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Fischer F, Ernst L, Frey A, Holstein K, Prasad D, Weichselberger V, Balaji R, Classen AK. A mismatch in the expression of cell surface molecules induces tissue-intrinsic defense against aberrant cells. Curr Biol 2024; 34:980-996.e6. [PMID: 38350446 DOI: 10.1016/j.cub.2024.01.053] [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: 03/09/2023] [Revised: 09/29/2023] [Accepted: 01/19/2024] [Indexed: 02/15/2024]
Abstract
Tissue-intrinsic error correction enables epithelial cells to detect abnormal neighboring cells and facilitate their removal from the tissue. One of these pathways, "interface surveillance," is triggered by cells with aberrant developmental and cell-fate-patterning pathways. It remains unknown which molecular mechanisms provide cells with the ability to compare fate between neighboring cells. We demonstrate that Drosophila imaginal discs express an array of cell surface molecules previously implicated in neuronal axon guidance processes. They include members of the Robo, Teneurin, Ephrin, Toll-like, or atypical cadherin families. Importantly, a mismatch in expression levels of these cell surface molecules between adjacent cells is sufficient to induce interface surveillance, indicating that differences in expression levels between neighboring cells, rather than their absolute expression levels, are crucial. Specifically, a mismatch in Robo2 and Robo3, but not Robo1, induces enrichment of actin, myosin II, and Ena/Vasp, as well as activation of JNK and apoptosis at clonal interfaces. Moreover, Robo2 can induce interface surveillance independently of its cytosolic domain and without the need for the Robo-ligand Slit. The expression of Robo2 and other cell surface molecules, such as Teneurins or the Ephrin receptor is regulated by fate-patterning pathways intrinsic and extrinsic to the wing disc, as well as by expression of oncogenic RasV12. Combined, we demonstrate that neighboring cells respond to a mismatch in surface code patterns mediated by specific transmembrane proteins and reveal a novel function for these cell surface proteins in cell fate recognition and removal of aberrant cells during development and homeostasis of epithelial tissues.
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Affiliation(s)
- Friedericke Fischer
- Hilde-Mangold-Haus, University of Freiburg, 79104 Freiburg, Germany; Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany; International Max Planck Research School for Immunobiology, Epigenetics, and Metabolism, 79108 Freiburg, Germany
| | - Laurin Ernst
- Hilde-Mangold-Haus, University of Freiburg, 79104 Freiburg, Germany; Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany; International Max Planck Research School for Immunobiology, Epigenetics, and Metabolism, 79108 Freiburg, Germany
| | - Anna Frey
- Hilde-Mangold-Haus, University of Freiburg, 79104 Freiburg, Germany; Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany; Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, 79104 Freiburg, Germany
| | - Katrin Holstein
- Department of Vascular Cell Biology, Max Planck Institute for Molecular Biomedicine, 48149 Münster, Germany
| | - Deepti Prasad
- Hilde-Mangold-Haus, University of Freiburg, 79104 Freiburg, Germany; Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany; Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, 79104 Freiburg, Germany
| | - Vanessa Weichselberger
- Spemann Graduate School of Biology and Medicine (SGBM), University of Freiburg, 79104 Freiburg, Germany; Aix Marseille University, CNRS, UMR 7288, IBDM, 13288 Marseille, France
| | - Ramya Balaji
- Hilde-Mangold-Haus, University of Freiburg, 79104 Freiburg, Germany; Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany
| | - Anne-Kathrin Classen
- Hilde-Mangold-Haus, University of Freiburg, 79104 Freiburg, Germany; Faculty of Biology, University of Freiburg, 79104 Freiburg, Germany; CIBSS Centre for Integrative Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany; BIOSS Centre for Biological Signalling Studies, University of Freiburg, 79104 Freiburg, Germany.
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2
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Abdel-Rahman SA, Gabr M. Small Molecule Immunomodulators as Next-Generation Therapeutics for Glioblastoma. Cancers (Basel) 2024; 16:435. [PMID: 38275876 PMCID: PMC10814352 DOI: 10.3390/cancers16020435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 01/14/2024] [Accepted: 01/18/2024] [Indexed: 01/27/2024] Open
Abstract
Glioblastoma (GBM), the most aggressive astrocytic glioma, remains a therapeutic challenge despite multimodal approaches. Immunotherapy holds promise, but its efficacy is hindered by the highly immunosuppressive GBM microenvironment. This review underscores the urgent need to comprehend the intricate interactions between glioma and immune cells, shaping the immunosuppressive tumor microenvironment (TME) in GBM. Immunotherapeutic advancements have shown limited success, prompting exploration of immunomodulatory approaches targeting tumor-associated macrophages (TAMs) and microglia, constituting a substantial portion of the GBM TME. Converting protumor M2-like TAMs to antitumor M1-like phenotypes emerges as a potential therapeutic strategy for GBM. The blood-brain barrier (BBB) poses an additional challenge to successful immunotherapy, restricting drug delivery to GBM TME. Research efforts to enhance BBB permeability have mainly focused on small molecules, which can traverse the BBB more effectively than biologics. Despite over 200 clinical trials for GBM, studies on small molecule immunomodulators within the GBM TME are scarce. Developing small molecules with optimal brain penetration and selectivity against immunomodulatory pathways presents a promising avenue for combination therapies in GBM. This comprehensive review discusses various immunomodulatory pathways in GBM progression with a focus on immune checkpoints and TAM-related targets. The exploration of such molecules, with the capacity to selectively target key immunomodulatory pathways and penetrate the BBB, holds the key to unlocking new combination therapy approaches for GBM.
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Affiliation(s)
- Somaya A. Abdel-Rahman
- Department of Radiology, Molecular Imaging Innovations Institute (MI3), Weill Cornell Medicine, New York, NY 10065, USA
- Department of Medicinal Chemistry, Faculty of Pharmacy, Mansoura University, Mansoura 35516, Egypt
| | - Moustafa Gabr
- Department of Radiology, Molecular Imaging Innovations Institute (MI3), Weill Cornell Medicine, New York, NY 10065, USA
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3
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Wang Y, Yang J, Hu F, Yang Y, Huang K, Zhang K. Cryo-EM reveals how the mastigoneme assembles and responds to environmental signal changes. J Cell Biol 2023; 222:e202301066. [PMID: 37882754 PMCID: PMC10602792 DOI: 10.1083/jcb.202301066] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Revised: 08/24/2023] [Accepted: 09/19/2023] [Indexed: 10/27/2023] Open
Abstract
Mastigonemes are thread-like structures adorning the flagella of protists. In Chlamydomonas reinhardtii, filamentous mastigonemes find their roots in the flagella's distal region, associated with the channel protein PKD2, implying their potential contribution to external signal sensing and flagellar motility control. Here, we present the single-particle cryo-electron microscopy structure of the mastigoneme at 3.4 Å. The filament unit, MST1, consists of nine immunoglobulin-like domains and six Sushi domains, trailed by an elastic polyproline-II helix. Our structure demonstrates that MST1 subunits are periodically assembled to form a centrosymmetric, non-polar filament. Intriguingly, numerous clustered disulfide bonds within a ladder-like spiral configuration underscore structural resilience. While defects in the mastigoneme structure did not noticeably affect general attributes of cell swimming, they did impact specific swimming properties, particularly under varied environmental conditions such as redox shifts and heightened viscosity. Our findings illuminate the potential role of mastigonemes in flagellar motility and suggest their involvement in diverse environmental responses.
