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Sethi S, Shakyawar S, Reddy AS, Patel JC, Guda C. A Machine Learning Model for the Prediction of COVID-19 Severity Using RNA-Seq, Clinical, and Co-Morbidity Data. Diagnostics (Basel) 2024; 14:1284. [PMID: 38928699 PMCID: PMC11202902 DOI: 10.3390/diagnostics14121284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 05/29/2024] [Accepted: 06/12/2024] [Indexed: 06/28/2024] Open
Abstract
The premise for this study emanated from the need to understand SARS-CoV-2 infections at the molecular level and to develop predictive tools for managing COVID-19 severity. With the varied clinical outcomes observed among infected individuals, creating a reliable machine learning (ML) model for predicting the severity of COVID-19 became paramount. Despite the availability of large-scale genomic and clinical data, previous studies have not effectively utilized multi-modality data for disease severity prediction using data-driven approaches. Our primary goal is to predict COVID-19 severity using a machine-learning model trained on a combination of patients' gene expression, clinical features, and co-morbidity data. Employing various ML algorithms, including Logistic Regression (LR), XGBoost (XG), Naïve Bayes (NB), and Support Vector Machine (SVM), alongside feature selection methods, we sought to identify the best-performing model for disease severity prediction. The results highlighted XG as the superior classifier, with 95% accuracy and a 0.99 AUC (Area Under the Curve), for distinguishing severity groups. Additionally, the SHAP analysis revealed vital features contributing to prediction, including several genes such as COX14, LAMB2, DOLK, SDCBP2, RHBDL1, and IER3-AS1. Notably, two clinical features, the absolute neutrophil count and Viremia Categories, emerged as top contributors. Integrating multiple data modalities has significantly improved the accuracy of disease severity prediction compared to using any single modality. The identified features could serve as biomarkers for COVID-19 prognosis and patient care, allowing clinicians to optimize treatment strategies and refine clinical decision-making processes for enhanced patient outcomes.
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Affiliation(s)
- Sahil Sethi
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE 68105, USA
| | - Sushil Shakyawar
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE 68105, USA
| | - Athreya S. Reddy
- Bond Life Sciences Center, University of Missouri, Columbia, MO 65211, USA
| | - Jai Chand Patel
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE 68105, USA
| | - Chittibabu Guda
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE 68105, USA
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Paiz F, Alawneh I, Nigro E, Gonorazky HD. Expanding the spectrum of LAMB2: Pierson syndrome associated with neuromuscular junction disorder in two patients. Neuromuscul Disord 2024; 39:30-32. [PMID: 38723581 DOI: 10.1016/j.nmd.2024.03.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 03/04/2024] [Accepted: 03/18/2024] [Indexed: 06/15/2024]
Abstract
LAMB2 gene disorders present with different phenotypes. Pierson syndrome (PS) is a common phenotype associated with LAMB2 variants. Neuromuscular phenotype has been reported including hypotonia and developmental delay. However, neuromuscular junction abnormalities represented as congenital myasthenic syndrome (CMS) was reported in one adult patient only. Here, in this paper, we present two pediatric cases with a severe presentation of PS and have CMS so expanding the knowledge of LAMB2 related phenotypes. The first patient had hypotonia and global developmental delay. Targeted genetic testing panel demonstrated homozygous pathogenic variant in the LAMB2 gene (c.5182C>T, pGln1728*) which was reported by Maselli et al. 2009. Repetitive nerve stimulation (RNS) showed a decremental response at low frequency of 3 Hz. On the other hand, the second patient had profound weakness since birth. Tri-Whole exome sequencing showed homozygous pathogenic variant in the LAMB2 gene c.2890C>T, pArg964*. A trial of salbutamol did not improve the symptoms. Both patients passed away from sequala of PS. The spectrum of phenotypic changes associated with LAMB2 mutations is still expanding, and further investigation into the various clinical and morphologic presentations associated with these mutations is important to better identify and manage affected individuals.
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Affiliation(s)
- Freddy Paiz
- Division of Neurology, The Hospital for Sick Children, University of Toronto, Toronto, Canada
| | - Issa Alawneh
- Division of Neurology, The Hospital for Sick Children, University of Toronto, Toronto, Canada
| | - Elisa Nigro
- Division of Neurology, The Hospital for Sick Children, University of Toronto, Toronto, Canada
| | - Hernan D Gonorazky
- Division of Neurology, The Hospital for Sick Children, University of Toronto, Toronto, Canada; Program of Genetic and Genome Biology, The Hospital for Sick Children, University of Toronto, Toronto, Canada.
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3
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Mitrotti A, Giliberti M, Di Leo V, di Bari I, Pontrelli P, Gesualdo L. Hidden genetics behind glomerular scars: an opportunity to understand the heterogeneity of focal segmental glomerulosclerosis? Pediatr Nephrol 2024; 39:1685-1707. [PMID: 37728640 PMCID: PMC11026212 DOI: 10.1007/s00467-023-06046-1] [Citation(s) in RCA: 1] [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: 01/03/2023] [Revised: 05/02/2023] [Accepted: 05/30/2023] [Indexed: 09/21/2023]
Abstract
Focal segmental glomerulosclerosis (FSGS) is a complex disease which describes different kinds of kidney defects, not exclusively linked with podocyte defects. Since nephrin mutation was first described in association with early-onset nephrotic syndrome (NS), many advancements have been made in understanding genetic patterns associated with FSGS. New genetic causes of FSGS have been discovered, displaying unexpected genotypes, and recognizing possible site of damage. Many recent large-scale sequencing analyses on patients affected by idiopathic chronic kidney disease (CKD), kidney failure (KF) of unknown origin, or classified as FSGS, have revealed collagen alpha IV genes, as one of the most frequent sites of pathogenic mutations. Also, recent interest in complex and systemic lysosomal storage diseases, such as Fabry disease, has highlighted GLA mutations as possible causes of FSGS. Tubulointerstitial disease, recently classified by KDIGO based on genetic subtypes, when associated with UMOD variants, may phenotypically gain FSGS features, as well as ciliopathy genes or others, otherwise leading to completely different phenotypes, but found carrying pathogenic variants with associated FSGS phenotype. Thus, glomerulosclerosis may conceal different heterogeneous conditions. When a kidney biopsy is performed, the principal objective is to provide an accurate diagnosis. The broad spectrum of phenotypic expression and genetic complexity is demonstrating that a combined path of management needs to be applied. Genetic investigation should not be reserved only to selected cases, but rather part of medical management, integrating with clinical and renal pathology records. FSGS heterogeneity should be interpreted as an interesting opportunity to discover new pathways of CKD, requiring prompt genotype-phenotype correlation. In this review, we aim to highlight how FSGS represents a peculiar kidney condition, demanding multidisciplinary management, and in which genetic analysis may solve some otherwise unrevealed idiopathic cases. Unfortunately there is not a uniform correlation between specific mutations and FSGS morphological classes, as the same variants may be identified in familial cases or sporadic FSGS/NS or manifest a variable spectrum of the same disease. These non-specific features make diagnosis challenging. The complexity of FSGS genotypes requires new directions. Old morphological classification does not provide much information about the responsible cause of disease and misdiagnoses may expose patients to immunosuppressive therapy side effects, mistaken genetic counseling, and misguided kidney transplant programs.
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Affiliation(s)
- Adele Mitrotti
- Precision and Regenerative Medicine and Ionian Area, Nephrology, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy.
| | - Marica Giliberti
- Precision and Regenerative Medicine and Ionian Area, Nephrology, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Vincenzo Di Leo
- Precision and Regenerative Medicine and Ionian Area, Nephrology, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Ighli di Bari
- Precision and Regenerative Medicine and Ionian Area, Nephrology, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Paola Pontrelli
- Precision and Regenerative Medicine and Ionian Area, Nephrology, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
| | - Loreto Gesualdo
- Precision and Regenerative Medicine and Ionian Area, Nephrology, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari Aldo Moro, Bari, Italy
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Tseng MH, Lin SH, Fan WL, Wu TW, Lin SP, Ding JJ, Tsai IJ, Tsai JD. Phenotype, genotype, and clinical outcome of Taiwanese with congenital nephrotic syndrome. J Formos Med Assoc 2024; 123:647-654. [PMID: 37845138 DOI: 10.1016/j.jfma.2023.10.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 07/15/2023] [Accepted: 10/02/2023] [Indexed: 10/18/2023] Open
Abstract
BACKGROUND/PURPOSE Congenital nephrotic syndrome (CNS) is one of the important causes of end-stage kidney disease in children. Studies on the genotype, phenotype, and clinical outcome in infants with CNS caused by genetic mutations are scarce. METHODS We analyzed the genetic background, clinical manifestations, treatment response, and prognosis of pediatric patients with CNS in Taiwan. RESULTS Fifteen infants with CNS were enrolled, and 11 patients of median age 21 (interquartile range 3∼44) days caused by genetic mutations from 10 unrelated families were included in the study. Of the eleven patients, 9 had extra-renal manifestations including microcephaly, facial dysmorphism, and skeletal anomalies. More than two-thirds of the patients had disease onset before 1 month of age. Diffuse meningeal sclerosis was the most common histological characteristic. Whole exome sequencing followed by direct Sanger sequence revealed mutations in OSGEP (R247Q), WT1 (R366H and R467Q), LAMB2 (Q1209∗ and c. 5432-5451 19 bp deletion), NUP93 (D302V), and LAGE3 (c.188+1G > A). Three of the variants were novel. Corticosteroids and/or immunosuppressants were administered in 2 patients, but both were refractory to treatment. During the mean 3.5 years of follow-up, all but two died of uremia and sepsis. The two survivors reached end-stage kidney disease and required peritoneal dialysis, and one of them underwent uneventful renal transplantation. CONCLUSION The majority of patients with CNS in Taiwan were caused by OSGEP followed by WT1 mutation. R247Q is the hotspot mutation of OSGEP in Taiwan. CNS patients in Taiwan suffer from significant morbidity and mortality.
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Affiliation(s)
- Min-Hua Tseng
- Division of Nephrology, Department of Pediatrics, Chang Gung Memorial Hospital and Chang Gung University, Taoyuan, Taiwan
| | - Shih-Hua Lin
- Division of Nephrology, Department of Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - Wen-Lang Fan
- Genomic Medicine Core Laboratory, Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Ta-Wei Wu
- Fetal and Neonatal Institute, Division of Neonatology, Children's Hospital Los Angeles, CA, USA; Department of Pediatrics, University of Southern California Keck School of Medicine, Los Angeles, CA, USA
| | - Shuan-Pei Lin
- Division of Pediatric Genetics, Department of Pediatrics, MacKay Children's Hospital, Taipei, Taiwan
| | - Jhao-Jhuang Ding
- Department of Pediatrics, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
| | - I-Jung Tsai
- Division of Nephrology, Department of Pediatrics, National Taiwan University Children's Hospital, Taipei, Taiwan.
| | - Jeng-Daw Tsai
- Division of Nephrology, Department of Pediatrics, MacKay Children's Hospital, Taipei, Taiwan; Department of Medicine, MacKay Medical College, New Taipei City, Taiwan; Department of Pediatrics, Taipei Medical University Hospital, Taipei, Taiwan; Department of Pediatrics, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
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5
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Finn LS. Nephrotic Syndrome Throughout Childhood: Diagnosing Podocytopathies From the Womb to the Dorm. Pediatr Dev Pathol 2024:10935266241242669. [PMID: 38745407 DOI: 10.1177/10935266241242669] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/16/2024]
Abstract
The etiologies of podocyte dysfunction that lead to pediatric nephrotic syndrome (NS) are vast and vary with age at presentation. The discovery of numerous novel genetic podocytopathies and the evolution of diagnostic technologies has transformed the investigation of steroid-resistant NS while simultaneously promoting the replacement of traditional morphology-based disease classifications with a mechanistic approach. Podocytopathies associated with primary and secondary steroid-resistant NS manifest as diffuse mesangial sclerosis, minimal change disease, focal segmental glomerulosclerosis, and collapsing glomerulopathy. Molecular testing, once an ancillary option, has become a vital component of the clinical investigation and when paired with kidney biopsy findings, provides data that can optimize treatment and prognosis. This review focuses on the causes including selected monogenic defects, clinical phenotypes, histopathologic findings, and age-appropriate differential diagnoses of nephrotic syndrome in the pediatric population with an emphasis on podocytopathies.
