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Yurchenco PD, Kulczyk AW. Polymerizing laminins in development, health, and disease. J Biol Chem 2024; 300:107429. [PMID: 38825010 PMCID: PMC11260871 DOI: 10.1016/j.jbc.2024.107429] [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: 01/11/2024] [Revised: 05/12/2024] [Accepted: 05/26/2024] [Indexed: 06/04/2024] Open
Abstract
Polymerizing laminins are multi-domain basement membrane (BM) glycoproteins that self-assemble into cell-anchored planar lattices to establish the initial BM scaffold. Nidogens, collagen-IV and proteoglycans then bind to the scaffold at different domain loci to create a mature BM. The LN domains of adjacent laminins bind to each other to form a polymer node, while the LG domains attach to cytoskeletal-anchoring integrins and dystroglycan, as well as to sulfatides and heparan sulfates. The polymer node, the repeating unit of the polymer scaffold, is organized into a near-symmetrical triskelion. The structure, recently solved by cryo-electron microscopy in combination with AlphaFold2 modeling and biochemical studies, reveals how the LN surface residues interact with each other and how mutations cause failures of self-assembly in an emerging group of diseases, the LN-lamininopathies, that include LAMA2-related dystrophy and Pierson syndrome.
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Affiliation(s)
- Peter D Yurchenco
- Department of Pathology & Laboratory Medicine, Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey, USA.
| | - Arkadiusz W Kulczyk
- Department of Biochemistry and Microbiology, Institute for Quantitative Biomedicine, Rutgers University, Piscataway, New Jersey, USA
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2
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Bamberger C, Pankow S, Martínez-Bartolomé S, Diedrich JK, Park RSK, Yates JR. Analysis of the Tropism of SARS-CoV-2 Based on the Host Interactome of the Spike Protein. J Proteome Res 2023; 22:3742-3753. [PMID: 37939376 DOI: 10.1021/acs.jproteome.3c00387] [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: 11/10/2023]
Abstract
The β-coronavirus SARS-CoV-2 causes severe acute respiratory syndrome (COVID-19) in humans. It enters and infects epithelial airway cells upon binding of the receptor binding domain (RBD) of the virus entry protein spike to the host receptor protein Angiotensin Converting Enzyme 2 (ACE2). Here, we used coimmunoprecipitation coupled with bottom-up mass spectrometry to identify host proteins that engaged with the spike protein in human bronchial epithelial cells (16HBEo-). We found that the spike protein bound to extracellular laminin and thrombospondin and endoplasmatic reticulum (ER)-resident DJB11 and FBX2 proteins. The ER-resident proteins UGGT1, CALX, HSP7A, and GRP78/BiP bound preferentially to the original Wuhan D614 over the mutated G614 spike protein in the more rapidly spreading Alpha SARS-CoV-2 strain. The increase in protein binding to the D614 spike might be explained by higher accessibility of cryptic sites in "RDB open" and "S2 only" D614 spike protein conformations and may enable SARS-CoV-2 to infect additional, ACE2-negative cell types. Moreover, a novel proteome-based cell type set enrichment analysis (pCtSEA) found that host factors like laminin might render additional cell types such as macrophages and epithelial cells in the nephron permissive to SARS-CoV-2 infection.
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Affiliation(s)
- Casimir Bamberger
- Department of Molecular Medicine, The Scripps Research Institute 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Sandra Pankow
- Department of Molecular Medicine, The Scripps Research Institute 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Salvador Martínez-Bartolomé
- Department of Molecular Medicine, The Scripps Research Institute 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Jolene K Diedrich
- Department of Molecular Medicine, The Scripps Research Institute 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Robin S K Park
- Department of Molecular Medicine, The Scripps Research Institute 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - John R Yates
- Department of Molecular Medicine, The Scripps Research Institute 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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3
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Saiki R, Katayama K, Dohi K. Recent Advances in Proteinuric Kidney Disease/Nephrotic Syndrome: Lessons from Knockout/Transgenic Mouse Models. Biomedicines 2023; 11:1803. [PMID: 37509442 PMCID: PMC10376620 DOI: 10.3390/biomedicines11071803] [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: 05/17/2023] [Revised: 06/21/2023] [Accepted: 06/21/2023] [Indexed: 07/30/2023] Open
Abstract
Proteinuria is known to be associated with all-cause and cardiovascular mortality, and nephrotic syndrome is defined by the level of proteinuria and hypoalbuminemia. With advances in medicine, new causative genes for genetic kidney diseases are being discovered increasingly frequently. We reviewed articles on proteinuria/nephrotic syndrome, focal segmental glomerulosclerosis, membranous nephropathy, diabetic kidney disease/nephropathy, hypertension/nephrosclerosis, Alport syndrome, and rare diseases, which have been studied in mouse models. Significant progress has been made in understanding the genetics and pathophysiology of kidney diseases thanks to advances in science, but research in this area is ongoing. In the future, genetic analyses of patients with proteinuric kidney disease/nephrotic syndrome may ultimately lead to personalized treatment options.
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Affiliation(s)
- Ryosuke Saiki
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Tsu 514-8507, Japan
| | - Kan Katayama
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Tsu 514-8507, Japan
| | - Kaoru Dohi
- Department of Cardiology and Nephrology, Mie University Graduate School of Medicine, Tsu 514-8507, Japan
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Ruan J, McKee KK, Yurchenco PD, Yao Y. Exogenous laminin exhibits a unique vascular pattern in the brain via binding to dystroglycan and integrins. Fluids Barriers CNS 2022; 19:97. [PMID: 36463265 PMCID: PMC9719645 DOI: 10.1186/s12987-022-00396-y] [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: 08/16/2022] [Accepted: 11/28/2022] [Indexed: 12/07/2022] Open
Abstract
BACKGROUND Unlike other proteins that exhibit a diffusion pattern after intracerebral injection, laminin displays a vascular pattern. It remains unclear if this unique vascular pattern is caused by laminin-receptor interaction or laminin self-assembly. METHODS We compared the distribution of various wild-type laminin isoforms in the brain after intracerebral injection. To determine what causes the unique vascular pattern of laminin in the brain, laminin mutants with impaired receptor-binding and/or self-assembly activities and function-blocking antibodies to laminin receptors were used. In addition, the dynamics of laminin distribution and elimination were examined at multiple time points after intracerebral injection. RESULTS We found that β2-containing laminins had higher affinity for the vessels compared to β1-containing laminins. In addition, laminin mutants lacking receptor-binding domains but not that lacking self-assembly capability showed substantially reduced vascular pattern. Consistent with this finding, dystroglycan (DAG1) function-blocking antibody significantly reduced the vascular pattern of wild-type laminin-111. Although failed to affect the vascular pattern when used alone, integrin-β1 function-blocking antibody further decreased the vascular pattern when combined with DAG1 antibody. EDTA, which impaired laminini-DAG1 interaction by chelating Ca2+, also attenuated the vascular pattern. Immunohistochemistry revealed that laminins were predominantly located in the perivascular space in capillaries and venules/veins but not arterioles/arteries. The time-course study showed that laminin mutants with impaired receptor-engaging activity were more efficiently eliminated from the brain compared to their wild-type counterparts. Concordantly, significantly higher levels of mutant laminins were detected in the cerebral-spinal fluid (CSF). CONCLUSIONS These findings suggest that intracerebrally injected laminins are enriched in the perivascular space in a receptor (DAG1/integrin)-dependent rather than self-assembly-dependent manner and eliminated from the brain mainly via the perivascular clearance system.
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Affiliation(s)
- Jingsong Ruan
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd., MDC 8, Tampa, FL, 33612, USA
| | - Karen K McKee
- Department of Pathology and Laboratory Medicine, Rutgers University-Robert W. Johnson Medical School, Piscataway, NJ, USA
| | - Peter D Yurchenco
- Department of Pathology and Laboratory Medicine, Rutgers University-Robert W. Johnson Medical School, Piscataway, NJ, USA
| | - Yao Yao
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd., MDC 8, Tampa, FL, 33612, USA.
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Park SJ, Kim Y, Li C, Suh J, Sivapackiam J, Goncalves TM, Jarad G, Zhao G, Urano F, Sharma V, Chen YM. Blocking CHOP-dependent TXNIP shuttling to mitochondria attenuates albuminuria and mitigates kidney injury in nephrotic syndrome. Proc Natl Acad Sci U S A 2022; 119:e2116505119. [PMID: 35994650 PMCID: PMC9436335 DOI: 10.1073/pnas.2116505119] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 07/15/2022] [Indexed: 11/18/2022] Open
Abstract
Albuminuria is a hallmark of glomerular disease of various etiologies. It is not only a symptom of glomerular disease but also a cause leading to glomerulosclerosis, interstitial fibrosis, and eventually, a decline in kidney function. The molecular mechanism underlying albuminuria-induced kidney injury remains poorly defined. In our genetic model of nephrotic syndrome (NS), we have identified CHOP (C/EBP homologous protein)-TXNIP (thioredoxin-interacting protein) as critical molecular linkers between albuminuria-induced ER dysfunction and mitochondria dyshomeostasis. TXNIP is a ubiquitously expressed redox protein that binds to and inhibits antioxidant enzyme, cytosolic thioredoxin 1 (Trx1), and mitochondrial Trx2. However, very little is known about the regulation and function of TXNIP in NS. By utilizing Chop-/- and Txnip-/- mice as well as 68Ga-Galuminox, our molecular imaging probe for detection of mitochondrial reactive oxygen species (ROS) in vivo, we demonstrate that CHOP up-regulation induced by albuminuria drives TXNIP shuttling from nucleus to mitochondria, where it is required for the induction of mitochondrial ROS. The increased ROS accumulation in mitochondria oxidizes Trx2, thus liberating TXNIP to associate with mitochondrial nod-like receptor protein 3 (NLRP3) to activate inflammasome, as well as releasing mitochondrial apoptosis signal-regulating kinase 1 (ASK1) to induce mitochondria-dependent apoptosis. Importantly, inhibition of TXNIP translocation and mitochondrial ROS overproduction by CHOP deletion suppresses NLRP3 inflammasome activation and p-ASK1-dependent mitochondria apoptosis in NS. Thus, targeting TXNIP represents a promising therapeutic strategy for the treatment of NS.
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Affiliation(s)
- Sun-Ji Park
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - Yeawon Kim
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - Chuang Li
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - Junwoo Suh
- Department of Biomedical Engineering, Case Western Reserve University, Cleveland, OH 44106
| | - Jothilingam Sivapackiam
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110
| | - Tassia M. Goncalves
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO 63110
| | - George Jarad
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - Guoyan Zhao
- Department of Neuroscience, Washington University School of Medicine, St. Louis, MO 63110
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO 63110
| | - Fumihiko Urano
- Division of Endocrinology, Metabolism, and Lipid Research, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
| | - Vijay Sharma
- Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO 63110
- Department of Neurology, Washington University School of Medicine, St. Louis, MO 63110
- Department of Biomedical Engineering, School of Engineering & Applied Science, Washington University, St. Louis, MO 63105
| | - Ying Maggie Chen
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110
- Department of Cell Biology & Physiology, Washington University School of Medicine, St. Louis, MO 63110
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6
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Raghubar AM, Pham DT, Tan X, Grice LF, Crawford J, Lam PY, Andersen SB, Yoon S, Teoh SM, Matigian NA, Stewart A, Francis L, Ng MSY, Healy HG, Combes AN, Kassianos AJ, Nguyen Q, Mallett AJ. Spatially Resolved Transcriptomes of Mammalian Kidneys Illustrate the Molecular Complexity and Interactions of Functional Nephron Segments. Front Med (Lausanne) 2022; 9:873923. [PMID: 35872784 PMCID: PMC9300864 DOI: 10.3389/fmed.2022.873923] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 05/23/2022] [Indexed: 11/30/2022] Open
Abstract
Available transcriptomes of the mammalian kidney provide limited information on the spatial interplay between different functional nephron structures due to the required dissociation of tissue with traditional transcriptome-based methodologies. A deeper understanding of the complexity of functional nephron structures requires a non-dissociative transcriptomics approach, such as spatial transcriptomics sequencing (ST-seq). We hypothesize that the application of ST-seq in normal mammalian kidneys will give transcriptomic insights within and across species of physiology at the functional structure level and cellular communication at the cell level. Here, we applied ST-seq in six mice and four human kidneys that were histologically absent of any overt pathology. We defined the location of specific nephron structures in the captured ST-seq datasets using three lines of evidence: pathologist's annotation, marker gene expression, and integration with public single-cell and/or single-nucleus RNA-sequencing datasets. We compared the mouse and human cortical kidney regions. In the human ST-seq datasets, we further investigated the cellular communication within glomeruli and regions of proximal tubules-peritubular capillaries by screening for co-expression of ligand-receptor gene pairs. Gene expression signatures of distinct nephron structures and microvascular regions were spatially resolved within the mouse and human ST-seq datasets. We identified 7,370 differentially expressed genes (p adj < 0.05) distinguishing species, suggesting changes in energy production and metabolism in mouse cortical regions relative to human kidneys. Hundreds of potential ligand-receptor interactions were identified within glomeruli and regions of proximal tubules-peritubular capillaries, including known and novel interactions relevant to kidney physiology. Our application of ST-seq to normal human and murine kidneys confirms current knowledge and localization of transcripts within the kidney. Furthermore, the generated ST-seq datasets provide a valuable resource for the kidney community that can be used to inform future research into this complex organ.