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Affiliation(s)
- Yue Wang
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Jun Yang
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Fangheng Hu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Yuchen Yang
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Kaiyao Huang
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
| | - Kai Zhang
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
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4
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Liu Z, Huang W, Zhu M, Xu Z, Xu Z, Yu C, Huang H. Mechanism of Robo1 in the pentylenetetrazol-kindled epilepsy mouse model. IBRAIN 2023; 9:369-380. [PMID: 38680506 PMCID: PMC11045194 DOI: 10.1002/ibra.12127] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 08/02/2023] [Accepted: 08/04/2023] [Indexed: 04/28/2024]
Abstract
The neural network hypothesis is one of the important pathogenesis of drug-resistant epilepsy. Axons guide molecules through synaptic remodeling and brain tissue remodeling, which may result in the formation of abnormal neural networks. Therefore, axon guidance plays a crucial role in disease progression. However, although Robo1 is one of the important components of axon guidance, the role of Robo1 in epilepsy remains unclear. In this study, we aimed to explore the mechanism of Robo1 in epilepsy. Male adult C57BL/6 mice were intraperitoneally injected with pentylenetetrazol to establish an epilepsy model. Lentivirus (LV) was given via intracranial injection 2 weeks before pentylenetetrazol injection. Different expressions of Robo1 between the control group, LV-mediated Robo1 short hairpin RNA group, empty vector control LV group, and normal saline group were analyzed using Western blot, immunofluorescence staining, Golgi staining, and video monitoring. Robo1 was increased in the hippocampus in the pentylenetetrazol-induced epilepsy mouse model; lentiviral Robo1 knockdown prolonged the latency of seizure and reduced the seizure grade in mice and resulted in a decrease in dendritic spine density, while the number of mature dendritic spines was maintained. We speculate that Robo1 has been implicated in the development and progression of epilepsy through its effects on dendritic spine morphology and density. Epileptic mice with Robo1 knockdown virus intervention had lower seizure grade and longer latency. Follow-up findings suggest that Robo1 may modulate seizures by affecting dendritic spine density and morphology. Downregulation of Robo1 may negatively regulate epileptogenesis by decreasing the density of dendritic spines and maintaining a greater number of mature dendritic spines.
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Affiliation(s)
- Zheng Liu
- Department of NeurologyAffiliated Hospital of Zunyi Medical UniversityZunyiChina
| | - Wei Huang
- Department of NeurologyAffiliated Hospital of Zunyi Medical UniversityZunyiChina
| | - Man‐Min Zhu
- Department of NeurologyAffiliated Hospital of Zunyi Medical UniversityZunyiChina
| | - Zhong‐Xiang Xu
- Department of NeurologyAffiliated Hospital of Zunyi Medical UniversityZunyiChina
| | - Zu‐Cai Xu
- Department of NeurologyAffiliated Hospital of Zunyi Medical UniversityZunyiChina
| | - Chang‐Yin Yu
- Department of NeurologyAffiliated Hospital of Zunyi Medical UniversityZunyiChina
| | - Hao Huang
- Department of NeurologyAffiliated Hospital of Zunyi Medical UniversityZunyiChina
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5
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Feng L, Shu HP, Sun LL, Tu YC, Liao QQ, Yao LJ. Role of the SLIT-ROBO signaling pathway in renal pathophysiology and various renal diseases. Front Physiol 2023; 14:1226341. [PMID: 37497439 PMCID: PMC10366692 DOI: 10.3389/fphys.2023.1226341] [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: 05/21/2023] [Accepted: 06/30/2023] [Indexed: 07/28/2023] Open
Abstract
SLIT ligand and its receptor ROBO were initially recognized for their role in axon guidance in central nervous system development. In recent years, as research has advanced, the role of the SLIT-ROBO signaling pathway has gradually expanded from axonal repulsion to cell migration, tumor development, angiogenesis, and bone metabolism. As a secreted protein, SLIT regulates various pathophysiological processes in the kidney, such as proinflammatory responses and fibrosis progression. Many studies have shown that SLIT-ROBO is extensively involved in various aspects of kidney development and maintenance of structure and function. The SLIT-ROBO signaling pathway also plays an important role in different types of kidney disease. This article reviews the advances in the study of the SLIT-ROBO pathway in various renal pathophysiological and kidney disorders and proposes new directions for further research in this field.
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6
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Cortés E, Pak JS, Özkan E. Structure and evolution of neuronal wiring receptors and ligands. Dev Dyn 2023; 252:27-60. [PMID: 35727136 PMCID: PMC10084454 DOI: 10.1002/dvdy.512] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 06/13/2022] [Accepted: 06/14/2022] [Indexed: 01/04/2023] Open
Abstract
One of the fundamental properties of a neuronal circuit is the map of its connections. The cellular and developmental processes that allow for the growth of axons and dendrites, selection of synaptic targets, and formation of functional synapses use neuronal surface receptors and their interactions with other surface receptors, secreted ligands, and matrix molecules. Spatiotemporal regulation of the expression of these receptors and cues allows for specificity in the developmental pathways that wire stereotyped circuits. The families of molecules controlling axon guidance and synapse formation are generally conserved across animals, with some important exceptions, which have consequences for neuronal connectivity. Here, we summarize the distribution of such molecules across multiple taxa, with a focus on model organisms, evolutionary processes that led to the multitude of such molecules, and functional consequences for the diversification or loss of these receptors.
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Affiliation(s)
- Elena Cortés
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, USA.,The Neuroscience Institute, University of Chicago, Chicago, Illinois, USA
| | - Joseph S Pak
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, USA.,The Neuroscience Institute, University of Chicago, Chicago, Illinois, USA
| | - Engin Özkan
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, Illinois, USA.,The Neuroscience Institute, University of Chicago, Chicago, Illinois, USA
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7
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NMR analysis suggests the terminal domains of Robo1 remain extended but are rigidified in the presence of heparan sulfate. Sci Rep 2022; 12:14769. [PMID: 36042257 PMCID: PMC9427851 DOI: 10.1038/s41598-022-18769-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 08/18/2022] [Indexed: 11/19/2022] Open
Abstract
Human roundabout 1 (hRobo1) is an extracellular receptor glycoprotein that plays important roles in angiogenesis, organ development, and tumor progression. Interaction between hRobo1 and heparan sulfate (HS) has been shown to be essential for its biological activity. To better understand the effect of HS binding we engineered a lanthanide-binding peptide sequence (Loop) into the Ig2 domain of hRobo1. Native mass spectrometry was used to verify that loop introduction did not inhibit HS binding or conformational changes previously suggested by gas phase ion mobility measurements. NMR experiments measuring long-range pseudocontact shifts were then performed on 13C-methyl labeled hRobo1-Ig1-2-Loop in HS-bound and unbound forms. The magnitude of most PCSs for methyl groups in the Ig1 domain increase in the bound state confirming a change in the distribution of interdomain geometries. A grid search over Ig1 orientations to optimize the fit of data to a single conformer for both forms produced two similar structures, both of which differ from existing X-ray crystal structures and structures inferred from gas-phase ion mobility measurements. The structures and degree of fit suggest that the hRobo1-Ig1-2 structure changes slightly and becomes more rigid on HS binding. This may have implications for Robo-Slit signaling.
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8
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Huang Y, Ma M, Mao X, Pehlivan D, Kanca O, Un-Candan F, Shu L, Akay G, Mitani T, Lu S, Candan S, Wang H, Xiao B, Lupski JR, Bellen HJ. Novel dominant and recessive variants in human ROBO1 cause distinct neurodevelopmental defects through different mechanisms. Hum Mol Genet 2022; 31:2751-2765. [PMID: 35348658 PMCID: PMC9402236 DOI: 10.1093/hmg/ddac070] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 03/17/2022] [Accepted: 03/20/2022] [Indexed: 07/27/2023] Open
Abstract
The Roundabout (Robo) receptors, located on growth cones of neurons, induce axon repulsion in response to the extracellular ligand Slit. The Robo family of proteins controls midline crossing of commissural neurons during development in flies. Mono- and bi-allelic variants in human ROBO1 (HGNC: 10249) have been associated with incomplete penetrance and variable expressivity for a breath of phenotypes, including neurodevelopmental defects such as strabismus, pituitary defects, intellectual impairment, as well as defects in heart and kidney. Here, we report two novel ROBO1 variants associated with very distinct phenotypes. A homozygous missense p.S1522L variant in three affected siblings with nystagmus; and a monoallelic de novo p.D422G variant in a proband who presented with early-onset epileptic encephalopathy. We modeled these variants in Drosophila and first generated a null allele by inserting a CRIMIC T2A-GAL4 in an intron. Flies that lack robo1 exhibit reduced viability but have very severe midline crossing defects in the central nervous system. The fly wild-type cDNA driven by T2A-Gal4 partially rescues both defects. Overexpression of the human reference ROBO1 with T2A-GAL4 is toxic and reduces viability, whereas the recessive p.S1522L variant is less toxic, suggesting that it is a partial loss-of-function allele. In contrast, the dominant variant in fly robo1 (p.D413G) affects protein localization, impairs axonal guidance activity and induces mild phototransduction defects, suggesting that it is a neomorphic allele. In summary, our studies expand the phenotypic spectrum associated with ROBO1 variant alleles.
