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Meyer S, Kaulfuß S, Zechel S, Kummer K, Seif Amir Hosseini A, Ernst MS, Schmidt J, Pauli S, Zschüntzsch J. Evidence of Two Novel LAMA2 Variants in a Patient With Muscular Dystrophy: Facing the Challenges of a Certain Diagnosis. Front Neurol 2022; 13:893605. [PMID: 35928135 PMCID: PMC9344914 DOI: 10.3389/fneur.2022.893605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 06/13/2022] [Indexed: 11/13/2022] Open
Abstract
BackgroundBenefits and challenges resulting from advances in genetic diagnostics are two sides of the same coin. Facilitation of a correct and timely diagnosis is paralleled by challenges in interpretation of variants of unknown significance (VUS). Focusing on an individual VUS-re-classification pipeline, this study offers a diagnostic approach for clinically suspected hereditary muscular dystrophy by combining the expertise of an interdisciplinary team.MethodsIn a multi-step approach, a thorough phenotype assessment including clinical examination, laboratory work, muscle MRI and histopathological evaluation of muscle was performed in combination with advanced Next Generation Sequencing (NGS). Different in-silico tools and prediction programs like Alamut, SIFT, Polyphen, MutationTaster and M-Cap as well as 3D- modeling of protein structure and RNA-sequencing were employed to determine clinical significance of the LAMA2 variants.ResultsTwo previously unknown sequence alterations in LAMA2 were detected, a missense variant was classified initially according to ACMG guidelines as a VUS (class 3) whereas a second splice site variant was deemed as likely pathogenic (class 4). Pathogenicity of the splice site variant was confirmed by mRNA sequencing and nonsense mediated decay (NMD) was detected. Combination of the detected variants could be associated to the LGMDR23-phenotype based on the MRI matching and literature research.DiscussionTwo novel variants in LAMA2 associated with LGMDR23-phenotype are described. This study illustrates challenges of the genetic findings due to their VUS classification and elucidates how individualized diagnostic procedure has contributed to the accurate diagnosis in the spectrum of LGMD.
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Affiliation(s)
- Stefanie Meyer
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Silke Kaulfuß
- Department of Human Genetics, University Medical Center Göttingen, Göttingen, Germany
| | - Sabrina Zechel
- Department of Neuropathology, University Medical Center Göttingen, Göttingen, Germany
| | - Karsten Kummer
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Ali Seif Amir Hosseini
- Department of Diagnostic and Interventional Radiology, University Medical Center Göttingen, Göttingen, Germany
| | - Marielle Sophie Ernst
- Department of Neuroradiology, University Medical Center Göttingen, Göttingen, Germany
| | - Jens Schmidt
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
- Department of Neurology and Pain Treatment, Immanuel Klinik Rüdersdorf, University Hospital of the Brandenburg Medical School Theodor Fontane, Rüdersdorf bei Berlin, Germany
- Faculty of Health Sciences Brandenburg, Brandenburg Medical School Theodor Fontane, Rüdersdorf bei Berlin, Germany
| | - Silke Pauli
- Department of Human Genetics, University Medical Center Göttingen, Göttingen, Germany
| | - Jana Zschüntzsch
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
- *Correspondence: Jana Zschüntzsch
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Benítez R, Núñez Y, Ayuso M, Isabel B, Fernández-Barroso MA, De Mercado E, Gómez-Izquierdo E, García-Casco JM, López-Bote C, Óvilo C. Changes in Biceps femoris Transcriptome along Growth in Iberian Pigs Fed Different Energy Sources and Comparative Analysis with Duroc Breed. Animals (Basel) 2021; 11:ani11123505. [PMID: 34944282 PMCID: PMC8697974 DOI: 10.3390/ani11123505] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 11/26/2021] [Accepted: 12/06/2021] [Indexed: 12/19/2022] Open
