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Schuff M, Strong AD, Welborn LK, Ziermann-Canabarro JM. Imprinting as Basis for Complex Evolutionary Novelties in Eutherians. BIOLOGY 2024; 13:682. [PMID: 39336109 PMCID: PMC11428813 DOI: 10.3390/biology13090682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2024] [Revised: 08/24/2024] [Accepted: 08/28/2024] [Indexed: 09/30/2024]
Abstract
The epigenetic phenomenon of genomic imprinting is puzzling. While epigenetic modifications in general are widely known in most species, genomic imprinting in the animal kingdom is restricted to autosomes of therian mammals, mainly eutherians, and to a lesser extent in marsupials. Imprinting causes monoallelic gene expression. It represents functional haploidy of certain alleles while bearing the evolutionary cost of diploidization, which is the need of a complex cellular architecture and the danger of producing aneuploid cells by mitotic and meiotic errors. The parent-of-origin gene expression has stressed many theories. Most prominent theories, such as the kinship (parental conflict) hypothesis for maternally versus paternally derived alleles, explain only partial aspects of imprinting. The implementation of single-cell transcriptome analyses and epigenetic research allowed detailed study of monoallelic expression in a spatial and temporal manner and demonstrated a broader but much more complex and differentiated picture of imprinting. In this review, we summarize all these aspects but argue that imprinting is a functional haploidy that not only allows a better gene dosage control of critical genes but also increased cellular diversity and plasticity. Furthermore, we propose that only the occurrence of allele-specific gene regulation mechanisms allows the appearance of evolutionary novelties such as the placenta and the evolutionary expansion of the eutherian brain.
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Affiliation(s)
- Maximillian Schuff
- Next Fertility St. Gallen, Kürsteinerstrasse 2, 9015 St. Gallen, Switzerland
| | - Amanda D Strong
- Department of Anatomy, Howard University College of Medicine, 520 W St. NW, Washington, DC 20059, USA
| | - Lyvia K Welborn
- Department of Anatomy, Howard University College of Medicine, 520 W St. NW, Washington, DC 20059, USA
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2
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Glangetas C, Guillaumin A, Ladevèze E, Braine A, Gauthier M, Bonamy L, Doudnikoff E, Dhellemmes T, Landry M, Bézard E, Caille S, Taupignon A, Baufreton J, Georges F. A population of Insula neurons encodes for social preference only after acute social isolation in mice. Nat Commun 2024; 15:7142. [PMID: 39164260 PMCID: PMC11336167 DOI: 10.1038/s41467-024-51389-4] [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: 12/20/2022] [Accepted: 08/05/2024] [Indexed: 08/22/2024] Open
Abstract
The Insula functions as a multisensory relay involved in socio-emotional processing with projections to sensory, cognitive, emotional, and motivational regions. Notably, the interhemispheric projection from the Insula to the contralateral Insula is a robust yet underexplored connection. Using viral-based tracing neuroanatomy, ex vivo and in vivo electrophysiology, in vivo fiber photometry along with targeted circuit manipulation, we elucidated the nature and role of InsulaIns communication in social and anxiety processing in mice. In this study, we 1) characterized the anatomical and molecular profile of the InsulaIns neurons, 2) demonstrated that stimulation of this neuronal subpopulation induces excitation in the Insula interhemispheric circuit, 3) revealed that InsulaIns neurons are essential for social discrimination after 24 h of isolation in male mice. In conclusion, our findings highlight InsulaIns neurons as a distinct class of neurons within the insula and offer new insights into the neuronal mechanisms underlying social behavior.
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Affiliation(s)
| | | | | | | | - Manon Gauthier
- Univ. Bordeaux, CNRS, IMN, Bordeaux, France
- Univ. Poitiers, Inserm, LNEC, Poitiers, France
| | - Léa Bonamy
- Univ. Bordeaux, CNRS, IMN, Bordeaux, France
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3
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Mahon S. Variation and convergence in the morpho-functional properties of the mammalian neocortex. Front Syst Neurosci 2024; 18:1413780. [PMID: 38966330 PMCID: PMC11222651 DOI: 10.3389/fnsys.2024.1413780] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2024] [Accepted: 06/03/2024] [Indexed: 07/06/2024] Open
Abstract
Man's natural inclination to classify and hierarchize the living world has prompted neurophysiologists to explore possible differences in brain organisation between mammals, with the aim of understanding the diversity of their behavioural repertoires. But what really distinguishes the human brain from that of a platypus, an opossum or a rodent? In this review, we compare the structural and electrical properties of neocortical neurons in the main mammalian radiations and examine their impact on the functioning of the networks they form. We discuss variations in overall brain size, number of neurons, length of their dendritic trees and density of spines, acknowledging their increase in humans as in most large-brained species. Our comparative analysis also highlights a remarkable consistency, particularly pronounced in marsupial and placental mammals, in the cell typology, intrinsic and synaptic electrical properties of pyramidal neuron subtypes, and in their organisation into functional circuits. These shared cellular and network characteristics contribute to the emergence of strikingly similar large-scale physiological and pathological brain dynamics across a wide range of species. These findings support the existence of a core set of neural principles and processes conserved throughout mammalian evolution, from which a number of species-specific adaptations appear, likely allowing distinct functional needs to be met in a variety of environmental contexts.
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Affiliation(s)
- Séverine Mahon
- Sorbonne Université, Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, APHP, Hôpital de la Pitié Salpêtrière, Paris, France
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4
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Ocklenburg S, Guo ZV. Cross-hemispheric communication: Insights on lateralized brain functions. Neuron 2024; 112:1222-1234. [PMID: 38458199 DOI: 10.1016/j.neuron.2024.02.010] [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: 07/31/2023] [Revised: 12/13/2023] [Accepted: 02/12/2024] [Indexed: 03/10/2024]
Abstract
On the surface, the two hemispheres of vertebrate brains look almost perfectly symmetrical, but several motor, sensory, and cognitive systems show a deeply lateralized organization. Importantly, the two hemispheres are connected by various commissures, white matter tracts that cross the brain's midline and enable cross-hemispheric communication. Cross-hemispheric communication has been suggested to play an important role in the emergence of lateralized brain functions. Here, we review current advances in understanding cross-hemispheric communication that have been made using modern neuroscientific tools in rodents and other model species, such as genetic labeling, large-scale recordings of neuronal activity, spatiotemporally precise perturbation, and quantitative behavior analyses. These findings suggest that the emergence of lateralized brain functions cannot be fully explained by largely static factors such as genetic variation and differences in structural brain asymmetries. In addition, learning-dependent asymmetric interactions between the left and right hemispheres shape lateralized brain functions.
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Affiliation(s)
- Sebastian Ocklenburg
- Department of Psychology, MSH Medical School Hamburg, Hamburg, Germany; ICAN Institute for Cognitive and Affective Neuroscience, MSH Medical School Hamburg, Hamburg, Germany; Biopsychology, Institute of Cognitive Neuroscience, Faculty of Psychology, Ruhr University Bochum, Bochum, Germany.
| | - Zengcai V Guo
- School of Medicine, Tsinghua University, Beijing 100084, China; Tsinghua-Peking Joint Center for Life Sciences, Beijing 100084, China; IDG/McGovern Institute for Brain Research, Tsinghua University, Beijing 100084, China.
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5
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Kitazawa M. Evolution of the nervous system by acquisition of retrovirus-derived genes in mammals. Genes Genet Syst 2024; 98:321-336. [PMID: 38220159 DOI: 10.1266/ggs.23-00197] [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] [Indexed: 01/16/2024] Open
Abstract
In the course of evolution, the most highly developed organ is likely the brain, which has become more complex over time and acquired diverse forms and functions in different species. In particular, mammals have developed complex and high-functioning brains, and it has been reported that several genes derived from retroviruses were involved in mammalian brain evolution, that is, generating the complexity of the nervous system. Especially, the sushi-ichi-related retrotransposon homolog (SIRH)/retrotransposon gag-like (RTL) genes have been suggested to play a role in the evolutionary processes shaping brain morphology and function in mammals. Genetic mutation and altered expression of genes are linked to neurological disorders, highlighting how the acquisition of virus-derived genes in mammals has both driven brain evolution and imposed a susceptibility to diseases. This review provides an overview of the functions, diversity, evolution and diseases associated with SIRH/RTL genes in the nervous system. The contribution of retroviruses to brain evolution is an important research topic in evolutionary biology and neuroscience, and further insights are expected to be gained through future studies.
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Affiliation(s)
- Moe Kitazawa
- School of BioSciences, Faculty of Science, The University of Melbourne
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6
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Szczupak D, Schaeffer DJ, Tian X, Choi SH, Fang-Cheng, Iack PM, Campos VP, Mayo JP, Patsch J, Mitter C, Haboosheh A, Kwon HS, Vieira MAC, Reich DS, Jacobson S, Kasprian G, Tovar-Moll F, Lent R, Silva AC. Direct interhemispheric cortical communication via thalamic commissures: a new white matter pathway in the primate brain. Cereb Cortex 2024; 34:bhad394. [PMID: 37950874 PMCID: PMC10793074 DOI: 10.1093/cercor/bhad394] [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: 06/15/2023] [Revised: 10/02/2023] [Accepted: 10/03/2023] [Indexed: 11/13/2023] Open
Abstract
Cortical neurons of eutherian mammals project to the contralateral hemisphere, crossing the midline primarily via the corpus callosum and the anterior, posterior, and hippocampal commissures. We recently reported and named the thalamic commissures (TCs) as an additional interhemispheric axonal fiber pathway connecting the cortex to the contralateral thalamus in the rodent brain. Here, we demonstrate that TCs also exist in primates and characterize the connectivity of these pathways with high-resolution diffusion-weighted MRI, viral axonal tracing, and fMRI. We present evidence of TCs in both New World (Callithrix jacchus and Cebus apella) and Old World primates (Macaca mulatta). Further, like rodents, we show that the TCs in primates develop during the embryonic period, forming anatomical and functionally active connections of the cortex with the contralateral thalamus. We also searched for TCs in the human brain, showing their presence in humans with brain malformations, although we could not identify TCs in healthy subjects. These results pose the TCs as a vital fiber pathway in the primate brain, allowing for more robust interhemispheric connectivity and synchrony and serving as an alternative commissural route in developmental brain malformations.
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Affiliation(s)
- Diego Szczupak
- University of Pittsburgh Brain Institute, Department of Neurobiology, University of Pittsburgh, 3501 Fifth Avenue, Pittsburgh, PA 15261, USA
| | - David J Schaeffer
- University of Pittsburgh Brain Institute, Department of Neurobiology, University of Pittsburgh, 3501 Fifth Avenue, Pittsburgh, PA 15261, USA
| | - Xiaoguang Tian
- University of Pittsburgh Brain Institute, Department of Neurobiology, University of Pittsburgh, 3501 Fifth Avenue, Pittsburgh, PA 15261, USA
| | - Sang-Ho Choi
- University of Pittsburgh Brain Institute, Department of Neurobiology, University of Pittsburgh, 3501 Fifth Avenue, Pittsburgh, PA 15261, USA
| | - Fang-Cheng
- Department of Neurological Surgery, University of Pittsburgh, 200 Lothrop Street, Pittsburgh, PA 15261, USA
| | - Pamela Meneses Iack
- Biomedical Sciences Institute, Federal University of Rio de Janeiro, 373 Carlos Chagas Filho Avenue, Rio de Janeiro, Rio de Janeiro 21941-853, Brazil
| | - Vinicius P Campos
- Department of Electrical and Computer Engineering, 400 Trabalhador São-Carlense Avenue, University of São Paulo, São Carlos, SP 13565-905, Brazil
| | - J Patrick Mayo
- Department of Ophthalmology, University of Pittsburgh, 1622 Locust Street, Pittsburgh, PA 15261, USA
| | - Janina Patsch
- Department of Biomedical Imaging and Image-Guided Therapy of the Medical University of Vienna, 18-20 Währinger Gürtel, 1090, Vienna, Austria
| | - Christian Mitter
- Department of Biomedical Imaging and Image-Guided Therapy of the Medical University of Vienna, 18-20 Währinger Gürtel, 1090, Vienna, Austria
| | - Amit Haboosheh
- Department of Radiology Hadassah Ein Karem Hospital, Kalman Ya'akov Man St, Jerusalem 9112001, Israel
| | - Ha Seung Kwon
- University of Pittsburgh Brain Institute, Department of Neurobiology, University of Pittsburgh, 3501 Fifth Avenue, Pittsburgh, PA 15261, USA
| | - Marcelo A C Vieira
- Department of Electrical and Computer Engineering, 400 Trabalhador São-Carlense Avenue, University of São Paulo, São Carlos, SP 13565-905, Brazil
| | - Daniel S Reich
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, 10 Center Drive, Bethesda, MD 20814, USA
| | - Steve Jacobson
- National Institute of Neurological Disorders and Stroke, National Institutes of Health, 10 Center Drive, Bethesda, MD 20814, USA
| | - Gregor Kasprian
- Department of Biomedical Imaging and Image-Guided Therapy of the Medical University of Vienna, 18-20 Währinger Gürtel, 1090, Vienna, Austria
| | - Fernanda Tovar-Moll
- D’Or Institute of Research and Education, 30 Rua Diniz Cordeiro Street, Rio de Janeiro, Rio de Janeiro 22281-100, Brazil
| | - Roberto Lent
- Biomedical Sciences Institute, Federal University of Rio de Janeiro, 373 Carlos Chagas Filho Avenue, Rio de Janeiro, Rio de Janeiro 21941-853, Brazil
- D’Or Institute of Research and Education, 30 Rua Diniz Cordeiro Street, Rio de Janeiro, Rio de Janeiro 22281-100, Brazil
| | - Afonso C Silva
- University of Pittsburgh Brain Institute, Department of Neurobiology, University of Pittsburgh, 3501 Fifth Avenue, Pittsburgh, PA 15261, USA
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7
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Molnár Z, Kwan KY. Development and Evolution of Thalamocortical Connectivity. Cold Spring Harb Perspect Biol 2024; 16:a041503. [PMID: 38167425 PMCID: PMC10759993 DOI: 10.1101/cshperspect.a041503] [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: 01/05/2024]
Abstract
Conscious perception in mammals depends on precise circuit connectivity between cerebral cortex and thalamus; the evolution and development of these structures are closely linked. During the wiring of reciprocal thalamus-cortex connections, thalamocortical axons (TCAs) first navigate forebrain regions that had undergone substantial evolutionary modifications. In particular, the organization of the pallial-subpallial boundary (PSPB) diverged significantly between mammals, reptiles, and birds. In mammals, transient cell populations in internal capsule and early corticofugal projections from subplate neurons closely interact with TCAs to guide pathfinding through ventral forebrain and PSPB crossing. Prior to thalamocortical axon arrival, cortical areas are initially patterned by intrinsic genetic factors. Thalamocortical axons then innervate cortex in a topographically organized manner to enable sensory input to refine cortical arealization. Here, we review the mechanisms underlying the guidance of thalamocortical axons across forebrain boundaries, the implications of PSPB evolution for thalamocortical axon pathfinding, and the reciprocal influence between thalamus and cortex during development.
