N.G.); (E.T.)
| | - Enzo Tramontano
- Laboratory of Molecular Virology, Department of Life and Environmental Sciences, University of Cagliari, Cittadella Universitaria di Monserrato, 09042 Monserrato, Italy; (N.G.); (E.T.)
- Istituto di Ricerca Genetica e Biomedica, Consiglio Nazionale delle Ricerche, 09042 Monserrato, Italy
| | - Giorgio Dieci
- Department of Chemistry, Life Sciences and Environmental Sustainability, University of Parma, 43124 Parma, Italy;
- Correspondence:
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38
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Abstract
Many species from diverse and often distantly related animal groups (e.g. monkeys, crows, fish and bees) have a sense of number. This means that they can assess the number of items in a set - its 'numerosity'. The brains of these phylogenetically distant species are markedly diverse. This Review examines the fundamentally different types of brains and neural mechanisms that give rise to numerical competence across the animal tree of life. Neural correlates of the number sense so far exist only for specific vertebrate species: the richest data concerning explicit and abstract number representations have been collected from the cerebral cortex of mammals, most notably human and nonhuman primates, but also from the pallium of corvid songbirds, which evolved independently of the mammalian cortex. In contrast, the neural data relating to implicit and reflexive numerical representations in amphibians and fish is limited. The neural basis of a number sense has not been explored in any protostome so far. However, promising candidate regions in the brains of insects, spiders and cephalopods - all of which are known to have number skills - are identified in this Review. A comparative neuroscientific approach will be indispensable for identifying evolutionarily stable neuronal circuits and deciphering codes that give rise to a sense of number across phylogeny.
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Affiliation(s)
- Andreas Nieder
- Animal Physiology Unit, Institute of Neurobiology, University of Tübingen, Auf der Morgenstelle 28, 72076 Tübingen, Germany
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39
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Colquitt BM, Merullo DP, Konopka G, Roberts TF, Brainard MS. Cellular transcriptomics reveals evolutionary identities of songbird vocal circuits. Science 2021; 371:371/6530/eabd9704. [PMID: 33574185 DOI: 10.1126/science.abd9704] [Citation(s) in RCA: 106] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 12/07/2020] [Indexed: 12/13/2022]
Abstract
Birds display advanced behaviors, including vocal learning and problem-solving, yet lack a layered neocortex, a structure associated with complex behavior in mammals. To determine whether these behavioral similarities result from shared or distinct neural circuits, we used single-cell RNA sequencing to characterize the neuronal repertoire of the songbird song motor pathway. Glutamatergic vocal neurons had considerable transcriptional similarity to neocortical projection neurons; however, they displayed regulatory gene expression patterns more closely related to neurons in the ventral pallium. Moreover, while γ-aminobutyric acid-releasing neurons in this pathway appeared homologous to those in mammals and other amniotes, the most abundant avian class is largely absent in the neocortex. These data suggest that songbird vocal circuits and the mammalian neocortex have distinct developmental origins yet contain transcriptionally similar neurons.