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Affiliation(s)
- Arti M. Raghubar
- Kidney Health Service, Royal Brisbane and Women's Hospital, Herston, QLD, Australia
- Conjoint Internal Medicine Laboratory, Chemical Pathology, Pathology Queensland, Health Support Queensland, Herston, QLD, Australia
- Faculty of Medicine, University of Queensland, Brisbane, QLD, Australia
- Anatomical Pathology, Pathology Queensland, Health Support Queensland, Herston, QLD, Australia
- Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, Australia
| | - Duy T. Pham
- Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, Australia
| | - Xiao Tan
- Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, Australia
| | - Laura F. Grice
- Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, Australia
- School of Biomedical Sciences, The University of Queensland, Brisbane, QLD, Australia
| | - Joanna Crawford
- Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, Australia
| | - Pui Yeng Lam
- Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, Australia
| | - Stacey B. Andersen
- Genome Innovation Hub, University of Queensland, Brisbane, QLD, Australia
- UQ Sequencing Facility, Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, Australia
| | - Sohye Yoon
- Genome Innovation Hub, University of Queensland, Brisbane, QLD, Australia
| | - Siok Min Teoh
- UQ Diamantina Institute, Faculty of Medicine, The University of Queensland, Woolloongabba, QLD, Australia
| | - Nicholas A. Matigian
- QCIF Facility for Advanced Bioinformatics, Institute for Molecular Bioscience, The University of Queensland, Brisbane, QLD, Australia
| | - Anne Stewart
- Anatomical Pathology, Pathology Queensland, Health Support Queensland, Herston, QLD, Australia
| | - Leo Francis
- Anatomical Pathology, Pathology Queensland, Health Support Queensland, Herston, QLD, Australia
| | - Monica S. Y. Ng
- Kidney Health Service, Royal Brisbane and Women's Hospital, Herston, QLD, Australia
- Conjoint Internal Medicine Laboratory, Chemical Pathology, Pathology Queensland, Health Support Queensland, Herston, QLD, Australia
- Faculty of Medicine, University of Queensland, Brisbane, QLD, Australia
- Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, Australia
- Nephrology Department, Princess Alexandra Hospital, Woolloongabba, QLD, Australia
| | - Helen G. Healy
- Kidney Health Service, Royal Brisbane and Women's Hospital, Herston, QLD, Australia
- Conjoint Internal Medicine Laboratory, Chemical Pathology, Pathology Queensland, Health Support Queensland, Herston, QLD, Australia
- Faculty of Medicine, University of Queensland, Brisbane, QLD, Australia
| | - Alexander N. Combes
- Department of Anatomy and Developmental Biology, Stem Cells and Development Program, Monash Biomedicine Discovery Institute, Monash University, Melbourne, VIC, Australia
| | - Andrew J. Kassianos
- Kidney Health Service, Royal Brisbane and Women's Hospital, Herston, QLD, Australia
- Conjoint Internal Medicine Laboratory, Chemical Pathology, Pathology Queensland, Health Support Queensland, Herston, QLD, Australia
- Faculty of Medicine, University of Queensland, Brisbane, QLD, Australia
| | - Quan Nguyen
- Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, Australia
| | - Andrew J. Mallett
- Faculty of Medicine, University of Queensland, Brisbane, QLD, Australia
- Institute for Molecular Bioscience, University of Queensland, Brisbane, QLD, Australia
- College of Medicine & Dentistry, James Cook University, Townsville, Queensland, QLD, Australia
- Department of Renal Medicine, Townsville University Hospital, Townsville, Queensland, QLD, Australia
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Sugden CJ, Iorio V, Troughton LD, Liu K, Morais MRPT, Lennon R, Bou-Gharios G, Hamill KJ. Laminin N-terminus α31 expression during development is lethal and causes widespread tissue-specific defects in a transgenic mouse model. FASEB J 2022; 36:e22318. [PMID: 35648586 PMCID: PMC9328196 DOI: 10.1096/fj.202002588rrr] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 03/28/2022] [Accepted: 04/05/2022] [Indexed: 11/11/2022]
Abstract
Laminins (LMs) are essential components of all basement membranes where they regulate an extensive array of tissue functions. Alternative splicing from the laminin α3 gene produces a non‐laminin but netrin‐like protein, Laminin N terminus α31 (LaNt α31). LaNt α31 is widely expressed in intact tissue and is upregulated in epithelial cancers and during wound healing. In vitro functional studies have shown that LaNt α31 can influence numerous aspects of epithelial cell behavior via modifying matrix organization, suggesting a new model of laminin auto‐regulation. However, the function of this protein has not been established in vivo. Here, a mouse transgenic line was generated using the ubiquitin C promoter to drive inducible expression of LaNt α31. When expression was induced at embryonic day 15.5, LaNt α31 transgenic animals were not viable at birth, exhibiting localized regions of erythema. Histologically, the most striking defect was widespread evidence of extravascular bleeding across multiple tissues. Additionally, LaNt α31 transgene expressing animals exhibited kidney epithelial detachment, tubular dilation, disruption of the epidermal basal cell layer and of the hair follicle outer root sheath, and ~50% reduction of cell numbers in the liver, associated with depletion of hematopoietic erythrocytic foci. These findings provide the first in vivo evidence that LaNt α31 can influence tissue morphogenesis.
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Affiliation(s)
- Conor J Sugden
- Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, UK
| | - Valentina Iorio
- Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, UK
| | - Lee D Troughton
- Department of Cell and Molecular Physiology, Stritch School of Medicine, Loyola University Chicago, Maywood, Illinois, USA
| | - Ke Liu
- Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, UK
| | - Mychel R P T Morais
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, The University of Manchester, Manchester, UK
| | - Rachel Lennon
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, The University of Manchester, Manchester, UK
| | - George Bou-Gharios
- Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, UK
| | - Kevin J Hamill
- Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, UK
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8
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Boyer O, Mollet G, Dorval G. Neurological involvement in monogenic podocytopathies. Pediatr Nephrol 2021; 36:3571-3583. [PMID: 33791874 DOI: 10.1007/s00467-020-04903-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/19/2020] [Revised: 10/27/2020] [Accepted: 12/11/2020] [Indexed: 01/22/2023]
Abstract
Genetic studies of hereditary nephrotic syndrome (NS) have identified more than 50 genes that, if mutated, are responsible for monogenic forms of steroid-resistant NS (SRNS), either isolated or syndromic. Most of these genes encode proteins expressed in the podocyte with various functions such as transcription factors, mitochondrial proteins, or enzymes, but mainly structural proteins of the slit diaphragm (SD) as well as cytoskeletal binding and regulator proteins. Syndromic NS is sometimes associated with neurological features. Over recent decades, various studies have established links between the physiology of podocytes and neurons, both morphologically (slit diaphragm and synapse) and functionally (signaling platforms). Variants in genes expressed in different compartments of the podocyte and neurons are responsible for phenotypes associating kidney lesions with proteinuria (mainly Focal and Segmental Glomerulosclerosis (FSGS) or Diffuse Mesangial Sclerosis (DMS)) and central and/or peripheral neurological disorders. The Galloway-Mowat syndrome (GAMOS, OMIM#251300) associates neurological defects, microcephaly, and proteinuria and is caused by variants in genes encoding proteins of various functions (microtubule cytoskeleton regulation (WDR73), regulation of protein synthesis via transfer RNAs (KEOPS and WDR4 complexes)). Pierson syndrome (OMIM#609049) associating congenital nephrotic syndrome and central neurological and ophthalmological anomalies is secondary to variants in LAMB2, involved in glomerular and ocular basement membranes. Finally, Charcot-Marie-Tooth-FSGS (OMIM#614455) combines peripheral sensory-motor neuropathy and proteinuria and arises from INF2 variants, resulting in cytoskeletal polymerization defects. This review focuses on genetic syndromes associating nephrotic range proteinuria and neurological involvement and provides the latest advances in the description of these neuro-renal disorders.
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Affiliation(s)
- Olivia Boyer
- Service de Néphrologie Pédiatrique, AP-HP, Centre de Référence de maladies rénales rares de l'enfant et de l'adulte (MARHEA), Hôpital Necker - Enfants Malades, 149 Rue de Sèvres, 75015, Paris, France.
- Institut Imagine, Laboratoire des maladies rénales héréditaires, INSERM UMR 1163, Université de Paris, Paris, France.
| | - Géraldine Mollet
- Institut Imagine, Laboratoire des maladies rénales héréditaires, INSERM UMR 1163, Université de Paris, Paris, France
| | - Guillaume Dorval
- Institut Imagine, Laboratoire des maladies rénales héréditaires, INSERM UMR 1163, Université de Paris, Paris, France
- Service de Génétique Moléculaire, AP-HP, Hôpital Necker-Enfants Malades, Paris, France
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9
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Ning L, Suleiman HY, Miner JH. Synaptopodin deficiency exacerbates kidney disease in a mouse model of Alport syndrome. Am J Physiol Renal Physiol 2021; 321:F12-F25. [PMID: 34029143 DOI: 10.1152/ajprenal.00035.2021] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Synaptopodin (Synpo) is an actin-associated protein in podocyte foot processes. By generating mice that completely lack Synpo, we previously showed that Synpo is dispensable for normal kidney function. However, lack of Synpo worsened adriamycin-induced nephropathy, indicating a protective role for Synpo in injured podocytes. Here, we investigated whether lack of Synpo directly impacts a genetic disease, Alport syndrome (AS), because Synpo is reduced in podocytes of affected humans and mice; whether this is merely an association or pathogenic is unknown. We used collagen type IV-α5 (Col4a5) mutant mice, which model X-linked AS, showing glomerular basement membrane (GBM) abnormalities, eventual foot process effacement, and progression to end-stage kidney disease. We intercrossed mice carrying mutations in Synpo and Col4a5 to produce double-mutant mice. Urine and tissue were taken at select time points to evaluate albuminuria, histopathology, and glomerular capillary wall composition and ultrastructure. Lack of Synpo in Col4a5-/Y, Col4a5-/-, or Col4a5+/- Alport mice led to the acceleration of disease progression, including more severe proteinuria and glomerulosclerosis. Absence of Synpo attenuated the shift of myosin IIA from the podocyte cell body and major processes to actin cables near the GBM in the areas of effacement. We speculate that this is mechanistically associated with enhanced loss of podocytes due to easier detachment from the GBM. We conclude that Synpo deletion exacerbates the disease phenotype in Alport mice, revealing the podocyte actin cytoskeleton as a target for therapy in patients with AS.NEW & NOTEWORTHY Alport syndrome (AS) is a hereditary disease of the glomerular basement with hematuria and proteinuria. Podocytes eventually exhibit foot process effacement, indicating actin cytoskeletal changes. To investigate how cytoskeletal changes impact podocytes, we generated Alport mice lacking synaptopodin, an actin-binding protein in foot processes. Analysis showed a more rapid disease progression, demonstrating that synaptopodin is protective. This suggests that the actin cytoskeleton is a target for therapy in AS and perhaps other glomerular diseases.
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Affiliation(s)
- Liang Ning
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Hani Y Suleiman
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
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10
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Wang X, Xiao H, Su B, Ren Y, Ding J, Wang F. LAMB2 novel variant c.2885-9 C>A affects RNA splicing in a minigene assay. Mol Genet Genomic Med 2021; 9:e1704. [PMID: 33982833 PMCID: PMC8372075 DOI: 10.1002/mgg3.1704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Revised: 03/22/2021] [Accepted: 04/09/2021] [Indexed: 11/24/2022] Open
Abstract
Background Both Pierson syndrome (PS) and isolated nephrotic syndrome can be caused by LAMB2 biallelic pathogenic variants. Only 15 causative splicing variants in the LAMB2 gene have been reported. However, the pathogenicity of most of these variants has not been verified, which may lead to incorrect interpretation of the functional consequence of these variants. Methods Using high‐throughput DNA sequencing and Sanger sequencing, we detected variants in a female with clinically suspected PS. A minigene splicing assay was performed to assess the effect of LAMB2 intron 20 c.2885‐9C>A on RNA splicing. We also performed the immunohistochemical analysis of laminin beta‐2 in kidney tissues. Results Two novel LAMB2 heteroallelic variants were found: a paternally inherited variant c.2885‐9C>A in intron 20 and a maternally inherited variant c. 3658C>T (p. (Gln1220Ter)). In vitro minigene assay showed that the variant c.2885‐9C>A caused erroneous integration of a 7 bp sequence into intron 20. Immunohistochemical analysis revealed the absence of glomerular expression of laminin beta‐2, the protein encoded by LAMB2. Conclusion We demonstrated the impact of a novel LAMB2 intronic variant on RNA splicing using the minigene assay firstly. Our results extend the mutational spectrum of LAMB2.
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Affiliation(s)
- Xiaoyuan Wang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Huijie Xiao
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Baige Su
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Yali Ren
- Laboratory of Electron Microscopy, Ultrastructural Pathology Center, Peking University First Hospital, Beijing, China
| | - Jie Ding
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Fang Wang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
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11
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Li L, Li H, Wang L, Bu T, Liu S, Mao B, Cheng CY. A local regulatory network in the testis mediated by laminin and collagen fragments that supports spermatogenesis. Crit Rev Biochem Mol Biol 2021; 56:236-254. [PMID: 33761828 DOI: 10.1080/10409238.2021.1901255] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
It is almost five decades since the discovery of the hypothalamic-pituitary-testicular axis. This refers to the hormonal axis that connects the hypothalamus, pituitary gland and testes, which in turn, regulates the production of spermatozoa through spermatogenesis in the seminiferous tubules, and testosterone through steroidogenesis by Leydig cells in the interstitium, of the testes. Emerging evidence has demonstrated the presence of a regulatory network across the seminiferous epithelium utilizing bioactive molecules produced locally at specific domains of the epithelium. Studies have shown that biologically active fragments are produced from structural laminin and collagen chains in the basement membrane. Additionally, bioactive peptides are also produced locally in non-basement membrane laminin chains at the Sertoli-spermatid interface known as apical ectoplasmic specialization (apical ES, a testis-specific actin-based anchoring junction type). These bioactive peptides are derived from structural laminins and/or collagens at the corresponding sites through proteolytic cleavage by matrix metalloproteinases (MMPs). They in turn serve as autocrine and/or paracrine factors to modulate and coordinate cellular events across the epithelium by linking the apical and basal compartments, the apical and basal ES, the blood-testis barrier (BTB), and the basement membrane of the tunica propria. The cellular events supported by these bioactive peptides/fragments include the release of spermatozoa at spermiation, remodeling of the immunological barrier to facilitate the transport of preleptotene spermatocytes across the BTB, and the transport of haploid spermatids across the epithelium to support spermiogenesis. In this review, we critically evaluate these findings. Our goal is to identify research areas that deserve attentions in future years. The proposed research also provides the much needed understanding on the biology of spermatogenesis supported by a local network of regulatory biomolecules.
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Affiliation(s)
- Linxi Li
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China.,The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA
| | - Huitao Li
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China.,The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA
| | - Lingling Wang
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China.,The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA
| | - Tiao Bu
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China
| | - Shiwen Liu
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China.,The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA
| | - Baiping Mao
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China.,The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA
| | - C Yan Cheng
- The Second Affiliated Hospital and Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, China.,The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, Population Council, New York, NY, USA
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12
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Bamberger C, Pankow S, Martínez-Bartolomé S, Diedrich J, Park R, Yates J. The Host Interactome of Spike Expands the Tropism of SARS-CoV-2. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2021:2021.02.16.431318. [PMID: 33619478 PMCID: PMC7899442 DOI: 10.1101/2021.02.16.431318] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The SARS-CoV-2 virus causes severe acute respiratory syndrome (COVID-19) and has rapidly created a global pandemic. Patients that survive may face a slow recovery with long lasting side effects that can afflict different organs. SARS-CoV-2 primarily infects epithelial airway cells that express the host entry receptor Angiotensin Converting Enzyme 2 (ACE2) which binds to spike protein trimers on the surface of SARS-CoV-2 virions. However, SARS-CoV-2 can spread to other tissues even though they are negative for ACE2. To gain insight into the molecular constituents that might influence SARS-CoV-2 tropism, we determined which additional host factors engage with the viral spike protein in disease-relevant human bronchial epithelial cells (16HBEo-). We found that spike recruited the extracellular proteins laminin and thrombospondin and was retained in the endoplasmatic reticulum (ER) by the proteins DJB11 and FBX2 which support re-folding or degradation of nascent proteins in the ER. Because emerging mutations of the spike protein potentially impact the virus tropism, we compared the interactome of D614 spike with that of the rapidly spreading G614 mutated spike. More D614 than G614 spike associated with the proteins UGGT1, calnexin, HSP7A and GRP78/BiP which ensure glycosylation and folding of proteins in the ER. In contrast to G614 spike, D614 spike was endoproteolytically cleaved, and the N-terminal S1 domain was degraded in the ER even though C-terminal 'S2 only' proteoforms remained present. D614 spike also bound more laminin than G614 spike, which suggested that extracellular laminins may function as co-factor for an alternative, 'S2 only' dependent virus entry. Because the host interactome determines whether an infection is productive, we developed a novel proteome-based cell type set enrichment analysis (pCtSEA). With pCtSEA we determined that the host interactome of the spike protein may extend the tropism of SARS-CoV-2 beyond mucous epithelia to several different cell types, including macrophages and epithelial cells in the nephron. An 'S2 only' dependent, alternative infection of additional cell types with SARS-CoV-2 may impact vaccination strategies and may provide a molecular explanation for a severe or prolonged progression of disease in select COVID-19 patients.