Abstract
Simple Summary The genetic mechanisms that regulate biological processes, such as skeletal muscle development and growth, or intramuscular fat deposition, have attracted great interest, given their impact on production traits and meat quality. In this sense, a comparison of the transcriptome of skeletal muscle between phenotypically different pig breeds, or along growth, could be useful to improve the understanding of the molecular processes underlying the differences in muscle metabolism and phenotypic traits, potentially driving the identification of causal genes, regulators and metabolic pathways involved in their variability. Abstract This experiment was conducted to investigate the effects of developmental stage, breed, and diet energy source on the genome-wide expression, meat quality traits, and tissue composition of biceps femoris muscle in growing pure Iberian and Duroc pigs. The study comprised 59 Iberian (IB) and 19 Duroc (DU) animals, who started the treatment at an average live weight (LW) of 19.9 kg. The animals were kept under identical management conditions and fed two diets with different energy sources (6% high oleic sunflower oil or carbohydrates). Twenty-nine IB animals were slaughtered after seven days of treatment at an average LW of 24.1 kg, and 30 IB animals plus all the DU animals were slaughtered after 47 days at an average LW of 50.7 kg. The main factors affecting the muscle transcriptome were age, with 1832 differentially expressed genes (DEGs), and breed (1055 DEGs), while the effect of diet on the transcriptome was very small. The results indicated transcriptome changes along time in Iberian animals, being especially related to growth and tissue development, extracellular matrix (ECM) composition, and cytoskeleton organization, with DEGs affecting relevant functions and biological pathways, such as myogenesis. The breed also affected functions related to muscle development and cytoskeleton organization, as well as functions related to solute transport and lipid and carbohydrate metabolism. Taking into account the results of the two main comparisons (age and breed effects), we can postulate that the Iberian breed is more precocious than the Duroc breed, regarding myogenesis and muscle development, in the studied growing stage.
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Affiliation(s)
- Rita Benítez
- Departamento de Mejora Genética Animal, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CSIC), 28040 Madrid, Spain; (R.B.); (Y.N.); (M.A.F.-B.); (J.M.G.-C.)
| | - Yolanda Núñez
- Departamento de Mejora Genética Animal, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CSIC), 28040 Madrid, Spain; (R.B.); (Y.N.); (M.A.F.-B.); (J.M.G.-C.)
| | - Miriam Ayuso
- Department of Veterinary Sciences, Faculty of Biomedical, Pharmaceutical and Veterinary Sciences, University of Antwerp, B-2610 Wilrijk, Belgium;
| | - Beatriz Isabel
- Departamento de Producción Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, 28040 Madrid, Spain; (B.I.); (C.L.-B.)
| | - Miguel A. Fernández-Barroso
- Departamento de Mejora Genética Animal, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CSIC), 28040 Madrid, Spain; (R.B.); (Y.N.); (M.A.F.-B.); (J.M.G.-C.)
| | - Eduardo De Mercado
- Centro de Pruebas de Porcino ITACYL, Hontalbilla, 40353 Segovia, Spain; (E.D.M.); (E.G.-I.)
| | - Emilio Gómez-Izquierdo
- Centro de Pruebas de Porcino ITACYL, Hontalbilla, 40353 Segovia, Spain; (E.D.M.); (E.G.-I.)
| | - Juan M. García-Casco
- Departamento de Mejora Genética Animal, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CSIC), 28040 Madrid, Spain; (R.B.); (Y.N.); (M.A.F.-B.); (J.M.G.-C.)
| | - Clemente López-Bote
- Departamento de Producción Animal, Facultad de Veterinaria, Universidad Complutense de Madrid, 28040 Madrid, Spain; (B.I.); (C.L.-B.)
| | - Cristina Óvilo
- Departamento de Mejora Genética Animal, Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA-CSIC), 28040 Madrid, Spain; (R.B.); (Y.N.); (M.A.F.-B.); (J.M.G.-C.)
