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Qiao M. Deciphering the genetic code of neuronal type connectivity through bilinear modeling. eLife 2024; 12:RP91532. [PMID: 38857169 PMCID: PMC11164534 DOI: 10.7554/elife.91532] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2024] Open
Abstract
Understanding how different neuronal types connect and communicate is critical to interpreting brain function and behavior. However, it has remained a formidable challenge to decipher the genetic underpinnings that dictate the specific connections formed between neuronal types. To address this, we propose a novel bilinear modeling approach that leverages the architecture similar to that of recommendation systems. Our model transforms the gene expressions of presynaptic and postsynaptic neuronal types, obtained from single-cell transcriptomics, into a covariance matrix. The objective is to construct this covariance matrix that closely mirrors a connectivity matrix, derived from connectomic data, reflecting the known anatomical connections between these neuronal types. When tested on a dataset of Caenorhabditis elegans, our model achieved a performance comparable to, if slightly better than, the previously proposed spatial connectome model (SCM) in reconstructing electrical synaptic connectivity based on gene expressions. Through a comparative analysis, our model not only captured all genetic interactions identified by the SCM but also inferred additional ones. Applied to a mouse retinal neuronal dataset, the bilinear model successfully recapitulated recognized connectivity motifs between bipolar cells and retinal ganglion cells, and provided interpretable insights into genetic interactions shaping the connectivity. Specifically, it identified unique genetic signatures associated with different connectivity motifs, including genes important to cell-cell adhesion and synapse formation, highlighting their role in orchestrating specific synaptic connections between these neurons. Our work establishes an innovative computational strategy for decoding the genetic programming of neuronal type connectivity. It not only sets a new benchmark for single-cell transcriptomic analysis of synaptic connections but also paves the way for mechanistic studies of neural circuit assembly and genetic manipulation of circuit wiring.
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Affiliation(s)
- Mu Qiao
- LinkedInMountain ViewUnited States
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2
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Mincheva-Tasheva S, Pfitzner C, Kumar R, Kurtsdotter I, Scherer M, Ritchie T, Muhr J, Gecz J, Thomas PQ. Mapping combinatorial expression of non-clustered protocadherins in the developing brain identifies novel PCDH19-mediated cell adhesion properties. Open Biol 2024; 14:230383. [PMID: 38629124 PMCID: PMC11037505 DOI: 10.1098/rsob.230383] [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: 10/19/2023] [Revised: 01/25/2024] [Accepted: 02/29/2024] [Indexed: 04/19/2024] Open
Abstract
Non-clustered protocadherins (ncPcdhs) are adhesive molecules with spatio-temporally regulated overlapping expression in the developing nervous system. Although their unique role in neurogenesis has been widely studied, their combinatorial role in brain physiology and pathology is poorly understood. Using probabilistic cell typing by in situ sequencing, we demonstrate combinatorial inter- and intra-familial expression of ncPcdhs in the developing mouse cortex and hippocampus, at single-cell resolution. We discovered the combinatorial expression of Protocadherin-19 (Pcdh19), a protein involved in PCDH19-clustering epilepsy, with Pcdh1, Pcdh9 or Cadherin 13 (Cdh13) in excitatory neurons. Using aggregation assays, we demonstrate a code-specific adhesion function of PCDH19; mosaic PCDH19 absence in PCDH19+9 and PCDH19 + CDH13, but not in PCDH19+1 codes, alters cell-cell interaction. Interestingly, we found that PCDH19 as a dominant protein in two heterophilic adhesion codes could promote trans-interaction between them. In addition, we discovered increased CDH13-mediated cell adhesion in the presence of PCDH19, suggesting a potential role of PCDH19 as an adhesion mediator of CDH13. Finally, we demonstrated novel cis-interactions between PCDH19 and PCDH1, PCDH9 and CDH13. These observations suggest that there is a unique combinatorial code with a cell- and region-specific characteristic where a single molecule defines the heterophilic cell-cell adhesion properties of each code.