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Affiliation(s)
- Yan Huang
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX 77030, USA
| | - Mengqi Ma
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX 77030, USA
| | - Xiao Mao
- National Health Commission Key Laboratory for Birth Defect Research and Prevention, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, Hunan 410008, China
- Department of Medical Genetics, Maternal and Child Health Hospital of Hunan Province, Changsha, Hunan 410008, China
| | - Davut Pehlivan
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Division of Neurology and Developmental Neuroscience, Department of Pediatrics, Baylor College of Medicine, Houston, TX 77030, USA
- Texas Children’s Hospital, Houston, TX 77030, USA
| | - Oguz Kanca
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX 77030, USA
| | - Feride Un-Candan
- Department of Neuroloy, Balikesir Ataturk Public Hospital, Balikesir 10100, Turkey
| | - Li Shu
- National Health Commission Key Laboratory for Birth Defect Research and Prevention, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, Hunan 410008, China
- Department of Medical Genetics, Maternal and Child Health Hospital of Hunan Province, Changsha, Hunan 410008, China
| | - Gulsen Akay
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Tadahiro Mitani
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Shenzhao Lu
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX 77030, USA
| | - Sukru Candan
- Department of Medical Genetics, Balikesir Ataturk Public Hospital, Balikesir 10100, Turkey
| | - Hua Wang
- National Health Commission Key Laboratory for Birth Defect Research and Prevention, Hunan Provincial Maternal and Child Health Care Hospital, Changsha, Hunan 410008, China
- Department of Medical Genetics, Maternal and Child Health Hospital of Hunan Province, Changsha, Hunan 410008, China
| | - Bo Xiao
- Neurology Department, Xiangya Hospital, Central South University, Changsha, Hunan 410008, China
| | - James R Lupski
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Texas Children’s Hospital, Houston, TX 77030, USA
| | - Hugo J Bellen
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
- Jan and Dan Duncan Neurological Research Institute, Texas Children’s Hospital, Baylor College of Medicine, Houston, TX 77030, USA
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9
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Boni N, Shapiro L, Honig B, Wu Y, Rubinstein R. On the formation of ordered protein assemblies in cell-cell interfaces. Proc Natl Acad Sci U S A 2022; 119:e2206175119. [PMID: 35969779 PMCID: PMC9407605 DOI: 10.1073/pnas.2206175119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 07/20/2022] [Indexed: 11/18/2022] Open
Abstract
Crystal structures of many cell-cell adhesion receptors reveal the formation of linear "molecular zippers" comprising an ordered one-dimensional array of proteins that form both intercellular (trans) and intracellular (cis) interactions. The clustered protocadherins (cPcdhs) provide an exemplar of this phenomenon and use it as a basis of barcoding of vertebrate neurons. Here, we report both Metropolis and kinetic Monte Carlo simulations of cPcdh zipper formation using simplified models of cPcdhs that nevertheless capture essential features of their three-dimensional structure. The simulations reveal that the formation of long zippers is an implicit feature of cPcdh structure and is driven by their cis and trans interactions that have been quantitatively characterized in previous work. Moreover, in agreement with cryo-electron tomography studies, the zippers are found to organize into two-dimensional arrays even in the absence of attractive interactions between individual zippers. Our results suggest that the formation of ordered two-dimensional arrays of linear zippers of adhesion proteins is a common feature of cell-cell interfaces. From the perspective of simulations, they demonstrate the importance of a realistic depiction of adhesion protein structure and interactions if important biological phenomena are to be properly captured.
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Affiliation(s)
- Nadir Boni
- School of Neurobiology, Biochemistry and Biophysics, Tel Aviv University, Tel Aviv-Yafo, Israel
| | - Lawrence Shapiro
- Zuckerman Mind, Brain and Behavior Institute, Columbia University, New York, NY 10027
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032
| | - Barry Honig
- Zuckerman Mind, Brain and Behavior Institute, Columbia University, New York, NY 10027
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032
- Department of Systems Biology, Columbia University, New York, NY 10032
- Department of Medicine, Division of Nephrology, Columbia University, New York, NY 10032
| | - Yinghao Wu
- Department of Systems and Computational Biology, Albert Einstein College of Medicine, Bronx, NY 10461
| | - Rotem Rubinstein
- School of Neurobiology, Biochemistry and Biophysics, Tel Aviv University, Tel Aviv-Yafo, Israel
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv-Yafo, Israel
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10
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Miyaguchi M, Nakanishi Y, Maturana AD, Mizutani K, Niimi T. Conformational Change of the Hairpin-like-structured Robo2 Ectodomain Allows NELL1/2 Binding. J Mol Biol 2022; 434:167777. [DOI: 10.1016/j.jmb.2022.167777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 07/29/2022] [Accepted: 08/02/2022] [Indexed: 10/16/2022]
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11
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Ahirwar DK, Peng B, Charan M, Misri S, Mishra S, Kaul K, Sassi S, Gadepalli VS, Siddiqui J, Miles WO, Ganju RK. Slit2/Robo1 signaling inhibits small-cell lung cancer by targeting β-catenin signaling in tumor cells and macrophages. Mol Oncol 2022; 17:839-856. [PMID: 35838343 PMCID: PMC10158774 DOI: 10.1002/1878-0261.13289] [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: 04/29/2022] [Revised: 06/16/2022] [Accepted: 07/13/2022] [Indexed: 01/11/2023] Open
Abstract
Small-cell lung cancer (SCLC) is an aggressive neuroendocrine subtype of lung cancer with poor patient prognosis. However, the mechanisms that regulate SCLC progression and metastasis remain undefined. Here, we show that the expression of the slit guidance ligand 2 (SLIT2) tumor suppressor gene is reduced in SCLC tumors relative to adjacent normal tissue. In addition, the expression of the SLIT2 receptor, roundabout guidance receptor 1 (ROBO1), is upregulated. We find a positive association between SLIT2 expression and the Yes1 associated transcriptional regulator (YAP1)-expressing SCLC subtype (SCLC-Y), which shows a better prognosis. Using genetically engineered SCLC cells, adenovirus gene therapy, and preclinical xenograft models, we show that SLIT2 overexpression or the deletion of ROBO1 restricts tumor growth in vitro and in vivo. Mechanistic studies revealed significant inhibition of myeloid-derived suppressor cells (MDSCs) and M2-like tumor-associated macrophages (TAMs) in the SCLC tumors. In addition, SLIT2 enhances M1-like and phagocytic macrophages. Molecular analysis showed that ROBO1 knockout or SLIT2 overexpression suppresses the transforming growth factor beta 1 (TGF-β1)/β-catenin signaling pathway in both tumor cells and macrophages. Overall, we find that SLIT2 and ROBO1 have contrasting effects on SCLC tumors. SLIT2 suppresses, whereas ROBO1 promotes, SCLC growth by regulating the Tgf-β1/glycogen synthase kinase-3 beta (GSK3)/β-catenin signaling pathway in tumor cells and TAMs. These studies indicate that SLIT2 could be used as a novel therapeutic agent against aggressive SCLC.