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Affiliation(s)
- Casimir Bamberger
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | - Sandra Pankow
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | | | - Jolene Diedrich
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | - Robin Park
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | - John Yates
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
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13
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Abstract
The glomerular basement membrane (GBM) is a key component of the glomerular capillary wall and is essential for kidney filtration. The major components of the GBM include laminins, type IV collagen, nidogens and heparan sulfate proteoglycans. In addition, the GBM harbours a number of other structural and regulatory components and provides a reservoir for growth factors. New technologies have improved our ability to study the composition and assembly of basement membranes. We now know that the GBM is a complex macromolecular structure that undergoes key transitions during glomerular development. Defects in GBM components are associated with a range of hereditary human diseases such as Alport syndrome, which is caused by defects in the genes COL4A3, COL4A4 and COL4A5, and Pierson syndrome, which is caused by variants in LAMB2. In addition, the GBM is affected by acquired autoimmune disorders and metabolic diseases such as diabetes mellitus. Current treatments for diseases associated with GBM involvement aim to reduce intraglomerular pressure and to treat the underlying cause where possible. As our understanding about the maintenance and turnover of the GBM improves, therapies to replace GBM components or to stimulate GBM repair could translate into new therapies for patients with GBM-associated disease.
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14
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Uchio-Yamada K, Yasuda K, Monobe Y, Akagi KI, Suzuki O, Manabe N. Tensin2 is important for podocyte-glomerular basement membrane interaction and integrity of the glomerular filtration barrier. Am J Physiol Renal Physiol 2020; 318:F1520-F1530. [PMID: 32390516 DOI: 10.1152/ajprenal.00055.2020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Tensin2 (Tns2), an integrin-linked protein, is enriched in podocytes within the glomerulus. Previous studies have revealed that Tns2-deficient mice exhibit defects of the glomerular basement membrane (GBM) soon after birth in a strain-dependent manner. However, the mechanisms for the onset of defects caused by Tns2 deficiency remains unidentified. Here, we aimed to determine the role of Tns2 using newborn Tns2-deficient mice and murine primary podocytes. Ultrastructural analysis revealed that developing glomeruli during postnatal nephrogenesis exhibited abnormal GBM processing due to ectopic laminin-α2 accumulation followed by GBM thickening. In addition, analysis of primary podocytes revealed that Tns2 deficiency led to impaired podocyte-GBM interaction and massive expression of laminin-α2 in podocytes. Our study suggests that weakened podocyte-GBM interaction due to Tns2 deficiency causes increased mechanical stress on podocytes by continuous daily filtration after birth, resulting in stressed podocytes ectopically producing laminin-α2, which interrupts GBM processing. We conclude that Tns2 plays important roles in the podocyte-GBM interaction and maintenance of the glomerular filtration barrier.
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Affiliation(s)
- Kozue Uchio-Yamada
- Laboratory of Animal Models for Human Diseases, National Institutes of Biomedical Innovation, Health and Nutrition, Ibaraki, Osaka, Japan
| | - Keiko Yasuda
- Department of Nephrology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Yoko Monobe
- Section of Laboratory Equipment, National Institutes of Biomedical Innovation, Health and Nutrition, Ibaraki, Osaka, Japan
| | - Ken-Ichi Akagi
- Section of Laboratory Equipment, National Institutes of Biomedical Innovation, Health and Nutrition, Ibaraki, Osaka, Japan
| | - Osamu Suzuki
- Laboratory of Animal Models for Human Diseases, National Institutes of Biomedical Innovation, Health and Nutrition, Ibaraki, Osaka, Japan
| | - Noboru Manabe
- Department of Human Sciences, Osaka International University, Moriguchi, Osaka, Japan
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15
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Affiliation(s)
- Minkyung Kang
- From the Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA
| | - Yao Yao
- From the Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA
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16
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Funk SD, Bayer RH, McKee KK, Okada K, Nishimune H, Yurchenco PD, Miner JH. A deletion in the N-terminal polymerizing domain of laminin β2 is a new mouse model of chronic nephrotic syndrome. Kidney Int 2020; 98:133-146. [PMID: 32456966 DOI: 10.1016/j.kint.2020.01.033] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Revised: 01/14/2020] [Accepted: 01/21/2020] [Indexed: 10/25/2022]
Abstract
The importance of the glomerular basement membrane (GBM) in glomerular filtration is underscored by the manifestations of Alport and Pierson syndromes, caused by defects in type IV collagen α3α4α5 and the laminin β2 chain, respectively. Lamb2 null mice, which model the most severe form of Pierson syndrome, exhibit proteinuria prior to podocyte foot process effacement and are therefore useful for studying GBM permselectivity. We hypothesize that some LAMB2 missense mutations that cause mild forms of Pierson syndrome induce GBM destabilization with delayed effects on podocytes. While generating a CRISPR/Cas9-mediated analogue of a human LAMB2 missense mutation in mice, we identified a 44-amino acid deletion (LAMB2-Del44) within the laminin N-terminal domain, a domain mediating laminin polymerization. Laminin heterotrimers containing LAMB2-Del44 exhibited a 90% reduction in polymerization in vitro that was partially rescued by type IV collagen and nidogen. Del44 mice showed albuminuria at 1.8-6.0 g/g creatinine (ACR) at one to two months, plateauing at an average 200 g/g ACR at 3.7 months, when GBM thickening and hallmarks of nephrotic syndrome were first observed. Despite the massive albuminuria, some Del44 mice survived for up to 15 months. Blood urea nitrogen was modestly elevated at seven-nine months. Eight to nine-month-old Del44 mice exhibited glomerulosclerosis and interstitial fibrosis. Similar to Lamb2-/- mice, proteinuria preceded foot process effacement. Foot processes were widened but not effaced at one-two months despite the high ACRs. At three months some individual foot processes were still observed amid widespread effacement. Thus, our chronic model of nephrotic syndrome may prove useful to study filtration mechanisms, long-term proteinuria with preserved kidney function, and to test therapeutics.
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Affiliation(s)
- Steven D Funk
- Department of Internal Medicine, Division of Nephrology, Washington University, St. Louis, Missouri, USA
| | - Raymond H Bayer
- Department of Internal Medicine, Division of Nephrology, Washington University, St. Louis, Missouri, USA
| | - Karen K McKee
- Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey, USA
| | - Kazushi Okada
- Department of Anatomy and Cell Biology, University of Kansas School of Medicine, Kansas City, Kansas, USA
| | - Hiroshi Nishimune
- Department of Anatomy and Cell Biology, University of Kansas School of Medicine, Kansas City, Kansas, USA
| | - Peter D Yurchenco
- Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey, USA
| | - Jeffrey H Miner
- Department of Internal Medicine, Division of Nephrology, Washington University, St. Louis, Missouri, USA.
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17
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Kuure S, Sariola H. Mouse Models of Congenital Kidney Anomalies. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1236:109-136. [PMID: 32304071 DOI: 10.1007/978-981-15-2389-2_5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Congenital anomalies of the kidney and urinary tract (CAKUT) are common birth defects, which cause the majority of chronic kidney diseases in children. CAKUT covers a wide range of malformations that derive from deficiencies in embryonic kidney and lower urinary tract development, including renal aplasia, hypodysplasia, hypoplasia, ectopia, and different forms of ureter abnormalities. The majority of the genetic causes of CAKUT remain unknown. Research on mutant mice has identified multiple genes that critically regulate renal differentiation. The data generated from this research have served as an excellent resource to identify the genetic bases of human kidney defects and have led to significantly improved diagnostics. Furthermore, genetic data from human CAKUT studies have also revealed novel genes regulating kidney differentiation.
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Affiliation(s)
- Satu Kuure
- GM-Unit, Helsinki Institute of Life Science, University of Helsinki, Helsinki, Finland. .,Stem Cells and Metabolism Research Program, Faculty of Medicine, University of Helsinki, Helsinki, Finland. .,Medicum, Faculty of Medicine, University of Helsinki, Helsinki, Finland.
| | - Hannu Sariola
- Medicum, Faculty of Medicine, University of Helsinki, Helsinki, Finland.,Paediatric Pathology, HUSLAB, Helsinki University Central Hospital, Helsinki, Finland
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18
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Cinà DP, Ketela T, Brown KR, Chandrashekhar M, Mero P, Li C, Onay T, Fu Y, Han Z, Saleem M, Moffat J, Quaggin SE. Forward genetic screen in human podocytes identifies diphthamide biosynthesis genes as regulators of adhesion. Am J Physiol Renal Physiol 2019; 317:F1593-F1604. [PMID: 31566424 PMCID: PMC6962514 DOI: 10.1152/ajprenal.00195.2019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 08/28/2019] [Accepted: 09/25/2019] [Indexed: 02/06/2023] Open
Abstract
Podocyte function is tightly linked to the complex organization of its cytoskeleton and adhesion to the underlying glomerular basement membrane. Adhesion of cultured podocytes to a variety of substrates is reported to correlate with podocyte health. To identify novel genes that are important for podocyte function, we designed an in vitro genetic screen based on podocyte adhesion to plates coated with either fibronectin or soluble Fms-like tyrosine kinase-1 (sFLT1)/Fc. A genome-scale pooled RNA interference screen on immortalized human podocytes identified 77 genes that increased adhesion to fibronectin, 101 genes that increased adhesion to sFLT1/Fc, and 44 genes that increased adhesion to both substrates when knocked down. Multiple shRNAs against diphthamide biosynthesis protein 1-4 (DPH1-DPH4) were top hits for increased adhesion. Immortalized human podocyte cells stably expressing these hairpins displayed increased adhesion to both substrates. We then used CRISPR-Cas9 to generate podocyte knockout cells for DPH1, DPH2, or DPH3, which also displayed increased adhesion to both fibronectin and sFLT1/Fc, as well as a spreading defect. Finally, we showed that Drosophila nephrocyte-specific knockdown of Dph1, Dph2, and Dph4 resulted in altered nephrocyte function. In summary, we report here a novel high-throughput method to identify genes important for podocyte function. Given the central role of podocyte adhesion as a marker of podocyte health, these data are a rich source of candidate regulators of glomerular disease.
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Affiliation(s)
- Davide P Cinà
- Feinberg Cardiovascular and Renal Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois
- Division of Nephrology and Hypertension, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Troy Ketela
- Donnelly Centre, Banting and Best Department of Medical Research, University of Toronto, Toronto, Ontario, Canada
| | - Kevin R Brown
- Donnelly Centre, Banting and Best Department of Medical Research, University of Toronto, Toronto, Ontario, Canada
| | - Megha Chandrashekhar
- Donnelly Centre, Banting and Best Department of Medical Research, University of Toronto, Toronto, Ontario, Canada
| | - Patricia Mero
- Donnelly Centre, Banting and Best Department of Medical Research, University of Toronto, Toronto, Ontario, Canada
| | - Chengjin Li
- Tanenbaum-Lunenfeld Research Institute, University of Toronto, Toronto, Ontario, Canada
| | - Tuncer Onay
- Feinberg Cardiovascular and Renal Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois
- Division of Nephrology and Hypertension, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Yulong Fu
- Center for Genetic Medicine Research, Children's National Health System, Washington, District of Columbia
| | - Zhe Han
- Center for Genetic Medicine Research, Children's National Health System, Washington, District of Columbia
| | - Moin Saleem
- School of Clinical Sciences, Children's Renal Unit and Academic Renal Unit, University of Bristol, Bristol, United Kingdom
| | - Jason Moffat
- Donnelly Centre, Banting and Best Department of Medical Research, University of Toronto, Toronto, Ontario, Canada
| | - Susan E Quaggin
- Feinberg Cardiovascular and Renal Research Institute, Northwestern University Feinberg School of Medicine, Chicago, Illinois
- Division of Nephrology and Hypertension, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois
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19
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Abrahamson DR, Steenhard BM, Stroganova L, Zelenchuk A, St John PL, Petroff MG, Patarroyo M, Borza DB. Maternal alloimmune IgG causes anti-glomerular basement membrane disease in perinatal transgenic mice that express human laminin α5. Kidney Int 2019; 96:1320-1331. [PMID: 31530475 DOI: 10.1016/j.kint.2019.06.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 06/06/2019] [Accepted: 06/14/2019] [Indexed: 12/31/2022]
Abstract
Mammalian immune systems are not mature until well after birth. However, transfer of maternal IgG to the fetus and newborn usually provides immunoprotection from infectious diseases. IgG transfer occurs before birth in humans across the placenta and continues after birth across the intestine in many mammalian species, including rodents. Transfer, which is mediated by the neonatal IgG Fc receptor, occurs by transcytosis across placental syncytiotrophoblasts and intestinal epithelium. Although maternal IgG is generally beneficial, harmful maternal allo- and autoantibodies can also be transferred to the fetus/infant, resulting in serious disease. To test this we generated transgenic mice that widely express human laminin α5 in their basement membranes. When huLAMA5 transgenic males were crossed with wild-type females, there was a maternal anti-human laminin α5 immune response. Maternal IgG alloantibody crossed the yolk sac and post-natal intestine invivo and bound in bright, linear patterns to kidney glomerular basement membranes of transgenic fetuses/neonates but not those of wild-type siblings. By postnatal day 18, most transgenic mice were proteinuric, had glomerular C3 deposits and inflammatory cell infiltrates, thickened and split glomerular basement membranes, and podocyte foot process effacement. Thus, our novel model of perinatal anti-glomerular basement membrane disease may prove useful for studying pediatric glomerulopathies, formation of the fetomaternal interface, and maternal alloimmunization.
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Affiliation(s)
- Dale R Abrahamson
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, Kansas, USA; The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA.
| | - Brooke M Steenhard
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, Kansas, USA; The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Larysa Stroganova
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, Kansas, USA; The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Adrian Zelenchuk
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, Kansas, USA; The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Patricia L St John
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, Kansas, USA; The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Margaret G Petroff
- Department of Pathobiology and Investigative Medicine, Michigan State University, East Lansing, Michigan, USA
| | - Manuel Patarroyo
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institute, Stockholm, Sweden
| | - Dorin Bogdan Borza
- Department of Microbiology, Immunology and Physiology, Meharry Medical College, Nashville, Tennessee, USA
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20
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Cellular and molecular mechanisms of kidney fibrosis. Mol Aspects Med 2018; 65:16-36. [PMID: 29909119 DOI: 10.1016/j.mam.2018.06.002] [Citation(s) in RCA: 280] [Impact Index Per Article: 46.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 06/12/2018] [Indexed: 12/14/2022]
Abstract
Renal fibrosis is the final pathological process common to any ongoing, chronic kidney injury or maladaptive repair. It is considered as the underlying pathological process of chronic kidney disease (CKD), which affects more than 10% of world population and for which treatment options are limited. Renal fibrosis is defined by excessive deposition of extracellular matrix, which disrupts and replaces the functional parenchyma that leads to organ failure. Kidney's histological structure can be divided into three main compartments, all of which can be affected by fibrosis, specifically termed glomerulosclerosis in glomeruli, interstitial fibrosis in tubulointerstitium and arteriosclerosis and perivascular fibrosis in vasculature. In this review, we summarized the different appearance, cellular origin and major emerging processes and mediators of fibrosis in each compartment. We also depicted and discussed the challenges in translation of anti-fibrotic treatment to clinical practice and discuss possible solutions and future directions.