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Affiliation(s)
- Bradley M Colquitt
- Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.,Departments of Physiology and Psychiatry, University of California-San Francisco, San Francisco, CA 94158, USA
| | - Devin P Merullo
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Genevieve Konopka
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
| | - Todd F Roberts
- Department of Neuroscience, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
| | - Michael S Brainard
- Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA. .,Departments of Physiology and Psychiatry, University of California-San Francisco, San Francisco, CA 94158, USA
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40
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Neural Code of Motor Planning and Execution during Goal-Directed Movements in Crows. J Neurosci 2021; 41:4060-4072. [PMID: 33608384 DOI: 10.1523/jneurosci.0739-20.2021] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 01/19/2021] [Accepted: 01/28/2021] [Indexed: 11/21/2022] Open
Abstract
The planning and execution of head-beak movements are vital components of bird behavior. They require integration of sensory input and internal processes with goal-directed motor output. Despite its relevance, the neurophysiological mechanisms underlying action planning and execution outside of the song system are largely unknown. We recorded single-neuron activity from the associative endbrain area nidopallium caudolaterale (NCL) of two male carrion crows (Corvus corone) trained to plan and execute head-beak movements in a spatial delayed response task. The crows were instructed to plan an impending movement toward one of eight possible targets on the left or right side of a touchscreen. In a fraction of trials, the crows were prompted to plan a movement toward a self-chosen target. NCL neurons signaled the impending motion direction in instructed trials. Tuned neuronal activity during motor planning categorically represented the target side, but also specific target locations. As a marker of intentional movement preparation, neuronal activity reliably predicted both target side and specific target location when the crows were free to select a target. In addition, NCL neurons were tuned to specific target locations during movement execution. A subset of neurons was tuned during both planning and execution period; these neurons experienced a sharpening of spatial tuning with the transition from planning to execution. These results show that the avian NCL not only represents high-level sensory and cognitive task components, but also transforms behaviorally-relevant information into dynamic action plans and motor execution during the volitional perception-action cycle of birds.SIGNIFICANCE STATEMENT Corvid songbirds have become exciting new models for understanding complex cognitive behavior. As a key neural underpinning, the endbrain area nidopallium caudolaterale (NCL) represents sensory and memory-related task components. How such representations are converted into goal-directed motor output remained unknown. In crows, we report that NCL neurons are involved in the planning and execution of goal-directed movements. NCL neurons prospectively signaled motion directions in instructed trials, but also when the crows were free to choose a target. NCL neurons showed a target-specific sharpening of tuning with the transition from the planning to the execution period. Thus, the avian NCL not only represents high-level sensory and cognitive task components, but also transforms relevant information into action plans and motor execution.
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41
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Affiliation(s)
- Maria Antonietta Tosches
- Department of Biological Sciences, Columbia University, 1212 Amsterdam Avenue, New York, NY 10027, USA
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42
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Exner CRT, Willsey HR. Xenopus leads the way: Frogs as a pioneering model to understand the human brain. Genesis 2021; 59:e23405. [PMID: 33369095 PMCID: PMC8130472 DOI: 10.1002/dvg.23405] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 12/12/2020] [Accepted: 12/14/2020] [Indexed: 12/20/2022]
Abstract
From its long history in the field of embryology to its recent advances in genetics, Xenopus has been an indispensable model for understanding the human brain. Foundational studies that gave us our first insights into major embryonic patterning events serve as a crucial backdrop for newer avenues of investigation into organogenesis and organ function. The vast array of tools available in Xenopus laevis and Xenopus tropicalis allows interrogation of developmental phenomena at all levels, from the molecular to the behavioral, and the application of CRISPR technology has enabled the investigation of human disorder risk genes in a higher-throughput manner. As the only major tetrapod model in which all developmental stages are easily manipulated and observed, frogs provide the unique opportunity to study organ development from the earliest stages. All of these features make Xenopus a premier model for studying the development of the brain, a notoriously complex process that demands an understanding of all stages from fertilization to organogenesis and beyond. Importantly, core processes of brain development are conserved between Xenopus and human, underlining the advantages of this model. This review begins by summarizing discoveries made in amphibians that form the cornerstones of vertebrate neurodevelopmental biology and goes on to discuss recent advances that have catapulted our understanding of brain development in Xenopus and in relation to human development and disease. As we engage in a new era of patient-driven gene discovery, Xenopus offers exceptional potential to uncover conserved biology underlying human brain disorders and move towards rational drug design.