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Affiliation(s)
- Stefka Mincheva-Tasheva
- School of Biomedicine and Robinson Research Institute,
University of Adelaide, Adelaide, South Australia5005, Australia
- Genome Editing Program, South Australian Health and Medical
Research Institute, Adelaide, South Australia5000, Australia
| | - Chandran Pfitzner
- School of Biomedicine and Robinson Research Institute,
University of Adelaide, Adelaide, South Australia5005, Australia
- Genome Editing Program, South Australian Health and Medical
Research Institute, Adelaide, South Australia5000, Australia
| | - Raman Kumar
- School of Medicine and Robinson Research Institute, University
of Adelaide, Adelaide, South Australia5005, Australia
| | - Idha Kurtsdotter
- Department of Cell and Molecular Biology, Karolinska
Institute, Stockholm, Sweden
| | - Michaela Scherer
- School of Biomedicine and Robinson Research Institute,
University of Adelaide, Adelaide, South Australia5005, Australia
- Genome Editing Program, South Australian Health and Medical
Research Institute, Adelaide, South Australia5000, Australia
| | - Tarin Ritchie
- School of Medicine and Robinson Research Institute, University
of Adelaide, Adelaide, South Australia5005, Australia
| | - Jonas Muhr
- Department of Cell and Molecular Biology, Karolinska
Institute, Stockholm, Sweden
| | - Jozef Gecz
- School of Medicine and Robinson Research Institute, University
of Adelaide, Adelaide, South Australia5005, Australia
- South Australian Health and Medical Research
Institute, Adelaide, 5000 ,
Australia
| | - Paul Q. Thomas
- School of Biomedicine and Robinson Research Institute,
University of Adelaide, Adelaide, South Australia5005, Australia
- Genome Editing Program, South Australian Health and Medical
Research Institute, Adelaide, South Australia5000, Australia
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3
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Martinez AP, Chung AC, Huang S, Bisogni AJ, Lin Y, Cao Y, Williams EO, Kim JY, Yang JY, Lin DM. Pcdh19 mediates olfactory sensory neuron coalescence during postnatal stages and regeneration. iScience 2023; 26:108220. [PMID: 37965156 PMCID: PMC10641745 DOI: 10.1016/j.isci.2023.108220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 07/12/2023] [Accepted: 10/12/2023] [Indexed: 11/16/2023] Open
Abstract
The mouse olfactory system regenerates constantly throughout life. While genes critical for the initial projection of olfactory sensory neurons (OSNs) to the olfactory bulb have been identified, what genes are important for maintaining the olfactory map during regeneration are still unknown. Here we show a mutation in Protocadherin 19 (Pcdh19), a cell adhesion molecule and member of the cadherin superfamily, leads to defects in OSN coalescence during regeneration. Surprisingly, lateral glomeruli were more affected and males in particular showed a more severe phenotype. Single cell analysis unexpectedly showed OSNs expressing the MOR28 odorant receptor could be subdivided into two major clusters. We showed that at least one protocadherin is differentially expressed between OSNs coalescing on the medial and lateral glomeruli. Moreover, females expressed a slightly different complement of genes from males. These features may explain the differential effects of mutating Pcdh19 on medial and lateral glomeruli in males and females.