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Affiliation(s)
- Dinesh K Ahirwar
- Department of Pathology, College of Medicine, The Ohio State University, Columbus, OH, USA.,Comprehensive Cancer Center, The Ohio State University, Columbus, OH, USA.,Department of Bioscience & Bioengineering, Indian Institute of Technology, Jodhpur, India
| | - Bo Peng
- Department of Pathology, College of Medicine, The Ohio State University, Columbus, OH, USA
| | - Manish Charan
- Department of Pathology, College of Medicine, The Ohio State University, Columbus, OH, USA
| | - Swati Misri
- Department of Pathology, College of Medicine, The Ohio State University, Columbus, OH, USA
| | - Sanjay Mishra
- Department of Pathology, College of Medicine, The Ohio State University, Columbus, OH, USA
| | - Kirti Kaul
- Department of Pathology, College of Medicine, The Ohio State University, Columbus, OH, USA
| | - Salha Sassi
- Department of Pathology, College of Medicine, The Ohio State University, Columbus, OH, USA
| | | | - Jalal Siddiqui
- Comprehensive Cancer Center, The Ohio State University, Columbus, OH, USA.,Department of Cancer Biology and Genetics, The Ohio State University, Columbus, OH, USA
| | - Wayne O Miles
- Comprehensive Cancer Center, The Ohio State University, Columbus, OH, USA.,Department of Cancer Biology and Genetics, The Ohio State University, Columbus, OH, USA
| | - Ramesh K Ganju
- Department of Pathology, College of Medicine, The Ohio State University, Columbus, OH, USA.,Comprehensive Cancer Center, The Ohio State University, Columbus, OH, USA
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12
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Münch J, Engesser M, Schönauer R, Hamm JA, Hartig C, Hantmann E, Akay G, Pehlivan D, Mitani T, Coban Akdemir Z, Tüysüz B, Shirakawa T, Dateki S, Claus LR, van Eerde AM, Smol T, Devisme L, Franquet H, Attié-Bitach T, Wagner T, Bergmann C, Höhn AK, Shril S, Pollack A, Wenger T, Scott AA, Paolucci S, Buchan J, Gabriel GC, Posey JE, Lupski JR, Petit F, McCarthy AA, Pazour GJ, Lo CW, Popp B, Halbritter J. Biallelic pathogenic variants in roundabout guidance receptor 1 associate with syndromic congenital anomalies of the kidney and urinary tract. Kidney Int 2022; 101:1039-1053. [PMID: 35227688 PMCID: PMC10010616 DOI: 10.1016/j.kint.2022.01.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 11/30/2021] [Accepted: 01/11/2022] [Indexed: 11/16/2022]
Abstract
Congenital anomalies of the kidney and urinary tract (CAKUT) represent the most common cause of chronic kidney failure in children. Despite growing knowledge of the genetic causes of CAKUT, the majority of cases remain etiologically unsolved. Genetic alterations in roundabout guidance receptor 1 (ROBO1) have been associated with neuronal and cardiac developmental defects in living individuals. Although Slit-Robo signaling is pivotal for kidney development, diagnostic ROBO1 variants have not been reported in viable CAKUT to date. By next-generation-sequencing methods, we identified six unrelated individuals and two non-viable fetuses with biallelic truncating or combined missense and truncating variants in ROBO1. Kidney and genitourinary manifestation included unilateral or bilateral kidney agenesis, vesicoureteral junction obstruction, vesicoureteral reflux, posterior urethral valve, genital malformation, and increased kidney echogenicity. Further clinical characteristics were remarkably heterogeneous, including neurodevelopmental defects, intellectual impairment, cerebral malformations, eye anomalies, and cardiac defects. By in silico analysis, we determined the functional significance of identified missense variants and observed absence of kidney ROBO1 expression in both human and murine mutant tissues. While its expression in multiple tissues may explain heterogeneous organ involvement, variability of the kidney disease suggests gene dosage effects due to a combination of null alleles with mild hypomorphic alleles. Thus, comprehensive genetic analysis in CAKUT should include ROBO1 as a new cause of recessively inherited disease. Hence, in patients with already established ROBO1-associated cardiac or neuronal disorders, screening for kidney involvement is indicated.
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Affiliation(s)
- Johannes Münch
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, Berlin, Germany; Division of Nephrology, University of Leipzig Medical Center, Leipzig, Germany
| | - Marie Engesser
- Division of Nephrology, University of Leipzig Medical Center, Leipzig, Germany
| | - Ria Schönauer
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, Berlin, Germany; Division of Nephrology, University of Leipzig Medical Center, Leipzig, Germany
| | - J Austin Hamm
- East Tennessee Children's Hospital, Genetic Center, Knoxville, Tennessee, USA
| | - Christin Hartig
- Division of Nephrology, University of Leipzig Medical Center, Leipzig, Germany
| | - Elena Hantmann
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, Berlin, Germany; Division of Nephrology, University of Leipzig Medical Center, Leipzig, Germany
| | - Gulsen Akay
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA; Department of Pediatrics, University of Utah, Salt Lake, Utah, USA
| | - Davut Pehlivan
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA; Division of Neurology and Developmental Neuroscience, Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA; Texas Children's Hospital, Houston, Texas, USA
| | - Tadahiro Mitani
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - Zeynep Coban Akdemir
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA; Department of Epidemiology, Human Genetics, and Environmental Sciences, Human Genetics Center, School of Public Health, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Beyhan Tüysüz
- Department of Pediatric Genetics, Istanbul University Cerrahpasa Medical Faculty, Istanbul, Turkey
| | | | - Sumito Dateki
- Department of Pediatrics, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Laura R Claus
- Department of Genetics, University Medical Center Utrecht, Utrecht, the Netherlands
| | | | - Thomas Smol
- Centre Hospitalier Universitaire de Lille, Institut de Génétique Médicale, Lille, France
| | - Louise Devisme
- Centre Hospitalier Universitaire de Lille, Institut de Pathologie, Lille, France
| | - Hélène Franquet
- Centre Hospitalier Universitaire de Lille, Institut de Pathologie, Lille, France
| | - Tania Attié-Bitach
- Laboratoire de biologie médicale multisites SeqOIA, Paris, France; Service de Médecine Génomique des Maladies Rares, APHP.Centre, Université de Paris, Paris, France
| | - Timo Wagner
- Medizinische Genetik Mainz, Limbach Genetics, Mainz, Germany
| | - Carsten Bergmann
- Medizinische Genetik Mainz, Limbach Genetics, Mainz, Germany; Department of Medicine, Nephrology, University Hospital Freiburg, Freiburg, Germany
| | - Anne Kathrin Höhn
- Division of Pathology, University of Leipzig Medical Center, Leipzig, Germany
| | - Shirlee Shril
- Division of Nephrology, Boston Children's Hospital, Boston, USA
| | - Ari Pollack
- Division of Genetic Medicine, University of Washington, Seattle, Washington, USA
| | - Tara Wenger
- Division of Genetic Medicine, University of Washington, Seattle, Washington, USA
| | - Abbey A Scott
- Division of Genetic Medicine, Seattle Children's Hospital, Seattle, Washington, USA
| | - Sarah Paolucci
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington, USA
| | - Jillian Buchan
- Department of Laboratory Medicine and Pathology, University of Washington, Seattle, Washington, USA
| | - George C Gabriel
- Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Jennifer E Posey
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - James R Lupski
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA; Texas Children's Hospital, Houston, Texas, USA; Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA
| | - Florence Petit
- Centre Hospitalier Universitaire de Lille, Clinique de Génétique Guy Fontaine, Lille, France
| | | | - Gregory J Pazour
- Program in Molecular Medicine, University of Massachusetts Medical School, Biotech II, Worcester, USA
| | - Cecilia W Lo
- Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA.
| | - Bernt Popp
- Institute for Human Genetics, University of Leipzig Medical Center, Leipzig, Germany.
| | - Jan Halbritter
- Department of Nephrology and Medical Intensive Care, Charité-Universitätsmedizin Berlin, Berlin, Germany; Division of Nephrology, University of Leipzig Medical Center, Leipzig, Germany.
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13
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Zhou SL, Luo CB, Song CL, Zhou ZJ, Xin HY, Hu ZQ, Sun RQ, Fan J, Zhou J. Genomic evolution and the impact of SLIT2 mutation in relapsed intrahepatic cholangiocarcinoma. Hepatology 2022; 75:831-846. [PMID: 34543483 DOI: 10.1002/hep.32164] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 09/07/2021] [Accepted: 09/16/2021] [Indexed: 01/01/2023]
Abstract
BACKGROUND AND AIMS Intrahepatic cholangiocarcinoma (ICC) is aggressive and has high rates of relapse, conferring poor long-term survival after curative resection. Little is known about the genomic evolution that occurs during ICC relapse. APPROACH AND RESULTS We conducted whole-exome sequencing of 30 paired primary and relapsed tumors from 10 patients with ICC who received curative resection. We sought to identify frequently altered genes, infer tumor subclonal architectures, and track genomic evolution from primary to relapsed tumors. We examined functional effects and the mechanism of action of SLIT2, a gene specifically mutated in relapsed tumors, on tumor growth and metastasis and the tumor microenvironment. Our results indicated that relapsed ICCs were genetically derived from intrahepatic dissemination of primary tumors. However, they acquired additional mutations while maintaining most drivers, such as TP53 and IDH1. Multiregion sequencing suggested polyclonal seeding of ICC dissemination. Four of 10 relapsed ICCs acquired SLIT2 mutations that were not present in the corresponding primary tumors. Validation in an expanded sample revealed SLIT2 mutations in 2.3% (1/44) of primary ICCs and 29.5% (13/44) of relapsed ICCs. Biofunctional investigations revealed that inactivating mutation of SLIT2 resulted in activation of PI3K-Akt signaling in ICC cells, directly enhanced neutrophil chemotaxis, mediated tumor-associated neutrophil infiltration, and contributed to ICC growth and metastasis. CONCLUSIONS We characterized genomic evolution during ICC relapse and identified SLIT2 as a driver of tumor dissemination and tumor-associated neutrophil infiltration.