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Affiliation(s)
- Zoltán Molnár
- Department of Physiology, Anatomy and Genetics, Sherrington Building, University of Oxford, Oxford OX1 3PT, United Kingdom
| | - Kenneth Y Kwan
- Michigan Neuroscience Institute (MNI), Department of Human Genetics, University of Michigan, Ann Arbor, Michigan 48109, USA
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8
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Dumitru ML. Brain asymmetry is globally different in males and females: exploring cortical volume, area, thickness, and mean curvature. Cereb Cortex 2023; 33:11623-11633. [PMID: 37851852 PMCID: PMC10724869 DOI: 10.1093/cercor/bhad396] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 10/02/2023] [Accepted: 10/03/2023] [Indexed: 10/20/2023] Open
Abstract
Brain asymmetry is a cornerstone in the development of higher-level cognition, but it is unclear whether and how it differs in males and females. Asymmetry has been investigated using the laterality index, which compares homologous regions as pairwise weighted differences between the left and the right hemisphere. However, if asymmetry differences between males and females are global instead of pairwise, involving proportions between multiple brain areas, novel methodological tools are needed to evaluate them. Here, we used the Amsterdam Open MRI collection to investigate sexual dimorphism in brain asymmetry by comparing laterality index with the distance index, which is a global measure of differences within and across hemispheres, and with the subtraction index, which compares pairwise raw values in the left and right hemisphere. Machine learning models, robustness tests, and group analyses of cortical volume, area, thickness, and mean curvature revealed that, of the three indices, distance index was the most successful biomarker of sexual dimorphism. These findings suggest that left-right asymmetry in males and females involves global coherence rather than pairwise contrasts. Further studies are needed to investigate the biological basis of local and global asymmetry based on growth patterns under genetic, hormonal, and environmental factors.
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Affiliation(s)
- Magda L Dumitru
- Department of Biological Sciences, University of Bergen, Postboks 7803, 5020 Bergen, Norway
- Department of Biological and Medical Psychology, University of Bergen, Postboks 7807, 5020 Bergen, Norway
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9
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Lynton Z, Suárez R, Fenlon LR. Brain plasticity following corpus callosum agenesis or loss: a review of the Probst bundles. Front Neuroanat 2023; 17:1296779. [PMID: 38020213 PMCID: PMC10657877 DOI: 10.3389/fnana.2023.1296779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2023] [Accepted: 10/11/2023] [Indexed: 12/01/2023] Open
Abstract
The corpus callosum is the largest axonal tract in the human brain, connecting the left and right cortical hemipheres. This structure is affected in myriad human neurodevelopmental disorders, and can be entirely absent as a result of congenital or surgical causes. The age when callosal loss occurs, for example via surgical section in cases of refractory epilepsy, correlates with resulting brain morphology and neuropsychological outcomes, whereby an earlier loss generally produces relatively improved interhemispheric connectivity compared to a loss in adulthood (known as the "Sperry's paradox"). However, the mechanisms behind these age-dependent differences remain unclear. Perhaps the best documented and most striking of the plastic changes that occur due to developmental, but not adult, callosal loss is the formation of large, bilateral, longitudinal ectopic tracts termed Probst bundles. Despite over 100 years of research into these ectopic tracts, which are the largest and best described stereotypical ectopic brain tracts in humans, much remains unclear about them. Here, we review the anatomy of the Probst bundles, along with evidence for their faciliatory or detrimental function, the required conditions for their formation, patterns of etiology, and mechanisms of development. We provide hypotheses for many of the remaining mysteries of the Probst bundles, including their possible relationship to preserved interhemispheric communication following corpus callosum absence. Future research into naturally occurring plastic tracts such as Probst bundles will help to inform the general rules governing axon plasticity and disorders of brain miswiring.
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Affiliation(s)
- Zorana Lynton
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St Lucia, QLD, Australia
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia
| | - Rodrigo Suárez
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St Lucia, QLD, Australia
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia
| | - Laura R. Fenlon
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, St Lucia, QLD, Australia
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia
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10
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Paolino A, Haines EH, Bailey EJ, Black DA, Moey C, García-Moreno F, Richards LJ, Suárez R, Fenlon LR. Non-uniform temporal scaling of developmental processes in the mammalian cortex. Nat Commun 2023; 14:5950. [PMID: 37741828 PMCID: PMC10517946 DOI: 10.1038/s41467-023-41652-5] [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: 06/09/2023] [Accepted: 09/13/2023] [Indexed: 09/25/2023] Open
Abstract
The time that it takes the brain to develop is highly variable across animals. Although staging systems equate major developmental milestones between mammalian species, it remains unclear how distinct processes of cortical development scale within these timeframes. Here, we compare the timing of cortical development in two mammals of similar size but different developmental pace: eutherian mice and marsupial fat-tailed dunnarts. Our results reveal that the temporal relationship between cell birth and laminar specification aligns to equivalent stages between these species, but that migration and axon extension do not scale uniformly according to the developmental stages, and are relatively more advanced in dunnarts. We identify a lack of basal intermediate progenitor cells in dunnarts that likely contributes in part to this timing difference. These findings demonstrate temporal limitations and differential plasticity of cortical developmental processes between similarly sized Therians and provide insight into subtle temporal changes that may have contributed to the early diversification of the mammalian brain.
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Affiliation(s)
- Annalisa Paolino
- The University of Queensland, School of Biomedical Sciences, Brisbane, QLD 4072, Australia
- The University of Queensland, Queensland Brain Institute, Brisbane, QLD 4072, Australia
| | - Elizabeth H Haines
- The University of Queensland, School of Biomedical Sciences, Brisbane, QLD 4072, Australia
- The University of Queensland, Queensland Brain Institute, Brisbane, QLD 4072, Australia
| | - Evan J Bailey
- The University of Queensland, School of Biomedical Sciences, Brisbane, QLD 4072, Australia
- The University of Queensland, Queensland Brain Institute, Brisbane, QLD 4072, Australia
| | - Dylan A Black
- The University of Queensland, Queensland Brain Institute, Brisbane, QLD 4072, Australia
| | - Ching Moey
- The University of Queensland, Queensland Brain Institute, Brisbane, QLD 4072, Australia
| | - 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, 48013, Bilbao, Spain
| | - Linda J Richards
- The University of Queensland, School of Biomedical Sciences, Brisbane, QLD 4072, Australia
- The University of Queensland, Queensland Brain Institute, Brisbane, QLD 4072, Australia
- Washington University in St Louis School of Medicine, Department of Neuroscience, St Louis, MO, 63108, USA
| | - Rodrigo Suárez
- The University of Queensland, School of Biomedical Sciences, Brisbane, QLD 4072, Australia.
- The University of Queensland, Queensland Brain Institute, Brisbane, QLD 4072, Australia.
| | - Laura R Fenlon
- The University of Queensland, School of Biomedical Sciences, Brisbane, QLD 4072, Australia.
- The University of Queensland, Queensland Brain Institute, Brisbane, QLD 4072, Australia.
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11
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Haines E, Bailey E, Nelson J, Fenlon LR, Suárez R. Clade-specific forebrain cytoarchitectures of the extinct Tasmanian tiger. Proc Natl Acad Sci U S A 2023; 120:e2306516120. [PMID: 37523567 PMCID: PMC10410726 DOI: 10.1073/pnas.2306516120] [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: 04/21/2023] [Accepted: 05/23/2023] [Indexed: 08/02/2023] Open
Abstract
The thylacine, or Tasmanian tiger, is the largest of modern-day carnivorous marsupials and was hunted to extinction by European settlers in Australia. Its physical resemblance to eutherian wolves is a striking example of evolutionary convergence to similar ecological niches. However, whether the neuroanatomical organization of the thylacine brain resembles that of canids and how it compares with other mammals remain unknown due to the scarcity of available samples. Here, we gained access to a century-old hematoxylin-stained histological series of a thylacine brain, digitalized it at high resolution, and compared its forebrain cellular architecture with 34 extant species of monotremes, marsupials, and eutherians. Phylogenetically informed comparisons of cortical folding, regional volumes, and cell sizes and densities across cortical areas and layers provide evidence against brain convergences with canids, instead demonstrating features typical of marsupials, and more specifically Dasyuridae, along with traits that scale similarly with brain size across mammals. Enlarged olfactory, limbic, and neocortical areas suggest a small-prey predator and/or scavenging lifestyle, similar to extant quolls and Tasmanian devils. These findings are consistent with a nonuniformity of trait convergences, with brain traits clustering more with phylogeny and head/body traits with lifestyle. By making this resource publicly available as rapid web-accessible, hierarchically organized, multiresolution images for perpetuity, we anticipate that additional comparative insights might arise from detailed studies of the thylacine brain and encourage researchers and curators to share, annotate, and preserve understudied material of outstanding biological relevance.
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Affiliation(s)
- Elizabeth Haines
- School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, QLD4072, Australia
- Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, QLD4072, Australia
| | - Evan Bailey
- School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, QLD4072, Australia
- Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, QLD4072, Australia
| | - John Nelson
- School of Biological Sciences, Monash University, Melbourne, Victoria, VIC3800, Australia
| | - Laura R. Fenlon
- School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, QLD4072, Australia
- Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, QLD4072, Australia
| | - Rodrigo Suárez
- School of Biomedical Sciences, The University of Queensland, Brisbane, Queensland, QLD4072, Australia
- Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, QLD4072, Australia
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12
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Szczupak D, Schaeffer DJ, Tian X, Choi SH, Fang-Cheng, Iack PM, Campos VP, Mayo JP, Patsch J, Mitter C, Haboosheh A, Vieira MA, Kasprian G, Tovar-Moll F, Lent R, Silva AC. Direct interhemispheric cortical communication via thalamic commissures: a new white-matter pathway in the primate brain. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.15.545128. [PMID: 37398056 PMCID: PMC10312754 DOI: 10.1101/2023.06.15.545128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Cortical neurons of eutherian mammals project to the contralateral hemisphere, crossing the midline primarily via the corpus callosum and the anterior, posterior, and hippocampal commissures. We recently reported an additional commissural pathway in rodents, termed the thalamic commissures (TCs), as another interhemispheric axonal fiber pathway that connects cortex to the contralateral thalamus. Here, we demonstrate that TCs also exist in primates and characterize the connectivity of these pathways with high-resolution diffusion-weighted magnetic resonance imaging, viral axonal tracing, and functional MRI. We present evidence of TCs in both New World (Callithrix jacchus and Cebus apella) and Old World primates (Macaca mulatta). Further, like rodents, we show that the TCs in primates develop during the embryonic period, forming anatomical and functionally active connections of the cortex with the contralateral thalamus. We also searched for TCs in the human brain, showing their presence in humans with brain malformations, although we could not identify TCs in healthy subjects. These results pose the TCs as an important fiber pathway in the primate brain, allowing for more robust interhemispheric connectivity and synchrony and serving as an alternative commissural route in developmental brain malformations.