- Correspondence: ; Tel.: +34-91-3471492
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Packer D, Martin PT. Micro-laminin gene therapy can function as an inhibitor of muscle disease in the dy W mouse model of MDC1A. Mol Ther Methods Clin Dev 2021; 21:274-287. [PMID: 33869655 PMCID: PMC8026908 DOI: 10.1016/j.omtm.2021.02.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Accepted: 02/03/2021] [Indexed: 02/04/2023]
Abstract
Gene replacement for laminin-α2-deficient congenital muscular dystrophy 1A (MDC1A) is currently not possible using a single adeno-associated virus (AAV) vector due to the large size of the LAMA2 gene. LAMA2 encodes laminin-α2, a subunit of the trimeric laminin-211 extracellular matrix (ECM) protein that is the predominant laminin expressed in skeletal muscle. LAMA2 expression stabilizes skeletal muscle, in part by binding membrane receptors via its five globular (G) domains. We created a small, AAV-deliverable, micro-laminin gene therapy that expresses these G1-5 domains, LAMA2(G1-5), to test their therapeutic efficacy in the dyW mouse model for MDC1A. We also fused the heparin-binding (HB) domain from HB epidermal growth factor-like growth factor (HB-EGF) to LAMA2(G1-5) to test whether this would increase muscle ECM expression. dyW mice treated intravenously with rAAV9.CMV.HB-LAMA2(G1-5) showed increased muscle ECM expression of transgenic protein relative to mice treated with rAAV9.CMV.LAMA2(G1-5) and showed improved weight-normalized forelimb grip strength relative to untreated dyW mice. Additionally, dyW muscle fibers expressing either micro-laminin protein showed some measures of reduced pathology, although levels of muscle cell apoptosis and inflammation were not decreased. Although systemic expression of rAAV9.CMV.HB-LAMA2(G1-5) did not inhibit all disease phenotypes, these studies demonstrate the feasibility of using a micro-laminin gene therapy strategy to deliver gene replacement for MDC1A.
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Affiliation(s)
- Davin Packer
- Neuroscience Graduate Program, The Ohio State University, Columbus, OH, USA
- Center for Gene Therapy, Abigail Wexner Research Institute, The Research Institute at Nationwide Children’s Hospital, Columbus, OH, USA
| | - Paul T. Martin
- Center for Gene Therapy, Abigail Wexner Research Institute, The Research Institute at Nationwide Children’s Hospital, Columbus, OH, USA
- Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, USA
- Corresponding author Paul T. Martin, Center for Gene Therapy, Abigail Wexner Research Institute, The Research Institute at Nationwide Children’s Hospital, 700 Children’s Drive, Columbus, OH 43209, USA.
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Arreguin AJ, Colognato H. Brain Dysfunction in LAMA2-Related Congenital Muscular Dystrophy: Lessons From Human Case Reports and Mouse Models. Front Mol Neurosci 2020; 13:118. [PMID: 32792907 PMCID: PMC7390928 DOI: 10.3389/fnmol.2020.00118] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 06/09/2020] [Indexed: 12/26/2022] Open
Abstract
Laminin α2 gene (LAMA2)-related Congenital Muscular Dystrophy (CMD) was distinguished by a defining central nervous system (CNS) abnormality—aberrant white matter signals by MRI—when first described in the 1990s. In the past 25 years, researchers and clinicians have expanded our knowledge of brain involvement in LAMA2-related CMD, also known as Congenital Muscular Dystrophy Type 1A (MDC1A). Neurological changes in MDC1A can be structural, including lissencephaly and agyria, as well as functional, including epilepsy and intellectual disability. Mouse models of MDC1A include both spontaneous and targeted LAMA2 mutations and range from a partial loss of LAMA2 function (e.g., dy2J/dy2J), to a complete loss of LAMA2 expression (dy3K/dy3K). Diverse cellular and molecular changes have been reported in the brains of MDC1A mouse models, including blood-brain barrier dysfunction, altered neuro- and gliogenesis, changes in synaptic plasticity, and decreased myelination, providing mechanistic insight into potential neurological dysfunction in MDC1A. In this review article, we discuss selected studies that illustrate the potential scope and complexity of disturbances in brain development in MDC1A, and as well as highlight mechanistic insights that are emerging from mouse models.