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Affiliation(s)
- Cameron R T Exner
- Department of Psychiatry and Behavioral Sciences, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, California, 94143, USA
| | - Helen Rankin Willsey
- Department of Psychiatry and Behavioral Sciences, UCSF Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, California, 94143, USA
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43
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Tejeda HA, Wang H, Flores RJ, Yarur HE. Dynorphin/Kappa-Opioid Receptor System Modulation of Cortical Circuitry. Handb Exp Pharmacol 2021; 271:223-253. [PMID: 33580392 DOI: 10.1007/164_2021_440] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Cortical circuits control a plethora of behaviors, from sensation to cognition. The cortex is enriched with neuropeptides and receptors that play a role in information processing, including opioid peptides and their cognate receptors. The dynorphin (DYN)/kappa-opioid receptor (KOR) system has been implicated in the processing of sensory and motivationally-charged emotional information and is highly expressed in cortical circuits. This is important as dysregulation of DYN/KOR signaling in limbic and cortical circuits has been implicated in promoting negative affect and cognitive deficits in various neuropsychiatric disorders. However, research investigating the role of this system in controlling cortical circuits and computations therein is limited. Here, we review the (1) basic anatomy of cortical circuits, (2) anatomical architecture of the cortical DYN/KOR system, (3) functional regulation of cortical synaptic transmission and microcircuit function by the DYN/KOR system, (4) regulation of behavior by the cortical DYN/KOR system, (5) implications for the DYN/KOR system for human health and disease, and (6) future directions and unanswered questions for the field. Further work elucidating the role of the DYN/KOR system in controlling cortical information processing and associated behaviors will be of importance to increasing our understanding of principles underlying neuropeptide modulation of cortical circuits, mechanisms underlying sensation and perception, motivated and emotional behavior, and cognition. Increased emphasis in this area of study will also aid in the identification of novel ways to target the DYN/KOR system to treat neuropsychiatric disorders.
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Affiliation(s)
- Hugo A Tejeda
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA.
| | - Huikun Wang
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Rodolfo J Flores
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Hector E Yarur
- Unit on Neuromodulation and Synaptic Integration, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
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44
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Manka SW, Moores CA. Pseudo-repeats in doublecortin make distinct mechanistic contributions to microtubule regulation. EMBO Rep 2020; 21:e51534. [PMID: 33051979 PMCID: PMC7726794 DOI: 10.15252/embr.202051534] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 09/17/2020] [Accepted: 09/18/2020] [Indexed: 11/16/2022] Open
Abstract
Doublecortin (DCX) is a neuronal microtubule-associated protein (MAP) indispensable for brain development. Its flexibly linked doublecortin (DC) domains-NDC and CDC-mediate microtubule (MT) nucleation and stabilization, but it is unclear how. Using high-resolution time-resolved cryo-EM, we mapped NDC and CDC interactions with tubulin at different MT polymerization stages and studied their functional effects on MT dynamics using TIRF microscopy. Although coupled, each DC repeat within DCX appears to have a distinct role in MT nucleation and stabilization: CDC is a conformationally plastic module that appears to facilitate MT nucleation and stabilize tubulin-tubulin contacts in the nascent MT lattice, while NDC appears to be favored along the mature lattice, providing MT stabilization. Our structures of MT-bound DC domains also explain in unprecedented detail the DCX mutation-related brain defects observed in the clinic. This modular composition of DCX reflects a common design principle among MAPs where pseudo-repeats of tubulin/MT binding elements chaperone or stabilize distinct conformational transitions to regulate distinct stages of MT dynamic instability.