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21
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Lin MH, Miller JB, Kikkawa Y, Suleiman HY, Tryggvason K, Hodges BL, Miner JH. Laminin-521 Protein Therapy for Glomerular Basement Membrane and Podocyte Abnormalities in a Model of Pierson Syndrome. J Am Soc Nephrol 2018; 29:1426-1436. [PMID: 29472414 PMCID: PMC5967757 DOI: 10.1681/asn.2017060690] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 01/14/2018] [Indexed: 12/22/2022] Open
Abstract
Background Laminin α5β2γ1 (LM-521) is a major component of the GBM. Mutations in LAMB2 that prevent LM-521 synthesis and/or secretion cause Pierson syndrome, a rare congenital nephrotic syndrome with diffuse mesangial sclerosis and ocular and neurologic defects. Because the GBM is uniquely accessible to plasma, which permeates endothelial cell fenestrae, we hypothesized that intravenous delivery of LM-521 could replace the missing LM-521 in the GBM of Lamb2 mutant mice and restore glomerular permselectivity.Methods We injected human LM-521 (hLM-521), a macromolecule of approximately 800 kD, into the retro-orbital sinus of Lamb2-/- pups daily. Deposition of hLM-521 into the GBM was investigated by fluorescence microscopy. We assayed the effects of hLM-521 on glomerular permselectivity by urinalysis and the effects on podocytes by desmin immunostaining and ultrastructural analysis of podocyte architecture.Results Injected hLM-521 rapidly and stably accumulated in the GBM of all glomeruli. Super-resolution imaging showed that hLM-521 accumulated in the correct orientation in the GBM, primarily on the endothelial aspect. Treatment with hLM-521 greatly reduced the expression of the podocyte injury marker desmin and attenuated the foot process effacement observed in untreated pups. Moreover, treatment with hLM-521 delayed the onset of proteinuria but did not prevent nephrotic syndrome, perhaps due to its absence from the podocyte aspect of the GBM.Conclusions These studies show that GBM composition and function can be altered in vivovia vascular delivery of even very large proteins, which may advance therapeutic options for patients with abnormal GBM composition, whether genetic or acquired.
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Affiliation(s)
- Meei-Hua Lin
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Joseph B Miller
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Yamato Kikkawa
- Department of Clinical Biochemistry, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Hani Y Suleiman
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| | - Karl Tryggvason
- Cardiovascular and Metabolic Disorders Program, Duke-NUS Medical School, Singapore, Singapore
- Department of Medical Biochemistry and Biophysics, Karolinska Institute, Stockholm, Sweden; and
| | | | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri;
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22
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Beaufils C, Farlay D, Machuca-Gayet I, Fassier A, Zenker M, Freychet C, Bonnelye E, Bertholet-Thomas A, Ranchin B, Bacchetta J. Skeletal impairment in Pierson syndrome: Is there a role for lamininβ2 in bone physiology? Bone 2018; 106:187-193. [PMID: 29051055 DOI: 10.1016/j.bone.2017.10.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 10/10/2017] [Accepted: 10/12/2017] [Indexed: 01/15/2023]
Abstract
INTRODUCTION Pierson syndrome is caused by a mutation of LAMB2, encoding for laminin β2. Clinical phenotype is variable but usually associates congenital nephrotic syndrome (CNS) and ocular abnormalities. Neuromuscular impairment has also been described. METHODS We report on a 15-year old girl, suffering from Pierson Syndrome, who developed severe bone deformations during puberty. This patient initially displayed CNS and microcoria, leading to the clinical diagnosis of Pierson syndrome. Genetic analysis revealed a truncating mutation and a splice site mutation of LAMB2. The patient received a renal transplantation (R-Tx) at the age of 3. After R-Tx, renal evolution was simple, the patient receiving low-dose corticosteroids, tacrolimus and mycophenolate mofetil. At the age of 12, bone deformations progressively appeared. At the time of bone impairment, renal function was subnormal (glomerular filtration rate using iohexol clearance 50mL/min per 1.73m2), and parameters of calcium/phosphate metabolism were normal (calcium 2.45mmol/L, phosphorus 1.30mmol/L, PTH 81ng/L, ALP 334U/L, 25OH-D 73nmol/L). Radiographs showed major deformations such as scoliosis, genu varum and diffuse epiphyseal abnormalities. A high resolution scanner (HR-pQCT) was performed, demonstrating a bone of "normal low" quantity and quality; major radial and cubital deformations were observed. Stainings of laminin β2 were performed on bone and renal samples from the patient and healthy controls: as expected, laminin β2 was expressed in the control kidney but not in the patient's renal tissue, and a similar pattern was observed in bone. CONCLUSION This is the first case of skeletal impairment ever described in Pierson syndrome. Integrin α3β1, receptor for laminin β2, are found in podocytes and osteoblasts, and the observation of both the presence of laminin β2 staining in healthy bone and its absence in the patient's bone raises the question of a potential role of laminin β2 in bone physiology.
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Affiliation(s)
- Camille Beaufils
- Centre de Référence des Maladies Rénales Rares, Hôpital Femme Mère Enfant, Hospices, Civils de Lyon, 69677 Bron, France.
| | - Delphine Farlay
- INSERM, UMR 1033, Université Claude Bernard Lyon 1, Lyon, France
| | | | - Alice Fassier
- Service de Chirurgie Orthopédique Pédiatrique, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Bron, France
| | - Martin Zenker
- Institute of Human Genetics, University Hospital Magdeburg, Germany
| | - Caroline Freychet
- Centre de Référence des Maladies Rénales Rares, Hôpital Femme Mère Enfant, Hospices, Civils de Lyon, 69677 Bron, France
| | - Edith Bonnelye
- INSERM, UMR 1033, Université Claude Bernard Lyon 1, Lyon, France
| | - Aurélia Bertholet-Thomas
- Centre de Référence des Maladies Rénales Rares, Hôpital Femme Mère Enfant, Hospices, Civils de Lyon, 69677 Bron, France
| | - Bruno Ranchin
- Centre de Référence des Maladies Rénales Rares, Hôpital Femme Mère Enfant, Hospices, Civils de Lyon, 69677 Bron, France
| | - Justine Bacchetta
- Centre de Référence des Maladies Rénales Rares, Hôpital Femme Mère Enfant, Hospices, Civils de Lyon, 69677 Bron, France; INSERM, UMR 1033, Université Claude Bernard Lyon 1, Lyon, France; Service de Chirurgie Orthopédique Pédiatrique, Hôpital Femme Mère Enfant, Hospices Civils de Lyon, Bron, France; Institute of Human Genetics, University Hospital Magdeburg, Germany; Faculté de Médecine Lyon Est, Université de Lyon, France, Lyon.
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23
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Abstract
The glomerular basement membrane (GBM) is a specialized structure with a significant role in maintaining the glomerular filtration barrier. This GBM is formed from the fusion of two basement membranes during development and its function in the filtration barrier is achieved by key extracellular matrix components including type IV collagen, laminins, nidogens, and heparan sulfate proteoglycans. The characteristics of specific matrix isoforms such as laminin-521 (α5β2γ1) and the α3α4α5 chain of type IV collagen are essential for the formation of a mature GBM and the restricted tissue distribution of these isoforms makes the GBM a unique structure. Detailed investigation of the GBM has been driven by the identification of inherited abnormalities in matrix proteins and the need to understand pathogenic mechanisms causing severe glomerular disease. A well-described hereditary GBM disease is Alport syndrome, associated with a progressive glomerular disease, hearing loss, and lens defects due to mutations in the genes COL4A3, COL4A4, or COL4A5. Other proteins associated with inherited diseases of the GBM include laminin β2 in Pierson syndrome and LMX1B in nail patella syndrome. The knowledge of these genetic mutations associated with GBM defects has enhanced our understanding of cell-matrix signaling pathways affected in glomerular disease. This review will address current knowledge of GBM-associated abnormalities and related signaling pathways, as well as discussing the advances toward disease-targeted therapies for patients with glomerular disease.
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Affiliation(s)
- Christine Chew
- Faculty of Biology Medicine and Health, Wellcome Trust Centre for Cell-Matrix Research, Division of Cell Matrix Biology, School of Biological Sciences, University of Manchester, Manchester, United Kingdom
| | - Rachel Lennon
- Faculty of Biology Medicine and Health, Wellcome Trust Centre for Cell-Matrix Research, Division of Cell Matrix Biology, School of Biological Sciences, University of Manchester, Manchester, United Kingdom.,Department of Paediatric Nephrology, Royal Manchester Children's Hospital, Central Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, United Kingdom
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24
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Funk SD, Bayer RH, Malone AF, McKee KK, Yurchenco PD, Miner JH. Pathogenicity of a Human Laminin β2 Mutation Revealed in Models of Alport Syndrome. J Am Soc Nephrol 2017; 29:949-960. [PMID: 29263159 DOI: 10.1681/asn.2017090997] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2017] [Accepted: 11/19/2017] [Indexed: 01/15/2023] Open
Abstract
Pierson syndrome is a congenital nephrotic syndrome with eye and neurologic defects caused by mutations in laminin β2 (LAMB2), a major component of the glomerular basement membrane (GBM). Pathogenic missense mutations in human LAMB2 cluster in or near the laminin amino-terminal (LN) domain, a domain required for extracellular polymerization of laminin trimers and basement membrane scaffolding. Here, we investigated an LN domain missense mutation, LAMB2-S80R, which was discovered in a patient with Pierson syndrome and unusually late onset of proteinuria. Biochemical data indicated that this mutation impairs laminin polymerization, which we hypothesized to be the cause of the patient's nephrotic syndrome. Testing this hypothesis in genetically altered mice showed that the corresponding amino acid change (LAMB2-S83R) alone is not pathogenic. However, expression of LAMB2-S83R significantly increased the rate of progression to kidney failure in a Col4a3-/- mouse model of autosomal recessive Alport syndrome and increased proteinuria in Col4a5+/- females that exhibit a mild form of X-linked Alport syndrome due to mosaic deposition of collagen α3α4α5(IV) in the GBM. Collectively, these data show the pathogenicity of LAMB2-S80R and provide the first evidence of genetic modification of Alport phenotypes by variation in another GBM component. This finding could help explain the wide range of Alport syndrome onset and severity observed in patients with Alport syndrome, even for family members who share the same COL4 mutation. Our results also show the complexities of using model organisms to investigate genetic variants suspected of being pathogenic in humans.
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Affiliation(s)
- Steven D Funk
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri and
| | - Raymond H Bayer
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri and
| | - Andrew F Malone
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri and
| | - Karen K McKee
- Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey
| | - Peter D Yurchenco
- Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri and
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25
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Tabatabaeifar M, Wlodkowski T, Simic I, Denc H, Mollet G, Weber S, Moyers JJ, Brühl B, Randles MJ, Lennon R, Antignac C, Schaefer F. An inducible mouse model of podocin-mutation-related nephrotic syndrome. PLoS One 2017; 12:e0186574. [PMID: 29049388 PMCID: PMC5648285 DOI: 10.1371/journal.pone.0186574] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2017] [Accepted: 09/10/2017] [Indexed: 12/03/2022] Open
Abstract
Mutations in the NPHS2 gene, encoding podocin, cause hereditary nephrotic syndrome. The most common podocin mutation, R138Q, is associated with early disease onset and rapid progression to end-stage renal disease. Knock-in mice carrying a R140Q mutation, the mouse analogue of human R138Q, show developmental arrest of podocytes and lethal renal failure at neonatal age. Here we created a conditional podocin knock-in model named NPHS2R140Q/-, using a tamoxifen-inducible Cre recombinase, which permits to study the effects of the mutation in postnatal life. Within the first week of R140Q hemizygosity induction the animals developed proteinuria, which peaked after 4–5 weeks. Subsequently the animals developed progressive renal failure, with a median survival time of 12 (95% CI: 11–13) weeks. Foot process fusion was observed within one week, progressing to severe and global effacement in the course of the disease. The number of podocytes per glomerulus gradually diminished to 18% compared to healthy controls 12–16 weeks after induction. The fraction of segmentally sclerosed glomeruli was 25%, 85% and 97% at 2, 4 and 8 weeks, respectively. Severe tubulointerstitial fibrosis was present at later disease stage and was correlated quantitatively with the level of proteinuria at early disease stages. While R140Q podocin mRNA expression was elevated, protein abundance was reduced by more than 50% within one week following induction. Whereas miRNA21 expression persistently increased during the first 4 weeks, miRNA-193a expression peaked 2 weeks after induction. In conclusion, the inducible R140Q-podocin mouse model is an auspicious model of the most common genetic cause of human nephrotic syndrome, with a spontaneous disease course strongly reminiscent of the human disorder. This model constitutes a valuable tool to test the efficacy of novel pharmacological interventions aimed to improve podocyte function and viability and attenuate proteinuria, glomerulosclerosis and progressive renal failure.
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Affiliation(s)
- Mansoureh Tabatabaeifar
- Division of Pediatric Nephrology, Center for Pediatrics and Adolescent Medicine, University of Heidelberg, Heidelberg, Germany
| | - Tanja Wlodkowski
- Division of Pediatric Nephrology, Center for Pediatrics and Adolescent Medicine, University of Heidelberg, Heidelberg, Germany
| | - Ivana Simic
- Division of Pediatric Nephrology, Center for Pediatrics and Adolescent Medicine, University of Heidelberg, Heidelberg, Germany
| | - Helga Denc
- Division of Pediatric Nephrology, Center for Pediatrics and Adolescent Medicine, University of Heidelberg, Heidelberg, Germany
| | - Geraldine Mollet
- INSERM, U1163, Imagine Institute, Laboratory of Hereditary Kidney Diseases, Paris, France
- Paris Descartes-Sorbonne Paris Cité University, Paris, France
| | - Stefanie Weber
- Pediatric Nephrology, Center for Pediatrics and Adolescent Medicine, Philipps-University Marburg, Marburg, Germany
| | | | - Barbara Brühl
- Institute for Anatomy and Cell Biology, University of Heidelberg, Heidelberg, Germany
| | - Michael Joseph Randles
- Wellcome Trust Centre for Cell Matrix Research, University of Manchester, Manchester, United Kingdom
- Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Rachel Lennon
- Wellcome Trust Centre for Cell Matrix Research, University of Manchester, Manchester, United Kingdom
- Faculty of Biology Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Corinne Antignac
- INSERM, U1163, Imagine Institute, Laboratory of Hereditary Kidney Diseases, Paris, France
- Paris Descartes-Sorbonne Paris Cité University, Paris, France
- Department of Genetics, Necker Hospital, Assistance Publique—Hôpitaux de Paris, Paris, France
| | - Franz Schaefer
- Division of Pediatric Nephrology, Center for Pediatrics and Adolescent Medicine, University of Heidelberg, Heidelberg, Germany
- * E-mail:
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26
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Suleiman HY, Roth R, Jain S, Heuser JE, Shaw AS, Miner JH. Injury-induced actin cytoskeleton reorganization in podocytes revealed by super-resolution microscopy. JCI Insight 2017; 2:94137. [PMID: 28814668 DOI: 10.1172/jci.insight.94137] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 07/07/2017] [Indexed: 02/06/2023] Open
Abstract
The architectural integrity of tissues requires complex interactions, both between cells and between cells and the extracellular matrix. Fundamental to cell and tissue homeostasis are the specific mechanical forces conveyed by the actomyosin cytoskeleton. Here we used super-resolution imaging methods to visualize the actin cytoskeleton in the kidney glomerulus, an organized collection of capillaries that filters the blood to make the primary urine. Our analysis of both mouse and human glomeruli reveals a network of myosin IIA-containing contractile actin cables within podocyte cell bodies and major processes at the outer aspects of the glomerular tuft. These likely exert force on an underlying network of myosin IIA-negative, noncontractile actin fibers present within podocyte foot processes that function to both anchor the cells to the glomerular basement membrane and stabilize the slit diaphragm against the pressure of fluid flow. After injuries that disrupt the kidney filtration barrier and cause foot process effacement, the podocyte's contractile actomyosin network relocates to the basolateral surface of the cell, manifesting as sarcomere-like structures juxtaposed to the basement membrane. Our findings suggest a new model of the podocyte actin cytoskeleton in health and disease and suggest the existence of novel mechanisms that regulate podocyte architecture.