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Affiliation(s)
- Andrew P. Martinez
- Department of Biomedical Sciences, Cornell University, Ithaca, NY 14850, USA
| | - Alexander C. Chung
- Department of Biomedical Sciences, Cornell University, Ithaca, NY 14850, USA
| | - Suihong Huang
- Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Hong Kong SAR, China
| | - Adam J. Bisogni
- Department of Biomedical Sciences, Cornell University, Ithaca, NY 14850, USA
| | - Yingxin Lin
- School of Mathematics and Statistics, F07 University of Sydney, NSW 2006, Australia
| | - Yue Cao
- School of Mathematics and Statistics, F07 University of Sydney, NSW 2006, Australia
| | - Eric O. Williams
- Department of Biomedical Sciences, Cornell University, Ithaca, NY 14850, USA
| | - Jin Y. Kim
- Department of Biomedical Sciences, City University of Hong Kong, Hong Kong SAR, China
| | - Jean Y.H. Yang
- School of Mathematics and Statistics, F07 University of Sydney, NSW 2006, Australia
| | - David M. Lin
- Department of Biomedical Sciences, Cornell University, Ithaca, NY 14850, USA
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4
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Zhen Y, Pavez M, Li X. The role of Pcdh10 in neurological disease and cancer. J Cancer Res Clin Oncol 2023; 149:8153-8164. [PMID: 37058252 PMCID: PMC10374755 DOI: 10.1007/s00432-023-04743-w] [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: 03/06/2023] [Accepted: 04/03/2023] [Indexed: 04/15/2023]
Abstract
BACKGROUND Protocadherin 10 (PCDH 10), a member of the superfamily of protocadherins, is a Ca2+-dependent homophilic cell-cell adhesion molecule expressed on the surface of cell membranes. Protocadherin 10 plays a critical role in the central nervous system including in cell adhesion, formation and maintenance of neural circuits and synapses, regulation of actin assembly, cognitive function and tumor suppression. Additionally, Pcdh10 can serve as a non-invasive diagnostic and prognostic indicator for various cancers. METHODS This paper collects and reviews relevant literature in Pubmed. CONCLUSION This review describes the latest research understanding the role of Pcdh10 in neurological disease and human cancer, highlighting the importance of scrutinizing its properties for the development of targeted therapies and identifying a need for further research to explore Pcdh10 functions in other pathways, cell types and human pathologies.
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Affiliation(s)
- Yilan Zhen
- Menzies Institute for Medical Research, University of Tasmania, Liverpool street, Hobart, 7000, Australia
| | - Macarena Pavez
- Department of Anatomy, University of Otago, Dunedin, Otago, New Zealand.
| | - Xinying Li
- Department of Oncology, The First Affiliated Hospital of Anhui Medical University, Hefei, People's Republic of China.
- School of Life Sciences, Anhui Medical University, Hefei, People's Republic of China.
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5
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Hudson JD, Tamilselvan E, Sotomayor M, Cooper SR. A complete Protocadherin-19 ectodomain model for evaluating epilepsy-causing mutations and potential protein interaction sites. Structure 2021; 29:1128-1143.e4. [PMID: 34520737 DOI: 10.1016/j.str.2021.07.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 05/22/2021] [Accepted: 07/21/2021] [Indexed: 11/26/2022]
Abstract
Cadherin superfamily members play a critical role in differential adhesion during neurodevelopment, and their disruption has been linked to several neurodevelopmental disorders. Mutations in protocadherin-19 (PCDH19), a member of the δ-protocadherin subfamily of cadherins, cause a unique form of epilepsy called PCDH19 clustering epilepsy. While PCDH19 and other non-clustered δ-protocadherins form multimers with other members of the cadherin superfamily to alter adhesiveness, the specific protein surfaces responsible for these interactions are unknown. Only portions of the PCDH19 extracellular domain structure had been solved previously. Here, we present a structure of the missing segment from zebrafish Protocadherin-19 (Pcdh19) and create a complete ectodomain model. This model shows the structural environment for 97% of disease-causing missense mutations and reveals two potential surfaces for intermolecular interactions that could modify Pcdh19's adhesive strength and specificity.
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Affiliation(s)
- Jonathan D Hudson
- Department of Science and Mathematics, Cedarville University, 251 N. Main Street, Cedarville, OH 45314, USA
| | - Elakkiya Tamilselvan
- Department of Chemistry and Biochemistry, The Ohio State University, 484 W. 12th Avenue, Columbus, OH 43210, USA; Biophysics Graduate Program, The Ohio State University, 484 W. 12th Avenue, Columbus, OH 43210, USA
| | - Marcos Sotomayor
- Department of Chemistry and Biochemistry, The Ohio State University, 484 W. 12th Avenue, Columbus, OH 43210, USA; Biophysics Graduate Program, The Ohio State University, 484 W. 12th Avenue, Columbus, OH 43210, USA
| | - Sharon R Cooper
- Department of Science and Mathematics, Cedarville University, 251 N. Main Street, Cedarville, OH 45314, USA.