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Affiliation(s)
- Szymon W Manka
- Institute of Structural and Molecular BiologyDepartment of Biological Sciences, BirkbeckUniversity of LondonLondonUK
| | - Carolyn A Moores
- Institute of Structural and Molecular BiologyDepartment of Biological Sciences, BirkbeckUniversity of LondonLondonUK
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45
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Abstract
To survive, animals need to adapt to changes of their ecosystem by changing their behaviors or even morphing the organs responsible for generating these behaviors. Small mammals have a high metabolic rate, and to balance energy deficits during winter they can decrease their brain and body size, a phenomenon termed Dehnel’s effect. We find specific seasonal changes in the brain of the smallest terrestrial mammal, the Etruscan shrew. Their cortex shrinks in the winter, with layer-width and neuron number reduction in the energetically expensive somatosensory cortical layer 4. Imaging of neural activity revealed reduced suppressive responses to whisker touch during winter, indicating that such cortical adaptation may have synergistic functional and behavioral effects in addition to direct metabolic benefits. Seasonal cycles govern life on earth, from setting the time for the mating season to influencing migrations and governing physiological conditions like hibernation. The effect of such changing conditions on behavior is well-appreciated, but their impact on the brain remains virtually unknown. We investigate long-term seasonal changes in the mammalian brain, known as Dehnel’s effect, where animals exhibit plasticity in body and brain sizes to counter metabolic demands in winter. We find large seasonal variation in cellular architecture and neuronal activity in the smallest terrestrial mammal, the Etruscan shrew, Suncus etruscus. Their brain, and specifically their neocortex, shrinks in winter. Shrews are tactile hunters, and information from whiskers first reaches the somatosensory cortex layer 4, which exhibits a reduced width (−28%) in winter. Layer 4 width (+29%) and neuron number (+42%) increase the following summer. Activity patterns in the somatosensory cortex show a prominent reduction of touch-suppressed neurons in layer 4 (−55%), the most metabolically active layer. Loss of inhibitory gating occurs with a reduction in parvalbumin-positive interneurons, one of the most active neuronal subtypes and the main regulators of inhibition in layer 4. Thus, a reduction in neurons in layer 4 and particularly parvalbumin-positive interneurons may incur direct metabolic benefits. However, changes in cortical balance can also affect the threshold for detecting sensory stimuli and impact prey choice, as observed in wild shrews. Thus, seasonal neural adaptation can offer synergistic metabolic and behavioral benefits to the organism and offer insights on how neural systems show adaptive plasticity in response to ecological demands.
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46
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Lin Y, Yang J, Shen Z, Ma J, Simons BD, Shi SH. Behavior and lineage progression of neural progenitors in the mammalian cortex. Curr Opin Neurobiol 2020; 66:144-157. [PMID: 33227588 DOI: 10.1016/j.conb.2020.10.017] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 10/19/2020] [Accepted: 10/22/2020] [Indexed: 12/17/2022]
Abstract
The cerebral cortex is a central structure in the mammalian brain that enables higher cognitive functions and intellectual skills. It is the hallmark of the mammalian nervous system with enormous complexity, consisting of a large number of neurons and glia that are diverse in morphology, molecular expression, biophysical properties, circuit connectivity and physiological function. Cortical neurons and glia are generated by neural progenitor cells during development. Ensuring the correct cell cycle kinetics, fate behavior and lineage progression of neural progenitor cells is essential to determine the number and types of neurons and glia in the cerebral cortex, which together constitute neural circuits for brain function. In this review, we discuss recent findings on mammalian cortical progenitor cell types and their lineage behaviors in generating neurons and glia, cortical evolution and expansion, and advances in brain organoid technology that allow the modeling of human cortical development under normal and disease conditions.
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Affiliation(s)
- Yang Lin
- IDG/McGovern Institute for Brain Research, Tsinghua-Peking Center for Life Sciences, Beijing Frontier Research Center of Biological Structure, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Jiajun Yang
- IDG/McGovern Institute for Brain Research, Tsinghua-Peking Center for Life Sciences, Beijing Frontier Research Center of Biological Structure, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Zhongfu Shen
- IDG/McGovern Institute for Brain Research, Tsinghua-Peking Center for Life Sciences, Beijing Frontier Research Center of Biological Structure, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Jian Ma
- IDG/McGovern Institute for Brain Research, Tsinghua-Peking Center for Life Sciences, Beijing Frontier Research Center of Biological Structure, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Benjamin D Simons
- The Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK; Department of Applied Mathematics and Theoretical Physics, Centre for Mathematical Sciences, Wilberforce Road, Cambridge CB3 0WA, UK
| | - Song-Hai Shi
- IDG/McGovern Institute for Brain Research, Tsinghua-Peking Center for Life Sciences, Beijing Frontier Research Center of Biological Structure, Beijing Advanced Innovation Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China.