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Affiliation(s)
- Hani Y Suleiman
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Robyn Roth
- Washington University Center for Cellular Imaging, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Sanjay Jain
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - John E Heuser
- Institute for Integrated Cell-Material Sciences (iCeMS), Kyoto University, Kyoto, Japan
| | | | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
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27
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Kino J, Tsukaguchi H, Kimata T, Nguyen HT, Nakano Y, Miyake N, Matsumoto N, Kaneko K. Nephron development and extrarenal features in a child with congenital nephrotic syndrome caused by null LAMB2 mutations. BMC Nephrol 2017; 18:220. [PMID: 28683731 PMCID: PMC5501564 DOI: 10.1186/s12882-017-0632-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Accepted: 06/22/2017] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Congenital nephrotic syndrome (CNS) is a rare disorder caused by various structural and developmental defects of glomeruli. It occurs typically as an isolated kidney disorder but associates sometimes with other systemic, extrarenal manifestations. CASE PRESENTATIONS An infant presented with severe CNS, which progressed rapidly to renal failure at age of 3 months and death at 27 months. The clinical phenotypes and genetic causes were studied, including the renal pathology at autopsy. Besides the CNS, the affected child had remarkable right-side predominant eye-ball hypoplasia with bilateral anterior chamber dysgenesis (microcoria). Brain MRI revealed grossly normal development in the cerebrum, cerebellum, and brain stem. Auditory brainstem responses were bilaterally blunted, suggesting a defective auditory system. At autopsy, both kidneys were mildly atrophied with persistent fetal lobulation. Microscopic examination showed a diffuse global sclerosis. However, despite of the smaller size of glomeruli, the nephron number remained similar to that of the age-matched control. Whole-exome sequencing revealed that the affected child was compound heterozygous for novel truncating LAMB2 mutations: a 4-bp insertion (p.Gly1693Alafs*8) and a splicing donor-site substitution (c.1225 + 1G > A), presumably deleting the coiled-coil domains that form the laminin 5-2-1 heterotrimer complex. CONCLUSIONS Our case represents a variation of Pierson syndrome that accompanies CNS with unilateral ocular hypoplasia. The average number but smaller glomeruli could reflect either mal-development or glomerulosclerosis. Heterogeneous clinical expression of LAMB2 defects may associate with the difference in fetal β1 subtype compensation among affected tissues. Further study is necessary to evaluate incidence and features of auditory defect under LAMB2 deficiency.
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Affiliation(s)
- Jiro Kino
- Department of Pediatrics, Kansai Medical University, 2-5-1 Shimachi, Hirakata, Osaka, 573-1010, Japan
| | - Hiroyasu Tsukaguchi
- Second Department of Internal Medicine, Kansai Medical University, 2-5-1 Shinmachi Hirakata, Osaka, 573-1010, Japan.
| | - Takahisa Kimata
- Department of Pediatrics, Kansai Medical University, 2-5-1 Shimachi, Hirakata, Osaka, 573-1010, Japan
| | - Huan Thanh Nguyen
- Second Department of Internal Medicine, Kansai Medical University, 2-5-1 Shinmachi Hirakata, Osaka, 573-1010, Japan
| | - Yorika Nakano
- Department of Pathology and Laboratory Medicine, Kansai Medical University, Osaka, Japan.,Present Address: Department of Histopathology and Cytology, Japanese Red Cross Kyoto Daini Hospital, Kyoto, Japan
| | - Noriko Miyake
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, 236-0004, Japan
| | - Naomichi Matsumoto
- Department of Human Genetics, Yokohama City University Graduate School of Medicine, 3-9 Fukuura, Kanazawa-ku, Yokohama, 236-0004, Japan
| | - Kazunari Kaneko
- Department of Pediatrics, Kansai Medical University, 2-5-1 Shimachi, Hirakata, Osaka, 573-1010, Japan
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28
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Tachmazidou I, Süveges D, Min JL, Ritchie GRS, Steinberg J, Walter K, Iotchkova V, Schwartzentruber J, Huang J, Memari Y, McCarthy S, Crawford AA, Bombieri C, Cocca M, Farmaki AE, Gaunt TR, Jousilahti P, Kooijman MN, Lehne B, Malerba G, Männistö S, Matchan A, Medina-Gomez C, Metrustry SJ, Nag A, Ntalla I, Paternoster L, Rayner NW, Sala C, Scott WR, Shihab HA, Southam L, St Pourcain B, Traglia M, Trajanoska K, Zaza G, Zhang W, Artigas MS, Bansal N, Benn M, Chen Z, Danecek P, Lin WY, Locke A, Luan J, Manning AK, Mulas A, Sidore C, Tybjaerg-Hansen A, Varbo A, Zoledziewska M, Finan C, Hatzikotoulas K, Hendricks AE, Kemp JP, Moayyeri A, Panoutsopoulou K, Szpak M, Wilson SG, Boehnke M, Cucca F, Di Angelantonio E, Langenberg C, Lindgren C, McCarthy MI, Morris AP, Nordestgaard BG, Scott RA, Tobin MD, Wareham NJ, Burton P, Chambers JC, Smith GD, Dedoussis G, Felix JF, Franco OH, Gambaro G, Gasparini P, Hammond CJ, Hofman A, Jaddoe VWV, Kleber M, Kooner JS, Perola M, Relton C, Ring SM, Rivadeneira F, Salomaa V, Spector TD, Stegle O, Toniolo D, Uitterlinden AG, Barroso I, Greenwood CMT, Perry JRB, Walker BR, Butterworth AS, Xue Y, Durbin R, Small KS, Soranzo N, Timpson NJ, Zeggini E. Whole-Genome Sequencing Coupled to Imputation Discovers Genetic Signals for Anthropometric Traits. Am J Hum Genet 2017; 100:865-884. [PMID: 28552196 PMCID: PMC5473732 DOI: 10.1016/j.ajhg.2017.04.014] [Citation(s) in RCA: 103] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2016] [Accepted: 04/21/2017] [Indexed: 01/05/2023] Open
Abstract
Deep sequence-based imputation can enhance the discovery power of genome-wide association studies by assessing previously unexplored variation across the common- and low-frequency spectra. We applied a hybrid whole-genome sequencing (WGS) and deep imputation approach to examine the broader allelic architecture of 12 anthropometric traits associated with height, body mass, and fat distribution in up to 267,616 individuals. We report 106 genome-wide significant signals that have not been previously identified, including 9 low-frequency variants pointing to functional candidates. Of the 106 signals, 6 are in genomic regions that have not been implicated with related traits before, 28 are independent signals at previously reported regions, and 72 represent previously reported signals for a different anthropometric trait. 71% of signals reside within genes and fine mapping resolves 23 signals to one or two likely causal variants. We confirm genetic overlap between human monogenic and polygenic anthropometric traits and find signal enrichment in cis expression QTLs in relevant tissues. Our results highlight the potential of WGS strategies to enhance biologically relevant discoveries across the frequency spectrum.
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Affiliation(s)
- Ioanna Tachmazidou
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK
| | - Dániel Süveges
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK
| | - Josine L Min
- MRC Integrative Epidemiology Unit, School of Social and Community Medicine, University of Bristol, Bristol BS8 2BN, UK
| | - Graham R S Ritchie
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK; Usher Institute of Population Health Sciences & Informatics, University of Edinburgh, Edinburgh EH16 4UX, UK; MRC Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH16 4UX, UK
| | - Julia Steinberg
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK
| | - Klaudia Walter
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK
| | - Valentina Iotchkova
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK; European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SD, UK
| | | | - Jie Huang
- Boston VA Research Institute, Boston, MA 02130, USA
| | - Yasin Memari
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK
| | - Shane McCarthy
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK
| | - Andrew A Crawford
- MRC Integrative Epidemiology Unit, School of Social and Community Medicine, University of Bristol, Bristol BS8 2BN, UK; BHF Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, Edinburgh EH16 4TJ, UK
| | - Cristina Bombieri
- Department of Neurological, Biomedical and Movement Sciences, University of Verona, Verona 37134, Italy
| | - Massimiliano Cocca
- Department of Medical, Surgical and Health Sciences, University of Trieste, Trieste 34100, Italy
| | - Aliki-Eleni Farmaki
- Department of Nutrition and Dietetics, School of Health Science and Education, Harokopio University, Athens 17671, Greece
| | - Tom R Gaunt
- MRC Integrative Epidemiology Unit, School of Social and Community Medicine, University of Bristol, Bristol BS8 2BN, UK
| | - Pekka Jousilahti
- Department of Health, National Institute for Health and Welfare, Helsinki 00271, Finland
| | - Marjolein N Kooijman
- The Generation R Study Group, Erasmus Medical Center, University Medical Center, Rotterdam 3000 CA, the Netherlands; Department of Epidemiology, Erasmus Medical Center, University Medical Center, Rotterdam 3000 CA, the Netherlands; Department of Pediatrics, Erasmus Medical Center, University Medical Center, Rotterdam 3000 CA, the Netherlands
| | - Benjamin Lehne
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London W2 1PG, UK
| | - Giovanni Malerba
- Department of Neurological, Biomedical and Movement Sciences, University of Verona, Verona 37134, Italy
| | - Satu Männistö
- Department of Health, National Institute for Health and Welfare, Helsinki 00271, Finland
| | - Angela Matchan
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK
| | - Carolina Medina-Gomez
- Department of Epidemiology, Erasmus Medical Center, University Medical Center, Rotterdam 3000 CA, the Netherlands; Department of Internal Medicine, Erasmus Medical Center, University Medical Center, Rotterdam 3000 CA, the Netherlands
| | - Sarah J Metrustry
- Department of Twin Research and Genetic Epidemiology, King's College London, London SE1 7EH, UK
| | - Abhishek Nag
- Department of Twin Research and Genetic Epidemiology, King's College London, London SE1 7EH, UK
| | - Ioanna Ntalla
- William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, London EC1M 6BQ, UK
| | - Lavinia Paternoster
- MRC Integrative Epidemiology Unit, School of Social and Community Medicine, University of Bristol, Bristol BS8 2BN, UK
| | - Nigel W Rayner
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK; Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford OX3 7LJ, UK
| | - Cinzia Sala
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan 20132, Italy
| | - William R Scott
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London W2 1PG, UK; Department of Cardiology, Ealing Hospital NHS Trust, Middlesex UB1 3EU, UK
| | - Hashem A Shihab
- MRC Integrative Epidemiology Unit, School of Social and Community Medicine, University of Bristol, Bristol BS8 2BN, UK
| | - Lorraine Southam
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK; Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK
| | - Beate St Pourcain
- MRC Integrative Epidemiology Unit, School of Social and Community Medicine, University of Bristol, Bristol BS8 2BN, UK; Max Planck Institute for Psycholinguistics, Nijmegen 6500, the Netherlands
| | - Michela Traglia
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan 20132, Italy
| | - Katerina Trajanoska
- Department of Epidemiology, Erasmus Medical Center, University Medical Center, Rotterdam 3000 CA, the Netherlands; Department of Internal Medicine, Erasmus Medical Center, University Medical Center, Rotterdam 3000 CA, the Netherlands
| | - Gialuigi Zaza
- Renal Unit, Department of Medicine, Verona University Hospital, Verona 37126, Italy
| | - Weihua Zhang
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London W2 1PG, UK; Department of Cardiology, Ealing Hospital NHS Trust, Middlesex UB1 3EU, UK
| | - María S Artigas
- Genetic Epidemiology Group, Department of Health Sciences, University of Leicester, Leicester LE1 7RH, UK
| | - Narinder Bansal
- Cardiovascular Epidemiology Unit, Department of Public Health & Primary Care, University of Cambridge, Cambridge CB1 8RN, UK
| | - Marianne Benn
- Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark; Department of Clinical Biochemistry, Rigshospitalet, Copenhagen University Hospital, Copenhagen 2100, Denmark
| | - Zhongsheng Chen
- Department of Biostatistics and Center for Statistical Genetics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Petr Danecek
- Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark; Department of Clinical Biochemistry, Rigshospitalet, Copenhagen University Hospital, Copenhagen 2100, Denmark
| | - Wei-Yu Lin
- Cardiovascular Epidemiology Unit, Department of Public Health & Primary Care, University of Cambridge, Cambridge CB1 8RN, UK
| | - Adam Locke
- Department of Biostatistics and Center for Statistical Genetics, University of Michigan, Ann Arbor, MI 48109, USA; McDonnell Genome Institute, Washington University School of Medicine, Saint Louis, MO 63108, USA
| | - Jian'an Luan
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Alisa K Manning
- Center for Human Genetics Research, Massachusetts General Hospital, Boston, MA 02114, USA; Program in Medical and Population Genetics, Broad Institute, Cambridge, MA 02142, USA; Department of Medicine, Harvard University Medical School, Boston, MA 02115, USA
| | - Antonella Mulas
- Istituto di Ricerca Genetica e Biomedica (IRGB-CNR), Cagliari 09100, Italy; Università degli Studi di Sassari, Sassari 07100, Italy
| | - Carlo Sidore
- Istituto di Ricerca Genetica e Biomedica (IRGB-CNR), Cagliari 09100, Italy
| | - Anne Tybjaerg-Hansen
- Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark; Department of Clinical Biochemistry, Rigshospitalet, Copenhagen University Hospital, Copenhagen 2100, Denmark
| | - Anette Varbo
- Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark; Department of Clinical Biochemistry, Rigshospitalet, Copenhagen University Hospital, Copenhagen 2100, Denmark
| | | | - Chris Finan
- Institute of Cardiovascular Science, Faculty of Population Health, University College London, London WC1E 6BT, UK
| | | | - Audrey E Hendricks
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK; Mathematical and Statistical Sciences, University of Colorado Denver, Denver, CO 80204, USA
| | - John P Kemp
- MRC Integrative Epidemiology Unit, School of Social and Community Medicine, University of Bristol, Bristol BS8 2BN, UK; University of Queensland Diamantina Institute, Translational Research Institute, Brisbane, QLD 4072, Australia
| | - Alireza Moayyeri
- Department of Twin Research and Genetic Epidemiology, King's College London, London SE1 7EH, UK; Institute of Health Informatics, University College London, London NW1 2DA, UK
| | | | - Michal Szpak
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK
| | - Scott G Wilson
- Department of Twin Research and Genetic Epidemiology, King's College London, London SE1 7EH, UK; School of Medicine and Pharmacology, The University of Western Australia, Crawley, WA 6009, Australia; Department of Endocrinology and Diabetes, Sir Charles Gairdner Hospital, Nedlands, WA 6009, Australia
| | - Michael Boehnke
- Department of Biostatistics and Center for Statistical Genetics, University of Michigan, Ann Arbor, MI 48109, USA
| | - Francesco Cucca
- Istituto di Ricerca Genetica e Biomedica (IRGB-CNR), Cagliari 09100, Italy; Università degli Studi di Sassari, Sassari 07100, Italy
| | - Emanuele Di Angelantonio
- Cardiovascular Epidemiology Unit, Department of Public Health & Primary Care, University of Cambridge, Cambridge CB1 8RN, UK; The National Institute for Health Research Blood and Transplant Unit (NIHR BTRU) in Donor Health and Genomics at the University of Cambridge, Cambridge CB1 8RN, UK
| | - Claudia Langenberg
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Cecilia Lindgren
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; Li Ka Shing Centre for Health Information and Discovery, The Big Data Institute, University of Oxford, Oxford OX3 7BN, UK