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6
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Shohayeb B, Cooper HM. Mosaic synapses in epilepsy. Science 2021; 372:235-236. [PMID: 33859020 DOI: 10.1126/science.abh3555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Affiliation(s)
- Belal Shohayeb
- Queensland Brain Institute, University of Queensland, Brisbane, Queensland, Australia.
| | - Helen M Cooper
- Queensland Brain Institute, University of Queensland, Brisbane, Queensland, Australia.
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7
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Gray ME, Sotomayor M. Crystal structure of the nonclassical cadherin-17 N-terminus and implications for its adhesive binding mechanism. Acta Crystallogr F Struct Biol Commun 2021; 77:85-94. [PMID: 33682793 PMCID: PMC7938635 DOI: 10.1107/s2053230x21002247] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 02/25/2021] [Indexed: 12/27/2022] Open
Abstract
The cadherin superfamily of calcium-dependent cell-adhesion proteins has over 100 members in the human genome. All members of the superfamily feature at least a pair of extracellular cadherin (EC) repeats with calcium-binding sites in the EC linker region. The EC repeats across family members form distinct complexes that mediate cellular adhesion. For instance, classical cadherins (five EC repeats) strand-swap their N-termini and exchange tryptophan residues in EC1, while the clustered protocadherins (six EC repeats) use an extended antiparallel `forearm handshake' involving repeats EC1-EC4. The 7D-cadherins, cadherin-16 (CDH16) and cadherin-17 (CDH17), are the most similar to classical cadherins and have seven EC repeats, two of which are likely to have arisen from gene duplication of EC1-2 from a classical ancestor. However, CDH16 and CDH17 lack the EC1 tryptophan residue used by classical cadherins to mediate adhesion. The structure of human CDH17 EC1-2 presented here reveals features that are not seen in classical cadherins and that are incompatible with the EC1 strand-swap mechanism for adhesion. Analyses of crystal contacts, predicted glycosylation and disease-related mutations are presented along with sequence alignments suggesting that the novel features in the CDH17 EC1-2 structure are well conserved. These results hint at distinct adhesive properties for 7D-cadherins.
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Affiliation(s)
- Michelle E. Gray
- Department of Chemistry and Biochemistry, The Ohio State University, 484 West 12th Avenue, Columbus, OH 43210, USA
| | - Marcos Sotomayor
- Department of Chemistry and Biochemistry, The Ohio State University, 484 West 12th Avenue, Columbus, OH 43210, USA
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8
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Pancho A, Aerts T, Mitsogiannis MD, Seuntjens E. Protocadherins at the Crossroad of Signaling Pathways. Front Mol Neurosci 2020; 13:117. [PMID: 32694982 PMCID: PMC7339444 DOI: 10.3389/fnmol.2020.00117] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 06/08/2020] [Indexed: 12/25/2022] Open
Abstract
Protocadherins (Pcdhs) are cell adhesion molecules that belong to the cadherin superfamily, and are subdivided into clustered (cPcdhs) and non-clustered Pcdhs (ncPcdhs) in vertebrates. In this review, we summarize their discovery, expression mechanisms, and roles in neuronal development and cancer, thereby highlighting the context-dependent nature of their actions. We furthermore provide an extensive overview of current structural knowledge, and its implications concerning extracellular interactions between cPcdhs, ncPcdhs, and classical cadherins. Next, we survey the known molecular action mechanisms of Pcdhs, emphasizing the regulatory functions of proteolytic processing and domain shedding. In addition, we outline the importance of Pcdh intracellular domains in the regulation of downstream signaling cascades, and we describe putative Pcdh interactions with intracellular molecules including components of the WAVE complex, the Wnt pathway, and apoptotic cascades. Our overview combines molecular interaction data from different contexts, such as neural development and cancer. This comprehensive approach reveals potential common Pcdh signaling hubs, and points out future directions for research. Functional studies of such key factors within the context of neural development might yield innovative insights into the molecular etiology of Pcdh-related neurodevelopmental disorders.