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Affiliation(s)
- Andrea J Arreguin
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY, United States.,Medical Scientist Training Program (MSTP), Stony Brook University, Stony Brook, NY, United States
| | - Holly Colognato
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY, United States
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Nguyen Q, Lim KRQ, Yokota T. Current understanding and treatment of cardiac and skeletal muscle pathology in laminin-α2 chain-deficient congenital muscular dystrophy. APPLICATION OF CLINICAL GENETICS 2019; 12:113-130. [PMID: 31308722 PMCID: PMC6618038 DOI: 10.2147/tacg.s187481] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Accepted: 05/08/2019] [Indexed: 01/04/2023]
Abstract
Congenital muscular dystrophy (CMD) is a class of severe early-onset muscular dystrophies affecting skeletal/cardiac muscles as well as the central nervous system (CNS). Laminin-α2 chain-deficient congenital muscular dystrophy (LAMA2 MD), also known as merosin-deficient congenital muscular dystrophy type 1A (MDC1A), is an autosomal recessive CMD characterized by severe muscle weakness and degeneration apparent at birth or in the first 6 months of life. LAMA2 MD is the most common congenital muscular dystrophy, affecting approximately 4 in 500,000 children. The most common cause of death in early-onset LAMA2 MD is respiratory tract infection, with 30% of them dying within the first decade of life. LAMA2 MD is caused by loss-of-function mutations in the LAMA2 gene encoding for the laminin-α2 chain, one of the subunits of laminin-211. Laminin-211 is an extracellular matrix protein that functions to stabilize the basement membrane and muscle fibers during contraction. Since laminin-α2 is expressed in many tissue types including skeletal muscle, cardiac muscle, Schwann cells, and trophoblasts, patients with LAMA2 MD experience a multi-systemic clinical presentation depending on the extent of laminin-α2 chain deficiency. Cardiac manifestations are typically associated with a complete absence of laminin-α2; however, recent case reports highlight cardiac involvement in partial laminin-α2 chain deficiency. Laminin-211 is also expressed in the brain, and many patients have abnormalities on brain imaging; however, mental retardation and/or seizures are rarely seen. Currently, there is no cure for LAMA2 MD, but various therapies are being investigated in an effort to lessen the severity of LAMA2 MD. For example, antisense oligonucleotide-mediated exon skipping and CRISPR-Cas9 genome editing have efficiently restored the laminin-α2 chain in mouse models in vivo. This review consolidates information on the clinical presentation, genetic basis, pathology, and current treatment approaches for LAMA2 MD.
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Affiliation(s)
- Quynh Nguyen
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Kenji Rowel Q Lim
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Toshifumi Yokota
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada.,The Friends of Garrett Cumming Research & Muscular Dystrophy Canada, HM Toupin Neurological Science Research Chair, Edmonton, AB, Canada
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Nirwane A, Yao Y. Laminins and their receptors in the CNS. Biol Rev Camb Philos Soc 2019; 94:283-306. [PMID: 30073746 DOI: 10.1111/brv.12454] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 07/05/2018] [Accepted: 07/09/2018] [Indexed: 01/24/2023]
Abstract
Laminin, an extracellular matrix protein, is widely expressed in the central nervous system (CNS). By interacting with integrin and non-integrin receptors, laminin exerts a large variety of important functions in the CNS in both physiological and pathological conditions. Due to the existence of many laminin isoforms and their differential expression in various cell types in the CNS, the exact functions of each individual laminin molecule in CNS development and homeostasis remain largely unclear. In this review, we first briefly introduce the structure and biochemistry of laminins and their receptors. Next, the dynamic expression of laminins and their receptors in the CNS during both development and in adulthood is summarized in a cell-type-specific manner, which allows appreciation of their functional redundancy/compensation. Furthermore, we discuss the biological functions of laminins and their receptors in CNS development, blood-brain barrier (BBB) maintenance, neurodegeneration, stroke, and neuroinflammation. Last, key challenges and potential future research directions are summarized and discussed. Our goals are to provide a synthetic review to stimulate future studies and promote the formation of new ideas/hypotheses and new lines of research in this field.