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Affiliation(s)
- Laura S Finn
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine at The University of Pennsylvania, The Children's Hospital of Philadelphia, Philadelphia, PA, USA
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Dhanorkar MA, Rao S N, Malhotra KP, Ansari M, Chandra A. Novel NUP93 Gene Variant and Diffuse Mesangial Sclerosis in Steroid Resistant Nephrotic Syndrome. Indian J Pediatr 2024; 91:517. [PMID: 37855858 DOI: 10.1007/s12098-023-04887-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 09/27/2023] [Indexed: 10/20/2023]
Affiliation(s)
- Manoj Anant Dhanorkar
- Department of Nephrology, Dr. Ram Manohar, Lohia Institute of Medical Sciences (RMLIMS), Lucknow, Uttar Pradesh, India.
| | - Namrata Rao S
- Department of Nephrology, Dr. Ram Manohar, Lohia Institute of Medical Sciences (RMLIMS), Lucknow, Uttar Pradesh, India
| | - Kiran Preet Malhotra
- Department of Pathology, Dr. Ram Manohar Lohia Institute of Medical Sciences (RMLIMS), Lucknow, Uttar Pradesh, India
| | - Majibullah Ansari
- Department of Nephrology, Dr. Ram Manohar, Lohia Institute of Medical Sciences (RMLIMS), Lucknow, Uttar Pradesh, India
| | - Abhilash Chandra
- Department of Nephrology, Dr. Ram Manohar, Lohia Institute of Medical Sciences (RMLIMS), Lucknow, Uttar Pradesh, India
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7
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Martínez-López J, Márquez A, Pegoraro F, Ortiz-Fernández L, Acosta-Herrera M, Kerick M, Gelain E, Diamond EL, Durham BH, Abdel-Wahab O, Go RS, Koster MJ, Dagna L, Campochiaro C, Collin M, Milne P, Estrada-Veras JI, O’Brien K, Papo M, Cohen-Aubar F, Amoura Z, Haroche J, Martín J, Vaglio A. Genome-Wide Association Study Identifies the First Germline Genetic Variant Associated With Erdheim-Chester Disease. Arthritis Rheumatol 2024; 76:141-145. [PMID: 37561109 PMCID: PMC10841187 DOI: 10.1002/art.42673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 07/12/2023] [Accepted: 08/07/2023] [Indexed: 08/11/2023]
Abstract
OBJECTIVE Erdheim-Chester disease (ECD) is rare histiocytosis with a wide range of clinical manifestations. Somatic mutations are key to the pathogenesis of the disease; however, the relationship between germline genetic variants and ECD has not been examined so far. The present study aims to explore the inherited genetic component of ECD by performing the first genome-wide association study. METHODS After quality controls, a cohort of 255 patients with ECD and 7,471 healthy donors was included in this study. Afterward, a logistic regression followed by in silico functional annotation was performed. RESULTS A signal at the 18q12.3 genomic region was identified as a new susceptibility locus for ECD (P = 2.75 × 10-11 ; Odds Ratio = 2.09). This association was annotated to the SETBP1 gene, which is involved in clonal haematopoiesis. Functional annotation of this region and of the identified suggestive signals revealed additional genes that could be potentially involved in the pathogenesis of the disease. CONCLUSION Overall, this work demonstrates that germline genetic variants can impact on the development of ECD and suggests new pathways with a potential pathogenic role.
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Affiliation(s)
- Javier Martínez-López
- Institute of Parasitology and Biomedicine López-Neyra. Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), Granada, Spain
| | - Ana Márquez
- Institute of Parasitology and Biomedicine López-Neyra. Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), Granada, Spain
| | - Francesco Pegoraro
- Department of Health Sciences, University of Florence, Florence, Italy
- Pediatric Hematology and Oncology Unit, Meyer Children’s Hospital IRCCS, Florence, Italy
| | - Lourdes Ortiz-Fernández
- Institute of Parasitology and Biomedicine López-Neyra. Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), Granada, Spain
| | - Marialbert Acosta-Herrera
- Institute of Parasitology and Biomedicine López-Neyra. Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), Granada, Spain
- Systemic Autoimmune Disease Unit, Hospital Clínico San Cecilio, Instituto de Investigación Biosanitaria Ibs. Granada, Spain
| | - Martin Kerick
- Institute of Parasitology and Biomedicine López-Neyra. Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), Granada, Spain
| | - Elena Gelain
- Nephrology and Dialysis Unit, Meyer Children’s Hospital IRCCS, Florence, Italy
| | - Eli L. Diamond
- Department of Neurology, Memorial Sloan Kettering Cancer Center, New York, USA
| | - Benjamin H. Durham
- Department of Pathology and Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, NY United States
- Molecular Pharmacology Program, Memorial Sloan Kettering Cancer Center, New York, NY United States
| | - Omar Abdel-Wahab
- Human Oncology and Pathogenesis Program, Dept. of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | | | | | - Lorenzo Dagna
- Immunology, Rheumatology, Allergy and Rare Disease Unit, IRCCS San Raffaele Scientific Institute; Vita-Salute San Raffaele University, Milano, Italy
| | - Corrado Campochiaro
- Immunology, Rheumatology, Allergy and Rare Disease Unit, IRCCS San Raffaele Scientific Institute; Vita-Salute San Raffaele University, Milano, Italy
| | - Matthew Collin
- Clinical and Translational Research Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Paul Milne
- Clinical and Translational Research Institute, Newcastle University, Newcastle upon Tyne, UK
| | - Juvianee I. Estrada-Veras
- Office of the Clinical Director, National Human Genome Research Institute, NIH, Bethesda, Maryland, USA
| | - Kevin O’Brien
- Office of the Clinical Director, National Human Genome Research Institute, NIH, Bethesda, Maryland, USA
| | - Matthias Papo
- Sorbonne Université, Assistance Publique-Hôpitaux de Paris, Service de Médecine Interne
- Centre National de Référence Maladies Systémiques Rares et Histiocytoses, Hôpital Pitié-Salpêtrière, Centre d’immunologie et des maladies infectieuses INSERM UMRS1135, F-75013 Paris, France
| | - Fleur Cohen-Aubar
- Sorbonne Université, Assistance Publique-Hôpitaux de Paris, Service de Médecine Interne
| | - Zahir Amoura
- Sorbonne Université, Assistance Publique-Hôpitaux de Paris, Service de Médecine Interne
- Centre National de Référence Maladies Systémiques Rares et Histiocytoses, Hôpital Pitié-Salpêtrière, Centre d’immunologie et des maladies infectieuses INSERM UMRS1135, F-75013 Paris, France
| | - Julien Haroche
- Sorbonne Université, Assistance Publique-Hôpitaux de Paris, Service de Médecine Interne
- Centre National de Référence Maladies Systémiques Rares et Histiocytoses, Hôpital Pitié-Salpêtrière, Centre d’immunologie et des maladies infectieuses INSERM UMRS1135, F-75013 Paris, France
| | - Javier Martín
- Institute of Parasitology and Biomedicine López-Neyra. Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), Granada, Spain
| | - Augusto Vaglio
- Nephrology and Dialysis Unit, Meyer Children’s Hospital IRCCS, Florence, Italy
- Department of Biomedical, Experimental and Clinical Sciences, University of Florence, Florence Italy
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Leventoğlu E, Dönmez E, Uzun Kenan B, Yazıcıoğlu B, Büyükkaragöz B, Fidan K, Bakkaloğlu SA, Söylemezoğlu O. LAMB2 gene: broad clinical spectrum in Pierson syndrome. CEN Case Rep 2023:10.1007/s13730-023-00838-y. [PMID: 38038886 DOI: 10.1007/s13730-023-00838-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: 08/12/2023] [Accepted: 11/06/2023] [Indexed: 12/02/2023] Open
Abstract
Pierson syndrome (PS) is a rare autosomal recessive disease, characterized by congenital nephrotic syndrome (CNS), and ocular and neurologic abnormalities. In affected cases, there is abnormal b-2 laminin which is compound of the several basement membranes caused by inherited mutations in the LAMB2 gene. Although patients have mutations in the same gene, the phenotype is highly variable. In this case series, the relationship between genotype and phenotype is emphasized, and information about the clinical follow-up of the patients is presented. Hereby, we report four pediatric cases with PS as a result of mutation in the LAMB2 gene. Clinical spectrum of LAMB2-associated disorders varies from mild-to-severe ocular, kidney, and neurologic involvement. Since genotype-phenotype correlation in PS has not been clearly demonstrated, we recommend that all patients with ophthalmic anomalies and glomerular proteinuria should be tested for LAMB2 mutations.
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Affiliation(s)
- Emre Leventoğlu
- Department of Pediatric Nephrology, Faculty of Medicine, Gazi University, Ankara, Turkey.
| | - Emine Dönmez
- Department of Pediatrics, Faculty of Medicine, Gazi University, Ankara, Turkey
| | - Bahriye Uzun Kenan
- Department of Pediatric Nephrology, Faculty of Medicine, Gazi University, Ankara, Turkey
| | - Burcu Yazıcıoğlu
- Department of Pediatric Nephrology, Faculty of Medicine, Gazi University, Ankara, Turkey
| | - Bahar Büyükkaragöz
- Department of Pediatric Nephrology, Faculty of Medicine, Gazi University, Ankara, Turkey
| | - Kibriya Fidan
- Department of Pediatric Nephrology, Faculty of Medicine, Gazi University, Ankara, Turkey
| | - Sevcan A Bakkaloğlu
- Department of Pediatric Nephrology, Faculty of Medicine, Gazi University, Ankara, Turkey
| | - Oğuz Söylemezoğlu
- Department of Pediatric Nephrology, Faculty of Medicine, Gazi University, Ankara, Turkey
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9
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Pokidysheva EN, Redhair N, Ailsworth O, Page-McCaw P, Rollins-Smith L, Jamwal VS, Ohta Y, Bächinger HP, Murawala P, Flajnik M, Fogo AB, Abrahamson D, Hudson JK, Boudko SP, Hudson BG. Collagen IV of basement membranes: II. Emergence of collagen IV α345 enabled the assembly of a compact GBM as an ultrafilter in mammalian kidneys. J Biol Chem 2023; 299:105459. [PMID: 37977222 PMCID: PMC10746531 DOI: 10.1016/j.jbc.2023.105459] [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: 09/26/2023] [Revised: 10/28/2023] [Accepted: 10/31/2023] [Indexed: 11/19/2023] Open
Abstract
The collagen IVα345 (Col-IVα345) scaffold, the major constituent of the glomerular basement membrane (GBM), is a critical component of the kidney glomerular filtration barrier. In Alport syndrome, affecting millions of people worldwide, over two thousand genetic variants occur in the COL4A3, COL4A4, and COL4A5 genes that encode the Col-IVα345 scaffold. Variants cause loss of scaffold, a suprastructure that tethers macromolecules, from the GBM or assembly of a defective scaffold, causing hematuria in nearly all cases, proteinuria, and often progressive kidney failure. How these variants cause proteinuria remains an enigma. In a companion paper, we found that the evolutionary emergence of the COL4A3, COL4A4, COL4A5, and COL4A6 genes coincided with kidney emergence in hagfish and shark and that the COL4A3 and COL4A4 were lost in amphibians. These findings opened an experimental window to gain insights into functionality of the Col-IVα345 scaffold. Here, using tissue staining, biochemical analysis and TEM, we characterized the scaffold chain arrangements and the morphology of the GBM of hagfish, shark, frog, and salamander. We found that α4 and α5 chains in shark GBM and α1 and α5 chains in amphibian GBM are spatially separated. Scaffolds are distinct from one another and from the mammalian Col-IVα345 scaffold, and the GBM morphologies are distinct. Our findings revealed that the evolutionary emergence of the Col-IVα345 scaffold enabled the genesis of a compact GBM that functions as an ultrafilter. Findings shed light on the conundrum, defined decades ago, whether the GBM or slit diaphragm is the primary filter.
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Affiliation(s)
- Elena N Pokidysheva
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Aspirnaut, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Center for Matrix Biology, Vanderbilt University Medical Center, Nashville, Tennessee, USA.
| | - Neve Redhair
- Aspirnaut, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Octavia Ailsworth
- Aspirnaut, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Patrick Page-McCaw
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Center for Matrix Biology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Louise Rollins-Smith
- Department of Pathology Microbiology and Immunology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | | | - Yuko Ohta
- Department of Microbiology and Immunology, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | | | - Prayag Murawala
- Mount Desert Island Biological Laboratory, Bar Harbor, Maine, USA; Clinic for Kidney and Hypertension Diseases, Hannover Medical School, Hannover, Germany
| | - Martin Flajnik
- Department of Microbiology and Immunology, School of Medicine, University of Maryland, Baltimore, Maryland, USA
| | - Agnes B Fogo
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Dale Abrahamson
- Department of Cell Biology and Physiology, The Jared Grantham Kidney Institute, University of Kansas Medical Center, Kansas City, Kansas, USA
| | - Julie K Hudson
- Aspirnaut, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Sergei P Boudko
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Center for Matrix Biology, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, USA
| | - Billy G Hudson
- Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Aspirnaut, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Center for Matrix Biology, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA; Department of Biochemistry, Vanderbilt University, Nashville, Tennessee, USA; Vanderbilt-Ingram Cancer Center, Vanderbilt University, Nashville, Tennessee, USA; Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee, USA; Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA; Department of Cell and Developmental Biology, Vanderbilt University, Nashville, Tennessee, USA
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10
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Kulczyk AW. Artificial intelligence and the analysis of cryo-EM data provide structural insight into the molecular mechanisms underlying LN-lamininopathies. Sci Rep 2023; 13:17825. [PMID: 37857770 PMCID: PMC10587063 DOI: 10.1038/s41598-023-45200-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Accepted: 10/17/2023] [Indexed: 10/21/2023] Open
Abstract
Laminins (Lm) are major components of basement membranes (BM), which polymerize to form a planar lattice on cell surface. Genetic alternations of Lm affect their oligomerization patterns and lead to failures in BM assembly manifesting in a group of human disorders collectively defined as Lm N-terminal domain lamininopathies (LN-lamininopathies). We have employed a recently determined cryo-EM structure of the Lm polymer node, the basic repeating unit of the Lm lattice, along with structure prediction and modeling to systematically analyze structures of twenty-three pathogenic Lm polymer nodes implicated in human disease. Our analysis provides the detailed mechanistic explanation how Lm mutations lead to failures in Lm polymerization underlining LN-lamininopathies. We propose the new categorization scheme of LN-lamininopathies based on the insight gained from the structural analysis. Our results can help to facilitate rational drug design aiming in the treatment of Lm deficiencies.
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Affiliation(s)
- Arkadiusz W Kulczyk
- Institute for Quantitative Biomedicine, Rutgers University, 174 Frelinghuysen Road, Piscataway, NJ, 08854, USA.
- Department of Biochemistry & Microbiology, Rutgers University, 75 Lipman Drive, New Brunswick, NJ, 08901, USA.