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Affiliation(s)
- Anna Pancho
- Laboratory of Developmental Neurobiology, Department of Biology, KU Leuven, Leuven, Belgium
| | - Tania Aerts
- Laboratory of Developmental Neurobiology, Department of Biology, KU Leuven, Leuven, Belgium
| | - Manuela D Mitsogiannis
- Laboratory of Developmental Neurobiology, Department of Biology, KU Leuven, Leuven, Belgium
| | - Eve Seuntjens
- Laboratory of Developmental Neurobiology, Department of Biology, KU Leuven, Leuven, Belgium
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9
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Ponroy Bally B, Farmer WT, Jones EV, Jessa S, Kacerovsky JB, Mayran A, Peng H, Lefebvre JL, Drouin J, Hayer A, Ernst C, Murai KK. Human iPSC-derived Down syndrome astrocytes display genome-wide perturbations in gene expression, an altered adhesion profile, and increased cellular dynamics. Hum Mol Genet 2020; 29:785-802. [PMID: 31943018 PMCID: PMC7104679 DOI: 10.1093/hmg/ddaa003] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 12/31/2019] [Accepted: 01/10/2020] [Indexed: 12/15/2022] Open
Abstract
Down syndrome (DS), caused by the triplication of human chromosome 21, leads to significant alterations in brain development and is a major genetic cause of intellectual disability. While much is known about changes to neurons in DS, the effects of trisomy 21 on non-neuronal cells such as astrocytes are poorly understood. Astrocytes are critical for brain development and function, and their alteration may contribute to DS pathophysiology. To better understand the impact of trisomy 21 on astrocytes, we performed RNA-sequencing on astrocytes from newly produced DS human induced pluripotent stem cells (hiPSCs). While chromosome 21 genes were upregulated in DS astrocytes, we found consistent up- and down-regulation of genes across the genome with a strong dysregulation of neurodevelopmental, cell adhesion and extracellular matrix molecules. ATAC (assay for transposase-accessible chromatin)-seq also revealed a global alteration in chromatin state in DS astrocytes, showing modified chromatin accessibility at promoters of cell adhesion and extracellular matrix genes. Along with these transcriptomic and epigenomic changes, DS astrocytes displayed perturbations in cell size and cell spreading as well as modifications to cell-cell and cell-substrate recognition/adhesion, and increases in cellular motility and dynamics. Thus, triplication of chromosome 21 is associated with genome-wide transcriptional, epigenomic and functional alterations in astrocytes that may contribute to altered brain development and function in DS.
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Affiliation(s)
- Blandine Ponroy Bally
- Department of Neurology & Neurosurgery, Brain Repair and Integrative Neuroscience Program, Centre for Research in Neuroscience, Research Institute of the McGill University Health Centre, Montreal, QC H3G 1A4, Canada
| | - W Todd Farmer
- Department of Neurology & Neurosurgery, Brain Repair and Integrative Neuroscience Program, Centre for Research in Neuroscience, Research Institute of the McGill University Health Centre, Montreal, QC H3G 1A4, Canada
| | - Emma V Jones
- Department of Neurology & Neurosurgery, Brain Repair and Integrative Neuroscience Program, Centre for Research in Neuroscience, Research Institute of the McGill University Health Centre, Montreal, QC H3G 1A4, Canada
| | - Selin Jessa