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Affiliation(s)
- Diego Szczupak
- University of Pittsburgh Brain Institute, Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - David J. Schaeffer
- University of Pittsburgh Brain Institute, Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Xiaoguang Tian
- University of Pittsburgh Brain Institute, Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Sang-Ho Choi
- University of Pittsburgh Brain Institute, Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Fang-Cheng
- Department of Neurological Surgery University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Pamela Meneses Iack
- Department of Neurological Surgery University of Pittsburgh, Pittsburgh, PA 15261, USA
| | | | - J. Patrick Mayo
- Department of Electrical and Computer Engineering, University of São Paulo, São Carlos, SP 13565-905, Brazil
| | - Janina Patsch
- Department of Biomedical Imaging and Image-guided therapy of the Medical University of Vienna, 1090, Austria
| | - Christian Mitter
- Department of Biomedical Imaging and Image-guided therapy of the Medical University of Vienna, 1090, Austria
| | - Amit Haboosheh
- Department Of Radiology Hadassah Ein Karem Hospital, Jerusalem 9112001, Israel
| | - Marcelo A.C. Vieira
- Department of Electrical and Computer Engineering, University of São Paulo, São Carlos, SP 13565-905, Brazil
| | - Gregor Kasprian
- Department of Biomedical Imaging and Image-guided therapy of the Medical University of Vienna, 1090, Austria
| | | | - Roberto Lent
- Federal University of Rio de Janeiro, Rio de Janeiro 21941-853, Brazil
- D’Or Institute of Research and Education, Rio de Janeiro 22281-100, Brazil
| | - Afonso C. Silva
- University of Pittsburgh Brain Institute, Department of Neurobiology, University of Pittsburgh, Pittsburgh, PA 15261, USA
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13
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Suárez R, Bluett T, McCullough MH, Avitan L, Black DA, Paolino A, Fenlon LR, Goodhill GJ, Richards LJ. Cortical activity emerges in region-specific patterns during early brain development. Proc Natl Acad Sci U S A 2023; 120:e2208654120. [PMID: 37216522 PMCID: PMC10235933 DOI: 10.1073/pnas.2208654120] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Accepted: 04/17/2023] [Indexed: 05/24/2023] Open
Abstract
The development of precise neural circuits in the brain requires spontaneous patterns of neural activity prior to functional maturation. In the rodent cerebral cortex, patchwork and wave patterns of activity develop in somatosensory and visual regions, respectively, and are present at birth. However, whether such activity patterns occur in noneutherian mammals, as well as when and how they arise during development, remain open questions relevant for understanding brain formation in health and disease. Since the onset of patterned cortical activity is challenging to study prenatally in eutherians, here we offer an approach in a minimally invasive manner using marsupial dunnarts, whose cortex forms postnatally. We discovered similar patchwork and travelling waves in the dunnart somatosensory and visual cortices at stage 27 (equivalent to newborn mice) and examined earlier stages of development to determine the onset of these patterns and how they first emerge. We observed that these patterns of activity emerge in a region-specific and sequential manner, becoming evident as early as stage 24 in somatosensory and stage 25 in visual cortices (equivalent to embryonic day 16 and 17, respectively, in mice), as cortical layers establish and thalamic axons innervate the cortex. In addition to sculpting synaptic connections of existing circuits, evolutionarily conserved patterns of neural activity could therefore help regulate other early events in cortical development.
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Affiliation(s)
- Rodrigo Suárez
- The University of Queensland, Queensland Brain Institute, BrisbaneQLD4072, Australia
- The University of Queensland, School of Biomedical Sciences, BrisbaneQLD4072, Australia
| | - Tobias Bluett
- The University of Queensland, Queensland Brain Institute, BrisbaneQLD4072, Australia
| | - Michael H. McCullough
- The University of Queensland, Queensland Brain Institute, BrisbaneQLD4072, Australia
| | - Lilach Avitan
- The University of Queensland, Queensland Brain Institute, BrisbaneQLD4072, Australia
| | - Dylan A. Black
- The University of Queensland, Queensland Brain Institute, BrisbaneQLD4072, Australia
- The University of Queensland, School of Biomedical Sciences, BrisbaneQLD4072, Australia
| | - Annalisa Paolino
- The University of Queensland, Queensland Brain Institute, BrisbaneQLD4072, Australia
- The University of Queensland, School of Biomedical Sciences, BrisbaneQLD4072, Australia
| | - Laura R. Fenlon
- The University of Queensland, Queensland Brain Institute, BrisbaneQLD4072, Australia
- The University of Queensland, School of Biomedical Sciences, BrisbaneQLD4072, Australia
| | - Geoffrey J. Goodhill
- The University of Queensland, Queensland Brain Institute, BrisbaneQLD4072, Australia
- The University of Queensland, School of Mathematics and Physics, BrisbaneQLD4072, Australia
| | - Linda J. Richards
- The University of Queensland, Queensland Brain Institute, BrisbaneQLD4072, Australia
- The University of Queensland, School of Biomedical Sciences, BrisbaneQLD4072, Australia
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14
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Szczupak D, Lent R, Tovar-Moll F, Silva AC. Heterotopic connectivity of callosal dysgenesis in mice and humans. Front Neurosci 2023; 17:1191859. [PMID: 37274193 PMCID: PMC10232863 DOI: 10.3389/fnins.2023.1191859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 05/02/2023] [Indexed: 06/06/2023] Open
Abstract
The corpus callosum (CC), the largest brain commissure and the primary white matter pathway for interhemispheric cortical connectivity, was traditionally viewed as a predominantly homotopic structure, connecting mirror areas of the cortex. However, new studies verified that most callosal commissural fibers are heterotopic. Recently, we reported that ~75% of the callosal connections in the brains of mice, marmosets, and humans are heterotopic, having an essential role in determining the global properties of brain networks. In the present study, we leveraged high-resolution diffusion-weighted imaging and graph network modeling to investigate the relationship between heterotopic and homotopic callosal fibers in human subjects and in a spontaneous mouse model of Corpus Callosum Dysgenesis (CCD), a congenital developmental CC malformation that leads to widespread whole-brain reorganization. Our results show that the CCD brain is more heterotopic than the normotypical brain, with both mouse and human CCD subjects displaying highly variable heterotopicity maps. CCD mice have a clear heterotopicity cluster in the anterior CC, while hypoplasic humans have strongly variable patterns. Graph network-based connectivity profile showed a direct impact of heterotopic connections on CCD brains altering several network-based statistics. Our collective results show that CCD directly alters heterotopic connections and brain connectivity.
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Affiliation(s)
- Diego Szczupak
- Department of Neurobiology, University of Pittsburgh Brain Institute, University of Pittsburgh, Pittsburgh, PA, United States
| | - Roberto Lent
- Institute of Biomedical Sciences, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
- D’Or Institute Research and Education (IDOR), Rio de Janeiro, Brazil
| | | | - Afonso C. Silva
- Department of Neurobiology, University of Pittsburgh Brain Institute, University of Pittsburgh, Pittsburgh, PA, United States
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15
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Ocklenburg S, El Basbasse Y, Ströckens F, Müller-Alcazar A. Hemispheric asymmetries and brain size in mammals. Commun Biol 2023; 6:521. [PMID: 37188844 PMCID: PMC10185570 DOI: 10.1038/s42003-023-04894-z] [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: 12/16/2022] [Accepted: 05/02/2023] [Indexed: 05/17/2023] Open
Abstract
Hemispheric asymmetries differ considerably across species, but the neurophysiological base of this variation is unclear. It has been suggested that hemispheric asymmetries evolved to bypass interhemispheric conduction delay when performing time-critical tasks. This implies that large brains should be more asymmetric. We performed preregistered cross-species meta-regressions with brain mass and neuron number as predictors for limb preferences, a behavioral marker of hemispheric asymmetries, in mammals. Brain mass and neuron number showed positive associations with rightward limb preferences but negative associations with leftward limb preferences. No significant associations were found for ambilaterality. These results are only partly in line with the idea that conduction delay is the critical factor that drives the evolution of hemispheric asymmetries. They suggest that larger-brained species tend to shift towards more right-lateralized individuals. Therefore, the need for coordination of lateralized responses in social species needs to be considered in the context of the evolution of hemispheric asymmetries.
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Affiliation(s)
- Sebastian Ocklenburg
- Department of Psychology, MSH Medical School Hamburg, Hamburg, Germany.
- Institute for Cognitive and Affective Neuroscience, MSH Medical School Hamburg, Hamburg, Germany.
- Biopsychology, Institute for Cognitive Neuroscience, Ruhr University Bochum, Bochum, Germany.
| | - Yasmin El Basbasse
- Biopsychology, Institute for Cognitive Neuroscience, Ruhr University Bochum, Bochum, Germany
| | - Felix Ströckens
- C. & O. Vogt Institute for Brain Research, University Hospital Düsseldorf, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| | - Anett Müller-Alcazar
- Department of Psychology, MSH Medical School Hamburg, Hamburg, Germany
- Institute for Cognitive and Affective Neuroscience, MSH Medical School Hamburg, Hamburg, Germany
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16
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Suárez R, Bluett T, McCullough MH, Avitan L, Black DA, Paolino A, Fenlon LR, Goodhill GJ, Richards LJ. Cortical activity emerges in region-specific patterns during early brain development. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.18.529078. [PMID: 36824827 PMCID: PMC9949140 DOI: 10.1101/2023.02.18.529078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
The development of precise neural circuits in the brain requires spontaneous patterns of neural activity prior to functional maturation. In the rodent cerebral cortex patchwork and wave patterns of activity develop in somatosensory and visual regions, respectively, and are present at birth. However, whether such activity patterns occur in non-eutherian mammals, as well as when and how they arise during development remain open questions relevant to understand brain formation in health and disease. Since the onset of patterned cortical activity is challenging to study prenatally in eutherians, here we offer a new approach in a minimally invasive manner using marsupial dunnarts, whose cortex forms postnatally. We discovered similar patchwork and travelling waves in the dunnart somatosensory and visual cortices at stage 27 (equivalent to newborn mice), and examined progressively earlier stages of development to determine their onset and how they first emerge. We observed that these patterns of activity emerge in a region-specific and sequential manner, becoming evident as early as stage 24 in somatosensory and stage 25 in visual cortices (equivalent to embryonic day 16 and 17, respectively, in mice), as cortical layers establish and thalamic axons innervate the cortex. In addition to sculpting synaptic connections of existing circuits, evolutionarily conserved patterns of neural activity could therefore help regulate early events in cortical development. Significance Statement Region-specific patterns of neural activity are present at birth in rodents and are thought to refine synaptic connections during critical periods of cerebral cortex development. Marsupials are born much more immature than rodents, allowing the investigation of how these patterns arise in vivo. We discovered that cortical activity patterns are remarkably similar in marsupial dunnarts and rodents, and that they emerge very early, before cortical neurogenesis is complete. Moreover, they arise from the outset in different patterns specific to somatosensory and visual areas (i.e., patchworks and waves) indicating they may also play evolutionarily conserved roles in cortical regionalization during development.
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Affiliation(s)
- Rodrigo Suárez
- The University of Queensland, Queensland Brain Institute; Brisbane, Australia
- The University of Queensland, School of Biomedical Sciences; Brisbane, Australia
| | - Tobias Bluett
- The University of Queensland, Queensland Brain Institute; Brisbane, Australia
| | | | - Lilach Avitan
- The University of Queensland, Queensland Brain Institute; Brisbane, Australia
| | - Dylan A. Black
- The University of Queensland, Queensland Brain Institute; Brisbane, Australia
- The University of Queensland, School of Biomedical Sciences; Brisbane, Australia
| | - Annalisa Paolino
- The University of Queensland, Queensland Brain Institute; Brisbane, Australia
- The University of Queensland, School of Biomedical Sciences; Brisbane, Australia
| | - Laura R. Fenlon
- The University of Queensland, Queensland Brain Institute; Brisbane, Australia
- The University of Queensland, School of Biomedical Sciences; Brisbane, Australia
| | - Geoffrey J. Goodhill
- The University of Queensland, Queensland Brain Institute; Brisbane, Australia
- The University of Queensland, School of Mathematics and Physics; Brisbane, Australia
| | - Linda J. Richards
- The University of Queensland, Queensland Brain Institute; Brisbane, Australia
- The University of Queensland, School of Biomedical Sciences; Brisbane, Australia
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17
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Szczupak D, Iack PM, Rayêe D, Liu C, Lent R, Tovar-Moll F, Silva AC. The relevance of heterotopic callosal fibers to interhemispheric connectivity of the mammalian brain. Cereb Cortex 2023; 33:4752-4760. [PMID: 36178137 PMCID: PMC10110439 DOI: 10.1093/cercor/bhac377] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 08/29/2022] [Accepted: 08/30/2022] [Indexed: 11/14/2022] Open
Abstract
The corpus callosum (CC) is the largest white matter structure and the primary pathway for interhemispheric brain communication. Investigating callosal connectivity is crucial to unraveling the brain's anatomical and functional organization in health and disease. Classical anatomical studies have characterized the bulk of callosal axonal fibers as connecting primarily homotopic cortical areas. Whenever detected, heterotopic callosal fibers were ascribed to altered sprouting and pruning mechanisms in neurodevelopmental diseases such as CC dysgenesis (CCD). We hypothesized that these heterotopic connections had been grossly underestimated due to their complex nature and methodological limitations. We used the Allen Mouse Brain Connectivity Atlas and high-resolution diffusion-weighted imaging to identify and quantify homotopic and heterotopic callosal connections in mice, marmosets, and humans. In all 3 species, we show that ~75% of interhemispheric callosal connections are heterotopic and comprise the central core of the CC, whereas the homotopic fibers lay along its periphery. We also demonstrate that heterotopic connections have an essential role in determining the global properties of brain networks. These findings reshape our view of the corpus callosum's role as the primary hub for interhemispheric brain communication, directly impacting multiple neuroscience fields investigating cortical connectivity, neurodevelopment, and neurodevelopmental disorders.