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11
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Suzuki R, Sakakibara N, Ichikawa Y, Kitakado H, Ueda C, Tanaka Y, Okada E, Kondo A, Ishiko S, Ishimori S, Nagano C, Yamamura T, Horinouchi T, Okamoto T, Nozu K. Systematic Review of Clinical Characteristics and Genotype-Phenotype Correlation in LAMB2-Associated Disease. Kidney Int Rep 2023; 8:1811-1821. [PMID: 37705905 PMCID: PMC10496080 DOI: 10.1016/j.ekir.2023.06.019] [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: 12/06/2022] [Revised: 05/21/2023] [Accepted: 06/21/2023] [Indexed: 09/15/2023] Open
Abstract
Introduction Laminin subunit beta-2 (LAMB2)-associated disease, termed Pierson syndrome, presents with congenital nephrotic syndrome, ocular symptoms, and neuromuscular symptoms. In recent years, however, the widespread use of next-generation sequencing (NGS) has helped to discover a variety of phenotypes associated with this disease. Therefore, we conducted this systematic review. Methods A literature search of patients with LAMB2 variants was conducted, and 110 patients were investigated, including 12 of our patients. For genotype-phenotype correlation analyses, the extracted data were investigated for pathogenic variant types, the severity of nephropathy, and extrarenal symptoms. Survival analyses were also performed for the onset age of end-stage kidney disease (ESKD). Results Among all patients, 81 (78%) presented with congenital nephrotic syndrome, and 52 (55%) developed ESKD within 12 months. The median age at ESKD onset was 6.0 months. Kidney survival analysis showed that patients with biallelic truncating variants had a significantly earlier progression to ESKD than those with other variants (median age 1.2 months vs. 60.0 months, P < 0.05). Although the laminin N-terminal domain is functionally important in laminin proteins, and variants in the laminin N-terminal domain are said to result in a severe kidney phenotype such as earlier onset age and worse prognosis, there were no significant differences in onset age of nephropathy and progression to ESKD between patients with nontruncating variants located in the laminin N-terminal domain and those with variants located outside this domain. Conclusion This study revealed a diversity of LAMB2-associated diseases, characteristics of LAMB2 nephropathy, and genotype-phenotype correlations.
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Affiliation(s)
- Ryota Suzuki
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
- Department of Pediatrics, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Nana Sakakibara
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Yuta Ichikawa
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Hideaki Kitakado
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Chika Ueda
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Yu Tanaka
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Eri Okada
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Atsushi Kondo
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Shinya Ishiko
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Shingo Ishimori
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - China Nagano
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Tomohiko Yamamura
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Tomoko Horinouchi
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Takayuki Okamoto
- Department of Pediatrics, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Kandai Nozu
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
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12
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Al Riyami MS, Al Alawi I, Al Gaithi B, Al Maskari A, Al Kalbani N, Al Hashmi N, Al Balushi A, Al Shahi M, Al Saidi S, Al Bimani M, Al Hatali F, Mabillard H, Sayer JA. Genetic analysis and outcomes of Omani children with steroid-resistant nephrotic syndrome. Mol Genet Genomic Med 2023; 11:e2201. [PMID: 37204080 PMCID: PMC10496054 DOI: 10.1002/mgg3.2201] [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: 02/11/2023] [Revised: 04/28/2023] [Accepted: 05/04/2023] [Indexed: 05/20/2023] Open
Abstract
BACKGROUND Nephrotic syndrome (NS) is one of the most common kidney disorders seen by pediatric nephrologists and is defined by the presence of heavy proteinuria (>3.5 g/24 h), hypoalbuminemia (<3.5 g/dL), edema, and hyperlipidemia. Most children with NS are steroid-responsive and have a good prognosis following treatment with prednisolone. However, 10%-20% of them have steroid-resistant nephrotic syndrome (SRNS) and fail to respond to treatment. A significant proportion of these children progress to kidney failure. METHODS This retrospective study aimed to determine the underlying genetic causes of SRNS among Omani children below 13 years old, over a 15-year period and included 77 children from 50 different families. We used targeted Sanger sequencing combined with next-generation sequencing approaches to perform molecular diagnostics. RESULTS We found a high rate of underlying genetic causes of SRNS in 61 (79.2%) children with pathogenic variants in the associated genes. Most of these genetically solved SRNS patients were born to consanguineous parents and variants were in the homozygous state. Pathogenic variants in NPHS2 were the most common cause of SRNS in our study seen in 37 (48.05%) cases. Pathogenic variants in NPHS1 were also seen in 16 cases, especially in infants with congenital nephrotic syndrome (CNS). Other genetic causes identified included pathogenic variants in LAMB2, PLCE1, MYO1E, and NUP93. CONCLUSION NPHS2 and NPHS1 genetic variants were the most common inherited causes of SRNS in Omani children. However, patients with variants in several other SRNS causative genes were also identified. We recommend screening for all genes responsible for SRNS in all children who present with this phenotype, which will assist in clinical management decisions and genetic counseling for the affected families.
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Affiliation(s)
| | - Intisar Al Alawi
- Translational and Clinical Research Institute, Faculty of Medical ScienceNewcastle UniversityNewcastle upon TyneUK
- National Genetic Center, Ministry of HealthMuscatOman
| | - Badria Al Gaithi
- Pediatric Nephrology Unit, Department of Child HealthyRoyal HospitalMuscatOman
| | - Anisa Al Maskari
- Pediatric Nephrology Unit, Department of Child HealthyRoyal HospitalMuscatOman
| | - Naifain Al Kalbani
- Pediatric Nephrology Unit, Department of Child HealthyRoyal HospitalMuscatOman
| | - Nadia Al Hashmi
- Pediatric Metabolic and Genetic Disorder UnitRoyal HospitalMuscatOman
| | - Aisha Al Balushi
- Pediatric Metabolic and Genetic Disorder UnitRoyal HospitalMuscatOman
| | - Maryam Al Shahi
- Pediatric Clinical Genetic Unit, Royal Hospital, Department of Child HealthRoyal HospitalMuscatOman
| | - Suliman Al Saidi
- Pediatric Nephrology Unit, Department of Child HealthyRoyal HospitalMuscatOman
| | | | | | - Holly Mabillard
- Translational and Clinical Research Institute, Faculty of Medical ScienceNewcastle UniversityNewcastle upon TyneUK
- Renal ServicesThe Newcastle upon Tyne Hospitals NHS Foundation TrustNewcastle upon TyneUK
- Newcastle Biomedical Research Center, NIHRNewcastle upon TyneUK
| | - John A. Sayer
- Translational and Clinical Research Institute, Faculty of Medical ScienceNewcastle UniversityNewcastle upon TyneUK
- Renal ServicesThe Newcastle upon Tyne Hospitals NHS Foundation TrustNewcastle upon TyneUK
- Newcastle Biomedical Research Center, NIHRNewcastle upon TyneUK
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13
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Marcos González S, Rodrigo Calabia E, Varela I, Červienka M, Freire Salinas J, Gómez Román JJ. High Rate of Mutations of Adhesion Molecules and Extracellular Matrix Glycoproteins in Patients with Adult-Onset Focal and Segmental Glomerulosclerosis. Biomedicines 2023; 11:1764. [PMID: 37371859 DOI: 10.3390/biomedicines11061764] [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: 05/11/2023] [Revised: 06/15/2023] [Accepted: 06/18/2023] [Indexed: 06/29/2023] Open
Abstract
(1) Background: Focal and segmental glomerulosclerosis (FSGS) is a pattern of injury that results from podocyte loss in the setting of a wide variety of injurious mechanisms. These include both acquired and genetic as well as primary and secondary causes, or a combination thereof, without optimal therapy, and a high rate of patients develop end-stage renal disease (ESRD). Genetic studies have helped improve the global understanding of FSGS syndrome; thus, we hypothesize that patients with primary FSGS may have underlying alterations in adhesion molecules or extracellular matrix glycoproteins related to previously unreported mutations that may be studied through next-generation sequencing (NGS). (2) Methods: We developed an NGS panel with 29 genes related to adhesion and extracellular matrix glycoproteins. DNA was extracted from twenty-three FSGS patients diagnosed by renal biopsy; (3) Results: The average number of accumulated variants in FSGS patients was high. We describe the missense variant ITGB3c.1199G>A, which is considered pathogenic; in addition, we discovered the nonsense variant CDH1c.499G>T, which lacks a Reference SNP (rs) Report and is considered likely pathogenic. (4) Conclusions: To the best of our knowledge, this is the first account of a high rate of change in extracellular matrix glycoproteins and adhesion molecules in individuals with adult-onset FSGS. The combined effect of all these variations may result in a genotype that is vulnerable to the pathogenesis of glomerulopathy.
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Affiliation(s)
- Sara Marcos González
- Pathology Department, Marqués de Valdecilla University Hospital, Institute of Research Valdecilla (IDIVAL), 39008 Santander, Spain
| | - Emilio Rodrigo Calabia
- Nephrology Department, Marqués de Valdecilla University Hospital, 39008, University of Cantabria, 39005 Santander, Spain
| | - Ignacio Varela
- Institute of Biomedicine and Biotechnology of Cantabria (IBBTEC), 39011, University of Cantabria-CSIC, 39005 Santander, Spain
| | - Michal Červienka
- Nephrology Department, Rio Carrion General Hospital, 34005 Palencia, Spain
| | - Javier Freire Salinas
- Anatomic Pathology, Marqués de Valdecilla University Hospital, Institute of Research Valdecilla (IDIVAL), 39008 Santander, Spain
| | - José Javier Gómez Román
- Pathology Department, Marqués de Valdecilla University Hospital, Institute of Research Valdecilla (IDIVAL), School of Medicine, University of Cantabria, 39008 Santander, Spain
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14
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Sun Y, Li R, Chen Y, Yang B, Li X, Li Z, He J, Zhou Z, Li J, Guo X, Wang X, Wu Y, Zhang W, Guo G. The value of basement membrane-associated genes in the prognosis and immune regulation of glioma. Medicine (Baltimore) 2023; 102:e33935. [PMID: 37335645 DOI: 10.1097/md.0000000000033935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/21/2023] Open
Abstract
Gliomas have a high incidence rate in central nervous tumors. Although many breakthroughs have been made in the pathogenesis and treatment of glioma, the recurrence and metastasis rates of patients have not been improved based on the uniqueness of glioma. Glioma destroys the surrounding basement membrane (BM), leading to local infiltration, resulting in the corresponding clinical and neurological symptoms. Therefore, exploring the biological roles played by BM associated genes in glioma is particularly necessary for a comprehensive understanding of the biological processes of glioma and its treatment. Differential expression and univariate COX regression analyses were used to identify the basement membrane genes (BMGs) to be included in the model. LASSO regression was used to construct the BMG model. The Kaplan-Meier (KM) survival analysis model was used to assess the prognosis discrimination between training sets, validation sets, and clinical subgroups. Receiver-operating characteristic (ROC) analysis was used to test the prognostic efficacy of the model. Use calibration curves to verify the accuracy of nomograms. Gene ontology (GO), Kyoto encyclopedia of genes and genomes (KEGG), and gene set enrichment analysis (GSEA) were used to analyze the function and pathway enrichment among the model groups. ESTIMATE and other 7 algorithms including CIBERSORT were used to evaluate the immune microenvironment. "pRRophetic" was used to evaluate drug sensitivity. This study demonstrated that high-risk genes (LAMB4, MMP1, MMP7) promote glioma progression and negatively correlate with patient prognosis. In the tumor microenvironment (TME), high-risk genes have increased scores of macrophages, neutrophils, immune checkpoints, chemokines, and chemokine receptors. This study suggests that BMGs, especially high-risk-related genes, are potential sites for glioma therapy, a new prospect for comprehensively understanding the molecular mechanism of glioma.
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Affiliation(s)
- Yanqi Sun
- Department of Emergency, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
| | - Ren Li
- Department of Neurosurgery, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
| | - Yang Chen
- Department of Neurosurgery, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
| | - Biao Yang
- Department of Emergency, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
| | - Xuepeng Li
- Department of Neurosurgery, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
| | - Ziao Li
- Department of Neurosurgery, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
| | - Jianhang He
- Department of Neurosurgery, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
| | - Zihan Zhou
- Department of Neurosurgery, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
| | - Jiayu Li
- Department of Neurosurgery, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
| | - Xiaolong Guo
- Department of Neurosurgery, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
| | - Xiaogang Wang
- Department of Neurosurgery, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
| | - Yongqiang Wu
- Department of Emergency, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
| | - Wenju Zhang
- Department of Neurosurgery, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
| | - Geng Guo
- Department of Emergency, The First Hospital of Shanxi Medical University, Taiyuan, Shanxi, China
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15
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Cryo-EM reveals the molecular basis oflaminin polymerization and LN-lamininopathies. Nat Commun 2023; 14:317. [PMID: 36658135 PMCID: PMC9852560 DOI: 10.1038/s41467-023-36077-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Accepted: 01/13/2023] [Indexed: 01/20/2023] Open
Abstract
Laminin polymerization is the major step in basement membranes assembly. Its failures cause laminin N-terminal domain lamininopathies including Pierson syndrome. We have employed cryo-electron microscopy to determine a 3.7 Å structure of the trimeric laminin polymer node containing α1, β1 and γ1 subunits. The structure reveals the molecular basis of calcium-dependent formation of laminin lattice, and provides insights into polymerization defects manifesting in human disease.