| | - Mark I McCarthy
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; Oxford Centre for Diabetes, Endocrinology and Metabolism, University of Oxford, Churchill Hospital, Oxford OX3 7LJ, UK; Oxford NIHR Biomedical Research Centre, Churchill Hospital, Oxford OX3 7LJ, UK
| | - Andrew P Morris
- Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; Department of Biostatistics, University of Liverpool, Liverpool L69 3GL, UK; Estonian Genome Center, University of Tartu, Tartu, Tartumaa 51010, Estonia
| | - Børge G Nordestgaard
- Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen 2200, Denmark; Department of Clinical Biochemistry, Rigshospitalet, Copenhagen University Hospital, Copenhagen 2100, Denmark
| | - Robert A Scott
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Martin D Tobin
- Genetic Epidemiology Group, Department of Health Sciences, University of Leicester, Leicester LE1 7RH, UK; National Institute for Health Research (NIHR) Leicester Respiratory Biomedical Research Unit, Glenfield Hospital, Leicester LE3 9QP, UK
| | - Nicholas J Wareham
- MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | | | | | - Paul Burton
- D2K Research Group, School of Social and Community Medicine, University of Bristol, Bristol BS8 2BN, UK
| | - John C Chambers
- Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, London W2 1PG, UK; Department of Cardiology, Ealing Hospital NHS Trust, Middlesex UB1 3EU, UK; Imperial College Healthcare NHS Trust, London W2 1NY, UK
| | - George Davey Smith
- MRC Integrative Epidemiology Unit, School of Social and Community Medicine, University of Bristol, Bristol BS8 2BN, UK
| | - George Dedoussis
- Department of Nutrition and Dietetics, School of Health Science and Education, Harokopio University, Athens 17671, Greece
| | - Janine F Felix
- The Generation R Study Group, Erasmus Medical Center, University Medical Center, Rotterdam 3000 CA, the Netherlands; Department of Epidemiology, Erasmus Medical Center, University Medical Center, Rotterdam 3000 CA, the Netherlands; Department of Pediatrics, Erasmus Medical Center, University Medical Center, Rotterdam 3000 CA, the Netherlands
| | - Oscar H Franco
- Department of Epidemiology, Erasmus Medical Center, University Medical Center, Rotterdam 3000 CA, the Netherlands
| | - Giovanni Gambaro
- Division of Nephrology and Dialysis, Columbus-Gemelli University Hospital, Catholic University, Rome 00168, Italy
| | - Paolo Gasparini
- Department of Medical, Surgical and Health Sciences, University of Trieste, Trieste 34100, Italy; Medical Genetics, Institute for Maternal and Child Health IRCCS "Burlo Garofolo", Trieste 34100, Italy
| | - Christopher J Hammond
- Department of Twin Research and Genetic Epidemiology, King's College London, London SE1 7EH, UK
| | - Albert Hofman
- Department of Epidemiology, Erasmus Medical Center, University Medical Center, Rotterdam 3000 CA, the Netherlands
| | - Vincent W V Jaddoe
- The Generation R Study Group, Erasmus Medical Center, University Medical Center, Rotterdam 3000 CA, the Netherlands; Department of Epidemiology, Erasmus Medical Center, University Medical Center, Rotterdam 3000 CA, the Netherlands; Department of Pediatrics, Erasmus Medical Center, University Medical Center, Rotterdam 3000 CA, the Netherlands
| | - Marcus Kleber
- Vth Department of Medicine, Medical Faculty Mannheim, Heidelberg University, Mannheim 68167, Germany
| | - Jaspal S Kooner
- Department of Cardiology, Ealing Hospital NHS Trust, Middlesex UB1 3EU, UK; Imperial College Healthcare NHS Trust, London W2 1NY, UK; National Heart and Lung Institute, Imperial College London, Hammersmith Hospital Campus, London W12 0NN, UK
| | - Markus Perola
- Department of Health, National Institute for Health and Welfare, Helsinki 00271, Finland; Estonian Genome Center, University of Tartu, Tartu, Tartumaa 51010, Estonia; Institute for Molecular Medicine (FIMM), University of Helsinki, Helsinki 00290, Finland
| | - Caroline Relton
- MRC Integrative Epidemiology Unit, School of Social and Community Medicine, University of Bristol, Bristol BS8 2BN, UK
| | - Susan M Ring
- MRC Integrative Epidemiology Unit, School of Social and Community Medicine, University of Bristol, Bristol BS8 2BN, UK
| | - Fernando Rivadeneira
- Department of Epidemiology, Erasmus Medical Center, University Medical Center, Rotterdam 3000 CA, the Netherlands; Department of Internal Medicine, Erasmus Medical Center, University Medical Center, Rotterdam 3000 CA, the Netherlands
| | - Veikko Salomaa
- Department of Health, National Institute for Health and Welfare, Helsinki 00271, Finland
| | - Timothy D Spector
- Department of Twin Research and Genetic Epidemiology, King's College London, London SE1 7EH, UK
| | - Oliver Stegle
- European Molecular Biology Laboratory, European Bioinformatics Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SD, UK
| | - Daniela Toniolo
- Division of Genetics and Cell Biology, San Raffaele Scientific Institute, Milan 20132, Italy
| | - André G Uitterlinden
- Department of Epidemiology, Erasmus Medical Center, University Medical Center, Rotterdam 3000 CA, the Netherlands; Department of Internal Medicine, Erasmus Medical Center, University Medical Center, Rotterdam 3000 CA, the Netherlands
| | | | | | | | - Inês Barroso
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK; University of Cambridge Metabolic Research Laboratories, and NIHR Cambridge Biomedical Research Centre, Wellcome Trust-MRC Institute of Metabolic Science, Addenbrooke's Hospital, Cambridge CB2 0QQ, UK
| | - Celia M T Greenwood
- Lady Davis Institute for Medical Research, Jewish General Hospital, Montréal, QC H3T 1E2, Canada; Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montréal, QC H3A 1A2, Canada; Department of Oncology, McGill University, Montréal, QC H2W 1S6, Canada
| | - John R B Perry
- Department of Twin Research and Genetic Epidemiology, King's College London, London SE1 7EH, UK; MRC Epidemiology Unit, University of Cambridge School of Clinical Medicine, Cambridge CB2 0QQ, UK
| | - Brian R Walker
- BHF Centre for Cardiovascular Science, Queen's Medical Research Institute, University of Edinburgh, Edinburgh EH16 4TJ, UK
| | - Adam S Butterworth
- Cardiovascular Epidemiology Unit, Department of Public Health & Primary Care, University of Cambridge, Cambridge CB1 8RN, UK; The National Institute for Health Research Blood and Transplant Unit (NIHR BTRU) in Donor Health and Genomics at the University of Cambridge, Cambridge CB1 8RN, UK
| | - Yali Xue
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK
| | - Richard Durbin
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK
| | - Kerrin S Small
- Department of Twin Research and Genetic Epidemiology, King's College London, London SE1 7EH, UK
| | - Nicole Soranzo
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK; The National Institute for Health Research Blood and Transplant Unit (NIHR BTRU) in Donor Health and Genomics at the University of Cambridge, Cambridge CB1 8RN, UK; Department of Haematology, University of Cambridge, Cambridge CB2 0AH, UK
| | - Nicholas J Timpson
- MRC Integrative Epidemiology Unit, School of Social and Community Medicine, University of Bristol, Bristol BS8 2BN, UK
| | - Eleftheria Zeggini
- The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton CB10 1SA, UK.
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Yao Y. Laminin: loss-of-function studies. Cell Mol Life Sci 2017; 74:1095-1115. [PMID: 27696112 PMCID: PMC11107706 DOI: 10.1007/s00018-016-2381-0] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 09/25/2016] [Accepted: 09/26/2016] [Indexed: 01/13/2023]
Abstract
Laminin, one of the most widely expressed extracellular matrix proteins, exerts many important functions in multiple organs/systems and at various developmental stages. Although its critical roles in embryonic development have been demonstrated, laminin's functions at later stages remain largely unknown, mainly due to its intrinsic complexity and lack of research tools (most laminin mutants are embryonic lethal). With the advance of genetic and molecular techniques, many new laminin mutants have been generated recently. These new mutants usually have a longer lifespan and show previously unidentified phenotypes. Not only do these studies suggest novel functions of laminin, but also they provide invaluable animal models that allow investigation of laminin's functions at late stages. Here, I first briefly introduce the nomenclature, structure, and biochemistry of laminin in general. Next, all the loss-of-function mutants/models for each laminin chain are discussed and their phenotypes compared. I hope to provide a comprehensive review on laminin functions and its loss-of-function models, which could serve as a reference for future research in this understudied field.
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Affiliation(s)
- Yao Yao
- College of Pharmacy, University of Minnesota, Duluth, MN, 55812, USA.
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Permeation of macromolecules into the renal glomerular basement membrane and capture by the tubules. Proc Natl Acad Sci U S A 2017; 114:2958-2963. [PMID: 28246329 PMCID: PMC5358373 DOI: 10.1073/pnas.1616457114] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Human kidneys contain ∼2 x 106 glomeruli that produce ∼180 L per day of primary filtrate. Downstream tubules reabsorb most of the water, salt, and desirable low-molecular weight substances, leaving 1 to 2 L per day of urine containing undesirable waste products. Currently, most investigators think that the primary filtrate is low in protein because fluid exiting the glomerulus passes through slits spanned by a diaphragm that acts as a low-porosity molecular sieve. Our experiments challenge this view; they show that size-dependent permeation into the glomerular basement membrane and into a gel-like coat that covers the slits, together with saturable tubular reabsorption, determines which macromolecules reach the urine. The slit diaphragm is essential for capillary structure but may not directly determine glomerular size selectivity. How the kidney prevents urinary excretion of plasma proteins continues to be debated. Here, using unfixed whole-mount mouse kidneys, we show that fluorescent-tagged proteins and neutral dextrans permeate into the glomerular basement membrane (GBM), in general agreement with Ogston's 1958 equation describing how permeation into gels is related to molecular size. Electron-microscopic analyses of kidneys fixed seconds to hours after injecting gold-tagged albumin, negatively charged gold nanoparticles, and stable oligoclusters of gold nanoparticles show that permeation into the lamina densa of the GBM is size-sensitive. Nanoparticles comparable in size with IgG dimers do not permeate into it. IgG monomer-sized particles permeate to some extent. Albumin-sized particles permeate extensively into the lamina densa. Particles traversing the lamina densa tend to accumulate upstream of the podocyte glycocalyx that spans the slit, but none are observed upstream of the slit diaphragm. At low concentrations, ovalbumin-sized nanoparticles reach the primary filtrate, are captured by proximal tubule cells, and are endocytosed. At higher concentrations, tubular capture is saturated, and they reach the urine. In mouse models of Pierson’s or Alport’s proteinuric syndromes resulting from defects in GBM structural proteins (laminin β2 or collagen α3 IV), the GBM is irregularly swollen, the lamina densa is absent, and permeation is increased. Our observations indicate that size-dependent permeation into the lamina densa of the GBM and the podocyte glycocalyx, together with saturable tubular capture, determines which macromolecules reach the urine without the need to invoke direct size selection by the slit diaphragm.
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LeBleu VS, Macdonald B, Kalluri R. Structure and Function of Basement Membranes. Exp Biol Med (Maywood) 2016; 232:1121-9. [PMID: 17895520 DOI: 10.3181/0703-mr-72] [Citation(s) in RCA: 364] [Impact Index Per Article: 45.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Basement membranes (BMs) are present in every tissue of the human body. All epithelium and endothelium is in direct association with BMs. BMs are a composite of several large glycoproteins and form an organized scaffold to provide structural support to the tissue and also offer functional input to modulate cellular function. While collagen I is the most abundant protein in the human body, type IV collagen is the most abundant protein in BMs. Matrigel is commonly used as surrogate for BMs in many experiments, but this is a tumor-derived BM–like material and does not contain all of the components that natural BMs possess. The structure of BMs and their functional role in tissues are unique and unlike any other class of proteins in the human body. Increasing evidence suggests that BMs are unique signal input devices that likely fine tune cellular function. Additionally, the resulting endothelial and epithelial heterogeneity in human body is a direct contribution of cell-matrix interaction facilitated by the diverse compositions of BMs.
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Affiliation(s)
- Valerie S LeBleu
- Division of Matrix Biology, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts 02215, USA
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Abstract
PURPOSE OF REVIEW In this review, we take a combined membrane biologist's and geneticist's view of the podocyte, to examine how genetics have informed our understanding of membrane receptors, channels, and other signaling molecules affecting podocyte health and disease. RECENT FINDINGS An integral part of the kidney, the glomerulus, is responsible for the kidney's filter function. Within the glomerulus, the podocyte is a unique cell serving a critically important role: it is exposed to signals from the urinary space in Bowman's capsule, it receives and transmits signals to/from the basement membrane upon which it elaborates, and it receives signals from the vascular space with which it also communicates, thus exposed to toxins, viruses, chemicals, proteins, and cellular components or debris that flow in the blood stream. Our understanding of how podocytes perform their important role has been largely informed by human genetics, and the recent revolution afforded by exome sequencing has brought a tremendous wealth of new genetic data to light. SUMMARY Genetically defined, rare/orphan podocytopathies, as reviewed here, are critically important to study as they may reveal the next generation targets for precision medicine in nephrology.
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Rogers RS, Nishimune H. The role of laminins in the organization and function of neuromuscular junctions. Matrix Biol 2016; 57-58:86-105. [PMID: 27614294 DOI: 10.1016/j.matbio.2016.08.008] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 08/10/2016] [Accepted: 08/17/2016] [Indexed: 01/11/2023]
Abstract
The synapse between motor neurons and skeletal muscle is known as the neuromuscular junction (NMJ). Proper alignment of presynaptic and post-synaptic structures of motor neurons and muscle fibers, respectively, is essential for efficient motor control of skeletal muscles. The synaptic cleft between these two cells is filled with basal lamina. Laminins are heterotrimer extracellular matrix molecules that are key members of the basal lamina. Laminin α4, α5, and β2 chains specifically localize to NMJs, and these laminin isoforms play a critical role in maintenance of NMJs and organization of synaptic vesicle release sites known as active zones. These individual laminin chains exert their role in organizing NMJs by binding to their receptors including integrins, dystroglycan, and voltage-gated calcium channels (VGCCs). Disruption of these laminins or the laminin-receptor interaction occurs in neuromuscular diseases including Pierson syndrome and Lambert-Eaton myasthenic syndrome (LEMS). Interventions to maintain proper level of laminins and their receptor interactions may be insightful in treating neuromuscular diseases and aging related degeneration of NMJs.