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Affiliation(s)
- Diego Szczupak
- Department of Neurobiology, University of Pittsburgh Brain Institute, University of Pittsburgh, Pittsburgh, PA 15261, United States
| | - Pamela Meneses Iack
- Institute of Biomedical Sciences, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro 21941-590, Brazil
| | - Danielle Rayêe
- Institute of Ophtalmology and Visual Sciences, Albert Einstein College of Medicine, NY 10461, United States
| | - Cirong Liu
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China
| | - Roberto Lent
- Institute of Biomedical Sciences, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro 21941-590, Brazil
- D’Or Institute Research and Education (IDOR), Rio de Janeiro 22281-100, Brazil
| | - Fernanda Tovar-Moll
- D’Or Institute Research and Education (IDOR), Rio de Janeiro 22281-100, Brazil
| | - Afonso C Silva
- Department of Neurobiology, University of Pittsburgh Brain Institute, University of Pittsburgh, Pittsburgh, PA 15261, United States
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18
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Lozano D, López JM, Jiménez S, Morona R, Ruíz V, Martínez A, Moreno N. Expression of SATB1 and SATB2 in the brain of bony fishes: what fish reveal about evolution. Brain Struct Funct 2023; 228:921-945. [PMID: 37002478 PMCID: PMC10147777 DOI: 10.1007/s00429-023-02632-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 03/15/2023] [Indexed: 04/03/2023]
Abstract
AbstractSatb1 and Satb2 belong to a family of homeodomain proteins with highly conserved functional and regulatory mechanisms and posttranslational modifications in evolution. However, although their distribution in the mouse brain has been analyzed, few data exist in other non-mammalian vertebrates. In the present study, we have analyzed in detail the sequence of SATB1 and SATB2 proteins and the immunolocalization of both, in combination with additional neuronal markers of highly conserved populations, in the brain of adult specimens of different bony fish models at key evolutionary points of vertebrate diversification, in particular including representative species of sarcopterygian and actinopterygian fishes. We observed a striking absence of both proteins in the pallial region of actinopterygians, only detected in lungfish, the only sarcopterygian fish. In the subpallium, including the amygdaloid complex, or comparable structures, we identified that the detected expressions of SATB1 and SATB2 have similar topologies in the studied models. In the caudal telencephalon, all models showed significant expression of SATB1 and SATB2 in the preoptic area, including the acroterminal domain of this region, where the cells were also dopaminergic. In the alar hypothalamus, all models showed SATB2 but not SATB1 in the subparaventricular area, whereas in the basal hypothalamus the cladistian species and the lungfish presented a SATB1 immunoreactive population in the tuberal hypothalamus, also labeled with SATB2 in the latter and colocalizing with the gen Orthopedia. In the diencephalon, all models, except the teleost fish, showed SATB1 in the prethalamus, thalamus and pretectum, whereas only lungfish showed also SATB2 in prethalamus and thalamus. At the midbrain level of actinopterygian fish, the optic tectum, the torus semicircularis and the tegmentum harbored populations of SATB1 cells, whereas lungfish housed SATB2 only in the torus and tegmentum. Similarly, the SATB1 expression in the rhombencephalic central gray and reticular formation was a common feature. The presence of SATB1 in the solitary tract nucleus is a peculiar feature only observed in non-teleost actinopterygian fishes. At these levels, none of the detected populations were catecholaminergic or serotonergic. In conclusion, the protein sequence analysis revealed a high degree of conservation of both proteins, especially in the functional domains, whereas the neuroanatomical pattern of SATB1 and SATB2 revealed significant differences between sarcopterygians and actinopterygians, and these divergences may be related to the different functional involvement of both in the acquisition of various neural phenotypes.
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Affiliation(s)
- Daniel Lozano
- Department of Cell Biology, Faculty of Biology, University Complutense, 28040, Madrid, Spain
| | - Jesús M López
- Department of Cell Biology, Faculty of Biology, University Complutense, 28040, Madrid, Spain
| | - Sara Jiménez
- Department of Cell Biology, Faculty of Biology, University Complutense, 28040, Madrid, Spain
| | - Ruth Morona
- Department of Cell Biology, Faculty of Biology, University Complutense, 28040, Madrid, Spain
| | - Víctor Ruíz
- Department of Cell Biology, Faculty of Biology, University Complutense, 28040, Madrid, Spain
| | - Ana Martínez
- Department of Cell Biology, Faculty of Biology, University Complutense, 28040, Madrid, Spain
| | - Nerea Moreno
- Department of Cell Biology, Faculty of Biology, University Complutense, 28040, Madrid, Spain.
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19
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Wang Q, Wang Y, Kuo HC, Xie P, Kuang X, Hirokawa KE, Naeemi M, Yao S, Mallory M, Ouellette B, Lesnar P, Li Y, Ye M, Chen C, Xiong W, Ahmadinia L, El-Hifnawi L, Cetin A, Sorensen SA, Harris JA, Zeng H, Koch C. Regional and cell-type-specific afferent and efferent projections of the mouse claustrum. Cell Rep 2023; 42:112118. [PMID: 36774552 PMCID: PMC10415534 DOI: 10.1016/j.celrep.2023.112118] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 12/17/2022] [Accepted: 01/30/2023] [Indexed: 02/13/2023] Open
Abstract
The claustrum (CLA) is a conspicuous subcortical structure interconnected with cortical and subcortical regions. Its regional anatomy and cell-type-specific connections in the mouse remain not fully determined. Using multimodal reference datasets, we confirmed the delineation of the mouse CLA as a single group of neurons embedded in the agranular insular cortex. We quantitatively investigated brain-wide inputs and outputs of CLA using bulk anterograde and retrograde viral tracing data and single neuron tracing data. We found that the prefrontal module has more cell types projecting to the CLA than other cortical modules, with layer 5 IT neurons predominating. We found nine morphological types of CLA principal neurons that topographically innervate functionally linked cortical targets, preferentially the midline cortical areas, secondary motor area, and entorhinal area. Together, this study provides a detailed wiring diagram of the cell-type-specific connections of the mouse CLA, laying a foundation for studying its functions at the cellular level.
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Affiliation(s)
- Quanxin Wang
- Allen Institute for Brain Science, Seattle, WA 98109, USA.
| | - Yun Wang
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Hsien-Chi Kuo
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Peng Xie
- Institute for Brain and Intelligence, Southeast University, Nanjing, Jiangsu, China
| | - Xiuli Kuang
- School of Optometry and Ophthalmology, Wenzhou Medical University, Wenzhou, Zhejiang 325000, China
| | | | - Maitham Naeemi
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Shenqin Yao
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Matt Mallory
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Ben Ouellette
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Phil Lesnar
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Yaoyao Li
- School of Optometry and Ophthalmology, Wenzhou Medical University, Wenzhou, Zhejiang 325000, China
| | - Min Ye
- School of Optometry and Ophthalmology, Wenzhou Medical University, Wenzhou, Zhejiang 325000, China
| | - Chao Chen
- School of Optometry and Ophthalmology, Wenzhou Medical University, Wenzhou, Zhejiang 325000, China
| | - Wei Xiong
- School of Optometry and Ophthalmology, Wenzhou Medical University, Wenzhou, Zhejiang 325000, China
| | | | | | - Ali Cetin
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | | | - Julie A Harris
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Hongkui Zeng
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Christof Koch
- Allen Institute for Brain Science, Seattle, WA 98109, USA.
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20
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Oligodendrocytes Prune Axons Containing α-Synuclein Aggregates In Vivo: Lewy Neurites as Precursors of Glial Cytoplasmic Inclusions in Multiple System Atrophy? Biomolecules 2023; 13:biom13020269. [PMID: 36830639 PMCID: PMC9953613 DOI: 10.3390/biom13020269] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 01/17/2023] [Accepted: 01/30/2023] [Indexed: 02/04/2023] Open
Abstract
α-Synucleinopathies are spreading neurodegenerative disorders characterized by the intracellular accumulation of insoluble aggregates populated by α-Synuclein (α-Syn) fibrils. In Parkinson's disease (PD) and dementia with Lewy bodies, intraneuronal α-Syn aggregates are referred to as Lewy bodies in the somata and as Lewy neurites in the neuronal processes. In multiple system atrophy (MSA) α-Syn aggregates are also found within mature oligodendrocytes (OLs) where they form Glial Cytoplasmic Inclusions (GCIs). However, the origin of GCIs remains enigmatic: (i) mature OLs do not express α-Syn, precluding the seeding and the buildup of inclusions and (ii) the artificial overexpression of α-Syn in OLs of transgenic mice results in a burden of soluble phosphorylated α-Syn but fails to form α-Syn fibrils. In contrast, mass spectrometry of α-Syn fibrillar aggregates from MSA patients points to the neuronal origin of the proteins intimately associated with the fibrils within the GCIs. This suggests that GCIs are preassembled in neurons and only secondarily incorporated into OLs. Interestingly, we recently isolated a synthetic human α-Syn fibril strain (1B fibrils) capable of seeding a type of neuronal inclusion observed early and specifically during MSA. Our goal was thus to investigate whether the neuronal α-Syn pathology seeded by 1B fibrils could eventually be transmitted to OLs to form GCIs in vivo. After confirming that mature OLs did not express α-Syn to detectable levels in the adult mouse brain, a series of mice received unilateral intra-striatal injections of 1B fibrils. The resulting α-Syn pathology was visualized using phospho-S129 α-Syn immunoreactivity (pSyn). We found that even though 1B fibrils were injected unilaterally, many pSyn-positive neuronal somas were present in layer V of the contralateral perirhinal cortex after 6 weeks. This suggested a fast retrograde spread of the pathology along the axons of crossing cortico-striatal neurons. We thus scrutinized the posterior limb of the anterior commissure, i.e., the myelinated interhemispheric tract containing the axons of these neurons: we indeed observed numerous pSyn-positive linear Lewy Neurites oriented parallel to the commissural axis, corresponding to axonal segments filled with aggregated α-Syn, with no obvious signs of OL α-Syn pathology at this stage. After 6 months however, the commissural Lewy neurites were no longer parallel but fragmented, curled up, sometimes squeezed in-between two consecutive OLs in interfascicular strands, or even engulfed inside OL perikarya, thus forming GCIs. We conclude that the 1B fibril strain can rapidly induce an α-Syn pathology typical of MSA in mice, in which the appearance of GCIs results from the pruning of diseased axonal segments containing aggregated α-Syn.
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21
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Madden MB, Stewart BW, White MG, Krimmel SR, Qadir H, Barrett FS, Seminowicz DA, Mathur BN. A role for the claustrum in cognitive control. Trends Cogn Sci 2022; 26:1133-1152. [PMID: 36192309 PMCID: PMC9669149 DOI: 10.1016/j.tics.2022.09.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 09/02/2022] [Accepted: 09/07/2022] [Indexed: 01/12/2023]
Abstract
Early hypotheses of claustrum function were fueled by neuroanatomical data and yielded suggestions that the claustrum is involved in processes ranging from salience detection to multisensory integration for perceptual binding. While these hypotheses spurred useful investigations, incompatibilities inherent in these views must be reconciled to further conceptualize claustrum function amid a wealth of new data. Here, we review the varied models of claustrum function and synthesize them with developments in the field to produce a novel functional model: network instantiation in cognitive control (NICC). This model proposes that frontal cortices direct the claustrum to flexibly instantiate cortical networks to subserve cognitive control. We present literature support for this model and provide testable predictions arising from this conceptual framework.
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Affiliation(s)
- Maxwell B Madden
- Department of Pharmacology, School of Medicine, University of Maryland, Baltimore, MD 21201, USA
| | - Brent W Stewart
- Department of Pharmacology, School of Medicine, University of Maryland, Baltimore, MD 21201, USA; Department of Neural and Pain Sciences, School of Dentistry, University of Maryland, Baltimore, MD 21201, USA; Center to Advance Chronic Pain Research, University of Maryland, Baltimore, MD 21201, USA
| | - Michael G White
- Department of Pharmacology, School of Medicine, University of Maryland, Baltimore, MD 21201, USA
| | - Samuel R Krimmel
- Department of Neural and Pain Sciences, School of Dentistry, University of Maryland, Baltimore, MD 21201, USA; Center to Advance Chronic Pain Research, University of Maryland, Baltimore, MD 21201, USA
| | - Houman Qadir
- Department of Pharmacology, School of Medicine, University of Maryland, Baltimore, MD 21201, USA
| | - Frederick S Barrett
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA; Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD 21224, USA; Department of Psychological and Brain Sciences, Johns Hopkins University, Baltimore, MD 21224, USA
| | - David A Seminowicz
- Department of Neural and Pain Sciences, School of Dentistry, University of Maryland, Baltimore, MD 21201, USA; Center to Advance Chronic Pain Research, University of Maryland, Baltimore, MD 21201, USA; Department of Medical Biophysics, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Brian N Mathur
- Department of Pharmacology, School of Medicine, University of Maryland, Baltimore, MD 21201, USA; Department of Psychiatry, School of Medicine, University of Maryland, Baltimore, MD 21201, USA.