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16
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Kaimori JY, Kikkawa Y, Motooka D, Namba-Hamano T, Takuwa A, Okazaki A, Kobayashi K, Tanigawa A, Kotani Y, Uno Y, Yoshimi K, Hattori K, Asahina Y, Kajimoto S, Doi Y, Oka T, Sakaguchi Y, Mashimo T, Sekiguchi K, Nakaya A, Nomizu M, Isaka Y. A heterozygous LAMA5 variant may contribute to slowly progressive, vinculin-enhanced familial FSGS and pulmonary defects. JCI Insight 2022; 7:158378. [PMID: 36173685 PMCID: PMC9746903 DOI: 10.1172/jci.insight.158378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 09/20/2022] [Indexed: 01/12/2023] Open
Abstract
The LAMA5 gene encodes laminin α5, an indispensable component of glomerular basement membrane and other types of basement membrane. A homozygous pathological variant in LAMA5 is known to cause a systemic developmental syndrome including glomerulopathy. However, the roles of heterozygous LAMA5 gene variants in human renal and systemic diseases have remained unclear. We performed whole-exome sequencing analyses of a family with slowly progressive nephropathy associated with hereditary focal segmental glomerulosclerosis, and we identified what we believe to be a novel probable pathogenic variant of LAMA5, NP_005551.3:p.Val3687Met. In vitro analyses revealed cell type-dependent changes in secretion of variant laminin α5 laminin globular 4-5 (LG4-5) domain. Heterozygous and homozygous knockin mice with a corresponding variant of human LAMA5, p.Val3687Met, developed focal segmental glomerulosclerosis-like pathology with reduced laminin α5 and increased glomerular vinculin levels, which suggested that impaired cell adhesion may underlie this glomerulopathy. We also identified pulmonary defects such as bronchial deformity and alveolar dilation. Reexaminations of the family revealed phenotypes compatible with reduced laminin α5 and increased vinculin levels in affected tissues. Thus, the heterozygous p.Val3687Met variant may cause a new syndromic nephropathy with focal segmental glomerulosclerosis through possibly defective secretion of laminin α5. Enhanced vinculin may be a useful disease marker.
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Affiliation(s)
- Jun-Ya Kaimori
- Department of Inter-Organ Communication Research in Kidney Diseases and,Department of Nephrology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Yamato Kikkawa
- Department of Clinical Biochemistry, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Daisuke Motooka
- Genome Information Research Center, Research Institute for Microbial Diseases, and,Immunology Frontier Research Center, Osaka University, Osaka, Japan
| | - Tomoko Namba-Hamano
- Department of Nephrology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Ayako Takuwa
- Immunology Frontier Research Center, Osaka University, Osaka, Japan
| | - Atsuko Okazaki
- Department of Genome Informatics, Osaka University Graduate School of Medicine, Osaka, Japan.,Diagnostics and Therapeutics of Intractable Diseases, Intractable Disease Research Center, Graduate School of Medicine, Juntendo University, Tokyo, Japan
| | - Kaori Kobayashi
- Department of Genome Informatics, Osaka University Graduate School of Medicine, Osaka, Japan.,Medical Solutions Division, NEC Corporation, Tokyo, Japan
| | | | - Yuko Kotani
- Institute of Experimental Animal Sciences and
| | | | - Kazuto Yoshimi
- Genome Editing Research and Development (R&D) Center, Osaka University Graduate School of Medicine, Osaka, Japan.,Division of Animal Genetics, Laboratory Animal Research Center, The Institute of Medical Science
| | - Koki Hattori
- Department of Nephrology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Yuta Asahina
- Department of Nephrology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Sachio Kajimoto
- Department of Nephrology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Yohei Doi
- Department of Nephrology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Tatsufumi Oka
- Department of Nephrology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Yusuke Sakaguchi
- Department of Inter-Organ Communication Research in Kidney Diseases and,Department of Nephrology, Osaka University Graduate School of Medicine, Osaka, Japan
| | - Tomoji Mashimo
- Institute of Experimental Animal Sciences and,Genome Editing Research and Development (R&D) Center, Osaka University Graduate School of Medicine, Osaka, Japan.,Division of Animal Genetics, Laboratory Animal Research Center, The Institute of Medical Science;,Division of Genome Engineering, Center for Experimental Medicine and Systems Biology, The Institute of Medical Science
| | - Kiyotoshi Sekiguchi
- Division of Matrixome Research and Application, Institute for Protein Research; and
| | - Akihiro Nakaya
- Department of Genome Informatics, Osaka University Graduate School of Medicine, Osaka, Japan.,Laboratory of Genome Data Science, Graduate School of Frontier Sciences, The University of Tokyo, Tokyo, Japan
| | - Motoyoshi Nomizu
- Department of Clinical Biochemistry, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Yoshitaka Isaka
- Department of Nephrology, Osaka University Graduate School of Medicine, Osaka, Japan
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17
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Sambharia M, Rastogi P, Thomas CP. Monogenic focal segmental glomerulosclerosis: A conceptual framework for identification and management of a heterogeneous disease. AMERICAN JOURNAL OF MEDICAL GENETICS. PART C, SEMINARS IN MEDICAL GENETICS 2022; 190:377-398. [PMID: 35894442 PMCID: PMC9796580 DOI: 10.1002/ajmg.c.31990] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 05/31/2022] [Accepted: 06/30/2022] [Indexed: 01/29/2023]
Abstract
Focal segmental glomerulosclerosis (FSGS) is not a disease, rather a pattern of histological injury occurring from a variety of causes. The exact pathogenesis has yet to be fully elucidated but is likely varied based on the type of injury and the primary target of that injury. However, the approach to treatment is often based on the degree of podocyte foot process effacement and clinical presentation without sufficient attention paid to etiology. In this regard, there are many monogenic causes of FSGS with variable presentation from nephrotic syndrome with histological features of primary podocytopathy to more modest degrees of proteinuria with limited evidence of podocyte foot process injury. It is likely that genetic causes are largely underdiagnosed, as the role and the timing of genetic testing in FSGS is not established and genetic counseling, testing options, and interpretation of genotype in the context of phenotype may be outside the scope of practice for both nephrologists and geneticists. Yet most clinicians believe that a genetic diagnosis can lead to targeted therapy, limit the use of high-dose corticosteroids as a therapeutic trial, and allow the prediction of the natural history and risk for recurrence in the transplanted kidney. In this manuscript, we emphasize that genetic FSGS is not monolithic in its presentation, opine on the importance of genetic testing and provide an algorithmic approach to deployment of genetic testing in a timely fashion when faced with a patient with FSGS.
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Affiliation(s)
- Meenakshi Sambharia
- Division of Nephrology, Department of Internal MedicineUniversity of IowaIowa CityIowaUSA
| | - Prerna Rastogi
- Department of PathologyUniversity of IowaIowa CityIowaUSA
| | - Christie P. Thomas
- Division of Nephrology, Department of Internal MedicineUniversity of IowaIowa CityIowaUSA,Department of PediatricsUniversity of IowaIowa CityIowaUSA,The Iowa Institute of Human GeneticsUniversity of IowaIowa CityIowaUSA,Medical ServiceVeterans Affairs Medical CenterIowa CityIowaUSA
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18
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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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19
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Dorval G, Servais A, Boyer O. The genetics of steroid-resistant nephrotic syndrome in children. Nephrol Dial Transplant 2022; 37:648-651. [DOI: 10.1093/ndt/gfaa221] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Indexed: 11/14/2022] Open
Affiliation(s)
- Guillaume Dorval
- Service de génétique moléculaire, Hôpital Necker - Enfants Malades, APHP, Paris, France
- Inserm U1163, Institut Imagine, Université de Paris, Paris, France
| | - Aude Servais
- Inserm U1163, Institut Imagine, Université de Paris, Paris, France
- Néphrologie et Transplantation, centre de référence MARHEA, Hôpital Necker - Enfants Malades, APHP, Paris, France
| | - Olivia Boyer
- Inserm U1163, Institut Imagine, Université de Paris, Paris, France
- Néphrologie pédiatrique, centre de référence MARHEA, centre de référence du syndrome néphrotique idiopathique de l’enfant et de l’adulte, Hôpital Necker - Enfants Malades, APHP, Paris, France
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20
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Into the Tissues: Extracellular Matrix and Its Artificial Substitutes: Cell Signalling Mechanisms. Cells 2022; 11:cells11050914. [PMID: 35269536 PMCID: PMC8909573 DOI: 10.3390/cells11050914] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 03/02/2022] [Accepted: 03/04/2022] [Indexed: 02/06/2023] Open
Abstract
The existence of orderly structures, such as tissues and organs is made possible by cell adhesion, i.e., the process by which cells attach to neighbouring cells and a supporting substance in the form of the extracellular matrix. The extracellular matrix is a three-dimensional structure composed of collagens, elastin, and various proteoglycans and glycoproteins. It is a storehouse for multiple signalling factors. Cells are informed of their correct connection to the matrix via receptors. Tissue disruption often prevents the natural reconstitution of the matrix. The use of appropriate implants is then required. This review is a compilation of crucial information on the structural and functional features of the extracellular matrix and the complex mechanisms of cell–cell connectivity. The possibilities of regenerating damaged tissues using an artificial matrix substitute are described, detailing the host response to the implant. An important issue is the surface properties of such an implant and the possibilities of their modification.
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21
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Abdollahzadeh F, Khoshdel-Rad N, Moghadasali R. Kidney development and function: ECM cannot be ignored. Differentiation 2022; 124:28-42. [DOI: 10.1016/j.diff.2022.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2021] [Revised: 01/29/2022] [Accepted: 02/04/2022] [Indexed: 11/03/2022]
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22
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Ravaglia F, Melica ME, Angelotti ML, De Chiara L, Romagnani P, Lasagni L. The Pathology Lesion Patterns of Podocytopathies: How and why? Front Cell Dev Biol 2022; 10:838272. [PMID: 35281116 PMCID: PMC8907833 DOI: 10.3389/fcell.2022.838272] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 02/07/2022] [Indexed: 11/13/2022] Open
Abstract
Podocytopathies are a group of proteinuric glomerular disorders driven by primary podocyte injury that are associated with a set of lesion patterns observed on kidney biopsy, i.e., minimal changes, focal segmental glomerulosclerosis, diffuse mesangial sclerosis and collapsing glomerulopathy. These unspecific lesion patterns have long been considered as independent disease entities. By contrast, recent evidence from genetics and experimental studies demonstrated that they represent signs of repeated injury and repair attempts. These ongoing processes depend on the type, length, and severity of podocyte injury, as well as on the ability of parietal epithelial cells to drive repair. In this review, we discuss the main pathology patterns of podocytopathies with a focus on the cellular and molecular response of podocytes and parietal epithelial cells.
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Affiliation(s)
| | - Maria Elena Melica
- Department of Experimental and Clinical Biomedical Sciences “Mario Serio”, University of Florence, Florence, Italy
| | - Maria Lucia Angelotti
- Department of Experimental and Clinical Biomedical Sciences “Mario Serio”, University of Florence, Florence, Italy
| | - Letizia De Chiara
- Department of Experimental and Clinical Biomedical Sciences “Mario Serio”, University of Florence, Florence, Italy
| | - Paola Romagnani
- Department of Experimental and Clinical Biomedical Sciences “Mario Serio”, University of Florence, Florence, Italy
- Nephrology Unit, Meyer Children’s Hospital, Florence, Italy
| | - Laura Lasagni
- Department of Experimental and Clinical Biomedical Sciences “Mario Serio”, University of Florence, Florence, Italy
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23
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Ramdas S, Beeson D. Congenital myasthenic syndromes: where do we go from here? Neuromuscul Disord 2021; 31:943-954. [PMID: 34736634 DOI: 10.1016/j.nmd.2021.07.400] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 07/22/2021] [Accepted: 07/27/2021] [Indexed: 11/27/2022]
Abstract
Congenital myasthenia syndromes are rare but often treatable conditions affecting neuromuscular transmission. They result from loss or impaired function of one of a number of proteins secondary to a genetic defect. An estimate of the prevalence in the UK gave 9.2 cases per million, however, this is likely an underestimate since the adoption of next generation sequencing for diagnosis away from specialist centres is enhancing the 'pick up' rate. Next generation sequencing has helped identify a series of novel genes that harbour mutations causative for congenital myasthenic syndrome that include not only genes that encode proteins specifically expressed at the neuromuscular junction but also those that are ubiquitously expressed. The list of genes harbouring disease-causing mutations for congenital myasthenic syndrome continues to expand and is now over 30, but with many of the newly identified genes it is increasingly being recognised that abnormal neuromuscular transmission is only one component of a multifaceted phenotype in which muscle, the central nervous system, and other organs may also be affected. Treatment can be tailored to the underlying molecular mechanism for impaired neuromuscular transmission but treating the more complex multifaceted disorders and will require development of new therapies.
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Affiliation(s)
- Sithara Ramdas
- MDUK Neuromuscular centre, Children's Hospital, John Radcliffe Hospital, Oxford, OX3 9DU, UK
| | - David Beeson
- Neurosciences Group, Weatherall Institute of Molecular Medicine, The John Radcliffe, Oxford OX3 9DS, UK.