- Department of Neurology & Neurosurgery, Brain Repair and Integrative Neuroscience Program, Centre for Research in Neuroscience, Research Institute of the McGill University Health Centre, Montreal, QC H3G 1A4, Canada
- Quantitative Life Sciences, McGill University, Montreal, QC H3A 2A7, Canada
| | - J Benjamin Kacerovsky
- Department of Neurology & Neurosurgery, Brain Repair and Integrative Neuroscience Program, Centre for Research in Neuroscience, Research Institute of the McGill University Health Centre, Montreal, QC H3G 1A4, Canada
| | - Alexandre Mayran
- Institut de Recherches Cliniques de Montréal (IRCM), Montreal, QC H2W 1R7, Canada
| | - Huashan Peng
- Department of Psychiatry, McGill University, Montreal, QC H4H 1R3, Canada
- Department of Human Genetics, McGill University, Montreal, QC H4H 1R3, Canada
- Douglas Hospital Research Institute, Verdun, QC H4H 1R3, Canada
| | - Julie L Lefebvre
- Department of Molecular Genetics, Program for Neuroscience and Mental Health, Hospital for Sick Children, University of Toronto, Toronto, ON M5G 0A4, Canada
| | - Jacques Drouin
- Institut de Recherches Cliniques de Montréal (IRCM), Montreal, QC H2W 1R7, Canada
| | - Arnold Hayer
- Department of Biology, McGill University, Bellini Life Sciences Complex, Montreal, QC H3G 0B1, Canada
| | - Carl Ernst
- Department of Psychiatry, McGill University, Montreal, QC H4H 1R3, Canada
- Department of Human Genetics, McGill University, Montreal, QC H4H 1R3, Canada
- Douglas Hospital Research Institute, Verdun, QC H4H 1R3, Canada
| | - Keith K Murai
- Department of Neurology & Neurosurgery, Brain Repair and Integrative Neuroscience Program, Centre for Research in Neuroscience, Research Institute of the McGill University Health Centre, Montreal, QC H3G 1A4, Canada
- Quantitative Life Sciences, McGill University, Montreal, QC H3A 2A7, Canada
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10
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Family-wide Structural and Biophysical Analysis of Binding Interactions among Non-clustered δ-Protocadherins. Cell Rep 2020; 30:2655-2671.e7. [PMID: 32101743 PMCID: PMC7082078 DOI: 10.1016/j.celrep.2020.02.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2019] [Revised: 11/02/2019] [Accepted: 01/31/2020] [Indexed: 01/21/2023] Open
Abstract
Non-clustered δ1- and δ2-protocadherins, close relatives of clustered protocadherins, function in cell adhesion and motility and play essential roles in neural patterning. To understand the molecular interactions underlying these functions, we used solution biophysics to characterize binding of δ1- and δ2-protocadherins, determined crystal structures of ectodomain complexes from each family, and assessed ectodomain assembly in reconstituted intermembrane junctions by cryoelectron tomography (cryo-ET). Homophilic trans (cell-cell) interactions were preferred for all δ-protocadherins, with additional weaker heterophilic interactions observed exclusively within each subfamily. As expected, δ1- and δ2-protocadherin trans dimers formed through antiparallel EC1-EC4 interfaces, like clustered protocadherins. However, no ectodomain-mediated cis (same-cell) interactions were detectable in solution; consistent with this, cryo-ET of reconstituted junctions revealed dense assemblies lacking the characteristic order observed for clustered protocadherins. Our results define non-clustered protocadherin binding properties and their structural basis, providing a foundation for interpreting their functional roles in neural patterning.