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Affiliation(s)
- Shao-Lai Zhou
- Department of Liver Surgery and TransplantationLiver Cancer InstituteZhongshan HospitalFudan UniversityShanghaiChina
| | - Chu-Bin Luo
- Department of Liver Surgery and TransplantationLiver Cancer InstituteZhongshan HospitalFudan UniversityShanghaiChina
| | - Cheng-Li Song
- Institute of Cancer Stem CellDalian Medical UniversityDalianLiaoningChina
| | - Zheng-Jun Zhou
- Department of Liver Surgery and TransplantationLiver Cancer InstituteZhongshan HospitalFudan UniversityShanghaiChina
| | - Hao-Yang Xin
- Department of Liver Surgery and TransplantationLiver Cancer InstituteZhongshan HospitalFudan UniversityShanghaiChina
| | - Zhi-Qiang Hu
- Department of Liver Surgery and TransplantationLiver Cancer InstituteZhongshan HospitalFudan UniversityShanghaiChina
| | - Rong-Qi Sun
- Department of Liver Surgery and TransplantationLiver Cancer InstituteZhongshan HospitalFudan UniversityShanghaiChina
| | - Jia Fan
- Department of Liver Surgery and TransplantationLiver Cancer InstituteZhongshan HospitalFudan UniversityShanghaiChina.,State Key Laboratory of Genetic EngineeringFudan UniversityShanghaiChina
| | - Jian Zhou
- Department of Liver Surgery and TransplantationLiver Cancer InstituteZhongshan HospitalFudan UniversityShanghaiChina.,State Key Laboratory of Genetic EngineeringFudan UniversityShanghaiChina
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14
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Blockus H, Rolotti SV, Szoboszlay M, Peze-Heidsieck E, Ming T, Schroeder A, Apostolo N, Vennekens KM, Katsamba PS, Bahna F, Mannepalli S, Ahlsen G, Honig B, Shapiro L, de Wit J, Losonczy A, Polleux F. Synaptogenic activity of the axon guidance molecule Robo2 underlies hippocampal circuit function. Cell Rep 2021; 37:109828. [PMID: 34686348 PMCID: PMC8605498 DOI: 10.1016/j.celrep.2021.109828] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 07/06/2021] [Accepted: 09/22/2021] [Indexed: 01/03/2023] Open
Abstract
Synaptic connectivity within adult circuits exhibits a remarkable degree of cellular and subcellular specificity. We report that the axon guidance receptor Robo2 plays a role in establishing synaptic specificity in hippocampal CA1. In vivo, Robo2 is present and required postsynaptically in CA1 pyramidal neurons (PNs) for the formation of excitatory (E) but not inhibitory (I) synapses, specifically in proximal but not distal dendritic compartments. In vitro approaches show that the synaptogenic activity of Robo2 involves a trans-synaptic interaction with presynaptic Neurexins, as well as binding to its canonical extracellular ligand Slit. In vivo 2-photon Ca2+ imaging of CA1 PNs during spatial navigation in awake behaving mice shows that preventing Robo2-dependent excitatory synapse formation cell autonomously during development alters place cell properties of adult CA1 PNs. Our results identify a trans-synaptic complex linking the establishment of synaptic specificity to circuit function.
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Affiliation(s)
- Heike Blockus
- Department of Neuroscience, Columbia University, New York, NY 10027, USA; Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA
| | - Sebi V Rolotti
- Department of Neuroscience, Columbia University, New York, NY 10027, USA; Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA
| | - Miklos Szoboszlay
- Department of Neuroscience, Columbia University, New York, NY 10027, USA; Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA
| | - Eugénie Peze-Heidsieck
- Department of Neuroscience, Columbia University, New York, NY 10027, USA; Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA
| | - Tiffany Ming
- Department of Neuroscience, Columbia University, New York, NY 10027, USA; Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA
| | - Anna Schroeder
- VIB Center for Brain and Disease Research, Herestraat 49, 3000 Leuven, Belgium; Department of Neurosciences, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Nuno Apostolo
- VIB Center for Brain and Disease Research, Herestraat 49, 3000 Leuven, Belgium; Department of Neurosciences, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Kristel M Vennekens
- VIB Center for Brain and Disease Research, Herestraat 49, 3000 Leuven, Belgium; Department of Neurosciences, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Phinikoula S Katsamba
- Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA
| | - Fabiana Bahna
- Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA
| | - Seetha Mannepalli
- Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA
| | - Goran Ahlsen
- Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA
| | - Barry Honig
- Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA; Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA; Department of Medicine, Columbia University, New York, NY 10032, USA
| | - Lawrence Shapiro
- Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA; Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY 10032, USA
| | - Joris de Wit
- VIB Center for Brain and Disease Research, Herestraat 49, 3000 Leuven, Belgium; Department of Neurosciences, KU Leuven, Herestraat 49, 3000 Leuven, Belgium
| | - Attila Losonczy
- Department of Neuroscience, Columbia University, New York, NY 10027, USA; Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA; Kavli Institute for Brain Science, Columbia University, New York, NY 10027, USA.
| | - Franck Polleux
- Department of Neuroscience, Columbia University, New York, NY 10027, USA; Zuckerman Mind Brain Behavior Institute, Columbia University, New York, NY 10027, USA; Kavli Institute for Brain Science, Columbia University, New York, NY 10027, USA.
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15
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Geraldo LH, Xu Y, Jacob L, Pibouin-Fragner L, Rao R, Maissa N, Verreault M, Lemaire N, Knosp C, Lesaffre C, Daubon T, Dejaegher J, Solie L, Rudewicz J, Viel T, Tavitian B, De Vleeschouwer S, Sanson M, Bikfalvi A, Idbaih A, Lu QR, Lima FR, Thomas JL, Eichmann A, Mathivet T. SLIT2/ROBO signaling in tumor-associated microglia and macrophages drives glioblastoma immunosuppression and vascular dysmorphia. J Clin Invest 2021; 131:141083. [PMID: 34181595 PMCID: PMC8363292 DOI: 10.1172/jci141083] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 06/22/2021] [Indexed: 12/27/2022] Open
Abstract
SLIT2 is a secreted polypeptide that guides migration of cells expressing Roundabout 1 and 2 (ROBO1 and ROBO2) receptors. Herein, we investigated SLIT2/ROBO signaling effects in gliomas. In patients with glioblastoma (GBM), SLIT2 expression increased with malignant progression and correlated with poor survival and immunosuppression. Knockdown of SLIT2 in mouse glioma cells and patient-derived GBM xenografts reduced tumor growth and rendered tumors sensitive to immunotherapy. Tumor cell SLIT2 knockdown inhibited macrophage invasion and promoted a cytotoxic gene expression profile, which improved tumor vessel function and enhanced efficacy of chemotherapy and immunotherapy. Mechanistically, SLIT2 promoted microglia/macrophage chemotaxis and tumor-supportive polarization via ROBO1- and ROBO2-mediated PI3K-γ activation. Macrophage Robo1 and Robo2 deletion and systemic SLIT2 trap delivery mimicked SLIT2 knockdown effects on tumor growth and the tumor microenvironment (TME), revealing SLIT2 signaling through macrophage ROBOs as a potentially novel regulator of the GBM microenvironment and immunotherapeutic target for brain tumors.