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24
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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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25
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Taniguchi Y, Nagano C, Sekiguchi K, Tashiro A, Sugawara N, Sakaguchi H, Umeda C, Aoto Y, Ishiko S, Rossanti R, Sakakibara N, Horinouchi T, Yamamura T, Kondo A, Nagai S, Nagase H, Iijima K, Miner JH, Nozu K. Clear Evidence of LAMA5 Gene Biallelic Truncating Variants Causing Infantile Nephrotic Syndrome. KIDNEY360 2021; 2:1968-1978. [PMID: 35419533 PMCID: PMC8986055 DOI: 10.34067/kid.0004952021] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 10/15/2021] [Indexed: 02/04/2023]
Abstract
Background Pathogenic variants in single genes encoding podocyte-associated proteins have been implicated in about 30% of steroid-resistant nephrotic syndrome (SRNS) patients in children. However, LAMA5 gene biallelic variants have been identified in only seven patients so far, and most are missense variants of unknown significance. Furthermore, no functional analysis had been conducted for all but one of these variants. Here, we report three patients with LAMA5 gene biallelic truncating variants manifesting infantile nephrotic syndrome, and one patient with SRNS with biallelic LAMA5 missense variants. Methods We conducted comprehensive gene screening of Japanese patients with severe proteinuria. With the use of targeted next-generation sequencing, 62 podocyte-related genes were screened in 407 unrelated patients with proteinuria. For the newly discovered LAMA5 variants, we conducted in vitro heterotrimer formation assays. Results Biallelic truncating variants in the LAMA5 gene (NM_005560) were detected in three patients from two families. All patients presented with proteinuria within 6 months of age. Patients 1 and 2 were siblings possessing a nonsense variant (c.9232C>T, p.[Arg3078*]) and a splice site variant (c.1282 + 1G>A) that led to exon 9 skipping and a frameshift. Patient 3 had a remarkable irregular contour of the glomerular basement membrane. She was subsequently found to have a nonsense variant (c.8185C>T, p.[Arg2720*]) and the same splice site variant in patients 1 and 2. By in vitro heterotrimer formation assays, both truncating variants produced smaller laminin α5 proteins that nevertheless formed trimers with laminin β1 and γ1 chains. Patient 4 showed SRNS at the age of 8 years, and carried compound heterozygous missense variants (c.1493C>T, p.[Ala498Val] and c.8399G>A, p.[Arg2800His]). Conclusions Our patients showed clear evidence of biallelic LAMA5 truncating variants causing infantile nephrotic syndrome. We also discerned the clinical and pathologic characteristics observed in LAMA5-related nephropathy. LAMA5 variant screening should be performed in patients with congenital/infantile nephrotic syndrome.
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Affiliation(s)
- Yukimasa Taniguchi
- Division of Matrixome Research and Application, Osaka University, Osaka, Japan
| | - China Nagano
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Kiyotoshi Sekiguchi
- Division of Matrixome Research and Application, Osaka University, Osaka, Japan
| | - Atsushi Tashiro
- Department of Pediatrics, Japan Community Health Care Organization Chukyo Hospital, Aichi, Japan
| | - Noriko Sugawara
- Department of Pediatrics, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Haruhide Sakaguchi
- Department of Pediatrics, The Jikei University School of Medicine, Tokyo, Japan
| | - Chisato Umeda
- Department of Pediatrics, The Jikei University School of Medicine, Tokyo, Japan
| | - Yuya Aoto
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Shinya Ishiko
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Rini Rossanti
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Nana Sakakibara
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Tomoko Horinouchi
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Tomohiko Yamamura
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Atsushi Kondo
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Sadayuki Nagai
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Hiroaki Nagase
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Kazumoto Iijima
- Hyogo Prefectural Kobe Children’s Hospital, Hyogo, Japan,Department of Advanced Pediatric Medicine, Kobe University Graduate School of Medicine, Hyogo, Japan
| | - Jeffrey H. Miner
- Division of Nephrology, Washington University School of Medicine, St. Louis, Missouri
| | - Kandai Nozu
- Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
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26
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Shaw L, Sugden CJ, Hamill KJ. Laminin Polymerization and Inherited Disease: Lessons From Genetics. Front Genet 2021; 12:707087. [PMID: 34456976 PMCID: PMC8388930 DOI: 10.3389/fgene.2021.707087] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Accepted: 07/13/2021] [Indexed: 01/13/2023] Open
Abstract
The laminins (LM) are a family of basement membranes glycoproteins with essential structural roles in supporting epithelia, endothelia, nerves and muscle adhesion, and signaling roles in regulating cell migration, proliferation, stem cell maintenance and differentiation. Laminins are obligate heterotrimers comprised of α, β and γ chains that assemble intracellularly. However, extracellularly these heterotrimers then assemble into higher-order networks via interaction between their laminin N-terminal (LN) domains. In vitro protein studies have identified assembly kinetics and the structural motifs involved in binding of adjacent LN domains. The physiological importance of these interactions has been identified through the study of pathogenic point mutations in LN domains that lead to syndromic disorders presenting with phenotypes dependent on which laminin gene is mutated. Genotype-phenotype comparison between knockout and LN domain missense mutations of the same laminin allows inferences to be drawn about the roles of laminin network assembly in terms of tissue function. In this review, we will discuss these comparisons in terms of laminin disorders, and the therapeutic options that understanding these processes have allowed. We will also discuss recent findings of non-laminin mediators of laminin network assembly and their implications in terms of basement membrane structure and function.
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Affiliation(s)
| | | | - Kevin J. Hamill
- Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, United Kingdom
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27
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Sobieszczańska-Droździel A, Grenda R, Lipska-Ziętkiewicz BS, Korolczuk A, Jarmużek W, Sikora P. Five-Year Follow-Up and Successful Kidney Transplantation in a Girl with a Severe Phenotype of Pierson Syndrome. Nephron Clin Pract 2021; 145:579-584. [PMID: 34058744 DOI: 10.1159/000516247] [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: 10/20/2020] [Accepted: 03/22/2021] [Indexed: 11/19/2022] Open
Abstract
Pierson syndrome (PIERSS) is a rare autosomal recessive disorder characterized by the combination of congenital nephrotic syndrome (CNS) and extrarenal symptoms including ocular malformations and neurodevelopmental deficits. PIERSS is caused by biallelic pathogenic variants in the LAMB2 gene leading to the defects of β2-laminin, the protein mainly expressed in the glomerular basement membrane, ocular structures, and neuromuscular junctions. Severe complications of PIERSS lead to the fatal outcome in early childhood in majority of the cases. We report a case of 5-year-old girl with severe phenotype of PIERSS caused by biallelic functional null variants of the LAMB2 gene. Due to consequences of CNS, the patient required bilateral nephrectomy and peritoneal dialysis since early infancy. The course was additionally complicated by tubulopathy, life-threatening infections, severe hypertension, erythropoietin-resistant anemia, generalized muscular hypotonia, neurogenic bladder, profound neurodevelopmental delay, epilepsy, gastrointestinal problems, secondary hypothyroidism, and necessity of repeated ocular surgery due to microcoria, cataract, and nystagmus. Due to multidisciplinary efforts, at the age of 4 years, the kidney transplantation was possible. Currently, the renal graft has an excellent function; however, the girl presents severe neurodevelopmental delay. The report presents a unique long-term follow-up of severe PIERSS with a few new phenotypical findings. It highlights the clinical problems and challenges in management of this rare condition.
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Affiliation(s)
| | - Ryszard Grenda
- Department of Nephrology, Kidney Transplantation and Hypertension, Children's Memorial Health Institute, Warsaw, Poland
| | - Beata Stefania Lipska-Ziętkiewicz
- Centre for Rare Diseases, Medical University of Gdansk, Gdańsk, Poland.,Department of Biology and Medical Genetics, Clinical Genetics Unit, Medical University of Gdansk, Gdańsk, Poland
| | - Agnieszka Korolczuk
- Department of Clinical Pathomorphology, Medical University of Lublin, Lublin, Poland
| | - Wioletta Jarmużek
- Department of Nephrology, Kidney Transplantation and Hypertension, Children's Memorial Health Institute, Warsaw, Poland
| | - Przemyslaw Sikora
- Department of Pediatric Nephrology, Medical University of Lublin, Lublin, Poland
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28
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Organization of the laminin polymer node. Matrix Biol 2021; 98:49-63. [PMID: 34029691 DOI: 10.1016/j.matbio.2021.05.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 05/14/2021] [Accepted: 05/15/2021] [Indexed: 12/13/2022]
Abstract
Laminin polymerization is a key step of basement membrane assembly that depends on the binding of α, β and γ N-terminal LN domains to form a polymer node. Nodal assembly can be divided into two steps consisting of β- and γ-LN dimerization followed by calcium-dependent addition of the α-LN domain. The assembly and structural organization of laminin-111 LN-LEa segments was examined by size-exclusion chromatography (SEC) and electron microscopy. Triskelion-like structures were observed in negatively-stained images of purified α1/β1/γ1 LN-LEa trimers. Image averaging of these revealed a heel-to-toe organization of the LN domains with angled outward projections of the LEa stem-like domains. A series of single-amino acid substitutions was introduced into the polymerization faces of the α1, β1 and γ1 LN domains followed by SEC analysis to distinguish between loss of β-γ mediated dimerization and loss of α-dependent trimerization (with intact β-γ dimers). Dimer-blocking mutations were confined to the γ1-toe and the β1-heel, whereas the trimer-only-blocking mutations mapped to the γ1-heel, β1-toe and the α1-toe and heel. Thus, in the polymer node the γ1-toe pairs with the β1-heel, the β1-toe pairs with the α1-heel, and the α1-toe pairs with the γ1-heel.
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29
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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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30
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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: 3] [Impact Index Per Article: 1.0] [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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31
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Kikkawa Y, Hashimoto T, Takizawa K, Urae S, Masuda H, Matsunuma M, Yamada Y, Hamada K, Nomizu M, Liapis H, Hisano M, Akioka Y, Miura K, Hattori M, Miner JH, Harita Y. Laminin β2 variants associated with isolated nephropathy that impact matrix regulation. JCI Insight 2021; 6:145908. [PMID: 33749661 PMCID: PMC8026196 DOI: 10.1172/jci.insight.145908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 02/10/2021] [Indexed: 11/17/2022] Open
Abstract
Mutations in LAMB2, encoding laminin β2, cause Pierson syndrome and occasionally milder nephropathy without extrarenal abnormalities. The most deleterious missense mutations that have been identified affect primarily the N-terminus of laminin β2. On the other hand, those associated with isolated nephropathy are distributed across the entire molecule, and variants in the β2 LEa-LF-LEb domains are exclusively found in cases with isolated nephropathy. Here we report the clinical features of mild isolated nephropathy associated with 3 LAMB2 variants in the LEa-LF-LEb domains (p.R469Q, p.G699R, and p.R1078C) and their biochemical characterization. Although Pierson syndrome missense mutations often inhibit laminin β2 secretion, the 3 recombinant variants were secreted as efficiently as WT. However, the β2 variants lost pH dependency for heparin binding, resulting in aberrant binding under physiologic conditions. This suggests that the binding of laminin β2 to negatively charged molecules is involved in glomerular basement membrane (GBM) permselectivity. Moreover, the excessive binding of the β2 variants to other laminins appears to lead to their increased deposition in the GBM. Laminin β2 also serves as a potentially novel cell-adhesive ligand for integrin α4β1. Our findings define biochemical functions of laminin β2 variants influencing glomerular filtration that may underlie the pathogenesis of isolated nephropathy caused by LAMB2 abnormalities.
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Affiliation(s)
- Yamato Kikkawa
- Department of Clinical Biochemistry, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Taeko Hashimoto
- Department of Pediatrics, Yamagata University School of Medicine, Yamagata, Japan.,Department of Pediatric Nephrology, School of Medicine, Tokyo Women's Medical University, Tokyo, Japan
| | - Keiichi Takizawa
- Department of Pediatrics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Seiya Urae
- Department of Pediatrics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Haruka Masuda
- Department of Clinical Biochemistry, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Masumi Matsunuma
- Department of Clinical Biochemistry, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Yuji Yamada
- Department of Clinical Biochemistry, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Keisuke Hamada
- Department of Clinical Biochemistry, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Motoyoshi Nomizu
- Department of Clinical Biochemistry, Tokyo University of Pharmacy and Life Sciences, Tokyo, Japan
| | - Helen Liapis
- Department of Pathology and Immunology and Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Masataka Hisano
- Department of Nephrology, Chiba Children's Hospital, Chiba, Japan
| | - Yuko Akioka
- Department of Pediatric Nephrology, School of Medicine, Tokyo Women's Medical University, Tokyo, Japan.,Department of Pediatrics, Faculty of Medicine, Saitama Medical University, Saitama, Japan
| | - Kenichiro Miura
- Department of Pediatric Nephrology, School of Medicine, Tokyo Women's Medical University, Tokyo, Japan
| | - Motoshi Hattori
- Department of Pediatric Nephrology, School of Medicine, Tokyo Women's Medical University, Tokyo, Japan
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, and Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Yutaka Harita
- Department of Pediatrics, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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32
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Magliyah MS, Alsulaiman SM. Development of neovascular glaucoma after intraocular surgery in Pierson syndrome. Ophthalmic Genet 2021; 42:317-319. [PMID: 33554690 DOI: 10.1080/13816810.2021.1881982] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Purpose: To report a patient with Pierson syndrome who presented with neovascular glaucoma (NVG) after cataract surgery.Methods: Retrospective case report.Results: A 17-year old monocular female presented with sudden onset of pain and decreased vision in the right eye. On examination, she had intraocular pressure (IOP) of 50 mmHg, aggressive iris neovascularization (NVI) and 3-piece IOL. Fundus examination revealed pale disc with tessellated fundus and parapapillary atrophy. Vascular arcades were vertically stretched with avascular ischemic retina starting from the near periphery. Macula appeared thin and atrophic. An intravitreal injection of 0.05 mg/0.1 ml bevacizumab was given to the right eye followed by Ahmed glaucoma valve (AGV) implantation. Assessment of her brother revealed similar posterior segment changes. A subsequent urine analysis showed proteinuria and high albumin to creatinine ratio. Next-generation sequencing for LAMB2 gene revealed a homozygous c.4573 + 1 G > A variant confirming the diagnosis of Pierson syndrome.Conclusion: This case expands our knowledge on retinal ischemia in the setting of Pierson syndrome. Close monitoring after intraocular surgery is recommended to look for the development of NVG.