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Affiliation(s)
- Abhijit Nirwane
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, 240 W Green Street, Athens, GA 30602, U.S.A
| | - Yao Yao
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, 240 W Green Street, Athens, GA 30602, U.S.A
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Geissler SA, Sabin AL, Besser RR, Gooden OM, Shirk BD, Nguyen QM, Khaing ZZ, Schmidt CE. Biomimetic hydrogels direct spinal progenitor cell differentiation and promote functional recovery after spinal cord injury. J Neural Eng 2018; 15:025004. [PMID: 29303112 PMCID: PMC5988207 DOI: 10.1088/1741-2552/aaa55c] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVE Demyelination that results from disease or traumatic injury, such as spinal cord injury (SCI), can have a devastating effect on neural function and recovery. Many researchers are examining treatments to minimize demyelination by improving oligodendrocyte availability in vivo. Transplantation of stem and oligodendrocyte progenitor cells is a promising option, however, trials are plagued by undirected differentiation. Here we introduce a biomaterial that has been optimized to direct the differentiation of neural progenitor cells (NPCs) toward oligodendrocytes as a cell delivery vehicle after SCI. APPROACH A collagen-based hydrogel was modified to mimic the mechanical properties of the neonatal spinal cord, and components present in the developing extracellular matrix were included to provide appropriate chemical cues to the NPCs to direct their differentiation toward oligodendrocytes. The hydrogel with cells was then transplanted into a unilateral cervical contusion model of SCI to examine the functional recovery with this treatment. Six behavioral tests and histological assessment were performed to examine the in vivo response to this treatment. MAIN RESULTS Our results demonstrate that we can achieve a significant increase in oligodendrocyte differentiation of NPCs compared to standard culture conditions using a three-component biomaterial composed of collagen, hyaluronic acid, and laminin that has mechanical properties matched to those of neonatal neural tissue. Additionally, SCI rats with hydrogel transplants, with and without NPCs, showed functional recovery. Animals transplanted with hydrogels with NPCs showed significantly increased functional recovery over six weeks compared to the media control group. SIGNIFICANCE The three-component hydrogel presented here has the potential to provide cues to direct differentiation in vivo to encourage regeneration of the central nervous system.
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Affiliation(s)
- Sydney A Geissler
- Department of Biomedical Engineering, University of Texas at Austin, Austin, TX, United States of America. J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, FL, United States of America
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Rogers RS, Nishimune H. The role of laminins in the organization and function of neuromuscular junctions. Matrix Biol 2016; 57-58:86-105. [PMID: 27614294 DOI: 10.1016/j.matbio.2016.08.008] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Revised: 08/10/2016] [Accepted: 08/17/2016] [Indexed: 01/11/2023]
Abstract
The synapse between motor neurons and skeletal muscle is known as the neuromuscular junction (NMJ). Proper alignment of presynaptic and post-synaptic structures of motor neurons and muscle fibers, respectively, is essential for efficient motor control of skeletal muscles. The synaptic cleft between these two cells is filled with basal lamina. Laminins are heterotrimer extracellular matrix molecules that are key members of the basal lamina. Laminin α4, α5, and β2 chains specifically localize to NMJs, and these laminin isoforms play a critical role in maintenance of NMJs and organization of synaptic vesicle release sites known as active zones. These individual laminin chains exert their role in organizing NMJs by binding to their receptors including integrins, dystroglycan, and voltage-gated calcium channels (VGCCs). Disruption of these laminins or the laminin-receptor interaction occurs in neuromuscular diseases including Pierson syndrome and Lambert-Eaton myasthenic syndrome (LEMS). Interventions to maintain proper level of laminins and their receptor interactions may be insightful in treating neuromuscular diseases and aging related degeneration of NMJs.