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11
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Miralles CP, Taylor MJ, Bear J, Fekete CD, George S, Li Y, Bonhomme B, Chiou TT, De Blas AL. Expression of protocadherin-γC4 protein in the rat brain. J Comp Neurol 2019; 528:840-864. [PMID: 31609469 DOI: 10.1002/cne.24783] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Revised: 09/24/2019] [Accepted: 09/30/2019] [Indexed: 12/26/2022]
Abstract
It has been proposed that the combinatorial expression of γ-protocadherins (Pcdh-γs) and other clustered protocadherins (Pcdhs) provides a code of molecular identity and individuality to neurons, which plays a major role in the establishment of specific synaptic connectivity and formation of neuronal circuits. Particular attention has been directed to the Pcdh-γ family, for which experimental evidence derived from Pcdh-γ-deficient mice shows that they are involved in dendrite self-avoidance, synapse development, dendritic arborization, spine maturation, and prevention of apoptosis of some neurons. Moreover, a triple-mutant mouse deficient in the three C-type members of the Pcdh-γ family (Pcdh-γC3, Pcdh-γC4, and Pcdh-γC5) shows a phenotype similar to the mouse deficient in whole Pcdh-γ family, indicating that the latter is largely due to the absence of C-type Pcdh-γs. The role of each individual C-type Pcdh-γ is not known. We have developed a specific antibody to Pcdh-γC4 to reveal the expression of this protein in the rat brain. The results show that although Pcdh-γC4 is expressed at higher levels in the embryo and earlier postnatal weeks, it is also expressed in the adult rat brain. Pcdh-γC4 is expressed in both neurons and astrocytes. In the adult brain, the regional distribution of Pcdh-γC4 immunoreactivity is similar to that of Pcdh-γC4 mRNA, being highest in the olfactory bulb, dentate gyrus, and cerebellum. Pcdh-γC4 forms puncta that are frequently apposed to glutamatergic and GABAergic synapses. They are also frequently associated with neuron-astrocyte contacts. The results provide new insights into the cell recognition function of Pcdh-γC4 in neurons and astrocytes.
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Affiliation(s)
- Celia P Miralles
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut, USA
| | - Michael J Taylor
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut, USA
| | - John Bear
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut, USA
| | - Christopher D Fekete
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut, USA
| | - Shanu George
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut, USA
| | - Yanfang Li
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut, USA
| | - Bevan Bonhomme
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut, USA
| | - Tzu-Ting Chiou
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut, USA
| | - Angel L De Blas
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, Connecticut, USA
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12
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Multiplane Calcium Imaging Reveals Disrupted Development of Network Topology in Zebrafish pcdh19 Mutants. eNeuro 2019; 6:ENEURO.0420-18.2019. [PMID: 31061071 PMCID: PMC6525332 DOI: 10.1523/eneuro.0420-18.2019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Revised: 04/23/2019] [Accepted: 04/24/2019] [Indexed: 12/18/2022] Open
Abstract
Functional brain networks self-assemble during development, although the molecular basis of network assembly is poorly understood. Protocadherin-19 (pcdh19) is a homophilic cell adhesion molecule that is linked to neurodevelopmental disorders, and influences multiple cellular and developmental events in zebrafish. Although loss of PCDH19 in humans and model organisms leads to functional deficits, the underlying network defects remain unknown. Here, we employ multiplane, resonant-scanning in vivo two-photon calcium imaging of developing zebrafish, and use graph theory to characterize the development of resting state functional networks in both wild-type and pcdh19 mutant larvae. We find that the brain networks of pcdh19 mutants display enhanced clustering and an altered developmental trajectory of network assembly. Our results show that functional imaging and network analysis in zebrafish larvae is an effective approach for characterizing the developmental impact of lesions in genes of clinical interest.