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Affiliation(s)
- Robert S Rogers
- Department of Anatomy and Cell Biology, University of Kansas School of Medicine, Kansas City, Kansas, USA.
| | - Hiroshi Nishimune
- Department of Anatomy and Cell Biology, University of Kansas School of Medicine, Kansas City, Kansas, USA.
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Monteiro MM, D'Epiro TTS, Bernardi L, Fossati ACM, Santos MFD, Lamers ML. Long- and short-term diabetes mellitus type 1 modify young and elder rat salivary glands morphology. Arch Oral Biol 2016; 73:40-47. [PMID: 27664563 DOI: 10.1016/j.archoralbio.2016.08.028] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 08/22/2016] [Accepted: 08/24/2016] [Indexed: 10/21/2022]
Abstract
OBJECTIVE In this study we performed a temporal analysis of the effects of Diabetes Mellitus on morphology and laminin deposition in salivary glands of young (2 months-old) and aging (12 months-old) male Wistar rats, using immunohistochemistry. MATERIALS AND METHODS The animals were divided in control and diabetic (Streptozotocin induced) groups and euthanized after short and long-term diabetes induction. RESULTS Short-term induction led to vacuolization of parotid acinar cells and increased laminin deposition in both animal ages. In young rats, no difference was observed between short or long-term diabetes regarding laminin deposition, but parotid acinar cells vacuolization was more discrete after long-term diabetes. A slight decrease of submandibular gland convoluted granular ducts was observed in young and elder diabetic animal ages. In diabetic aging rats was observed an increase of laminin content only in the parotid gland. CONCLUSIONS These results suggest that some Diabetes Mellitus effects on salivary glands are not progressive over time, possibly due to the existence of adaptive mechanisms in response to chronic hyperglycemia. They also show that the duration of the disease was more relevant to the morphological effects than the age, although it is known that aging per se affects salivary gland morphology and function.
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Affiliation(s)
- Mariana Mirim Monteiro
- Cell and Developmental Biology Department, Institute of Biomedical Sciences, University of São Paulo, Brazil
| | | | - Lisiane Bernardi
- Department of Morphological Sciences, Institute of Basic Health Sciences, Federal University of Rio Grande do Sul, Brazil
| | | | | | - Marcelo Lazzaron Lamers
- Cell and Developmental Biology Department, Institute of Biomedical Sciences, University of São Paulo, Brazil; Department of Morphological Sciences, Institute of Basic Health Sciences, Federal University of Rio Grande do Sul, Brazil.
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35
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Marshall CB. Rethinking glomerular basement membrane thickening in diabetic nephropathy: adaptive or pathogenic? Am J Physiol Renal Physiol 2016; 311:F831-F843. [PMID: 27582102 DOI: 10.1152/ajprenal.00313.2016] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2016] [Accepted: 08/21/2016] [Indexed: 12/12/2022] Open
Abstract
Diabetic nephropathy (DN) is the leading cause of chronic kidney disease in the United States and is a major cause of cardiovascular disease and death. DN develops insidiously over a span of years before clinical manifestations, including microalbuminuria and declining glomerular filtration rate (GFR), are evident. During the clinically silent period, structural lesions develop, including glomerular basement membrane (GBM) thickening, mesangial expansion, and glomerulosclerosis. Once microalbuminuria is clinically apparent, structural lesions are often considerably advanced, and GFR decline may then proceed rapidly toward end-stage kidney disease. Given the current lack of sensitive biomarkers for detecting early DN, a shift in focus toward examining the cellular and molecular basis for the earliest structural change in DN, i.e., GBM thickening, may be warranted. Observed within one to two years following the onset of diabetes, GBM thickening precedes clinically evident albuminuria. In the mature glomerulus, the podocyte is likely key in modifying the GBM, synthesizing and assembling matrix components, both in physiological and pathological states. Podocytes also secrete matrix metalloproteinases, crucial mediators in extracellular matrix turnover. Studies have shown that the critical podocyte-GBM interface is disrupted in the diabetic milieu. Just as healthy podocytes are essential for maintaining the normal GBM structure and function, injured podocytes likely have a fundamental role in upsetting the balance between the GBM's synthetic and degradative pathways. This article will explore the biological significance of GBM thickening in DN by reviewing what is known about the GBM's formation, its maintenance during health, and its disruption in DN.
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Affiliation(s)
- Caroline B Marshall
- Division of Nephrology, Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama; and Department of Veterans Affairs Medical Center, Birmingham, Alabama
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36
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Autoimmunity against laminins. Clin Immunol 2016; 170:39-52. [PMID: 27464450 DOI: 10.1016/j.clim.2016.07.021] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 04/30/2016] [Accepted: 07/22/2016] [Indexed: 12/12/2022]
Abstract
Laminins are ubiquitous constituents of the basement membranes with major architectural and functional role as supported by the fact that absence or mutations of laminins lead to either lethal or severely impairing phenotypes. Besides genetic defects, laminins are involved in a wide range of human diseases including cancer, infections, and inflammatory diseases, as well as autoimmune disorders. A growing body of evidence implicates several laminin chains as autoantigens in blistering skin diseases, collagenoses, vasculitis, or post-infectious autoimmunity. The current paper reviews the existing knowledge on autoimmunity against laminins referring to both experimental and clinical data, and on therapeutic implications of anti-laminin antibodies. Further investigation of relevant laminin epitopes in pathogenic autoimmunity would facilitate the development of appropriate diagnostic tools for thorough characterization of patients' antibody specificities and should decisively contribute to designing more specific therapeutic interventions.
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Abstract
Podocytes are highly specialized cells of the kidney glomerulus that wrap around capillaries and that neighbor cells of the Bowman’s capsule. When it comes to glomerular filtration, podocytes play an active role in preventing plasma proteins from entering the urinary ultrafiltrate by providing a barrier comprising filtration slits between foot processes, which in aggregate represent a dynamic network of cellular extensions. Foot processes interdigitate with foot processes from adjacent podocytes and form a network of narrow and rather uniform gaps. The fenestrated endothelial cells retain blood cells but permit passage of small solutes and an overlying basement membrane less permeable to macromolecules, in particular to albumin. The cytoskeletal dynamics and structural plasticity of podocytes as well as the signaling between each of these distinct layers are essential for an efficient glomerular filtration and thus for proper renal function. The genetic or acquired impairment of podocytes may lead to foot process effacement (podocyte fusion or retraction), a morphological hallmark of proteinuric renal diseases. Here, we briefly discuss aspects of a contemporary view of podocytes in glomerular filtration, the patterns of structural changes in podocytes associated with common glomerular diseases, and the current state of basic and clinical research.
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Affiliation(s)
- Jochen Reiser
- Department of Medicine, Rush University Medical Center, Chicago, IL, USA
| | - Mehmet M Altintas
- Department of Medicine, Rush University Medical Center, Chicago, IL, USA
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38
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Abstract
Neuromuscular diseases can affect the survival of peripheral neurons, their axons extending to peripheral targets, their synaptic connections onto those targets, or the targets themselves. Examples include motor neuron diseases such as Amyotrophic Lateral Sclerosis, peripheral neuropathies such as Charcot-Marie-Tooth diseases, myasthenias, and muscular dystrophies. Characterizing these phenotypes in mouse models requires an integrated approach, examining both the nerve and muscle histologically, anatomically, and functionally by electrophysiology. Defects observed at these levels can be related back to onset, severity, and progression, as assessed by "Quality of life measures" including tests of gross motor performance such as gait or grip strength. This chapter describes methods for assessing neuromuscular disease models in mice, and how interpretation of these tests can be complicated by the inter-relatedness of the phenotypes.
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Affiliation(s)
- Robert W Burgess
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME, 04609, USA.
| | - Gregory A Cox
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME, 04609, USA
| | - Kevin L Seburn
- The Jackson Laboratory, 600 Main Street, Bar Harbor, ME, 04609, USA
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39
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Clonal culturing of human embryonic stem cells on laminin-521/E-cadherin matrix in defined and xeno-free environment. Nat Commun 2015; 5:3195. [PMID: 24463987 DOI: 10.1038/ncomms4195] [Citation(s) in RCA: 195] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2013] [Accepted: 01/02/2014] [Indexed: 01/22/2023] Open
Abstract
Lack of robust methods for establishment and expansion of pluripotent human embryonic stem (hES) cells still hampers development of cell therapy. Laminins (LN) are a family of highly cell-type specific basement membrane proteins important for cell adhesion, differentiation, migration and phenotype stability. Here we produce and isolate a human recombinant LN-521 isoform and develop a cell culture matrix containing LN-521 and E-cadherin, which both localize to stem cell niches in vivo. This matrix allows clonal derivation, clonal survival and long-term self-renewal of hES cells under completely chemically defined and xeno-free conditions without ROCK inhibitors. Neither LN-521 nor E-cadherin alone enable clonal survival of hES cells. The LN-521/E-cadherin matrix allows hES cell line derivation from blastocyst inner cell mass and single blastomere cells without a need to destroy the embryo. This method can facilitate the generation of hES cell lines for development of different cell types for regenerative medicine purposes.
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Yamada M, Sekiguchi K. Molecular Basis of Laminin-Integrin Interactions. CURRENT TOPICS IN MEMBRANES 2015; 76:197-229. [PMID: 26610915 DOI: 10.1016/bs.ctm.2015.07.002] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Laminins are composed of three polypeptide chains, designated as α, β, and γ. The C-terminal region of laminin heterotrimers, containing coiled-coil regions, short tails, and laminin globular (LG) domains, is necessary and sufficient for binding to integrins, which are the major laminin receptor class. Laminin recognition by integrins critically requires the α chain LG domains and a glutamic acid residue of the γ chain at the third position from the C-terminus. Furthermore, the C-terminal region of the β chain contains a short amino acid sequence that modulates laminin affinity for integrins. Thus, all three of the laminin chains act cooperatively to facilitate integrin binding. Mammals possess 5 α (α1-5), 3 β (β1-3), and 3 γ (γ1-3) chains, combinations of which give rise to 16 distinct laminin isoforms. Each isoform is expressed in a tissue-specific and developmental stage-specific manner, exerting its functions through binding of integrins. In this review, we detail the current knowledge surrounding the molecular basis and physiological relevance of specific interactions between laminins and integrins, and describe the mechanisms underlying laminin action through integrins.
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Affiliation(s)
- Masashi Yamada
- Laboratory of Extracellular Matrix Biochemistry, Institute for Protein Research, Osaka University, Suita, Osaka, Japan
| | - Kiyotoshi Sekiguchi
- Laboratory of Extracellular Matrix Biochemistry, Institute for Protein Research, Osaka University, Suita, Osaka, Japan
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41
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Abstract
The function of the kidney, filtering blood and concentrating metabolic waste into urine, takes place in an intricate and functionally elegant structure called the renal glomerulus. Normal glomerular function retains circulating cells and valuable macromolecular components of plasma in blood, resulting in urine with just trace amounts of proteins. Endothelial cells of glomerular capillaries, the podocytes wrapped around them, and the fused extracellular matrix these cells form altogether comprise the glomerular filtration barrier, a dynamic and highly selective filter that sieves on the basis of molecular size and electrical charge. Current understanding of the structural organization and the cellular and molecular basis of renal filtration draws from studies of human glomerular diseases and animal models of glomerular dysfunction.
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Affiliation(s)
- Rizaldy P Scott
- Feinberg School of Medicine, Northwestern University, Chicago, IL 60611
| | - Susan E Quaggin
- Feinberg School of Medicine, Northwestern University, Chicago, IL 60611
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42
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Chen YM, Liapis H. Focal segmental glomerulosclerosis: molecular genetics and targeted therapies. BMC Nephrol 2015; 16:101. [PMID: 26156092 PMCID: PMC4496884 DOI: 10.1186/s12882-015-0090-9] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 06/16/2015] [Indexed: 12/18/2022] Open
Abstract
Recent advances show that human focal segmental glomerulosclerosis (FSGS) is a primary podocytopathy caused by podocyte-specific gene mutations including NPHS1, NPHS2, WT-1, LAMB2, CD2AP, TRPC6, ACTN4 and INF2. This review focuses on genes discovered in the investigation of complex FSGS pathomechanisms that may have implications for the current FSGS classification scheme. It also recounts recent recommendations for clinical management of FSGS based on translational studies and clinical trials. The advent of next-generation sequencing promises to provide nephrologists with rapid and novel approaches for the diagnosis and treatment of FSGS. A stratified and targeted approach based on the underlying molecular defects is evolving.
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Affiliation(s)
- Ying Maggie Chen
- Renal Division, Washington University School of Medicine, 660 S. Euclid Ave., St. Louis, MO, 63110, USA.
| | - Helen Liapis
- , Nephropath, Little Rock, Arkansas
- Pathology & Immunology, Washington University School of Medicine, St. Louis, MO, USA
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43
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Yurchenco PD. Integrating Activities of Laminins that Drive Basement Membrane Assembly and Function. CURRENT TOPICS IN MEMBRANES 2015; 76:1-30. [PMID: 26610910 DOI: 10.1016/bs.ctm.2015.05.001] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Studies on extracellular matrix proteins, cells, and genetically modified animals have converged to reveal mechanisms of basement membrane self-assembly as mediated by γ1 subunit-containing laminins, the focus of this chapter. The basic model is as follows: A member of the laminin family adheres to a competent cell surface and typically polymerizes followed by laminin binding to the extracellular adaptor proteins nidogen, perlecan, and agrin. Assembly is completed by the linking of nidogen and heparan sulfates to type IV collagen, allowing it to form a second stabilizing network polymer. The assembled matrix provides structural support, anchoring the extracellular matrix to the cytoskeleton, and acts as a signaling platform. Heterogeneity of function is created in part by the isoforms of laminin that vary in their ability to polymerize and to interact with integrins, dystroglycan, and other receptors. Mutations in laminin subunits, affecting expression or LN domain-specific functions, are a cause of human diseases that include those of muscle, nerve, brain, and kidney.
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Affiliation(s)
- Peter D Yurchenco
- Department of Pathology & Laboratory Medicine, Robert Wood Johnson Medical School, Rutgers University, Piscataway, NJ, USA.
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Chung JJ, Huber TB, Gödel M, Jarad G, Hartleben B, Kwoh C, Keil A, Karpitskiy A, Hu J, Huh CJ, Cella M, Gross RW, Miner JH, Shaw AS. Albumin-associated free fatty acids induce macropinocytosis in podocytes. J Clin Invest 2015; 125:2307-16. [PMID: 25915582 DOI: 10.1172/jci79641] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 03/19/2015] [Indexed: 01/26/2023] Open
Abstract
Podocytes are specialized epithelial cells in the kidney glomerulus that play important structural and functional roles in maintaining the filtration barrier. Nephrotic syndrome results from a breakdown of the kidney filtration barrier and is associated with proteinuria, hyperlipidemia, and edema. Additionally, podocytes undergo changes in morphology and internalize plasma proteins in response to this disorder. Here, we used fluid-phase tracers in murine models and determined that podocytes actively internalize fluid from the plasma and that the rate of internalization is increased when the filtration barrier is disrupted. In cultured podocytes, the presence of free fatty acids (FFAs) associated with serum albumin stimulated macropinocytosis through a pathway that involves FFA receptors, the Gβ/Gγ complex, and RAC1. Moreover, mice with elevated levels of plasma FFAs as the result of a high-fat diet were more susceptible to Adriamycin-induced proteinuria than were animals on standard chow. Together, these results support a model in which podocytes sense the disruption of the filtration barrier via FFAs bound to albumin and respond by enhancing fluid-phase uptake. The response to FFAs may function in the development of nephrotic syndrome by amplifying the effects of proteinuria.