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Affiliation(s)
- Moustafa S Magliyah
- Vitreoretinal Division, King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia.,Ophthalmology Department, Prince Mohammed Medical City, AlJouf, Saudi Arabia
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An extremely mild clinical course in a case with LAMB2-associated nephritis diagnosed with next-generation sequencing. CEN Case Rep 2021; 10:359-363. [PMID: 33476040 DOI: 10.1007/s13730-021-00574-1] [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: 07/25/2020] [Accepted: 12/29/2020] [Indexed: 10/22/2022] Open
Abstract
Biallelic pathogenic variants in the laminin β2 (LAMB2) gene, which encodes laminin β2, are associated with Pierson syndrome characterized by a congenital nephrotic syndrome that rapidly progresses to end-stage renal disease, distinct ocular maldevelopment with bilateral microcoria, and neurodevelopmental deficits. However, the phenotypic spectrum of LAMB2-associated disorder is broader than expected, and cases with milder phenotypes such as isolated congenital or infantile nephrotic syndrome have also been reported. We report a patient with LAMB2-associated renal disorder showing an extremely mild phenotype. A 5-year-old girl presented with asymptomatic proteinuria and hematuria detected by urinalysis screening. She had been previously healthy without any additional renal symptoms. The serum albumin and creatinine levels were normal. Renal biopsy revealed minor glomerular abnormalities with occasional focal mesangial proliferation. Electron microscopy showed no structural changes in the glomerular basement membrane. Targeted sequencing of podocyte-related genes using next-generation sequencing was performed. As a result, previously reported biallelic pathogenic variants of the truncating variant (c.5073_5076dupCCAG) and a splice site variant (c.3797 + 5G > A) in the LAMB2 gene were detected, and the patient was diagnosed with LAMB2-associated renal disorder. Interestingly, a previously reported case with this splicing variant also showed an atypically mild phenotype. We suggest that clinicians should consider LAMB2-associated nephritis as an important differential diagnosis in children with asymptomatic proteinuria and microscopic hematuria if there is no structural change in the glomerular basement membrane. A comprehensive gene-screening system using next-generation sequencing is useful for diagnosing these atypical cases with isolated urine abnormalities.
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34
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Rodríguez Cruz PM, Cossins J, Beeson D, Vincent A. The Neuromuscular Junction in Health and Disease: Molecular Mechanisms Governing Synaptic Formation and Homeostasis. Front Mol Neurosci 2020; 13:610964. [PMID: 33343299 PMCID: PMC7744297 DOI: 10.3389/fnmol.2020.610964] [Citation(s) in RCA: 73] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Accepted: 10/30/2020] [Indexed: 12/28/2022] Open
Abstract
The neuromuscular junction (NMJ) is a highly specialized synapse between a motor neuron nerve terminal and its muscle fiber that are responsible for converting electrical impulses generated by the motor neuron into electrical activity in the muscle fibers. On arrival of the motor nerve action potential, calcium enters the presynaptic terminal, which leads to the release of the neurotransmitter acetylcholine (ACh). ACh crosses the synaptic gap and binds to ACh receptors (AChRs) tightly clustered on the surface of the muscle fiber; this leads to the endplate potential which initiates the muscle action potential that results in muscle contraction. This is a simplified version of the events in neuromuscular transmission that take place within milliseconds, and are dependent on a tiny but highly structured NMJ. Much of this review is devoted to describing in more detail the development, maturation, maintenance and regeneration of the NMJ, but first we describe briefly the most important molecules involved and the conditions that affect their numbers and function. Most important clinically worldwide, are myasthenia gravis (MG), the Lambert-Eaton myasthenic syndrome (LEMS) and congenital myasthenic syndromes (CMS), each of which causes specific molecular defects. In addition, we mention the neurotoxins from bacteria, snakes and many other species that interfere with neuromuscular transmission and cause potentially fatal diseases, but have also provided useful probes for investigating neuromuscular transmission. There are also changes in NMJ structure and function in motor neuron disease, spinal muscle atrophy and sarcopenia that are likely to be secondary but might provide treatment targets. The NMJ is one of the best studied and most disease-prone synapses in the nervous system and it is amenable to in vivo and ex vivo investigation and to systemic therapies that can help restore normal function.
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Affiliation(s)
- Pedro M Rodríguez Cruz
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom.,Neurosciences Group, Weatherall Institute of Molecular Medicine, University of Oxford, The John Radcliffe Hospital, Oxford, United Kingdom
| | - Judith Cossins
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom.,Neurosciences Group, Weatherall Institute of Molecular Medicine, University of Oxford, The John Radcliffe Hospital, Oxford, United Kingdom
| | - David Beeson
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom.,Neurosciences Group, Weatherall Institute of Molecular Medicine, University of Oxford, The John Radcliffe Hospital, Oxford, United Kingdom
| | - Angela Vincent
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom.,Neurosciences Group, Weatherall Institute of Molecular Medicine, University of Oxford, The John Radcliffe Hospital, Oxford, United Kingdom
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35
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Pértille F, Ibelli AMG, Sharif ME, Poleti MD, Fröhlich AS, Rezaei S, Ledur MC, Jensen P, Guerrero-Bosagna C, Coutinho LL. Putative Epigenetic Biomarkers of Stress in Red Blood Cells of Chickens Reared Across Different Biomes. Front Genet 2020; 11:508809. [PMID: 33240310 PMCID: PMC7667380 DOI: 10.3389/fgene.2020.508809] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 09/11/2020] [Indexed: 12/19/2022] Open
Abstract
Production animals are constantly subjected to early adverse environmental conditions that influence the adult phenotype and produce epigenetic effects. CpG dinucleotide methylation in red blood cells (RBC) could be a useful epigenetic biomarker to identify animals subjected to chronic stress in the production environment. Here we compared a reduced fraction of the RBC methylome of chickens exposed to social isolation to non-exposed. These experiments were performed in two different locations: Brazil and Sweden. The aim was to identify stress-associated DNA methylation profiles in RBC across these populations, in spite of the variable conditions to which birds are exposed in each facility and their different lineages. Birds were increasingly exposed to a social isolation treatment, combined with food and water deprivation, at random periods of the day from weeks 1-4 after hatching. We then collected the RBC DNA from individuals and compared a reduced fraction of their methylome between the experimental groups using two bioinformatic approaches to identify differentially methylated regions (DMRs): one using fixed-size windows and another that preselected differential peaks with MACS2. Three levels of significance were used (P ≤ 0.05, P ≤ 0.005, and P ≤ 0.0005) to identify DMRs between experimental groups, which were then used for different analyses. With both of the approaches more DMRs reached the defined significance thresholds in BR individuals compared to SW. However, more DMRs had higher fold change values in SW compared to BR individuals. Interestingly, ChrZ was enriched above expectancy for the presence of DMRs. Additionally, when analyzing the locations of these DMRs in relation to the transcription starting site (TSS), we found three peaks with high DMR presence: 10 kb upstream, the TSS itself, and 20-40 kb downstream. Interestingly, these peaks had DMRs with a high presence (>50%) of specific transcription factor binding sites. Three overlapping DMRs were found between the BR and SW population using the most relaxed p-value (P ≤ 0.05). With the most stringent p-value (P ≤ 0.0005), we found 7 and 4 DMRs between treatments in the BR and SW populations, respectively. This study is the first approximation to identify epigenetic biomarkers of long-term exposure to stress in different lineages of production animals.
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Affiliation(s)
- Fábio Pértille
- Animal Biotechnology Laboratory, Animal Science and Pastures Department, University of São Paulo (USP)/"Luiz de Queiroz" College of Agriculture (ESALQ), Piracicaba, Brazil.,Avian Behavioural Genomics and Physiology Group, IFM Biology, Linköping University, Linköping, Sweden
| | | | - Maj El Sharif
- Avian Behavioural Genomics and Physiology Group, IFM Biology, Linköping University, Linköping, Sweden
| | - Mirele Daiana Poleti
- Animal Science Program, Faculty of Animal Science and Food Engineering (FZEA), University of São Paulo (USP), Pirassununga, Brazil
| | - Anna Sophie Fröhlich
- Avian Behavioural Genomics and Physiology Group, IFM Biology, Linköping University, Linköping, Sweden
| | - Shiva Rezaei
- Avian Behavioural Genomics and Physiology Group, IFM Biology, Linköping University, Linköping, Sweden
| | | | - Per Jensen
- Avian Behavioural Genomics and Physiology Group, IFM Biology, Linköping University, Linköping, Sweden
| | - Carlos Guerrero-Bosagna
- Avian Behavioural Genomics and Physiology Group, IFM Biology, Linköping University, Linköping, Sweden.,Evolutionary Biology Centre, Department of Organismal Biology, Uppsala University, Uppsala, Sweden
| | - Luiz Lehmann Coutinho
- Animal Biotechnology Laboratory, Animal Science and Pastures Department, University of São Paulo (USP)/"Luiz de Queiroz" College of Agriculture (ESALQ), Piracicaba, Brazil
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36
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AlTaisan A, Magliyah M, Abouammoh MA, Taskintuna I, Alzahrani Y, Chang E, Alsulaiman SM. Posterior Segment Characterization in Children With Pierson Syndrome. Ophthalmic Surg Lasers Imaging Retina 2020; 51:618-627. [DOI: 10.3928/23258160-20201104-03] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 09/10/2020] [Indexed: 01/25/2023]
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37
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Lipska-Ziętkiewicz BS, Ozaltin F, Hölttä T, Bockenhauer D, Bérody S, Levtchenko E, Vivarelli M, Webb H, Haffner D, Schaefer F, Boyer O. Genetic aspects of congenital nephrotic syndrome: a consensus statement from the ERKNet-ESPN inherited glomerulopathy working group. Eur J Hum Genet 2020; 28:1368-1378. [PMID: 32467597 PMCID: PMC7608398 DOI: 10.1038/s41431-020-0642-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2019] [Revised: 03/03/2020] [Accepted: 03/10/2020] [Indexed: 01/23/2023] Open
Abstract
Congenital nephrotic syndrome (CNS) is a heterogeneous group of disorders presenting with massive proteinuria within the first 3 months of life almost inevitably leading to end-stage kidney disease. The Work Group for the European Reference Network for Kidney Diseases (ERKNet) and the European Society for Pediatric Nephrology (ESPN) has developed consensus statement on genetic aspects of CNS diagnosis and management. The presented expert opinion recommends genetic diagnostics as the key diagnostic test to be ordered already during the initial evaluation of the patient, discusses which phenotyping workup should be performed and presents known genotype-phenotype correlations.
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Affiliation(s)
- Beata Stefania Lipska-Ziętkiewicz
- Clinical Genetics Unit, Department of Biology and Medical Genetics, Medical University of Gdańsk, Gdańsk, Poland.
- Centre for Rare Diseases, Medical University of Gdańsk, Gdańsk, Poland.
| | - Fatih Ozaltin
- Department of Pediatric Nephrology and Nephrogenetics Laboratory, Hacettepe University Faculty of Medicine, Ankara, Turkey.
| | - Tuula Hölttä
- Department of Pediatric Nephrology and Transplantation, The New Children's Hospital, HUS Helsinki University Hospital, Helsinki, Finland
| | - Detlef Bockenhauer
- UCL Department of Renal Medicine and Renal Unit, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Sandra Bérody
- Department of Pediatric Nephrology, Reference Center for Hereditary Kidney Diseases (MARHEA), Necker Hospital, APHP, 75015, Paris, France
| | - Elena Levtchenko
- Division of Pediatric Nephrology, Department of Pediatrics, University Hospitals Leuven; Department of Development & Regeneration, University of Leuven, Leuven, Belgium
| | - Marina Vivarelli
- Division of Nephrology and Dialysis, Department of Pediatric Subspecialties, Bambino Gesù Pediatric Hospital and Research Center, Rome, Italy
| | - Hazel Webb
- UCL Department of Renal Medicine and Renal Unit, Great Ormond Street Hospital for Children NHS Foundation Trust, London, UK
| | - Dieter Haffner
- Department of Pediatric Kidney, Liver and Metabolic Diseases, Hannover Medical School Children's Hospital, Hannover, Germany
- Center for Congenital Kidney Diseases, Center for Rare Diseases, Hannover Medical School, Hannover, Germany
| | - Franz Schaefer
- Division of Pediatric Nephrology, Center for Pediatrics and Adolescent Medicine, Heidelberg, Germany.
| | - Olivia Boyer
- Department of Pediatric Nephrology, Reference Center for Hereditary Kidney Diseases (MARHEA), Necker Hospital, APHP, 75015, Paris, France
- Laboratory of Hereditary Kidney Diseases, Imagine Institute, INSERM, Paris Descartes University, U1163, Paris, France
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38
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Randles MJ, Lausecker F, Humphries JD, Byron A, Clark SJ, Miner JH, Zent R, Humphries MJ, Lennon R. Basement membrane ligands initiate distinct signalling networks to direct cell shape. Matrix Biol 2020; 90:61-78. [PMID: 32147508 PMCID: PMC7327512 DOI: 10.1016/j.matbio.2020.02.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2019] [Revised: 02/29/2020] [Accepted: 02/29/2020] [Indexed: 01/09/2023]
Abstract
Cells have evolved mechanisms to sense the composition of their adhesive microenvironment. Although much is known about general mechanisms employed by adhesion receptors to relay signals between the extracellular environment and the cytoskeleton, the nuances of ligand-specific signalling remain undefined. Here, we investigated how glomerular podocytes, and four other basement membrane-associated cell types, respond morphologically to different basement membrane ligands. We defined the composition of the respective adhesion complexes using mass spectrometry-based proteomics. On type IV collagen, all epithelial cell types adopted a round morphology, with a single lamellipodium and large adhesion complexes rich in actin-binding proteins. On laminin (511 or 521), all cell types attached to a similar degree but were polygonal in shape with small adhesion complexes enriched in endocytic and microtubule-binding proteins. Consistent with their distinctive morphologies, cells on type IV collagen exhibited high Rac1 activity, while those on laminin had elevated PKCα. Perturbation of PKCα was able to interchange morphology consistent with a key role for this pathway in matrix ligand-specific signalling. Therefore, this study defines the switchable basement membrane adhesome and highlights two key signalling pathways within the systems that determine distinct cell morphologies. Proteomic data are availableviaProteomeXchange with identifier PXD017913.