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22
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Morello T, Kollmar R, Stewart M, Orman R. The retrosplenial cortex of Carollia perspicillata, Seba's short-tailed fruit bat. Hippocampus 2022; 32:752-764. [PMID: 36018284 DOI: 10.1002/hipo.23464] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 08/01/2022] [Accepted: 08/08/2022] [Indexed: 11/11/2022]
Abstract
Retrosplenial cortex (RSC) is a brain region involved in critical cognitive functions including memory, planning, and spatial navigation and is commonly affected in neurodegenerative diseases. Subregions of RSC are typically described as Brodmann areas 29 and 30, which are defined by cytoarchitectural features. Using immunofluorescence, we studied the distributions of neurons immunoreactive for NeuN, latexin, and calcium binding proteins (calbindin, calretinin, and parvalbumin) in RSC of Carollia perspicillata, Seba's short-tailed fruit bat. We observed that latexin was specifically present in areas 29a and 29b but not 29c and 30. We further identified distribution patterns of calcium binding proteins that group areas 29a and 29b separately from areas 29c and 30. We conclude first that latexin is a useful marker to classify subregions of RSC and second that these subregions contain distinct patterns of neuronal immunoreactivity for calcium binding proteins. Given the long lifespan of Carollia, bat RSC may be a useful model in studying age-related neurodegeneration.
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Affiliation(s)
- Timothy Morello
- Department of Physiology & Pharmacology, SUNY Downstate Health Sciences University, Brooklyn, New York, USA
| | - Richard Kollmar
- Department of Cell Biology, SUNY Downstate Health Sciences University, Brooklyn, New York, USA.,Department of Otolaryngology, SUNY Downstate Health Sciences University, Brooklyn, New York, USA
| | - Mark Stewart
- Department of Physiology & Pharmacology, SUNY Downstate Health Sciences University, Brooklyn, New York, USA.,Department of Neurology, SUNY Downstate Health Sciences University, Brooklyn, New York, USA
| | - Rena Orman
- Department of Physiology & Pharmacology, SUNY Downstate Health Sciences University, Brooklyn, New York, USA
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Ravignani A, Lumaca M, Kotz SA. Interhemispheric Brain Communication and the Evolution of Turn-Taking in Mammals. Front Ecol Evol 2022. [DOI: 10.3389/fevo.2022.916956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
In the last 20 years, research on turn-taking and duetting has flourished in at least three, historically separate disciplines: animal behavior, language sciences, and music cognition. While different in scope and methods, all three ultimately share one goal—namely the understanding of timed interactions among conspecifics. In this perspective, we aim at connecting turn-taking and duetting across species from a neural perspective. While we are still far from a defined neuroethology of turn-taking, we argue that the human neuroscience of turn-taking and duetting can inform animal bioacoustics. For this, we focus on a particular concept, interhemispheric connectivity, and its main white-matter substrate, the corpus callosum. We provide an overview of the role of corpus callosum in human neuroscience and interactive music and speech. We hypothesize its mechanistic connection to turn-taking and duetting in our species, and a potential translational link to mammalian research. We conclude by illustrating empirical venues for neuroethological research of turn-taking and duetting in mammals.
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24
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Klein-Flügge MC, Bongioanni A, Rushworth MFS. Medial and orbital frontal cortex in decision-making and flexible behavior. Neuron 2022; 110:2743-2770. [PMID: 35705077 DOI: 10.1016/j.neuron.2022.05.022] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2022] [Revised: 05/17/2022] [Accepted: 05/19/2022] [Indexed: 11/15/2022]
Abstract
The medial frontal cortex and adjacent orbitofrontal cortex have been the focus of investigations of decision-making, behavioral flexibility, and social behavior. We review studies conducted in humans, macaques, and rodents and argue that several regions with different functional roles can be identified in the dorsal anterior cingulate cortex, perigenual anterior cingulate cortex, anterior medial frontal cortex, ventromedial prefrontal cortex, and medial and lateral parts of the orbitofrontal cortex. There is increasing evidence that the manner in which these areas represent the value of the environment and specific choices is different from subcortical brain regions and more complex than previously thought. Although activity in some regions reflects distributions of reward and opportunities across the environment, in other cases, activity reflects the structural relationships between features of the environment that animals can use to infer what decision to take even if they have not encountered identical opportunities in the past.
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Affiliation(s)
- Miriam C Klein-Flügge
- Wellcome Centre for Integrative Neuroimaging (WIN), Department of Experimental Psychology, University of Oxford, Tinsley Building, Mansfield Road, Oxford OX1 3TA, UK; Wellcome Centre for Integrative Neuroimaging (WIN), Centre for Functional MRI of the Brain (FMRIB), University of Oxford, Nuffield Department of Clinical Neurosciences, Level 6, West Wing, John Radcliffe Hospital, Oxford OX3 9DU, UK; Department of Psychiatry, University of Oxford, Warneford Lane, Headington, Oxford OX3 7JX, UK.
| | - Alessandro Bongioanni
- Wellcome Centre for Integrative Neuroimaging (WIN), Department of Experimental Psychology, University of Oxford, Tinsley Building, Mansfield Road, Oxford OX1 3TA, UK
| | - Matthew F S Rushworth
- Wellcome Centre for Integrative Neuroimaging (WIN), Department of Experimental Psychology, University of Oxford, Tinsley Building, Mansfield Road, Oxford OX1 3TA, UK; Wellcome Centre for Integrative Neuroimaging (WIN), Centre for Functional MRI of the Brain (FMRIB), University of Oxford, Nuffield Department of Clinical Neurosciences, Level 6, West Wing, John Radcliffe Hospital, Oxford OX3 9DU, UK
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25
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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: 20] [Impact Index Per Article: 10.0] [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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26
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Thittamranahalli Kariyappa J, Zanoni S, Bongers A, Tong L, Ashwell KWS. Magnetic resonance imaging and diffusion tensor imaging reconstruction of connectomes in a macropod, the quokka (Setonix brachyurus). J Comp Neurol 2022; 530:2188-2214. [PMID: 35417062 DOI: 10.1002/cne.25328] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 02/26/2022] [Accepted: 03/15/2022] [Indexed: 11/10/2022]
Abstract
The diversity of the diprotodontids provides an excellent opportunity to study how a basic marsupial cortical plan has been modified for the needs of the mammals living in different habitats. Very little is known about the connections of the cerebral cortex with the deep brain structures (basal ganglia and thalamus) in this evolutionarily significant group of mammals. In this study, we performed mapping of brain regions and connections in a diprotodontid marsupial from data obtained from an excised brain scanned in high-field (9.4 T) microstructural magnetic resonance imaging (MRI) instrument. The analysis was based on two MRI methodologies. First, high-resolution structural scans were used to map MRI visible brain regions from T1w and T2w images. Second, extensive diffusion tensor imaging (DTI) data were obtained to elucidate connectivity between brain areas using deterministic diffusion tracking of neuronal brain fibers. From the data, we were able to identify corticostriate connections between the frontal association and dorsomedial isocortex and the head of the caudate, and between the lateral somatosensory cortex and the putamen. We were also able to follow the olfactory and limbic connections by tracing fibers in the fornix, cingulum, intrabulbar part of the anterior commissure, and lateral olfactory tract. There was segregation of fibers in the anterior commissure such that olfactory connections passed through the rostroventral part and successively more dorsal cortical areas connected through more dorsal parts of the commissure. Our findings confirm a common pattern of cortical connectivity in therian mammals, even where brain expansion has occurred independently in diverse groups.
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Affiliation(s)
| | - Simone Zanoni
- Biological Resources and Imaging Laboratory, The University of New South Wales, Sydney, New South Wales, Australia
| | - Andre Bongers
- Biological Resources and Imaging Laboratory, The University of New South Wales, Sydney, New South Wales, Australia
| | - Lydia Tong
- Taronga Wildlife Hospital, Taronga Zoo, Taronga Conservation Society Australia, Sydney, New South Wales, Australia
| | - Ken W S Ashwell
- Department of Anatomy, School of Medical Sciences, The University of New South Wales, Sydney, New South Wales, Australia
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27
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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: 1.0] [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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Abstract
Structural brain anomalies are relatively common and may be detected either prenatally or postnatally. Brain malformations can be characterized based on the developmental processes that have been perturbed, either by environmental, infectious, disruptive or genetic causes. Fetuses and neonates with brain malformations should be thoroughly surveilled for potential other anomalies, and depending on the nature of the brain malformation, may require additional investigations such as genetic testing, ophthalmological examinations, cardiorespiratory monitoring, and screening laboratory studies.
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Innocenti GM, Schmidt K, Milleret C, Fabri M, Knyazeva MG, Battaglia-Mayer A, Aboitiz F, Ptito M, Caleo M, Marzi CA, Barakovic M, Lepore F, Caminiti R. The functional characterization of callosal connections. Prog Neurobiol 2021; 208:102186. [PMID: 34780864 PMCID: PMC8752969 DOI: 10.1016/j.pneurobio.2021.102186] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Revised: 11/05/2021] [Accepted: 11/11/2021] [Indexed: 12/12/2022]
Abstract
The functional characterization of callosal connections is informed by anatomical data. Callosal connections play a conditional driving role depending on the brain state and behavioral demands. Callosal connections play a modulatory function, in addition to a driving role. The corpus callosum participates in learning and interhemispheric transfer of sensorimotor habits. The corpus callosum contributes to language processing and cognitive functions.
The brain operates through the synaptic interaction of distant neurons within flexible, often heterogeneous, distributed systems. Histological studies have detailed the connections between distant neurons, but their functional characterization deserves further exploration. Studies performed on the corpus callosum in animals and humans are unique in that they capitalize on results obtained from several neuroscience disciplines. Such data inspire a new interpretation of the function of callosal connections and delineate a novel road map, thus paving the way toward a general theory of cortico-cortical connectivity. Here we suggest that callosal axons can drive their post-synaptic targets preferentially when coupled to other inputs endowing the cortical network with a high degree of conditionality. This might depend on several factors, such as their pattern of convergence-divergence, the excitatory and inhibitory operation mode, the range of conduction velocities, the variety of homotopic and heterotopic projections and, finally, the state-dependency of their firing. We propose that, in addition to direct stimulation of post-synaptic targets, callosal axons often play a conditional driving or modulatory role, which depends on task contingencies, as documented by several recent studies.
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Affiliation(s)
- Giorgio M Innocenti
- Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden; Signal Processing Laboratory (LTS5), École Polytechnique Fédérale (EPFL), Lausanne, Switzerland
| | - Kerstin Schmidt
- Brain Institute, Federal University of Rio Grande do Norte (UFRN), Natal, Brazil
| | - Chantal Milleret
- Center for Interdisciplinary Research in Biology, Collège de France, CNRS UMR 7241, INSERM U 1050, Label Memolife, PSL Research University, Paris, France
| | - Mara Fabri
- Department of Life and Environmental Sciences, Marche Polytechnic University, Ancona, Italy
| | - Maria G Knyazeva
- Laboratoire de Recherche en Neuroimagerie (LREN), Department of Clinical Neurosciences, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland; Leenaards Memory Centre and Department of Clinical Neurosciences, Centre Hospitalier Universitaire Vaudois and University of Lausanne, Lausanne, Switzerland
| | | | - Francisco Aboitiz
- Centro Interdisciplinario de Neurociencias and Departamento de Psiquiatría, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Maurice Ptito
- Harland Sanders Chair in Visual Science, École d'Optométrie, Université de Montréal, Montréal, Qc, Canada; Department of Neurology and Neurosurgery, Montréal Neurological Institute, McGill University, Montréal, Qc, Canada; Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark
| | - Matteo Caleo
- Department of Biomedical Sciences, University of Padua, Italy; CNR Neuroscience Institute, Pisa, Italy
| | - Carlo A Marzi
- Department of Neuroscience, Biomedicine and Movement, University of Verona, Verona, Italy
| | - Muhamed Barakovic
- Signal Processing Laboratory (LTS5), École Polytechnique Fédérale (EPFL), Lausanne, Switzerland
| | - Franco Lepore
- Department of Psychology, Centre de Recherche en Neuropsychologie et Cognition, University of Montréal, Montréal, QC, Canada
| | - Roberto Caminiti
- Department of Physiology and Pharmacology, University of Rome SAPIENZA, Rome, Italy; Neuroscience and Behavior Laboratory, Istituto Italiano di Tecnologia, Rome, Italy.