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Affiliation(s)
- Luiz H. Geraldo
- Université de Paris, Paris Cardiovascular Research Center, INSERM, Paris, France
- Biomedical Sciences Institute, Federal University of Rio de Janeiro, Brazil
| | - Yunling Xu
- Université de Paris, Paris Cardiovascular Research Center, INSERM, Paris, France
| | - Laurent Jacob
- Université de Paris, Paris Cardiovascular Research Center, INSERM, Paris, France
| | | | - Rohit Rao
- Brain Tumor Center, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, USA
| | - Nawal Maissa
- Université de Paris, Paris Cardiovascular Research Center, INSERM, Paris, France
| | - Maïté Verreault
- Sorbonne Université, INSERM U1127, CNRS UMR 7225, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière-Charles Foix, Service de Neurologie 2-Mazarin, Paris, France
| | - Nolwenn Lemaire
- Sorbonne Université, INSERM U1127, CNRS UMR 7225, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière-Charles Foix, Service de Neurologie 2-Mazarin, Paris, France
| | - Camille Knosp
- Université de Paris, Paris Cardiovascular Research Center, INSERM, Paris, France
| | - Corinne Lesaffre
- Université de Paris, Paris Cardiovascular Research Center, INSERM, Paris, France
| | | | - Joost Dejaegher
- Department of Neurosciences and
- Department of Neurosurgery, UZ Leuven, Leuven, Belgium
| | - Lien Solie
- Department of Neurosciences and
- Department of Neurosurgery, UZ Leuven, Leuven, Belgium
| | | | - Thomas Viel
- Université de Paris, Paris Cardiovascular Research Center, INSERM, Paris, France
| | - Bertrand Tavitian
- Université de Paris, Paris Cardiovascular Research Center, INSERM, Paris, France
| | | | - Marc Sanson
- Sorbonne Université, INSERM U1127, CNRS UMR 7225, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière-Charles Foix, Service de Neurologie 2-Mazarin, Paris, France
- Onconeurotek Tumor Bank, Institut du Cerveau et de la Moelle épinière-ICM, Paris, France
| | | | - Ahmed Idbaih
- Sorbonne Université, INSERM U1127, CNRS UMR 7225, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière-Charles Foix, Service de Neurologie 2-Mazarin, Paris, France
| | - Q. Richard Lu
- Brain Tumor Center, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, USA
| | - Flavia R.S. Lima
- Biomedical Sciences Institute, Federal University of Rio de Janeiro, Brazil
| | - Jean-Leon Thomas
- Sorbonne Université, INSERM U1127, CNRS UMR 7225, Institut du Cerveau, ICM, AP-HP, Hôpitaux Universitaires La Pitié Salpêtrière-Charles Foix, Service de Neurologie 2-Mazarin, Paris, France
- Department of Neurology
| | - Anne Eichmann
- Université de Paris, Paris Cardiovascular Research Center, INSERM, Paris, France
- Cardiovascular Research Center, Department of Internal Medicine, and
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, Connecticut, USA
| | - Thomas Mathivet
- Université de Paris, Paris Cardiovascular Research Center, INSERM, Paris, France
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16
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Klein R, Pasterkamp RJ. Recent advances in inter-cellular interactions during neural circuit assembly. Curr Opin Neurobiol 2021; 69:25-32. [PMID: 33383489 DOI: 10.1016/j.conb.2020.12.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Revised: 12/02/2020] [Accepted: 12/07/2020] [Indexed: 12/12/2022]
Abstract
Neural circuit assembly is regulated by inter-cellular interactions involving secreted and surface-tethered guidance molecules. Here, we review recent progress in our understanding of their mechanisms-of-action and biological effects. We discuss mechanisms through which the secreted cue Netrin-1 regulates neuron migration and highlight novel roles for axon-derived secreted guidance cues. We cover recent structural work at atomic resolution that provides new insights into the activation mechanisms of axon guidance receptors and into protein complexes containing cell adhesion molecules, such as Teneurin (Ten), Latrophilin (Lphn) and FLRT. Ten-Ten homophilic, Ten-Lphn heterophilic, and Ten-Lphn-FLRT tripartite complexes seem to elicit distinct context-dependent cellular responses. Seemingly opposite responses can also be triggered by the Eph/ephrin signaling system. Here, recent work provides a simple mechanism for the decision of forming a new synapse versus rejection of the pre-synaptic partner. These studies identify novel regulatory mechanisms and biological functions that will apply generally in developing neural systems.
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Affiliation(s)
- Rüdiger Klein
- Department Molecules-Signaling-Development, Max Planck Institute of Neurobiology, Am Klopferspitz 18, 82152 Martinsried, Germany.
| | - Ronald Jeroen Pasterkamp
- Department of Translational Neuroscience, University Medical Center (UMC) Utrecht Brain Center, Utrecht University, Universiteitsweg 100, 3584 CG, Utrecht, The Netherlands.
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17
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Qu Z, Zhang A, Yan D. Robo functions as an attractive cue for glial migration through SYG-1/Neph. eLife 2020; 9:e57921. [PMID: 33211005 PMCID: PMC7676865 DOI: 10.7554/elife.57921] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 11/02/2020] [Indexed: 01/06/2023] Open
Abstract
As one of the most-studied receptors, Robo plays functions in many biological processes, and its functions highly depend on Slit, the ligand of Robo. Here we uncover a Slit-independent role of Robo in glial migration and show that neurons can release an extracellular fragment of Robo upon cleavage to attract glia during migration in Caenorhabditis elegans. Furthermore, we identified the conserved cell adhesion molecule SYG-1/Neph as a receptor for the cleaved extracellular Robo fragment to mediate glial migration and SYG-1/Neph functions through regulation of the WAVE complex. Our studies reveal a previously unknown Slit-independent function and regulatory mechanism of Robo and show that the cleaved extracellular fragment of Robo can function as a ligand for SYG-1/Neph to guide glial migration. As Robo, the cleaved region of Robo, and SYG-1/Neph are all highly conserved across the animal kingdom, our findings may present a conserved Slit-independent Robo mechanism during brain development.
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Affiliation(s)
- Zhongwei Qu
- Department of Molecular Genetics and Microbiology, Duke University Medical CenterDurhamUnited States
| | - Albert Zhang
- Department of Molecular Genetics and Microbiology, Duke University Medical CenterDurhamUnited States
| | - Dong Yan
- Department of Molecular Genetics and Microbiology, Duke University Medical CenterDurhamUnited States
- Department of Neurobiology, Regeneration Next Initiative, Duke Center for Neurodegeneration and Neurotherapeutics, and Duke Institute for Brain Sciences, Duke University Medical CenterDurhamUnited States
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18
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Brown HE, Evans TA. Minimal structural elements required for midline repulsive signaling and regulation of Drosophila Robo1. PLoS One 2020; 15:e0241150. [PMID: 33091076 PMCID: PMC7580999 DOI: 10.1371/journal.pone.0241150] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Accepted: 10/08/2020] [Indexed: 02/07/2023] Open
Abstract
The Roundabout (Robo) family of axon guidance receptors has a conserved ectodomain arrangement of five immunoglobulin-like (Ig) domains plus three fibronectin type III (Fn) repeats. Based on the strong evolutionary conservation of this domain structure among Robo receptors, as well as in vitro structural and domain-domain interaction studies of Robo family members, this ectodomain arrangement is predicted to be important for Robo receptor signaling in response to Slit ligands. Here, we define the minimal ectodomain structure required for Slit binding and midline repulsive signaling in vivo by Drosophila Robo1. We find that the majority of the Robo1 ectodomain is dispensable for both Slit binding and repulsive signaling. We show that a significant level of midline repulsive signaling activity is retained when all Robo1 ectodomain elements apart from Ig1 are deleted, and that the combination of Ig1 plus one additional ectodomain element (Ig2, Ig5, or Fn3) is sufficient to restore midline repulsion to wild type levels. Further, we find that deleting four out of five Robo1 Ig domains (ΔIg2-5) does not affect negative regulation of Robo1 by Commissureless (Comm) or Robo2, while variants lacking all three fibronectin repeats (ΔFn1-3 and ΔIg2-Fn3) are insensitive to regulation by both Comm and Robo2, signifying a novel regulatory role for Robo1's Fn repeats. Our results provide an in vivo perspective on the importance of the conserved 5+3 ectodomain structure of Robo receptors, and suggest that specific biochemical properties and/or ectodomain structural conformations observed in vitro for domains other than Ig1 may have limited significance for in vivo signaling in the context of midline repulsion.