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Affiliation(s)
- Michael J Randles
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Franziska Lausecker
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Jonathan D Humphries
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Adam Byron
- Cancer Research UK Edinburgh Centre, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK
| | - Simon J Clark
- Universitäts-Augenklinik Tübingen, Eberhard Karls University of Tübingen, Germany; The Lydia Becker Institute of Immunology and Inflammation, Faculty of Biology Medicine and Health, The University of Manchester, Manchester, UK
| | - Jeffrey H Miner
- Renal Division, Washington University School of Medicine, Saint Louis, MO, USA
| | - Roy Zent
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Martin J Humphries
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK
| | - Rachel Lennon
- Wellcome Centre for Cell-Matrix Research, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology Medicine and Health, The University of Manchester, Manchester Academic Health Science Centre, Manchester, UK; Department of Paediatric Nephrology, Royal Manchester Children's Hospital, Manchester University Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK.
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39
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Mittal P, Kaur A, Kumar J, Kumar P. Cystic kidneys in a neonate: do not forget to examine pupils. BMJ Case Rep 2020; 13:13/7/e236517. [PMID: 32616536 DOI: 10.1136/bcr-2020-236517] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Affiliation(s)
- Piyush Mittal
- Pediatrics, Post Graduate Institute of Medical Education and Research, Chandigarh, India
| | - Amrit Kaur
- Pediatrics, Post Graduate Institute of Medical Education and Research, Chandigarh, India
| | - Jogender Kumar
- Pediatrics, Post Graduate Institute of Medical Education and Research, Chandigarh, India
| | - Praveen Kumar
- Pediatrics, Post Graduate Institute of Medical Education and Research, Chandigarh, India
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40
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The congenital myasthenic syndromes: expanding genetic and phenotypic spectrums and refining treatment strategies. Curr Opin Neurol 2020; 32:696-703. [PMID: 31361628 PMCID: PMC6735524 DOI: 10.1097/wco.0000000000000736] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Congenital myasthenic syndromes (CMS) are a group of heterogeneous inherited disorders caused by mutations in genes encoding proteins whose function is essential for the integrity of neuromuscular transmission. This review updates the reader on the expanding phenotypic spectrum and suggested improved treatment strategies.
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41
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Butt L, Unnersjö-Jess D, Höhne M, Edwards A, Binz-Lotter J, Reilly D, Hahnfeldt R, Ziegler V, Fremter K, Rinschen MM, Helmstädter M, Ebert LK, Castrop H, Hackl MJ, Walz G, Brinkkoetter PT, Liebau MC, Tory K, Hoyer PF, Beck BB, Brismar H, Blom H, Schermer B, Benzing T. A molecular mechanism explaining albuminuria in kidney disease. Nat Metab 2020; 2:461-474. [PMID: 32694662 DOI: 10.1038/s42255-020-0204-y] [Citation(s) in RCA: 85] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/21/2019] [Accepted: 04/07/2020] [Indexed: 01/18/2023]
Abstract
Mammalian kidneys constantly filter large amounts of liquid, with almost complete retention of albumin and other macromolecules in the plasma. Breakdown of the three-layered renal filtration barrier results in loss of albumin into urine (albuminuria) across the wall of small renal capillaries, and is a leading cause of chronic kidney disease. However, exactly how the renal filter works and why its permeability is altered in kidney diseases is poorly understood. Here we show that the permeability of the renal filter is modulated through compression of the capillary wall. We collect morphometric data prior to and after onset of albuminuria in a mouse model equivalent to a human genetic disease affecting the renal filtration barrier. Combining quantitative analyses with mathematical modelling, we demonstrate that morphological alterations of the glomerular filtration barrier lead to reduced compressive forces that counteract filtration pressure, thereby resulting in capillary dilatation, and ultimately albuminuria. Our results reveal distinct functions of the different layers of the filtration barrier and expand the molecular understanding of defective renal filtration in chronic kidney disease.
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Affiliation(s)
- Linus Butt
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - David Unnersjö-Jess
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
- Royal Institute of Technology, Stockholm, Sweden
| | - Martin Höhne
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Aurelie Edwards
- Department of Biomedical Engineering, Boston University, Boston, MA, USA
| | - Julia Binz-Lotter
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Dervla Reilly
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Robert Hahnfeldt
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Vera Ziegler
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Katharina Fremter
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Markus M Rinschen
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
- Center for Mass Spectrometry and Metabolomics, The Scripps Research Institute, La Jolla, CA, USA
| | - Martin Helmstädter
- Department of Medicine IV, Medical Center - University of Freiburg, Faculty of Medicine, and Signalling Research Centres BIOSS and CIBSS, University of Freiburg,, Freiburg, Germany
| | - Lena K Ebert
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Hayo Castrop
- Institute of Physiology, University of Regensburg, Regensburg, Germany
| | - Matthias J Hackl
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Gerd Walz
- Department of Medicine IV, Medical Center - University of Freiburg, Faculty of Medicine, and Signalling Research Centres BIOSS and CIBSS, University of Freiburg,, Freiburg, Germany
| | - Paul T Brinkkoetter
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Max C Liebau
- Department of Pediatrics and Center for Molecular Medicine, University of Cologne, Faculty of Medicine and University Hospital of Cologne, Cologne, Germany
| | - Kálmán Tory
- MTA-SE Lendület Nephrogenetic Laboratory, 1st Department of Pediatrics, Semmelweis University, Budapest, Hungary
| | - Peter F Hoyer
- University Children's Hospital, Clinic for Pediatrics II, University of Duisburg-Essen, Essen, Germany
| | - Bodo B Beck
- Institute of Human Genetics and Center for Molecular Medicine, University of Cologne, Faculty of Medicine and University Hospital of Cologne, Cologne, Germany
| | | | - Hans Blom
- Royal Institute of Technology, Stockholm, Sweden
| | - Bernhard Schermer
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
- CECAD, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany
| | - Thomas Benzing
- Department II of Internal Medicine and Center for Molecular Medicine Cologne, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany.
- CECAD, University of Cologne, Faculty of Medicine and University Hospital Cologne, Cologne, Germany.
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42
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Tahoun M, Chandler JC, Ashton E, Haston S, Hannan A, Kim JS, D’Arco F, Bockenhauer D, Anderson G, Lin MH, Marzouk S, Saied MH, Miner JH, Dattani MT, Waters AM. Mutations in LAMB2 Are Associated With Albuminuria and Optic Nerve Hypoplasia With Hypopituitarism. J Clin Endocrinol Metab 2020; 105:5643661. [PMID: 31769495 PMCID: PMC7048679 DOI: 10.1210/clinem/dgz216] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 11/25/2019] [Indexed: 01/15/2023]
Abstract
CONTEXT Mutations in LAMB2, encoding the basement membrane protein, laminin β2, are associated with an autosomal recessive disorder characterized by congenital nephrotic syndrome, ocular abnormalities, and neurodevelopmental delay (Pierson syndrome). CASE DESCRIPTION This report describes a 12-year-old boy with short stature, visual impairment, and developmental delay who presented with macroscopic hematuria and albuminuria. He had isolated growth hormone deficiency, optic nerve hypoplasia, and a small anterior pituitary with corpus callosum dysgenesis on his cranial magnetic resonance imaging, thereby supporting a diagnosis of optic nerve hypoplasia syndrome. Renal histopathology revealed focal segmental glomerulosclerosis. Using next-generation sequencing on a targeted gene panel for steroid-resistant nephrotic syndrome, compound heterozygous missense mutations were identified in LAMB2 (c.737G>A p.Arg246Gln, c.3982G>C p.Gly1328Arg). Immunohistochemical analysis revealed reduced glomerular laminin β2 expression compared to control kidney and a thin basement membrane on electron microscopy. Laminin β2 is expressed during pituitary development and Lamb2-/- mice exhibit stunted growth, abnormal neural retinae, and here we show, abnormal parenchyma of the anterior pituitary gland. CONCLUSION We propose that patients with genetically undefined optic nerve hypoplasia syndrome should be screened for albuminuria and, if present, screened for mutations in LAMB2.
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Affiliation(s)
- Mona Tahoun
- Clinical and Chemical Pathology Department, Faculty of Medicine, Alexandria University, Egypt
| | - Jennifer C Chandler
- UCL Great Ormond Street Institute of Child Health, University College London, UK
| | - Emma Ashton
- Great Ormond Street Hospital NHS Foundation Trust, London, UK
| | - Scott Haston
- UCL Great Ormond Street Institute of Child Health, University College London, UK
| | - Athia Hannan
- Great Ormond Street Hospital NHS Foundation Trust, London, UK
| | - Ji Soo Kim
- UCL Great Ormond Street Institute of Child Health, University College London, UK
| | - Felipe D’Arco
- Great Ormond Street Hospital NHS Foundation Trust, London, UK
| | - D Bockenhauer
- Great Ormond Street Hospital NHS Foundation Trust, London, UK
| | - G Anderson
- Great Ormond Street Hospital NHS Foundation Trust, London, UK
| | - Meei-Hua Lin
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St Louis, Missouri
| | - Salah Marzouk
- Clinical and Chemical Pathology Department, Faculty of Medicine, Alexandria University, Egypt
| | - Marwa H Saied
- Clinical and Chemical Pathology Department, Faculty of Medicine, Alexandria University, Egypt
| | - Jeffrey H Miner
- Division of Nephrology, Department of Medicine, Washington University School of Medicine, St Louis, Missouri
| | - Mehul T Dattani
- UCL Great Ormond Street Institute of Child Health, University College London, UK
- Great Ormond Street Hospital NHS Foundation Trust, London, UK
| | - Aoife M Waters
- UCL Great Ormond Street Institute of Child Health, University College London, UK
- Great Ormond Street Hospital NHS Foundation Trust, London, UK
- Correspondence: Aoife Waters, MB, BAO, MSc, PhD, FRCPCH, Programme of Developmental Biology of Birth Defects, UCL Great Ormond Street Institute of Child Health, London WC1N 1EH, UK; Consultant Paediatric Nephrologist, Great Ormond Street Hospital NHS Foundation Trust, London, UK. E-mail: ;
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43
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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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44
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Minamikawa S, Miwa S, Inagaki T, Nishiyama K, Kaito H, Ninchoji T, Yamamura T, Nagano C, Sakakibara N, Ishimori S, Hara S, Yoshikawa N, Hirano D, Harada R, Hamada R, Matsunoshita N, Nagata M, Shima Y, Nakanishi K, Nagase H, Takeda H, Morisada N, Iijima K, Nozu K. Molecular mechanisms determining severity in patients with Pierson syndrome. J Hum Genet 2020; 65:355-362. [PMID: 31959872 DOI: 10.1038/s10038-019-0715-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 12/10/2019] [Accepted: 12/11/2019] [Indexed: 01/15/2023]
Abstract
Null variants in LAMB2 cause Pierson syndrome (PS), a severe congenital nephrotic syndrome with ocular and neurological defects. Patients' kidney specimens show complete negativity for laminin β2 expression on glomerular basement membrane (GBM). In contrast, missense variants outside the laminin N-terminal (LN) domain in LAMB2 lead to milder phenotypes. However, we experienced cases not showing these typical genotype-phenotype correlations. In this paper, we report six PS patients: four with mild phenotypes and two with severe phenotypes. We conducted molecular studies including protein expression and transcript analyses. The results revealed that three of the four cases with milder phenotypes had missense variants located outside the LN domain and one of the two severe PS cases had a homozygous missense variant located in the LN domain; these variant positions could explain their phenotypes. However, one mild case possessed a splicing site variant (c.3797 + 5G>A) that should be associated with a severe phenotype. Upon transcript analysis, this variant generated some differently sized transcripts, including completely normal transcript, which could have conferred the milder phenotype. In one severe case, we detected the single-nucleotide substitution of c.4616G>A located outside the LN domain, which should be associated with a milder phenotype. However, we detected aberrant splicing caused by the creation of a novel splice site by this single-base substitution. These are novel mechanisms leading to an atypical genotype-phenotype correlation. In addition, all four cases with milder phenotypes showed laminin β2 expression on GBM. We identified novel mechanisms leading to atypical genotype-phenotype correlation in PS.
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Affiliation(s)
- Shogo Minamikawa
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Saori Miwa
- Department of Pediatrics, Jikei University School of Medicine, Tokyo, Japan
| | - Tetsuji Inagaki
- Department of Pediatric Nephrology, Miyagi Children's Hospital, Sendai, Japan
| | - Kei Nishiyama
- Department of Pediatrics, Graduate School of Medical Science, Kyushu University, Fukuoka, Japan
| | - Hiroshi Kaito
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Takeshi Ninchoji
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Tomohiko Yamamura
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - China Nagano
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Nana Sakakibara
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Shingo Ishimori
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Shigeo Hara
- Department of Diagnostic Pathology, Kobe City Medical Center General Hospital, Kobe, Japan
| | | | - Daishi Hirano
- Department of Pediatrics, Jikei University School of Medicine, Tokyo, Japan
| | - Ryoko Harada
- Department of Nephrology, Tokyo Metropolitan Children's Medical Center, Tokyo, Japan
| | - Riku Hamada
- Department of Nephrology, Tokyo Metropolitan Children's Medical Center, Tokyo, Japan
| | | | - Michio Nagata
- Department of Kidney and Vascular Pathology, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - Yuko Shima
- Department of Pediatrics, Wakayama Medical University, Wakayama, Japan
| | - Koichi Nakanishi
- Department of Child Health and Welfare (Pediatrics), Graduate School of Medicine, University of the Ryukyus, Nishihara, Japan
| | - Hiroaki Nagase
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Hiroki Takeda
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Naoya Morisada
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Kazumoto Iijima
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan
| | - Kandai Nozu
- Department of Pediatrics, Kobe University Graduate School of Medicine, Kobe, Japan.