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30
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A Fiber Dissection Study of the Anterior Commissure: Correlations with Diffusion Spectrum Imaging Tractography and Clinical Relevance in Gliomas. Brain Topogr 2021; 35:232-240. [PMID: 34755238 DOI: 10.1007/s10548-021-00879-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Accepted: 10/29/2021] [Indexed: 11/27/2022]
Abstract
The anterior commissure, which connects bilateral temporal lobes and olfactive areas, remains elusive in many aspects of its structure and functional role. To comparatively describe anatomical details of the anterior commissure using cadaveric fiber dissection (FD) and diffusion spectrum imaging (DSI) thus refining our knowledge of the tract and exploring its clinical relevance in glioma migration. Twelve normal postmortem hemispheres were treated with Klingler's method and subjected to FD with medial, inferior, and lateral approaches. The FD findings were correlated with DSI tractography results. To illustrate the clinical relevance, two patients with recurrent temporal high-grade glioma are described. Our FD and DSI tractography of the anterior commissure disclosed a new anatomical paradigm. The FD confirmed that the anterior limb (absent sometimes and variable) and the lateral/temporal extension include the rostral portion and caudal portion, respectively, of the anterior commissure fibers. The shape of the lateral/temporal extension predominantly resembles an 'H'. The DSI tractography findings corresponded to these FD results. According to the FD, the Virchow-Robin space is continuous with the subarachnoid space and very close to the anterior commissure. The two clinical cases presented severe disturbances of consciousness and behavior despite good local tumor control. Subsequent magnetic resonance images showed new lesions infiltrating the contralateral temporal lobes. FD combined with DSI provided anatomical details facilitating a better understanding of the anterior commissure. Glioma migration routes to the contralateral temporal lobe included the anterior commissure, Virchow-Robin space, and subarachnoid space and were clinically relevant.
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31
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Szczupak D, Iack PM, Liu C, Tovar-Moll F, Lent R, Silva AC. Direct Interhemispheric Cortical Communication via Thalamic Commissures: A New White-Matter Pathway in the Rodent Brain. Cereb Cortex 2021; 31:4642-4651. [PMID: 33999140 PMCID: PMC8408456 DOI: 10.1093/cercor/bhab112] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 03/16/2021] [Accepted: 04/07/2021] [Indexed: 11/14/2022] Open
Abstract
The corpus callosum (CC), the anterior (AC), and the posterior (PC) commissures are the principal axonal fiber bundle pathways that allow bidirectional communication between the brain hemispheres. Here, we used the Allen mouse brain connectivity atlas and high-resolution diffusion-weighted MRI (DWI) to investigate interhemispheric fiber bundles in C57bl6/J mice, the most commonly used wild-type mouse model in biomedical research. We identified 1) commissural projections from the primary motor area through the AC to the contralateral hemisphere; and 2) intrathalamic interhemispheric fiber bundles from multiple regions in the frontal cortex to the contralateral thalamus. This is the first description of direct interhemispheric corticothalamic connectivity from the orbital cortex. We named these newly identified crossing points thalamic commissures. We also analyzed interhemispheric connectivity in the Balb/c mouse model of dysgenesis of the corpus callosum (CCD). Relative to C57bl6/J, Balb/c presented an atypical and smaller AC and weaker interhemispheric corticothalamic communication. These results redefine our understanding of interhemispheric brain communication. Specifically, they establish the thalamus as a regular hub for interhemispheric connectivity and encourage us to reinterpret brain plasticity in CCD as an altered balance between axonal reinforcement and pruning.
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Affiliation(s)
- Diego Szczupak
- Department of Neurobiology, University of Pittsburgh Brain Institute, University of Pittsburgh, Pittsburgh, PA 15261, USA
- Cerebral Microcirculation Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
| | - Pamela Meneses Iack
- Biomedical Sciences Institute, Federal University of Rio de Janeiro, Rio de Janeiro 21941-590, Brazil
| | - Cirong Liu
- Department of Neurobiology, University of Pittsburgh Brain Institute, University of Pittsburgh, Pittsburgh, PA 15261, USA
- Cerebral Microcirculation Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
- Institute of Neuroscience, CAS Center for Excellence in Brain Science and Intelligence Technology, Chinese Academy of Sciences, Shanghai 200031, China
| | - IRC5 Consortium
- Researchers of the International Research Consortium for the Corpus Callosum and Cerebral Connectivity (IRC5), Pasadena, CA 91125, USA
| | | | - Roberto Lent
- Biomedical Sciences Institute, Federal University of Rio de Janeiro, Rio de Janeiro 21941-590, Brazil
- D’Or Institute of Research and Education, Rio de Janeiro 22281-100, Brazil
| | - Afonso C Silva
- Department of Neurobiology, University of Pittsburgh Brain Institute, University of Pittsburgh, Pittsburgh, PA 15261, USA
- Cerebral Microcirculation Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
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32
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Rogers LJ. Brain Lateralization and Cognitive Capacity. Animals (Basel) 2021; 11:1996. [PMID: 34359124 PMCID: PMC8300231 DOI: 10.3390/ani11071996] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 06/26/2021] [Accepted: 06/30/2021] [Indexed: 12/29/2022] Open
Abstract
One way to increase cognitive capacity is to avoid duplication of functions on the left and right sides of the brain. There is a convincing body of evidence showing that such asymmetry, or lateralization, occurs in a wide range of both vertebrate and invertebrate species. Each hemisphere of the brain can attend to different types of stimuli or to different aspects of the same stimulus and each hemisphere analyses information using different neural processes. A brain can engage in more than one task at the same time, as in monitoring for predators (right hemisphere) while searching for food (left hemisphere). Increased cognitive capacity is achieved if individuals are lateralized in one direction or the other. The advantages and disadvantages of individual lateralization are discussed. This paper argues that directional, or population-level, lateralization, which occurs when most individuals in a species have the same direction of lateralization, provides no additional increase in cognitive capacity compared to individual lateralization although directional lateralization is advantageous in social interactions. Strength of lateralization is considered, including the disadvantage of being very strongly lateralized. The role of brain commissures is also discussed with consideration of cognitive capacity.
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Affiliation(s)
- Lesley J Rogers
- School of Science and Technology, University of New England, Armidale, NSW 2351, Australia
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33
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Fenlon LR, Suarez R, Lynton Z, Richards LJ. The evolution, formation and connectivity of the anterior commissure. Semin Cell Dev Biol 2021; 118:50-59. [PMID: 33958283 DOI: 10.1016/j.semcdb.2021.04.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 04/08/2021] [Accepted: 04/10/2021] [Indexed: 10/21/2022]
Abstract
The anterior commissure is the most ancient of the forebrain interhemispheric connections among all vertebrates. Indeed, it is the predominant pallial commissure in all non-eutherian vertebrates, universally subserving basic functions related to olfaction and survival. A key feature of the anterior commissure is its ability to convey connections from diverse brain areas, such as most of the neocortex in non-eutherian mammals, thereby mediating the bilateral integration of diverse functions. Shared developmental mechanisms between the anterior commissure and more evolutionarily recent commissures, such as the corpus callosum in eutherians, have led to the hypothesis that the former may have been a precursor for additional expansion of commissural circuits. However, differences between the formation of the anterior commissure and other telencephalic commissures suggest that independent developmental mechanisms underlie the emergence of these connections in extant species. Here, we review the developmental mechanisms and connectivity of the anterior commissure across evolutionarily distant species, and highlight its potential functional importance in humans, both in the course of normal neurodevelopment, and as a site of plastic axonal rerouting in the absence or damage of other connections.
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Affiliation(s)
- Laura R Fenlon
- The University of Queensland, The Queensland Brain Institute, Brisbane, Australia.
| | - Rodrigo Suarez
- The University of Queensland, The Queensland Brain Institute, Brisbane, Australia
| | - Zorana Lynton
- The University of Queensland, The Queensland Brain Institute, Brisbane, Australia; The Faculty of Medicine, Brisbane, Australia
| | - Linda J Richards
- The University of Queensland, The Queensland Brain Institute, Brisbane, Australia; The School of Biomedical Sciences, Brisbane, Australia.
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34
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Morcom L, Gobius I, Marsh APL, Suárez R, Lim JWC, Bridges C, Ye Y, Fenlon LR, Zagar Y, Douglass AM, Donahoo ALS, Fothergill T, Shaikh S, Kozulin P, Edwards TJ, Cooper HM, Sherr EH, Chédotal A, Leventer RJ, Lockhart PJ, Richards LJ. DCC regulates astroglial development essential for telencephalic morphogenesis and corpus callosum formation. eLife 2021; 10:e61769. [PMID: 33871356 PMCID: PMC8116049 DOI: 10.7554/elife.61769] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 04/18/2021] [Indexed: 02/04/2023] Open
Abstract
The forebrain hemispheres are predominantly separated during embryogenesis by the interhemispheric fissure (IHF). Radial astroglia remodel the IHF to form a continuous substrate between the hemispheres for midline crossing of the corpus callosum (CC) and hippocampal commissure (HC). Deleted in colorectal carcinoma (DCC) and netrin 1 (NTN1) are molecules that have an evolutionarily conserved function in commissural axon guidance. The CC and HC are absent in Dcc and Ntn1 knockout mice, while other commissures are only partially affected, suggesting an additional aetiology in forebrain commissure formation. Here, we find that these molecules play a critical role in regulating astroglial development and IHF remodelling during CC and HC formation. Human subjects with DCC mutations display disrupted IHF remodelling associated with CC and HC malformations. Thus, axon guidance molecules such as DCC and NTN1 first regulate the formation of a midline substrate for dorsal commissures prior to their role in regulating axonal growth and guidance across it.
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Affiliation(s)
- Laura Morcom
- The University of Queensland, Queensland Brain InstituteBrisbaneAustralia
| | - Ilan Gobius
- The University of Queensland, Queensland Brain InstituteBrisbaneAustralia
| | - Ashley PL Marsh
- Bruce Lefroy Centre for Genetic Health Research, Murdoch Children’s Research Institute, Royal Children’s HospitalParkvilleAustralia
- Department of Paediatrics, University of MelbourneParkvilleAustralia
| | - Rodrigo Suárez
- The University of Queensland, Queensland Brain InstituteBrisbaneAustralia
| | - Jonathan WC Lim
- The University of Queensland, Queensland Brain InstituteBrisbaneAustralia
| | - Caitlin Bridges
- The University of Queensland, Queensland Brain InstituteBrisbaneAustralia
| | - Yunan Ye
- The University of Queensland, Queensland Brain InstituteBrisbaneAustralia
| | - Laura R Fenlon
- The University of Queensland, Queensland Brain InstituteBrisbaneAustralia
| | - Yvrick Zagar
- Sorbonne Université, INSERM, CNRS, Institut de la VisionParisFrance
| | - Amelia M Douglass
- The University of Queensland, Queensland Brain InstituteBrisbaneAustralia
| | | | - Thomas Fothergill
- The University of Queensland, Queensland Brain InstituteBrisbaneAustralia
| | - Samreen Shaikh
- The University of Queensland, Queensland Brain InstituteBrisbaneAustralia
| | - Peter Kozulin
- The University of Queensland, Queensland Brain InstituteBrisbaneAustralia
| | - Timothy J Edwards
- The University of Queensland, Queensland Brain InstituteBrisbaneAustralia
- The University of Queensland, Faculty of MedicineBrisbaneAustralia
| | - Helen M Cooper
- The University of Queensland, Queensland Brain InstituteBrisbaneAustralia
| | - IRC5 Consortium
- Members and Affiliates of the International Research Consortium for the Corpus Callosum and Cerebral Connectivity (IRC5)Los AngelesUnited States
| | - Elliott H Sherr
- Departments of Neurology and Pediatrics, Institute of Human Genetics and Weill Institute of Neurosciences, University of California, San FranciscoSan FranciscoUnited States
| | - Alain Chédotal
- Sorbonne Université, INSERM, CNRS, Institut de la VisionParisFrance
| | - Richard J Leventer
- Department of Paediatrics, University of MelbourneParkvilleAustralia
- Neuroscience Research Group, Murdoch Children’s Research InstituteParkvilleAustralia
- Department of Neurology, University of Melbourne, Royal Children’s HospitalParkvilleAustralia
| | - Paul J Lockhart
- Bruce Lefroy Centre for Genetic Health Research, Murdoch Children’s Research Institute, Royal Children’s HospitalParkvilleAustralia
- Department of Paediatrics, University of MelbourneParkvilleAustralia
| | - Linda J Richards
- The University of Queensland, Queensland Brain InstituteBrisbaneAustralia
- The University of Queensland, School of Biomedical SciencesBrisbaneAustralia
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35
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Todorov OS, Blomberg SP, Goswami A, Sears K, Drhlík P, Peters J, Weisbecker V. Testing hypotheses of marsupial brain size variation using phylogenetic multiple imputations and a Bayesian comparative framework. Proc Biol Sci 2021; 288:20210394. [PMID: 33784860 PMCID: PMC8059968 DOI: 10.1098/rspb.2021.0394] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 03/01/2021] [Indexed: 12/20/2022] Open
Abstract
Considerable controversy exists about which hypotheses and variables best explain mammalian brain size variation. We use a new, high-coverage dataset of marsupial brain and body sizes, and the first phylogenetically imputed full datasets of 16 predictor variables, to model the prevalent hypotheses explaining brain size evolution using phylogenetically corrected Bayesian generalized linear mixed-effects modelling. Despite this comprehensive analysis, litter size emerges as the only significant predictor. Marsupials differ from the more frequently studied placentals in displaying a much lower diversity of reproductive traits, which are known to interact extensively with many behavioural and ecological predictors of brain size. Our results therefore suggest that studies of relative brain size evolution in placental mammals may require targeted co-analysis or adjustment of reproductive parameters like litter size, weaning age or gestation length. This supports suggestions that significant associations between behavioural or ecological variables with relative brain size may be due to a confounding influence of the extensive reproductive diversity of placental mammals.