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Borza CM, Chen X, Zent R, Pozzi A. Cell Receptor-Basement Membrane Interactions in Health and Disease: A Kidney-Centric View. CURRENT TOPICS IN MEMBRANES 2015; 76:231-53. [PMID: 26610916 PMCID: PMC4913201 DOI: 10.1016/bs.ctm.2015.07.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Cell-extracellular matrix (ECM) interactions are essential for tissue development, homeostasis, and response to injury. Basement membranes (BMs) are specialized ECMs that separate epithelial or endothelial cells from stromal components and interact with cells via cellular receptors, including integrins and discoidin domain receptors. Disruption of cell-BM interactions due to either injury or genetic defects in either the ECM components or cellular receptors often lead to irreversible tissue injury and loss of organ function. Animal models that lack specific BM components or receptors either globally or in selective tissues have been used to help with our understanding of the molecular mechanisms whereby cell-BM interactions regulate organ function in physiological and pathological conditions. We review recently published works on animal models that explore how cell-BM interactions regulate kidney homeostasis in both health and disease.
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Affiliation(s)
- Corina M. Borza
- Department of Medicine, Division of Nephrology, Vanderbilt University Medical Center, Nashville, TN, 37232
- Vanderbilt Center for Kidney Disease, Vanderbilt University Medical Center, Nashville, TN, 37232
| | - Xiwu Chen
- Department of Medicine, Division of Nephrology, Vanderbilt University Medical Center, Nashville, TN, 37232
| | - Roy Zent
- Department of Medicine, Division of Nephrology, Vanderbilt University Medical Center, Nashville, TN, 37232
- Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, TN, 37232
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN, 37232
- Vanderbilt Center for Kidney Disease, Vanderbilt University Medical Center, Nashville, TN, 37232
- Department of Medicine, Veterans Administration Hospital, Nashville, TN, 37232
| | - Ambra Pozzi
- Department of Medicine, Division of Nephrology, Vanderbilt University Medical Center, Nashville, TN, 37232
- Department of Cancer Biology, Vanderbilt University Medical Center, Nashville, TN, 37232
- Department of Molecular Physiology and Biophysics, Vanderbilt University Medical Center, Nashville, TN, 37232
- Vanderbilt Center for Kidney Disease, Vanderbilt University Medical Center, Nashville, TN, 37232
- Department of Medicine, Veterans Administration Hospital, Nashville, TN, 37232
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Katagiri F, Takagi M, Nakamura M, Tanaka Y, Hozumi K, Kikkawa Y, Nomizu M. Screening of integrin-binding peptides in a laminin peptide library derived from the mouse laminin β chain short arm regions. Arch Biochem Biophys 2014; 550-551:33-41. [PMID: 24785228 DOI: 10.1016/j.abb.2014.04.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Revised: 04/01/2014] [Accepted: 04/19/2014] [Indexed: 10/25/2022]
Abstract
Laminins, major components of basement membrane, consist of three different subunits, α, β, and γ chains, and so far, five α, three β, and three γ chains have been identified. We have constructed synthetic peptide libraries derived from the laminin sequences and identified various cell-adhesive peptides. Ten active peptides from the laminin α chain sequences (α1-α5) were found to promote integrin-mediated cell adhesion. Previously, we found fourteen cell-adhesive peptides from the β1 chain sequence but their receptors have not been analyzed. Here, we expanded the synthetic peptide library to add peptides from the short arm regions of the laminin β2 and β3 chains and screened for integrin-binding peptides. Twenty-seven peptides promoted human dermal fibroblast (HDF) attachment in a peptide-coated plate assay. The morphological appearance of HDFs on the peptide-coated plates differed depending on the peptides. B34 (REKYYYAVYDMV, mouse laminin β1 chain, 255-266), B67 (IPYSMEYEILIRY, mouse laminin β1 chain, 604-616), B2-105 (APNFWNFTSGRG, mouse laminin β2 chain, 1081-1092), and B3-19 (GHLTGGKVQLNL, mouse laminin β3 chain, 182-193) promoted HDF spreading and HDF attachment was inhibited by EDTA, suggesting that the peptides interact with integrins. Immunostaining analyses revealed that B67 induced well-organized actin stress fibers and focal contacts containing vinculin, however, B34, B2-105, and B3-19 did not exhibit stress fiber formation or focal contacts. The inhibition assay using anti-integrin antibodies indicated that B67 interacts with α3, α6, and β1 integrins, and B34 and B3-19 interact with β1 integrin. Based on adhesion analysis of peptides modified with an alanine scan and on switching analysis with the homologous inactive sequence B2-64 (LPRAMDYDLLLRW, mouse laminin β2 chain, 618-630), the Glu(8) residue in the B67 peptide was critical for HDF adhesion. These findings are useful for identifying an integrin binding motif. The B67 peptide has potential for use as a molecular probe for integrins.
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Affiliation(s)
- Fumihiko Katagiri
- Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Masaharu Takagi
- Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Minako Nakamura
- Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Yoichiro Tanaka
- Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Kentaro Hozumi
- Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Yamato Kikkawa
- Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan
| | - Motoyoshi Nomizu
- Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392, Japan.
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Bull KR, Mason T, Rimmer AJ, Crockford TL, Silver KL, Bouriez-Jones T, Hough TA, Chaudhry S, Roberts ISD, Goodnow CC, Cornall RJ. Next-generation sequencing to dissect hereditary nephrotic syndrome in mice identifies a hypomorphic mutation in Lamb2 and models Pierson's syndrome. J Pathol 2014; 233:18-26. [PMID: 24293254 PMCID: PMC4241031 DOI: 10.1002/path.4308] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Revised: 11/15/2013] [Accepted: 11/21/2013] [Indexed: 01/11/2023]
Abstract
The study of mutations causing the steroid-resistant nephrotic syndrome in children has greatly advanced our understanding of the kidney filtration barrier. In particular, these genetic variants have illuminated the roles of the podocyte, glomerular basement membrane and endothelial cell in glomerular filtration. However, in a significant number of familial and early onset cases, an underlying mutation cannot be identified, indicating that there are likely to be multiple unknown genes with roles in glomerular permeability. We now show how the combination of N-ethyl-N-nitrosourea mutagenesis and next-generation sequencing could be used to identify the range of mutations affecting these pathways. Using this approach, we isolated a novel mouse strain with a viable nephrotic phenotype and used whole-genome sequencing to isolate a causative hypomorphic mutation in Lamb2. This discovery generated a model for one part of the spectrum of human Pierson's syndrome and provides a powerful proof of principle for accelerating gene discovery and improving our understanding of inherited forms of renal disease.
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Affiliation(s)
- Katherine R Bull
- Nuffield Department of Medicine and Wellcome Trust Centre for Human Genetics, Oxford UniversityUK
| | - Thomas Mason
- Nuffield Department of Medicine and Wellcome Trust Centre for Human Genetics, Oxford UniversityUK
| | - Andrew J Rimmer
- Nuffield Department of Medicine and Wellcome Trust Centre for Human Genetics, Oxford UniversityUK
| | - Tanya L Crockford
- Nuffield Department of Medicine and Wellcome Trust Centre for Human Genetics, Oxford UniversityUK
- MRC Human Immunology Unit, Weatherall Institute for Molecular Medicine, Oxford UniversityUK
| | - Karlee L Silver
- Nuffield Department of Medicine and Wellcome Trust Centre for Human Genetics, Oxford UniversityUK
| | - Tiphaine Bouriez-Jones
- Nuffield Department of Medicine and Wellcome Trust Centre for Human Genetics, Oxford UniversityUK
| | - Tertius A Hough
- MRC Harwell, Harwell Science and Innovation CampusOxfordshire, UK
| | - Shirine Chaudhry
- Australian Phenomics Facility, Australian National UniversityCanberra, Australia
| | - Ian SD Roberts
- Oxford University Hospitals NHS Trust, John Radcliffe Hospital, Headington, OxfordUK
| | - Christopher C Goodnow
- Department of Immunology, John Curtin School of Medical Research, Australian National UniversityCanberra, Australia
| | - Richard J Cornall
- Nuffield Department of Medicine and Wellcome Trust Centre for Human Genetics, Oxford UniversityUK
- MRC Human Immunology Unit, Weatherall Institute for Molecular Medicine, Oxford UniversityUK
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A mouse Col4a4 mutation causing Alport glomerulosclerosis with abnormal collagen α3α4α5(IV) trimers. Kidney Int 2014; 85:1461-8. [PMID: 24522496 PMCID: PMC4040157 DOI: 10.1038/ki.2013.493] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Revised: 09/11/2013] [Accepted: 10/03/2013] [Indexed: 12/31/2022]
Abstract
A spontaneous mutation termed bilateral wasting kidneys (bwk) was identified in a colony of NONcNZO recombinant inbred mice. These mice exhibit a rapid increase of urinary albumin at an early age associated with glomerulosclerosis, interstitial nephritis, and tubular atrophy. The mutation was mapped to a location on chromosome 1 containing the Col4a3 and Col4a4 genes, for which mutations in the human orthologs cause the hereditary nephritis Alport syndrome. DNA sequencing identified a G-to-A mutation in the conserved GT splice donor of Col4a4 intron 30, resulting in skipping of exon 30 but maintaining the mRNA reading frame. Protein analyses showed that mutant collagen α3α4α5(IV) trimers were secreted and incorporated into the glomerular basement membrane (GBM), but levels were low, and GBM lesions typical of Alport syndrome were observed. Moving the mutation into the more renal damage-prone DBA/2J and 129S1/SvImJ backgrounds revealed differences in albuminuria and its rate of increase, suggesting an interaction between the Col4a4 mutation and modifier genes. This novel mouse model of Alport syndrome is the only one shown to accumulate abnormal collagen α3α4α5(IV) in the GBM, as also found in a subset of Alport patients. These mice will be valuable for testing potential therapies, for understanding abnormal collagen IV structure and assembly, and for gaining better insights into the mechanisms leading to Alport syndrome, and to the variability in the age of onset and associated phenotypes.
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Byron A, Randles MJ, Humphries JD, Mironov A, Hamidi H, Harris S, Mathieson PW, Saleem MA, Satchell SC, Zent R, Humphries MJ, Lennon R. Glomerular cell cross-talk influences composition and assembly of extracellular matrix. J Am Soc Nephrol 2014; 25:953-66. [PMID: 24436469 DOI: 10.1681/asn.2013070795] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The glomerular basement membrane (GBM) is a specialized extracellular matrix (ECM) compartment within the glomerulus that contains tissue-restricted isoforms of collagen IV and laminin. It is integral to the capillary wall and therefore, functionally linked to glomerular filtration. Although the composition of the GBM has been investigated with global and candidate-based approaches, the relative contributions of glomerular cell types to the production of ECM are not well understood. To characterize specific cellular contributions to the GBM, we used mass spectrometry-based proteomics to analyze ECM isolated from podocytes and glomerular endothelial cells in vitro. These analyses identified cell type-specific differences in ECM composition, indicating distinct contributions to glomerular ECM assembly. Coculture of podocytes and endothelial cells resulted in an altered composition and organization of ECM compared with monoculture ECMs, and electron microscopy revealed basement membrane-like ECM deposition between cocultured cells, suggesting the involvement of cell-cell cross-talk in the production of glomerular ECM. Notably, compared with monoculture ECM proteomes, the coculture ECM proteome better resembled a tissue-derived glomerular ECM dataset, indicating its relevance to GBM in vivo. Protein network analyses revealed a common core of 35 highly connected structural ECM proteins that may be important for glomerular ECM assembly. Overall, these findings show the complexity of the glomerular ECM and suggest that both ECM composition and organization are context-dependent.
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Affiliation(s)
- Adam Byron
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences and
| | - Michael J Randles
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences and Faculty of Medical and Human Sciences, University of Manchester, Manchester, United Kingdom
| | | | - Aleksandr Mironov
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences and
| | - Hellyeh Hamidi
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences and
| | - Shelley Harris
- Faculty of Medical and Human Sciences, University of Manchester, Manchester, United Kingdom
| | - Peter W Mathieson
- Academic Renal Unit, Faculty of Medicine and Dentistry, University of Bristol, Bristol, United Kingdom
| | - Moin A Saleem
- Academic Renal Unit, Faculty of Medicine and Dentistry, University of Bristol, Bristol, United Kingdom
| | - Simon C Satchell
- Academic Renal Unit, Faculty of Medicine and Dentistry, University of Bristol, Bristol, United Kingdom
| | - Roy Zent
- Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee; and Department of Medicine, Veterans Affairs Hospital, Nashville, Tennessee
| | - Martin J Humphries
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences and
| | - Rachel Lennon
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences and Faculty of Medical and Human Sciences, University of Manchester, Manchester, United Kingdom;
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Lennon R, Randles MJ, Humphries MJ. The importance of podocyte adhesion for a healthy glomerulus. Front Endocrinol (Lausanne) 2014; 5:160. [PMID: 25352829 PMCID: PMC4196579 DOI: 10.3389/fendo.2014.00160] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Accepted: 09/21/2014] [Indexed: 12/23/2022] Open
Abstract
Podocytes are specialized epithelial cells that cover the outer surfaces of glomerular capillaries. Unique cell junctions, known as slit diaphragms, which feature nephrin and Neph family proteins in addition to components of adherens, tight, and gap junctions, connect adjacent podocyte foot processes. Single gene disorders affecting the slit diaphragm result in nephrotic syndrome in humans, characterized by massive loss of protein across the capillary wall. In addition to specialized cell junctions, interconnecting podocytes also adhere to the glomerular basement membrane (GBM) of the capillary wall. The GBM is a dense network of secreted, extracellular matrix (ECM) components and contains tissue-restricted isoforms of collagen IV and laminin in addition to other structural proteins and ECM regulators such as proteases and growth factors. The specialized niche of the GBM provides a scaffold for endothelial cells and podocytes to support their unique functions and human genetic mutations in GBM components lead to renal failure, thus highlighting the importance of cell-matrix interactions in the glomerulus. Cells adhere to ECM via adhesion receptors, including integrins, syndecans, and dystroglycan and in particular the integrin heterodimer α3β1 is required to maintain barrier integrity. Therefore, the sophisticated function of glomerular filtration relies on podocyte adhesion both at cell junctions and at the interface with the ECM. In health, the podocyte coordinates signals from cell junctions and cell-matrix interactions, in response to environmental cues in order to regulate filtration and as our understanding of mechanisms that control cell adhesion in the glomerulus develops, then insight into the effects of disease will improve. The ultimate goal will be to develop targeted therapies to prevent or repair defects in the filtration barrier and to restore glomerular function.
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Affiliation(s)
- Rachel Lennon
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, The University of Manchester, Manchester, UK
- Institute of Human Development, Faculty of Medical and Human Sciences, The University of Manchester, Manchester, UK
- Department of Paediatric Nephrology, Manchester Academic Health Science Centre, Central Manchester University Hospitals NHS Foundation Trust, Manchester, UK
- *Correspondence: Rachel Lennon, Wellcome Trust Centre for Cell-Matrix Research, The University of Manchester, Michael Smith Building, Manchester M13 9PT, UK e-mail:
| | - Michael J. Randles
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, The University of Manchester, Manchester, UK
- Institute of Human Development, Faculty of Medical and Human Sciences, The University of Manchester, Manchester, UK
| | - Martin J. Humphries
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, The University of Manchester, Manchester, UK
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