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45
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Endoplasmic reticulum stress and monogenic kidney diseases in precision nephrology. Pediatr Nephrol 2019; 34:1493-1500. [PMID: 30099615 PMCID: PMC6370526 DOI: 10.1007/s00467-018-4031-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 06/22/2018] [Accepted: 07/20/2018] [Indexed: 01/05/2023]
Abstract
The advent of next-generation sequencing (NGS) in recent years has led to a rapid discovery of novel or rare genetic variants in human kidney cell genes, which is transforming the risk assessment, diagnosis, and treatment of kidney disease. Mutations may lead to protein misfolding, disruption of protein trafficking, and endoplasmic reticulum (ER) retention. An imbalance between the load of misfolded proteins and the folding capacity of the ER causes ER stress and unfolded protein response. Mutations in nephrin (NPHS1), podocin (NPHS2), laminin β2 (LAMB2), and α-actinin-4 (ACTN4) have been shown to induce ER stress in HEK293 cells and podocytes in hereditary nephrotic syndromes; various founder mutations in collagen IV α chains (COL4A) have been demonstrated to activate podocyte ER stress in collagen IV nephropathies; and mutations in uromodulin (UMOD) have been reported to trigger tubular ER stress in autosomal dominant tubulointerstitial kidney disease. Meanwhile, ER resident protein SEC63 may modify disease severity in autosomal dominant polycystic kidney disease. These findings underscore the importance of ER stress in the pathogenesis of monogenic kidney disease. Recently, we have identified mesencephalic astrocyte-derived neurotrophic factor (MANF) and cysteine-rich with EGF-like domains 2 (CRELD2) as urinary ER stress biomarkers in ER stress-mediated kidney diseases.
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Bülow RD, Boor P. Extracellular Matrix in Kidney Fibrosis: More Than Just a Scaffold. J Histochem Cytochem 2019; 67:643-661. [PMID: 31116062 DOI: 10.1369/0022155419849388] [Citation(s) in RCA: 204] [Impact Index Per Article: 40.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Kidney fibrosis is the common histological end-point of progressive, chronic kidney diseases (CKDs) regardless of the underlying etiology. The hallmark of renal fibrosis, similar to all other organs, is pathological deposition of extracellular matrix (ECM). Renal ECM is a complex network of collagens, elastin, and several glycoproteins and proteoglycans forming basal membranes and interstitial space. Several ECM functions beyond providing a scaffold and organ stability are being increasingly recognized, for example, in inflammation. ECM composition is determined by the function of each of the histological compartments of the kidney, that is, glomeruli, tubulo-interstitium, and vessels. Renal ECM is a dynamic structure undergoing remodeling, particularly during fibrosis. From a clinical perspective, ECM proteins are directly involved in several rare renal diseases and indirectly in CKD progression during renal fibrosis. ECM proteins could serve as specific non-invasive biomarkers of fibrosis and scaffolds in regenerative medicine. The gold standard and currently only specific means to measure renal fibrosis is renal biopsy, but new diagnostic approaches are appearing. Here, we discuss the localization, function, and remodeling of major renal ECM components in healthy and diseased, fibrotic kidneys and the potential use of ECM in diagnostics of renal fibrosis and in tissue engineering.
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Affiliation(s)
- Roman David Bülow
- Institute of Pathology, RWTH Aachen University Hospital, Aachen, Germany
| | - Peter Boor
- Institute of Pathology, RWTH Aachen University Hospital, Aachen, Germany.,Department of Nephrology and Immunology, RWTH Aachen University Hospital, Aachen, Germany
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47
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Theocharis AD, Manou D, Karamanos NK. The extracellular matrix as a multitasking player in disease. FEBS J 2019; 286:2830-2869. [PMID: 30908868 DOI: 10.1111/febs.14818] [Citation(s) in RCA: 228] [Impact Index Per Article: 45.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Revised: 02/06/2019] [Accepted: 03/22/2019] [Indexed: 12/12/2022]
Abstract
Extracellular matrices (ECMs) are highly specialized and dynamic three-dimensional (3D) scaffolds into which cells reside in tissues. ECM is composed of a variety of fibrillar components, such as collagens, fibronectin, and elastin, and non-fibrillar molecules as proteoglycans, hyaluronan, and glycoproteins including matricellular proteins. These macromolecular components are interconnected forming complex networks that actively communicate with cells through binding to cell surface receptors and/or matrix effectors. ECMs exert diverse roles, either providing tissues with structural integrity and mechanical properties essential for tissue functions or regulating cell phenotype and functions to maintain tissue homeostasis. ECM molecular composition and structure vary among tissues, and is markedly modified during normal tissue repair as well as during the progression of various diseases. Actually, abnormal ECM remodeling occurring in pathologic circumstances drives disease progression by regulating cell-matrix interactions. The importance of matrix molecules to normal tissue functions is also highlighted by mutations in matrix genes that give rise to genetic disorders with diverse clinical phenotypes. In this review, we present critical and emerging issues related to matrix assembly in tissues and the multitasking roles for ECM in diseases such as osteoarthritis, fibrosis, cancer, and genetic diseases. The mechanisms underlying the various matrix-based diseases are also discussed. Research focused on the highly dynamic 3D ECM networks will help to discover matrix-related causative abnormalities of diseases as well as novel diagnostic tools and therapeutic targets.
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Affiliation(s)
- Achilleas D Theocharis
- Biochemistry, Biochemical Analysis & Matrix Pathobiochemistry Research Group, Laboratory of Biochemistry, Department of Chemistry, University of Patras, Greece
| | - Dimitra Manou
- Biochemistry, Biochemical Analysis & Matrix Pathobiochemistry Research Group, Laboratory of Biochemistry, Department of Chemistry, University of Patras, Greece
| | - Nikos K Karamanos
- Biochemistry, Biochemical Analysis & Matrix Pathobiochemistry Research Group, Laboratory of Biochemistry, Department of Chemistry, University of Patras, Greece
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48
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Sharief SN, Hefni NA, Alzahrani WA, Nazer II, Bayazeed MA, Alhasan KA, Safdar OY, El-Desoky SM, Kari JA. Genetics of congenital and infantile nephrotic syndrome. World J Pediatr 2019; 15:198-203. [PMID: 30721404 DOI: 10.1007/s12519-018-00224-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 12/26/2018] [Indexed: 10/27/2022]
Abstract
BACKGROUND Congenital and infantile nephrotic syndrome (CNS and INS) are rare inherited defects in glomerular filtration involving a variety of gene mutations. This study aimed to analyze all genetic mutations associated with congenital and infantile nephrotic syndrome treated at our institution. We also discussed our different approach secondary to culture and resources. METHODS A retrospective single-center study of all children diagnosed as NS before the age of 1 year over a duration of over one decade. RESULTS Twenty-nine children (12 boys) were included in the study. Their median age (range) was 2.4 (0.1-12) months (20 CNS and 9 INS). Consanguinity was present in 90% of children. The genetic analysis' results were only available for 20 children. An underlying causative homozygous mutation was detected in 18 children (90%): NPHS1 (9), NPHS2(2), LAMB2(3), PLCE1(1), WT1(1), and ITSN1 novel mutation (2). One child had heterozygous mutation of NPHS2 and another child had heterozygous mutation of NPHS1 which could not explain the disease. All CNS cases were all managed with intermittent intravenous albumin infusion, ACEi, diuretics, and indomethacin. None of the children were managed by nephrectomy followed by peritoneal dialysis (PD) because of limited resources. Only one child achieved partial remission, while 15 children died at a median (range) age of 5.8 (1.25-29) months. The remaining 14 children were followed up for an average of 36 (3.9-120) months. Three children progressed to end-stage kidney disease and PD was performed in only two children. CONCLUSIONS NPHS1 is the main underlying cause of CNS and INS in our study population. CNS and INS were associated with high morbidity and mortality.
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Affiliation(s)
| | | | | | | | | | - Khalid A Alhasan
- College of Medicine, Pediatric Department, King Saud University, Riyadh, Kingdom of Saudi Arabia
| | - Osama Y Safdar
- King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia.,Department of Pediatrics, Faculty of Medicine, Pediatric Nephrology Center of Excellence, King Abdulaziz University, PO Box 80215, Jeddah, 21589, Kingdom of Saudi Arabia
| | - Sherif M El-Desoky
- King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia.,Department of Pediatrics, Faculty of Medicine, Pediatric Nephrology Center of Excellence, King Abdulaziz University, PO Box 80215, Jeddah, 21589, Kingdom of Saudi Arabia
| | - Jameela Abdulaziz Kari
- King Abdulaziz University, Jeddah, Kingdom of Saudi Arabia. .,Department of Pediatrics, Faculty of Medicine, Pediatric Nephrology Center of Excellence, King Abdulaziz University, PO Box 80215, Jeddah, 21589, Kingdom of Saudi Arabia.
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49
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Nicolau S, Milone M. The Electrophysiology of Presynaptic Congenital Myasthenic Syndromes With and Without Facilitation: From Electrodiagnostic Findings to Molecular Mechanisms. Front Neurol 2019; 10:257. [PMID: 30941097 PMCID: PMC6433874 DOI: 10.3389/fneur.2019.00257] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Accepted: 02/26/2019] [Indexed: 11/13/2022] Open
Abstract
Congenital myasthenic syndromes (CMS) are a group of inherited disorders of neuromuscular transmission most commonly presenting with early onset fatigable weakness, ptosis, and ophthalmoparesis. CMS are classified according to the localization of the causative molecular defect. CMS with presynaptic dysfunction can be caused by mutations in several different genes, including those involved in acetylcholine synthesis, its packaging into synaptic vesicles, vesicle docking, and release from the presynaptic nerve terminal and neuromuscular junction development and maintenance. Electrodiagnostic testing is key in distinguishing CMS from other neuromuscular disorders with similar clinical features as well as for revealing features pointing to a specific molecular diagnosis. A decremental response on low-frequency repetitive nerve stimulation (RNS) is present in most presynaptic CMS. In CMS with deficits in acetylcholine resynthesis however, a decrement may only appear after conditioning with exercise or high-frequency RNS and characteristically displays a slow recovery. Facilitation occurs in CMS caused by mutations in VAMP1, UNC13A, SYT2, AGRN, LAMA5. By contrast, facilitation is absent in the other presynaptic CMS described to date. An understanding of the underlying molecular mechanisms therefore assists the interpretation of electrodiagnostic findings in patients with suspected CMS.
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Affiliation(s)
- Stefan Nicolau
- Department of Neurology, Mayo Clinic, Rochester, MN, United States
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50
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Heikkinen A, Härönen H, Norman O, Pihlajaniemi T. Collagen XIII and Other ECM Components in the Assembly and Disease of the Neuromuscular Junction. Anat Rec (Hoboken) 2019; 303:1653-1663. [PMID: 30768864 DOI: 10.1002/ar.24092] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Revised: 08/17/2018] [Accepted: 09/27/2018] [Indexed: 12/15/2022]
Abstract
Alongside playing structural roles, the extracellular matrix (ECM) acts as an interaction platform for cellular homeostasis, organ development, and maintenance. The necessity of the ECM is highlighted by the diverse, sometimes very serious diseases that stem from defects in its components. The neuromuscular junction (NMJ) is a large peripheral motor synapse differing from its central counterparts through the ECM included at the synaptic cleft. Such synaptic basal lamina (BL) is specialized to support NMJ establishment, differentiation, maturation, stabilization, and function and diverges in molecular composition from the extrasynaptic ECM. Mutations, toxins, and autoantibodies may compromise NMJ integrity and function, thereby leading to congenital myasthenic syndromes (CMSs), poisoning, and autoimmune diseases, respectively, and all these conditions may involve synaptic ECM molecules. With neurotransmission degraded or blocked, muscle function is impaired or even prevented. At worst, this can be fatal. The article reviews the synaptic BL composition required for assembly and function of the NMJ molecular machinery through the lens of studies primarily with mouse models but also with human patients. In-depth focus is given to collagen XIII, a postsynaptic-membrane-spanning but also shed ECM protein that in recent years has been revealed to be a significant component for the NMJ. Its deficiency in humans causes CMS, and autoantibodies against it have been recognized in autoimmune myasthenia gravis. Mouse models have exposed numerous details that appear to recapitulate human NMJ phenotypes relatively faithfully and thereby can be readily used to generate information necessary for understanding and ultimately treating human diseases. Anat Rec, 2019. © 2019 Wiley Periodicals, Inc.
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Affiliation(s)
- Anne Heikkinen
- Oulu Center for Cell-Matrix Research, Biocenter Oulu, Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Heli Härönen
- Oulu Center for Cell-Matrix Research, Biocenter Oulu, Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Oula Norman
- Oulu Center for Cell-Matrix Research, Biocenter Oulu, Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
| | - Taina Pihlajaniemi
- Oulu Center for Cell-Matrix Research, Biocenter Oulu, Faculty of Biochemistry and Molecular Medicine, University of Oulu, Oulu, Finland
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