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47
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García-Moreno F, Molnár Z. Variations of telencephalic development that paved the way for neocortical evolution. Prog Neurobiol 2020; 194:101865. [PMID: 32526253 PMCID: PMC7656292 DOI: 10.1016/j.pneurobio.2020.101865] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 05/29/2020] [Accepted: 06/05/2020] [Indexed: 12/13/2022]
Abstract
Charles Darwin stated, "community in embryonic structure reveals community of descent". Thus, to understand how the neocortex emerged during mammalian evolution we need to understand the evolution of the development of the pallium, the source of the neocortex. In this article, we review the variations in the development of the pallium that enabled the production of the six-layered neocortex. We propose that an accumulation of subtle modifications from very early brain development accounted for the diversification of vertebrate pallia and the origin of the neocortex. Initially, faint differences of expression of secretable morphogens promote a wide variety in the proportions and organization of sectors of the early pallium in different vertebrates. It prompted different sectors to host varied progenitors and distinct germinative zones. These cells and germinative compartments generate diverse neuronal populations that migrate and mix with each other through radial and tangential migrations in a taxon-specific fashion. Together, these early variations had a profound influence on neurogenetic gradients, lamination, positioning, and connectivity. Gene expression, hodology, and physiological properties of pallial neurons are important features to suggest homologies, but the origin of cells and their developmental trajectory are fundamental to understand evolutionary changes. Our review compares the development of the homologous pallial sectors in sauropsids and mammals, with a particular focus on cell lineage, in search of the key changes that led to the appearance of the mammalian neocortex.
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Affiliation(s)
- Fernando García-Moreno
- Achucarro Basque Center for Neuroscience, Scientific Park of the University of the Basque Country (UPV/EHU), 48940, Leioa, Spain; IKERBASQUE Foundation, María Díaz de Haro 3, 6th Floor, 48013, Bilbao, Spain; Department of Neuroscience, Faculty of Medicine and Odontology, UPV/EHU, Barrio Sarriena s/n, 48940, Leioa, Bizkaia, Spain.
| | - Zoltán Molnár
- Department of Physiology, Anatomy and Genetics, Sherrington Building, University of Oxford, Oxford, OX1 3QX, UK.
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48
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Comparative Perspectives that Challenge Brain Warming as the Primary Function of REM Sleep. iScience 2020; 23:101696. [PMID: 33196022 PMCID: PMC7644584 DOI: 10.1016/j.isci.2020.101696] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 09/17/2020] [Accepted: 10/14/2020] [Indexed: 01/04/2023] Open
Abstract
Rapid eye movement (REM) sleep is a paradoxical state of wake-like brain activity occurring after non-REM (NREM) sleep in mammals and birds. In mammals, brain cooling during NREM sleep is followed by warming during REM sleep, potentially preparing the brain to perform adaptively upon awakening. If brain warming is the primary function of REM sleep, then it should occur in other animals with similar states. We measured cortical temperature in pigeons and bearded dragons, lizards that exhibit NREM-like sleep and REM-like sleep with brain activity resembling wakefulness. In pigeons, cortical temperature decreased during NREM sleep and increased during REM sleep. However, brain temperature did not increase when dragons switched from NREM-like to REM-like sleep. Our findings indicate that brain warming is not a universal outcome of sleep states characterized by wake-like activity, challenging the hypothesis that their primary function is to warm the brain in preparation for wakefulness. In many mammals, the brain cools during non-REM sleep and warms during REM sleep Pigeons exhibit similar changes in cortical temperature during non-REM and REM sleep Brain temperature does not increase during REM-like sleep in bearded dragon lizards Brain warming is not a universal outcome of sleep states with wake-like brain activity