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Affiliation(s)
- Haley E. Brown
- Department of Biological Sciences, University of Arkansas, Fayetteville, Arkansas, United States of America
| | - Timothy A. Evans
- Department of Biological Sciences, University of Arkansas, Fayetteville, Arkansas, United States of America
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19
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Gorla M, Bashaw GJ. Molecular mechanisms regulating axon responsiveness at the midline. Dev Biol 2020; 466:12-21. [PMID: 32818516 DOI: 10.1016/j.ydbio.2020.08.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 08/12/2020] [Accepted: 08/12/2020] [Indexed: 02/06/2023]
Abstract
During embryonic development in bilaterally symmetric organisms, correct midline crossing is important for the proper formation of functional neural circuits. The aberrant development of neural circuits can result in multiple neurodevelopmental disorders, including horizontal gaze palsy, congenital mirror movement disorder, and autism spectrum disorder. Thus, understanding the molecular mechanisms that regulate proper axon guidance at the midline can provide insights into the pathology of neurological disorders. The signaling mechanisms that regulate midline crossing have been extensively studied in the Drosophila ventral nerve cord and the mouse embryonic spinal cord. In this review, we discuss these axon guidance mechanisms, highlighting the most recent advances in the understanding of how commissural axons switch their responsiveness from attractants to repellents during midline crossing.
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Affiliation(s)
- Madhavi Gorla
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Greg J Bashaw
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
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20
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Chataigner LMP, Leloup N, Janssen BJC. Structural Perspectives on Extracellular Recognition and Conformational Changes of Several Type-I Transmembrane Receptors. Front Mol Biosci 2020; 7:129. [PMID: 32850948 PMCID: PMC7427315 DOI: 10.3389/fmolb.2020.00129] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 06/02/2020] [Indexed: 12/19/2022] Open
Abstract
Type-I transmembrane proteins represent a large group of 1,412 proteins in humans with a multitude of functions in cells and tissues. They are characterized by an extracellular, or luminal, N-terminus followed by a single transmembrane helix and a cytosolic C-terminus. The domain composition and structures of the extracellular and intercellular segments differ substantially amongst its members. Most of the type-I transmembrane proteins have roles in cell signaling processes, as ligands or receptors, and in cellular adhesion. The extracellular segment often determines specificity and can control signaling and adhesion. Here we focus on recent structural understanding on how the extracellular segments of several diverse type-I transmembrane proteins engage in interactions and can undergo conformational changes for their function. Interactions at the extracellular side by proteins on the same cell or between cells are enhanced by the transmembrane setting. Extracellular conformational domain rearrangement and structural changes within domains alter the properties of the proteins and are used to regulate signaling events. The combination of structural properties and interactions can support the formation of larger-order assemblies on the membrane surface that are important for cellular adhesion and intercellular signaling.
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Affiliation(s)
- Lucas M P Chataigner
- Crystal and Structural Chemistry, Bijvoet Center for Biomolecular Research, Faculty of Science, Utrecht University, Utrecht, Netherlands
| | - Nadia Leloup
- Structural Biology and Protein Biochemistry, Morphic Therapeutic, Waltham, MA, United States
| | - Bert J C Janssen
- Crystal and Structural Chemistry, Bijvoet Center for Biomolecular Research, Faculty of Science, Utrecht University, Utrecht, Netherlands
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Sherchan P, Travis ZD, Tang J, Zhang JH. The potential of Slit2 as a therapeutic target for central nervous system disorders. Expert Opin Ther Targets 2020; 24:805-818. [PMID: 32378435 PMCID: PMC7529836 DOI: 10.1080/14728222.2020.1766445] [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: 01/22/2020] [Accepted: 05/05/2020] [Indexed: 10/24/2022]
Abstract
Introduction: Slit2 is an extracellular matrix protein that regulates migration of developing axons during central nervous system (CNS) development. Roundabout (Robo) receptors expressed by various cell types in the CNS, mediate intracellular signal transduction pathways for Slit2. Recent studies indicate that Slit2 plays important protective roles in a myriad of processes such as cell migration, immune response, vascular permeability, and angiogenesis in CNS pathologies. Areas covered: This review provides an overview of the diverse functions of Slit2 in CNS disorders and discusses the potential of Slit2 as a therapeutic target. We reviewed preclinical studies reporting the role of Slit2 in various CNS disease models, transgenic animal research, and rodent models that utilized Slit2 as a therapy. Expert opinion: Slit2 exerts a wide array of beneficial effects ranging from anti-migration, blood-brain barrier (BBB) protection, inhibition of peripheral immune cell infiltration, and anti-apoptosis in various disease models. However, a dual role of Slit2 in endothelial permeability has been observed in transgenic animals. Further research on Slit2 will be crucial including key issues such as effects of transgenic overexpression versus exogenous Slit2, function of Slit2 dependent on cellular expression of Robo receptors and the underlying pathology for potential clinical translation.
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Affiliation(s)
- Prativa Sherchan
- Center for Neuroscience Research, Department of Physiology and Pharmacology, Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA 92354, USA
| | - Zachary D. Travis
- Department of Earth and Biological Sciences, School of Medicine, Loma Linda University, Loma Linda, CA, 92354, USA and Center for Neuroscience Research, Loma Linda University School of Medicine, Loma Linda, CA, 92354, USA
- Department of Physiology and Pharmacology, Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA 92354, USA
| | - Jiping Tang
- Department of Physiology and Pharmacology, Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA 92354, USA
| | - John H. Zhang
- Center for Neuroscience Research, Department of Physiology and Pharmacology, Basic Sciences, Loma Linda University School of Medicine, Loma Linda, CA 92354, USA
- Departments of Anesthesiology, Neurosurgery and Neurology, Loma Linda University School of Medicine, Loma Linda, CA 92354, USA
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Rozbesky D, Monistrol J, Jain V, Hillier J, Padilla-Parra S, Jones EY. Drosophila OTK Is a Glycosaminoglycan-Binding Protein with High Conformational Flexibility. Structure 2020; 28:507-515.e5. [PMID: 32187531 PMCID: PMC7203548 DOI: 10.1016/j.str.2020.02.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 01/29/2020] [Accepted: 02/27/2020] [Indexed: 11/25/2022]
Abstract
The transmembrane protein OTK plays an essential role in plexin and Wnt signaling during Drosophila development. We have determined a crystal structure of the last three domains of the OTK ectodomain and found that OTK shows high conformational flexibility resulting from mobility at the interdomain interfaces. We failed to detect direct binding between Drosophila Plexin A (PlexA) and OTK, which was suggested previously. We found that, instead of PlexA, OTK directly binds semaphorin 1a. Our binding analyses further revealed that glycosaminoglycans, heparin and heparan sulfate, are ligands for OTK and thus may play a role in the Sema1a-PlexA axon guidance system.
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Affiliation(s)
- Daniel Rozbesky
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK.
| | - Jim Monistrol
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Vitul Jain
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - James Hillier
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Sergi Padilla-Parra
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; Cellular imaging, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; Department of Infectious Diseases, King's College London, Faculty of Life Sciences & Medicine, London SE1 9RT, UK; Randall Centre for Cell and Molecular Biology, King's College London, London SE1 1UL, UK
| | - E Yvonne Jones
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK.
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Rozbesky D, Jones EY. Cell guidance ligands, receptors and complexes - orchestrating signalling in time and space. Curr Opin Struct Biol 2020; 61:79-85. [PMID: 31862615 PMCID: PMC7171467 DOI: 10.1016/j.sbi.2019.11.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 11/15/2019] [Indexed: 01/28/2023]
Abstract
Members of four cell guidance molecule families (the netrins, slits, ephrins and semaphorins) interact with their cognate cell surface receptors to guide cells during development and maintain tissue homeostasis. Integrated structure and cell-based analyses are providing insight into the mechanisms by which these signalling systems can deliver myriad outcomes that require exquisite accuracy in timing and location. Here we review recent advances in our understanding of the roles of oligomeric states, auto-inhibition, signalling assembly size and composition in cell guidance cue function.
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Affiliation(s)
- Daniel Rozbesky
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, United Kingdom
| | - Edith Yvonne Jones
- Division of Structural Biology, Wellcome Centre for Human Genetics, University of Oxford, Oxford, OX3 7BN, United Kingdom.