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Affiliation(s)
- Orlin S. Todorov
- School of Biological Sciences, The University of Queensland, St Lucia, Queensland, Australia
| | - Simone P. Blomberg
- School of Biological Sciences, The University of Queensland, St Lucia, Queensland, Australia
| | - Anjali Goswami
- Genetics, Evolution, and Environment Department, University College London, UK
- Department of Life Sciences, Natural History Museum, London, UK
| | - Karen Sears
- Department of Ecology and Evolutionary Biology, College of Life Sciences, University of California Los Angeles, CA, USA
| | - Patrik Drhlík
- Faculty of Mechatronics, Informatics and Interdisciplinary Studies, Technical University of Liberec, Czechia
| | - James Peters
- Department of Animal Biology, University of Illinois at Urbana Champaign, USA
| | - Vera Weisbecker
- School of Biological Sciences, The University of Queensland, St Lucia, Queensland, Australia
- College of Science and Engineering, Flinders University, Australia
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36
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Bruguier H, Suarez R, Manger P, Hoerder-Suabedissen A, Shelton AM, Oliver DK, Packer AM, Ferran JL, García-Moreno F, Puelles L, Molnár Z. In search of common developmental and evolutionary origin of the claustrum and subplate. J Comp Neurol 2020; 528:2956-2977. [PMID: 32266722 DOI: 10.1002/cne.24922] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 04/01/2020] [Accepted: 04/02/2020] [Indexed: 02/06/2023]
Abstract
The human claustrum, a major hub of widespread neocortical connections, is a thin, bilateral sheet of gray matter located between the insular cortex and the striatum. The subplate is a largely transient cortical structure that contains some of the earliest generated neurons of the cerebral cortex and has important developmental functions to establish intra- and extracortical connections. In human and macaque some subplate cells undergo regulated cell death, but some remain as interstitial white matter cells. In mouse and rat brains a compact layer is formed, Layer 6b, and it remains underneath the cortex, adjacent to the white matter. Whether Layer 6b in rodents is homologous to primate subplate or interstitial white matter cells is still debated. Gene expression patterns, such as those of Nurr1/Nr4a2, have suggested that the rodent subplate and the persistent subplate cells in Layer 6b and the claustrum might have similar origins. Moreover, the birthdates of the claustrum and Layer 6b are similarly precocious in mice. These observations prompted our speculations on the common developmental and evolutionary origin of the claustrum and the subplate. Here we systematically compare the currently available data on cytoarchitecture, evolutionary origin, gene expression, cell types, birthdates, neurogenesis, lineage and migration, circuit connectivity, and cell death of the neurons that contribute to the claustrum and subplate. Based on their similarities and differences we propose a partially common early evolutionary origin of the cells that become claustrum and subplate, a likely scenario that is shared in these cell populations across all amniotes.
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Affiliation(s)
- Hannah Bruguier
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Rodrigo Suarez
- Queensland Brain Institute, The University of Queensland, Brisbane, Queensland, Australia
| | - Paul Manger
- School of Anatomical Sciences, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
| | | | - Andrew M Shelton
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - David K Oliver
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Adam M Packer
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - José L Ferran
- Department of Human Anatomy, Medical School, University of Murcia and Murcia Arrixaca Institute for Biomedical Research, Murcia, Spain
| | - Fernando García-Moreno
- Achucarro Basque Center for Neuroscience, Zamudio, Spain.,IKERBASQUE Foundation, Bilbao, Spain
| | - Luis Puelles
- Department of Human Anatomy, Medical School, University of Murcia and Murcia Arrixaca Institute for Biomedical Research, Murcia, Spain
| | - Zoltán Molnár
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
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37
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Vianna-Barbosa R, Bahia CP, Sanabio A, de Freitas GPA, Madeiro da Costa RF, Garcez PP, Miranda K, Lent R, Tovar-Moll F. Myelination of Callosal Axons Is Hampered by Early and Late Forelimb Amputation in Rats. Cereb Cortex Commun 2020; 2:tgaa090. [PMID: 34296146 PMCID: PMC8152840 DOI: 10.1093/texcom/tgaa090] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 11/17/2020] [Accepted: 11/22/2020] [Indexed: 11/14/2022] Open
Abstract
Deafferentation is an important determinant of plastic changes in the CNS, which consists of a loss of inputs from the body periphery or from the CNS itself. Although cortical reorganization has been well documented, white matter plasticity was less explored. Our goal was to investigate microstructural interhemispheric connectivity changes in early and late amputated rats. For that purpose, we employed diffusion-weighted magnetic resonance imaging, as well as Western blotting, immunohistochemistry, and electron microscopy of sections of the white matter tracts to analyze the microstructural changes in the corticospinal tract and in the corpus callosum (CC) sector that contains somatosensory fibers integrating cortical areas representing the forelimbs and compare differences in rats undergoing forelimb amputation as neonates, with those amputated as adults. Results showed that early amputation induced decreased fractional anisotropy values and reduction of total myelin amount in the cerebral peduncle contralateral to the amputation. Both early and late forelimb amputations induced decreased myelination of callosal fibers. While early amputation affected myelination of thinner axons, late amputation disrupted axons of all calibers. Since the CC provides a modulation of inhibition and excitation between the hemispheres, we suggest that the demyelination observed among callosal fibers may misbalance this modulation.
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Affiliation(s)
- Rodrigo Vianna-Barbosa
- Post-Graduate Program in Morphological Sciences, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro CEP 21941-902, Brazil.,National Center of Structural Biology and Bioimaging, Federal University of Rio de Janeiro, Rio de Janeiro CEP 21941-902, Brazil
| | - Carlomagno P Bahia
- Institute of Health Sciences, Federal University of Pará, Pará CEP 66035-160, Brazil
| | - Alexandre Sanabio
- Post-Graduate Program in Morphological Sciences, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro CEP 21941-902, Brazil
| | - Gabriella P A de Freitas
- Post-Graduate Program in Morphological Sciences, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro CEP 21941-902, Brazil
| | | | - Patricia P Garcez
- Post-Graduate Program in Morphological Sciences, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro CEP 21941-902, Brazil
| | - Kildare Miranda
- National Center of Structural Biology and Bioimaging, Federal University of Rio de Janeiro, Rio de Janeiro CEP 21941-902, Brazil.,Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro CEP 21941-902, Brazil
| | - Roberto Lent
- Post-Graduate Program in Morphological Sciences, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro CEP 21941-902, Brazil.,D'Or Institute of Research and Education (IDOR), Rio de Janeiro, CEP 22281-100, Brazil
| | - Fernanda Tovar-Moll
- Post-Graduate Program in Morphological Sciences, Institute of Biomedical Sciences, Federal University of Rio de Janeiro, Rio de Janeiro CEP 21941-902, Brazil.,National Center of Structural Biology and Bioimaging, Federal University of Rio de Janeiro, Rio de Janeiro CEP 21941-902, Brazil.,D'Or Institute of Research and Education (IDOR), Rio de Janeiro, CEP 22281-100, Brazil
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38
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An evolutionarily acquired microRNA shapes development of mammalian cortical projections. Proc Natl Acad Sci U S A 2020; 117:29113-29122. [PMID: 33139574 PMCID: PMC7682328 DOI: 10.1073/pnas.2006700117] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The mammalian central nervous system contains unique projections from the cerebral cortex thought to underpin complex motor and cognitive skills, including the corticospinal tract and corpus callosum. The neurons giving rise to these projections—corticospinal and callosal projection neurons—develop from the same progenitors, but acquire strikingly different fates. The broad evolutionary conservation of known genes controlling cortical projection neuron fates raises the question of how the more narrowly conserved corticospinal and callosal projections evolved. We identify a microRNA cluster selectively expressed by corticospinal projection neurons and exclusive to placental mammals. One of these microRNAs promotes corticospinal fate via regulation of the callosal gene LMO4, suggesting a mechanism whereby microRNA regulation during development promotes evolution of neuronal diversity. The corticospinal tract is unique to mammals and the corpus callosum is unique to placental mammals (eutherians). The emergence of these structures is thought to underpin the evolutionary acquisition of complex motor and cognitive skills. Corticospinal motor neurons (CSMN) and callosal projection neurons (CPN) are the archetypal projection neurons of the corticospinal tract and corpus callosum, respectively. Although a number of conserved transcriptional regulators of CSMN and CPN development have been identified in vertebrates, none are unique to mammals and most are coexpressed across multiple projection neuron subtypes. Here, we discover 17 CSMN-enriched microRNAs (miRNAs), 15 of which map to a single genomic cluster that is exclusive to eutherians. One of these, miR-409-3p, promotes CSMN subtype identity in part via repression of LMO4, a key transcriptional regulator of CPN development. In vivo, miR-409-3p is sufficient to convert deep-layer CPN into CSMN. This is a demonstration of an evolutionarily acquired miRNA in eutherians that refines cortical projection neuron subtype development. Our findings implicate miRNAs in the eutherians’ increase in neuronal subtype and projection diversity, the anatomic underpinnings of their complex behavior.
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39
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Abstract
The claustrum is one of the most widely connected regions of the forebrain, yet its function has remained obscure, largely due to the experimentally challenging nature of targeting this small, thin, and elongated brain area. However, recent advances in molecular techniques have enabled the anatomy and physiology of the claustrum to be studied with the spatiotemporal and cell type–specific precision required to eventually converge on what this area does. Here we review early anatomical and electrophysiological results from cats and primates, as well as recent work in the rodent, identifying the connectivity, cell types, and physiological circuit mechanisms underlying the communication between the claustrum and the cortex. The emerging picture is one in which the rodent claustrum is closely tied to frontal/limbic regions and plays a role in processes, such as attention, that are associated with these areas.
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Affiliation(s)
- Jesse Jackson
- Department of Physiology and Neuroscience and Mental Health Institute, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
| | - Jared B. Smith
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, California 92037, USA
| | - Albert K. Lee
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, Virginia 20147, USA
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40
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Assaf Y, Bouznach A, Zomet O, Marom A, Yovel Y. Conservation of brain connectivity and wiring across the mammalian class. Nat Neurosci 2020; 23:805-808. [PMID: 32514137 DOI: 10.1038/s41593-020-0641-7] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 04/10/2020] [Indexed: 11/09/2022]
Abstract
Over 100 years ago, Ramon y Cajal hypothesized that two forces played a role in the evolution of mammalian brain connectivity: minimizing wiring costs and maximizing conductivity speed. Using diffusion MRI, we reconstructed the brain connectomes of 123 mammalian species. Network analysis revealed that both connectivity and the wiring cost are conserved across mammals. We describe a conservation principle that maintains the overall connectivity: species with fewer interhemispheric connections exhibit better intrahemispheric connectivity.
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Affiliation(s)
- Yaniv Assaf
- School of Neurobiology, Biochemistry and Biophysics, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel. .,Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel.
| | | | - Omri Zomet
- School of Computer Sciences, Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Assaf Marom
- Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel
| | - Yossi Yovel
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, Israel. .,School of Zoology, The George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel. .,The Steinhardt Museum of Natural History, National Research Center for Biodiversity Studies, Tel-Aviv University, Tel Aviv, Israel.
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41
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Paolino A, Fenlon LR, Kozulin P, Haines E, Lim JWC, Richards LJ, Suárez R. Differential timing of a conserved transcriptional network underlies divergent cortical projection routes across mammalian brain evolution. Proc Natl Acad Sci U S A 2020; 117:10554-10564. [PMID: 32312821 PMCID: PMC7229759 DOI: 10.1073/pnas.1922422117] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A unique combination of transcription factor expression and projection neuron identity demarcates each layer of the cerebral cortex. During mouse and human cortical development, the transcription factor CTIP2 specifies neurons that project subcerebrally, while SATB2 specifies neuronal projections via the corpus callosum, a large axon tract connecting the two neocortical hemispheres that emerged exclusively in eutherian mammals. Marsupials comprise the sister taxon of eutherians but do not have a corpus callosum; their intercortical commissural neurons instead project via the anterior commissure, similar to egg-laying monotreme mammals. It remains unknown whether divergent transcriptional networks underlie these cortical wiring differences. Here, we combine birth-dating analysis, retrograde tracing, gene overexpression and knockdown, and axonal quantification to compare the functions of CTIP2 and SATB2 in neocortical development, between the eutherian mouse and the marsupial fat-tailed dunnart. We demonstrate a striking degree of structural and functional homology, whereby CTIP2 or SATB2 of either species is sufficient to promote a subcerebral or commissural fate, respectively. Remarkably, we reveal a substantial delay in the onset of developmental SATB2 expression in mice as compared to the equivalent stage in dunnarts, with premature SATB2 overexpression in mice to match that of dunnarts resulting in a marsupial-like projection fate via the anterior commissure. Our results suggest that small alterations in the timing of regulatory gene expression may underlie interspecies differences in neuronal projection fate specification.