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49
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Stacho M, Herold C, Rook N, Wagner H, Axer M, Amunts K, Güntürkün O. A cortex-like canonical circuit in the
avian forebrain. Science 2020; 369:369/6511/eabc5534. [DOI: 10.1126/science.abc5534] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 08/13/2020] [Indexed: 12/15/2022]
Abstract
Although the avian pallium seems to lack
an organization akin to that of the cerebral
cortex, birds exhibit extraordinary cognitive
skills that are comparable to those of mammals. We
analyzed the fiber architecture of the avian
pallium with three-dimensional polarized light
imaging and subsequently reconstructed local and
associative pallial circuits with tracing
techniques. We discovered an iteratively repeated,
column-like neuronal circuitry across the
layer-like nuclear boundaries of the hyperpallium
and the sensory dorsal ventricular ridge. These
circuits are connected to neighboring columns and,
via tangential layer-like connections, to higher
associative and motor areas. Our findings indicate
that this avian canonical circuitry is similar to
its mammalian counterpart and might constitute the
structural basis of neuronal computation.
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Affiliation(s)
- Martin Stacho
- Department of Biopsychology,
Institute of Cognitive Neuroscience, Faculty of
Psychology, Ruhr-University Bochum, 44801 Bochum,
Germany
- Department of Neurophysiology,
Institute of Physiology, Faculty of Medicine,
Ruhr-University Bochum, 44801 Bochum,
Germany
| | - Christina Herold
- Cécile and Oskar Vogt Institute for
Brain Research, Medical Faculty, Heinrich Heine
University of Düsseldorf, 40225 Düsseldorf,
Germany
| | - Noemi Rook
- Department of Biopsychology,
Institute of Cognitive Neuroscience, Faculty of
Psychology, Ruhr-University Bochum, 44801 Bochum,
Germany
| | - Hermann Wagner
- Institute for Biology II, RWTH Aachen
University, 52074 Aachen, Germany
| | - Markus Axer
- Institute of Neuroscience and
Medicine INM-1, Research Center Jülich, 52425
Jülich, Germany
| | - Katrin Amunts
- Cécile and Oskar Vogt Institute for
Brain Research, Medical Faculty, Heinrich Heine
University of Düsseldorf, 40225 Düsseldorf,
Germany
- Institute of Neuroscience and
Medicine INM-1, Research Center Jülich, 52425
Jülich, Germany
| | - Onur Güntürkün
- Department of Biopsychology,
Institute of Cognitive Neuroscience, Faculty of
Psychology, Ruhr-University Bochum, 44801 Bochum,
Germany
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Abstract
AbstractEvolution of adaptation requires predictability and recurrence of functional contexts. Yet organisms live in multifaceted environments that are dynamic and ever changing, making it difficult to understand how complex adaptations evolve. This problem is particularly apparent in the evolution of adaptive maternal effects, which are often assumed to require reliable and discrete cues that predict conditions in the offspring environment. One resolution to this problem is if adaptive maternal effects evolve through preexisting, generalized maternal pathways that respond to many cues and also influence offspring development. Here, we assess whether an adaptive maternal effect in western bluebirds is influenced by maternal stress pathways across multiple challenging environments. Combining 18 years of hormone sampling across diverse environmental contexts with an experimental manipulation of the competitive environment, we show that multiple environmental factors influenced maternal corticosterone levels, which, in turn, influenced a maternal effect on aggression of sons in adulthood. Together, these results support the idea that multiple stressors can induce a known maternal effect in this system. More generally, they suggest that activation of general pathways, such as the hypothalamic-pituitary-adrenal axis, may simplify and facilitate the evolution of adaptive maternal effects by integrating variable environmental conditions into preexisting maternal physiological systems.
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