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Pak JS, DeLoughery ZJ, Wang J, Acharya N, Park Y, Jaworski A, Özkan E. NELL2-Robo3 complex structure reveals mechanisms of receptor activation for axon guidance. Nat Commun 2020; 11:1489. [PMID: 32198364 PMCID: PMC7083938 DOI: 10.1038/s41467-020-15211-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Accepted: 02/24/2020] [Indexed: 11/24/2022] Open
Abstract
Axon pathfinding is critical for nervous system development, and it is orchestrated by molecular cues that activate receptors on the axonal growth cone. Robo family receptors bind Slit guidance cues to mediate axon repulsion. In mammals, the divergent family member Robo3 does not bind Slits, but instead signals axon repulsion from its own ligand, NELL2. Conversely, canonical Robos do not mediate NELL2 signaling. Here, we present the structures of NELL-Robo3 complexes, identifying a mode of ligand engagement for Robos that is orthogonal to Slit binding. We elucidate the structural basis for differential binding between NELL and Robo family members and show that NELL2 repulsive activity is a function of its Robo3 affinity and is enhanced by ligand trimerization. Our results reveal a mechanism of oligomerization-induced Robo activation for axon guidance and shed light on Robo family member ligand binding specificity, conformational variability, divergent modes of signaling, and evolution.
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Affiliation(s)
- Joseph S Pak
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, 60637, USA
- Grossman Institute for Neuroscience, Quantitative Biology and Human Behavior, University of Chicago, Chicago, IL, 60637, USA
| | - Zachary J DeLoughery
- Department of Neuroscience, Division of Biology and Medicine, Brown University, Providence, RI, 02912, USA
- Robert J. and Nancy D. Carney Institute for Brain Science, Providence, RI, 02912, USA
| | - Jing Wang
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, 60637, USA
- Grossman Institute for Neuroscience, Quantitative Biology and Human Behavior, University of Chicago, Chicago, IL, 60637, USA
| | - Nischal Acharya
- Department of Neuroscience, Division of Biology and Medicine, Brown University, Providence, RI, 02912, USA
- Robert J. and Nancy D. Carney Institute for Brain Science, Providence, RI, 02912, USA
| | - Yeonwoo Park
- Department of Human Genetics, University of Chicago, Chicago, IL, 60637, USA
| | - Alexander Jaworski
- Department of Neuroscience, Division of Biology and Medicine, Brown University, Providence, RI, 02912, USA.
- Robert J. and Nancy D. Carney Institute for Brain Science, Providence, RI, 02912, USA.
| | - Engin Özkan
- Department of Biochemistry and Molecular Biology, University of Chicago, Chicago, IL, 60637, USA.
- Grossman Institute for Neuroscience, Quantitative Biology and Human Behavior, University of Chicago, Chicago, IL, 60637, USA.
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Niimi T. Roles of Slit Ligands and Their Roundabout (Robo) Family of Receptors in Bone Remodeling. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 21:143-154. [PMID: 32986130 DOI: 10.1007/5584_2020_586] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Slit guidance ligands (Slits) and their roundabout (Robo) family of receptors are well-known axon guidance molecules that were originally identified in Drosophila mutants with commissural axon pathfinding defects. However, Slit-Robo signaling has been shown to be involved in not only neurogenesis, but also the development of other organs such as the kidney and heart. Recently, it was also revealed that Slit-Robo signaling plays an important role in bone metabolism. For example, osteoclast-derived Slit3 plays an osteoprotective role by synchronously stimulating bone formation by osteoblasts and suppressing bone resorption by osteoclasts through Robo receptors expressed on osteoblastic and osteoclastic cell lineages, making it a potential therapeutic target for metabolic bone disorders. Furthermore, osteoblast-derived Slit3 promotes bone formation indirectly as a proangiogenic factor. This review summarizes the recent progress on defining the roles of the Slit-Robo signaling in bone metabolism, and discusses the possible roles of the interaction between Robo and neural epidermal growth factor-like (NEL)-like (NELL) proteins that are novel ligands for Robo receptors.
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Affiliation(s)
- Tomoaki Niimi
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan.
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Lin YZ, Zhong XN, Chen X, Liang Y, Zhang H, Zhu DL. Roundabout signaling pathway involved in the pathogenesis of COPD by integrative bioinformatics analysis. Int J Chron Obstruct Pulmon Dis 2019; 14:2145-2162. [PMID: 31571851 PMCID: PMC6756575 DOI: 10.2147/copd.s216050] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Accepted: 08/22/2019] [Indexed: 01/11/2023] Open
Abstract
Purpose To explore the potential mechanism underpinning the development of chronic obstructive pulmonary disease (COPD) and to investigate the role of the Roundabout signaling pathway in COPD. Methods Three microarray datasets (GSE1650, GSE38974 and GSE76925) including 139 cases of severe COPD and 52 cases of normal smokers without carcinoma, were integrated to screen differentially expressed genes (DEGs) using bioinformatics methods. Gene ontology (GO) annotations and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway of the DEGs were performed by a DAVID online tool. Finally, a cigarette smoke (CS)- induced emphysema mice model was established, the lung mRNA expression levels of genes associated with Slit guidance ligand 2 (SLIT2) -Roundabout (ROBO) signaling pathway were detected by reverse transcription quantitative polymerase chain reaction (RT-qPCR), and the protein level of SLIT2 was examined by immunohistochemistry staining. Results A total of 315 DEGs were identified in three databases. GO and KEGG pathway analyses suggested that the inflammatory response, extracellular matrix disassembly, immune response, the apoptotic signaling pathway, ubiquitination and the Roundabout signaling pathway all together were involved in the development of COPD. The genes SLIT2 and ROBO2 were decreased in patients with COPD and these decreases were significantly negatively correlated with the disease stages of COPD. Consistently, the mRNA expression levels of SLIT2, ROBO1 and ROBO2, and the protein level of SLIT2 were revealed to be lower in the lungs of CS-induced emphysema mice compared with the air-exposed control mice. In addition, the SLIT2 protein level was negatively associated with alveolar mean linear intercept. Conclusion Integrated bioinformatics analysis may provide novel insights into the complicated pathogenesis of COPD, and to the best of our knowledge, this study is the first to provide evidence to suggest that the Roundabout signaling pathway may be involved in the pathogenesis of COPD.
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Affiliation(s)
- Yuan-Zhen Lin
- Department of Respiratory Medicine, The First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi, People's Republic of China
| | - Xiao-Ning Zhong
- Department of Respiratory Medicine, The First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi, People's Republic of China
| | - Xin Chen
- Department of Respiratory Medicine, The First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi, People's Republic of China
| | - Yi Liang
- Department of Respiratory Medicine, The First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi, People's Republic of China
| | - Hui Zhang
- Department of Respiratory Medicine, The First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi, People's Republic of China
| | - Dong-Lan Zhu
- Department of Respiratory Medicine, The First Affiliated Hospital, Guangxi Medical University, Nanning, Guangxi, People's Republic of China
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Abstract
The creation of complex neuronal networks relies on ligand-receptor interactions that mediate attraction or repulsion towards specific targets. Roundabouts comprise a family of single-pass transmembrane receptors facilitating this process upon interaction with the soluble extracellular ligand Slit protein family emanating from the midline. Due to the complexity and flexible nature of Robo receptors , their overall structure has remained elusive until now. Recent structural studies of the Robo 1 and Robo 2 ectodomains have provided the basis for a better understanding of their signalling mechanism. These structures reveal how Robo receptors adopt an auto-inhibited conformation on the cell surface that can be further stabilised by cis and/or trans oligmerisation arrays. Upon Slit -N binding Robo receptors must undergo a conformational change for Ig4 mediated dimerisation and signaling, probably via endocytosis. Furthermore, it's become clear that Robo receptors do not only act alone, but as large and more complex cell surface receptor assemblies to manifest directional and growth effects in a concerted fashion. These context dependent assemblies provide a mechanism to fine tune attractive and repulsive signals in a combinatorial manner required during neuronal development. While a mechanistic understanding of Slit mediated Robo signaling has advanced significantly further structural studies on larger assemblies are required for the design of new experiments to elucidate their role in cell surface receptor complexes. These will be necessary to understand the role of Slit -Robo signaling in neurogenesis, angiogenesis, organ development and cancer progression. In this chapter, we provide a review of the current knowledge in the field with a particular focus on the Roundabout receptor family.
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Affiliation(s)
- Francesco Bisiak
- European Molecular Biology Laboratory, Grenoble Outstation, 71 Avenue Des Martyrs, 38042, Grenoble, France.
| | - Andrew A McCarthy
- European Molecular Biology Laboratory, Grenoble Outstation, 71 Avenue Des Martyrs, 38042, Grenoble, France.
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