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13
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Zhao C, Zhang C, Xing Z, Ahmad Z, Li JS, Chang MW. Pharmacological effects of natural Ganoderma and its extracts on neurological diseases: A comprehensive review. Int J Biol Macromol 2019; 121:1160-1178. [DOI: 10.1016/j.ijbiomac.2018.10.076] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Revised: 10/06/2018] [Accepted: 10/14/2018] [Indexed: 01/13/2023]
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14
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Bisogni AJ, Ghazanfar S, Williams EO, Marsh HM, Yang JY, Lin DM. Tuning of delta-protocadherin adhesion through combinatorial diversity. eLife 2018; 7:41050. [PMID: 30547884 PMCID: PMC6326727 DOI: 10.7554/elife.41050] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Accepted: 12/11/2018] [Indexed: 12/21/2022] Open
Abstract
The delta-protocadherins (δ-Pcdhs) play key roles in neural development, and expression studies suggest they are expressed in combination within neurons. The extent of this combinatorial diversity, and how these combinations influence cell adhesion, is poorly understood. We show that individual mouse olfactory sensory neurons express 0–7 δ-Pcdhs. Despite this apparent combinatorial complexity, K562 cell aggregation assays revealed simple principles that mediate tuning of δ-Pcdh adhesion. Cells can vary the number of δ-Pcdhs expressed, the level of surface expression, and which δ-Pcdhs are expressed, as different members possess distinct apparent adhesive affinities. These principles contrast with those identified previously for the clustered protocadherins (cPcdhs), where the particular combination of cPcdhs expressed does not appear to be a critical factor. Despite these differences, we show δ-Pcdhs can modify cPcdh adhesion. Our studies show how intra- and interfamily interactions can greatly amplify the impact of this small subfamily on neuronal function. Multicellular life depends on cells being able to stick together. The human body, for example, consists of trillions of cells grouped into tissues and organs. The brain alone contains some 87 billion neurons organized into complex networks. To stay together, cells use proteins on their surface called cell adhesion molecules (CAMs). There are four major families of CAMs, each with multiple members, and the CAMs on one cell recognize and interact with the CAMs on another. But how does this process work? One possibility is that different combinations of CAMs allow different cells to stick together. Bisogni et al. tested this idea by studying a family of CAMs called the delta-protocadherins. This family has nine members, each with its own gene. Before cells can use a gene to produce a protein, they must first use the gene’s DNA as a template to build an RNA molecule. By counting the number of different types of RNA molecules inside individual cells, Bisogni et al. showed that sensory neurons in the mouse each produce up to seven different delta-protocadherins. Further experiments revealed that cells fine-tune their interactions by varying the number, type and combination of delta-protocadherins on their surface. In addition, the delta-protocadherins also alter interactions between members of a related gene family, the clustered protocadherins. This further increases their ability to regulate how cells interact. In contrast to previous studies that focused on single molecules, Bisogni et al. have shown how combinations of molecules work together to influence cell adhesion. Deciphering this combinatorial code is key to understanding how interactions between cells go awry in disease. Mutations in the genes for CAMs often impair brain development. The reported findings may provide insights into how such mutations disrupt the CAM combinatorial code and alter cell to cell interactions.
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Affiliation(s)
- Adam J Bisogni
- Department of Biomedical Sciences, Cornell University, Ithaca, United States
| | - Shila Ghazanfar
- School of Mathematics and Statistics, The University of Sydney, Sydney, Australia
| | - Eric O Williams
- Department of Biomedical Sciences, Cornell University, Ithaca, United States.,Department of Biology and Chemistry, Fitchburg State University, Fitchburg, United States
| | - Heather M Marsh
- Department of Biomedical Sciences, Cornell University, Ithaca, United States
| | - Jean Yh Yang
- School of Mathematics and Statistics, The University of Sydney, Sydney, Australia
| | - David M Lin
- Department of Biomedical Sciences, Cornell University, Ithaca, United States
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15
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Mah KM, Weiner JA. Regulation of Wnt signaling by protocadherins. Semin Cell Dev Biol 2017; 69:158-171. [PMID: 28774578 PMCID: PMC5586504 DOI: 10.1016/j.semcdb.2017.07.043] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 07/21/2017] [Accepted: 07/28/2017] [Indexed: 12/23/2022]
Abstract
The ∼70 protocadherins comprise the largest group within the cadherin superfamily. Their diversity, the complexity of the mechanisms through which their genes are regulated, and their many critical functions in nervous system development have engendered a growing interest in elucidating the intracellular signaling pathways through which they act. Recently, multiple protocadherins across several subfamilies have been implicated as modulators of Wnt signaling pathways, and through this as potential tumor suppressors. Here, we review the extant data on the regulation by protocadherins of Wnt signaling pathways and components, and highlight some key unanswered questions that could shape future research.
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Affiliation(s)
- Kar Men Mah
- Department of Biology, The University of Iowa, Iowa City, IA, USA.
| | - Joshua A Weiner
- Department of Biology, The University of Iowa, Iowa City, IA, USA; Department of Psychiatry, The University of Iowa, Iowa City, IA, USA; Iowa Neuroscience Institute, The University of Iowa, Iowa City, IA, USA.
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