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Affiliation(s)
- Annalisa Paolino
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Laura R Fenlon
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia;
| | - Peter Kozulin
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Elizabeth Haines
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Jonathan W C Lim
- 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, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Rodrigo Suárez
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia;
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42
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Kermen F, Lal P, Faturos NG, Yaksi E. Interhemispheric connections between olfactory bulbs improve odor detection. PLoS Biol 2020; 18:e3000701. [PMID: 32310946 PMCID: PMC7192517 DOI: 10.1371/journal.pbio.3000701] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 04/30/2020] [Accepted: 04/02/2020] [Indexed: 01/06/2023] Open
Abstract
Interhemispheric connections enable interaction and integration of sensory information in bilaterian nervous systems and are thought to optimize sensory computations. However, the cellular and spatial organization of interhemispheric networks and the computational properties they mediate in vertebrates are still poorly understood. Thus, it remains unclear to what extent the connectivity between left and right brain hemispheres participates in sensory processing. Here, we show that the zebrafish olfactory bulbs (OBs) receive direct interhemispheric projections from their contralateral counterparts in addition to top-down inputs from the contralateral zebrafish homolog of olfactory cortex. The direct interhemispheric projections between the OBs reach peripheral layers of the contralateral OB and retain a precise topographic organization, which directly connects similarly tuned olfactory glomeruli across hemispheres. In contrast, interhemispheric top-down inputs consist of diffuse projections that broadly innervate the inhibitory granule cell layer. Jointly, these interhemispheric connections elicit a balance of topographically organized excitation and nontopographic inhibition on the contralateral OB and modulate odor responses. We show that the interhemispheric connections in the olfactory system enable the modulation of odor response and contribute to a small but significant improvement in the detection of a reproductive pheromone when presented together with complex olfactory cues by potentiating the response of the pheromone selective neurons. Taken together, our data show a previously unknown function for an interhemispheric connection between chemosensory maps of the olfactory system. Interhemispheric connections enable interaction and integration of sensory information in bilaterian nervous systems and are thought to optimize sensory computations. This study shows that interhemispheric olfactory connections in the zebrafish brain improve the detection of a reproductive pheromone within a noisy odor background.
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Affiliation(s)
- Florence Kermen
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
- Neuro-Electronics Research Flanders, Leuven, Belgium
- Department of Biology, Faculty of Natural Sciences, Norwegian University of Science and Technology, Trondheim, Norway
- * E-mail: (FK); (EY)
| | - Pradeep Lal
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
| | - Nicholas G. Faturos
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
| | - Emre Yaksi
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway
- Neuro-Electronics Research Flanders, Leuven, Belgium
- * E-mail: (FK); (EY)
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43
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Behrmann M, Plaut DC. Hemispheric Organization for Visual Object Recognition: A Theoretical Account and Empirical Evidence. Perception 2020; 49:373-404. [PMID: 31980013 PMCID: PMC9944149 DOI: 10.1177/0301006619899049] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Despite the similarity in structure, the hemispheres of the human brain have somewhat different functions. A traditional view of hemispheric organization asserts that there are independent and largely lateralized domain-specific regions in ventral occipitotemporal (VOTC), specialized for the recognition of distinct classes of objects. Here, we offer an alternative account of the organization of the hemispheres, with a specific focus on face and word recognition. This alternative account relies on three computational principles: distributed representations and knowledge, cooperation and competition between representations, and topography and proximity. The crux is that visual recognition results from a network of regions with graded functional specialization that is distributed across both hemispheres. Specifically, the claim is that face recognition, which is acquired relatively early in life, is processed by VOTC regions in both hemispheres. Once literacy is acquired, word recognition, which is co-lateralized with language areas, primarily engages the left VOTC and, consequently, face recognition is primarily, albeit not exclusively, mediated by the right VOTC. We review psychological and neural evidence from a range of studies conducted with normal and brain-damaged adults and children and consider findings which challenge this account. Last, we offer suggestions for future investigations whose findings may further refine this account.
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Affiliation(s)
- Marlene Behrmann
- Department of Psychology and Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA, USA
| | - David C. Plaut
- Department of Psychology and Neuroscience Institute, Carnegie Mellon University, Pittsburgh, PA, USA
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44
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Chung WS, Kurniawan ND, Marshall NJ. Toward an MRI-Based Mesoscale Connectome of the Squid Brain. iScience 2020; 23:100816. [PMID: 31972515 PMCID: PMC6974791 DOI: 10.1016/j.isci.2019.100816] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 12/11/2019] [Accepted: 12/27/2019] [Indexed: 01/05/2023] Open
Abstract
Using high-resolution diffusion magnetic resonance imaging (dMRI) and a suite of old and new staining techniques, the beginnings of a multi-scale connectome map of the squid brain is erected. The first of its kind for a cephalopod, this includes the confirmation of 281 known connections with the addition of 145 previously undescribed pathways. These and other features suggest a suite of functional attributes, including (1) retinotopic organization through the optic lobes and into other brain areas well beyond that previously recognized, (2) a level of complexity and sub-division in the basal lobe supporting ideas of convergence with the vertebrate basal ganglia, and (3) differential lobe-dependent growth rates that mirror complexity and transitions in ontogeny.
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Affiliation(s)
- Wen-Sung Chung
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD 4072, Australia.
| | - Nyoman D Kurniawan
- Centre for Advanced Imaging, The University of Queensland, St Lucia, QLD 4072, Australia
| | - N Justin Marshall
- Queensland Brain Institute, The University of Queensland, St Lucia, QLD 4072, Australia.
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45
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Abstract
The dramatic evolutionary expansion of the neocortex, together with a proliferation of specialized cortical areas, is believed to underlie the emergence of human cognitive abilities. In a broader phylogenetic context, however, neocortex evolution in mammals, including humans, is remarkably conservative, characterized largely by size variations on a shared six-layered neuronal architecture. By contrast, the telencephalon in non-mammalian vertebrates, including reptiles, amphibians, bony and cartilaginous fishes, and cyclostomes, features a great variety of very different tissue structures. Our understanding of the evolutionary relationships of these telencephalic structures, especially those of basally branching vertebrates and invertebrate chordates, remains fragmentary and is impeded by conceptual obstacles. To make sense of highly divergent anatomies requires a hierarchical view of biological organization, one that permits the recognition of homologies at multiple levels beyond neuroanatomical structure. Here we review the origin and diversification of the telencephalon with a focus on key evolutionary innovations shaping the neocortex at multiple levels of organization.
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Affiliation(s)
- Steven D Briscoe
- Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany.
| | - Clifton W Ragsdale
- Department of Neurobiology, University of Chicago, Chicago, IL 60637, USA; Department of Organismal Biology and Anatomy, University of Chicago, Chicago, IL 60637, USA
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46
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Miller DJ, Bhaduri A, Sestan N, Kriegstein A. Shared and derived features of cellular diversity in the human cerebral cortex. Curr Opin Neurobiol 2019; 56:117-124. [PMID: 30677551 PMCID: PMC6996583 DOI: 10.1016/j.conb.2018.12.005] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 12/11/2018] [Accepted: 12/15/2018] [Indexed: 12/11/2022]
Abstract
The cerebral cortex is the hallmark of the mammalian nervous system, and its large size and cellular diversity in humans support our most sophisticated cognitive abilities. Although the basic cellular organization of the cortex is conserved across mammals, cells have diversified during evolution. An increasingly integrated taxonomy of cell types, especially with the advent of single-cell transcriptomic data, has revealed an unprecedented variety of human cortical cell subtypes. Here, we broadly review the cellular composition and diversity of the mammalian brain, and how progenitor pools generate cell subtypes during development. We then discuss human cortical cells that are distinct from rodent cells, as well as the challenges and advantages of using model systems to study human cell types in health and disease.
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Affiliation(s)
- Daniel J Miller
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT, USA
| | - Aparna Bhaduri
- Department of Neurology and the Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research at the University of California, San Francisco, San Francisco, CA, USA
| | - Nenad Sestan
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT, USA; Departments of Genetics, of Psychiatry, and of Comparative Medicine, Program in Cellular Neuroscience, Neurodegeneration and Repair, Yale Child Study Center, Yale School of Medicine, New Haven, CT, USA.
| | - Arnold Kriegstein
- Department of Neurology and the Eli and Edythe Broad Center for Regeneration Medicine and Stem Cell Research at the University of California, San Francisco, San Francisco, CA, USA.
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47
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Ashwell KWS, Gurovich Y. Quantitative analysis of forebrain pallial morphology in monotremes and comparison with that in therians. ZOOLOGY 2019; 134:38-57. [PMID: 31146906 DOI: 10.1016/j.zool.2019.04.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Revised: 04/02/2019] [Accepted: 04/03/2019] [Indexed: 10/27/2022]
Abstract
We have made quantitative volumetric analyses of cerebral cortical (pallial) structures in the brains of three species of monotreme (Ornithorhynchus anatinus, Tachyglossus aculeatus, Zaglossus bruijni) and compared the findings with similar measurements in a range of therian mammals (6 marsupials and 50 placentals). We have found that although the iso- and periallocortical grey matter volume of the monotremes is about what would be expected for their brain size, the proportion of iso- and periallocortical white matter in monotremes is substantially lower than that in the forebrains of therians. This suggests that the forebrains of the three monotremes have fewer association, commissural and/or projection connections than those of similarly sized forebrains of therian mammals. We also found that the iso- and periallocortex of the platypus is relatively smooth-surfaced compared to similarly sized brains of therian mammals, with a distinct caudal shift in the positioning of cortical white matter in the forebrain, consistent with expansion of the posterior thalamic radiation. Central laminated olfactory structures (anterior olfactory nucleus and piriform cortex) are large in the tachyglossid monotremes (Tachyglossus aculeatus and Zaglossus bruijni) and large in xenarthran placental mammals, suggesting convergence of the forebrain structure of monotreme formivores with that of similarly specialized therians like the xenarthrans Myrmecophaga tridactyla and Dasypus novemcinctus.
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Affiliation(s)
- Ken W S Ashwell
- Department of Anatomy, School of Medical Sciences, The University of New South Wales, 2052, New South Wales, Australia.
| | - Yamila Gurovich
- Department of Anatomy, School of Medical Sciences, The University of New South Wales, 2052, New South Wales, Australia; CIEMEP, CONICET-UNPSJB, Roca 780, Esquel, 9200, Chubut, Argentina.
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48
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Friocourt F, Kozulin P, Belle M, Suárez R, Di‐Poï N, Richards LJ, Giacobini P, Chédotal A. Shared and differential features of Robo3 expression pattern in amniotes. J Comp Neurol 2019; 527:2009-2029. [DOI: 10.1002/cne.24648] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 12/19/2018] [Accepted: 01/21/2019] [Indexed: 12/11/2022]
Affiliation(s)
| | - Peter Kozulin
- The Queensland Brain Institute The University of Queensland Brisbane Queensland Australia
| | - Morgane Belle
- Sorbonne Université, INSERM, CNRS Institut de la Vision Paris France
| | - Rodrigo Suárez
- The Queensland Brain Institute The University of Queensland Brisbane Queensland Australia
| | - Nicolas Di‐Poï
- Research Program in Developmental Biology, Institute of Biotechnology University of Helsinki Helsinki Finland
| | - Linda J. Richards
- The Queensland Brain Institute The University of Queensland Brisbane Queensland Australia
- The School of Biomedical Sciences The University of Queensland Brisbane Queensland Australia
| | - Paolo Giacobini
- University of Lille, UMR‐S 1172, Centre de Recherche Jean‐Pierre AUBERT Lille France
- Laboratory of Development and Plasticity of the Neuroendocrine Brain INSERM, UMR‐S 1172 Lille France
- FHU 1,000 Days for Health School of Medicine Lille France
| | - Alain Chédotal
- Sorbonne Université, INSERM, CNRS Institut de la Vision Paris France
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Affiliation(s)
- Andrea Ravignani
- Artificial Intelligence Lab, Vrije Universiteit Brussel, Brussels, Belgium
- Research Department, Sealcentre Pieterburen, Pieterburen, The Netherlands
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50
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Ocklenburg S. Manual laterality in marsupials. Laterality 2018; 24:1-3. [PMID: 30232929 DOI: 10.1080/1357650x.2018.1524897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Sebastian Ocklenburg
- a Institute of Cognitive Neuroscience, Biopsychology, Department of Psychology, Ruhr-University Bochum , Germany
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