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Affiliation(s)
- Robert S Rogers
- Department of Anatomy and Cell Biology, University of Kansas School of Medicine, Kansas City, Kansas, USA.
| | - Hiroshi Nishimune
- Department of Anatomy and Cell Biology, University of Kansas School of Medicine, Kansas City, Kansas, USA.
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Määttä M, Virtanen I, Burgeson R, Autio-Harmainen H. Comparative Analysis of the Distribution of Laminin Chains in the Basement Membranes in Some Malignant Epithelial Tumors: The α1 Chain of Laminin Shows a Selected Expression Pattern in Human Carcinomas. J Histochem Cytochem 2016; 49:711-26. [PMID: 11373318 DOI: 10.1177/002215540104900605] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Laminins (Ln), together with Type IV collagen and nidogen-1, form the structural integrity of the basement membranes (BM). In this study we used immunohistochemistry to show the distribution of laminin chains α1, α3, α5, β1, β2, β3, γ1, γ2, as well as Type IV collagen, in various types of carcinomas and in normal tissues. Except for diffuse gastric carcinomas and infiltrative breast carcinomas, the malignant epithelial tumor clusters were surrounded by quite a continuous BM in most tumors. These BMs comprised most abundantly Ln α5, β1, and γ1 chains. Conversely, the Ln α1 chain, a component of laminins-1 and -3, showed the most restricted distribution in BMs of both normal tissues and malignancies, being moderately present in carcinomas of thyroid gland and ovary and in intraductal carcinomas of breast. In other types of carcinomas, immunoreactivity for Ln α1 chain was found more randomly and was practically negative in carcinomas of tongue, stomach, and colon. These findings were comparable to those observed by in situ hybridization, which showed that carcinomas of thyroid gland and intraductal carcinomas of breast constitutively expressed Ln α1 mRNA and that the epithelial tumor cells were the main producers of it. The results suggest that epithelial malignancies, except for infiltrative breast and diffuse gastric carcinomas, produce more notable amounts of BM macromolecules in their growth substratum than has previously been anticipated. Corroborating their widespread distribution in normal epithelial tissues, the chains of Lns-5 and -10 are the most abundant Ln molecules in the corresponding carcinomas.
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Affiliation(s)
- M Määttä
- Department of Pathology, University of Oulu, Oulu, Finland
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Yeo IS, Min SK, Kang HK, Kwon TK, Jung SY, Min BM. Identification of a bioactive core sequence from human laminin and its applicability to tissue engineering. Biomaterials 2015; 73:96-109. [PMID: 26406450 DOI: 10.1016/j.biomaterials.2015.09.004] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2015] [Revised: 08/28/2015] [Accepted: 09/09/2015] [Indexed: 12/30/2022]
Abstract
Finding bioactive short peptides derived from proteins is a critical step to the advancement of tissue engineering and regenerative medicine, because the former maintains the functions of the latter without immunogenicity in biological systems. Here, we discovered a bioactive core nonapeptide sequence, PPFEGCIWN (residues 2678-2686; Ln2-LG3-P2-DN3), from the human laminin α2 chain, and investigated the role of this peptide in binding to transmembrane proteins to promote intracellular events leading to cell functions. This minimum bioactive sequence had neither secondary nor tertiary structures in a computational structure prediction. Nonetheless, Ln2-LG3-P2-DN3 bound to various cell types as actively as laminin in cell adhesion assays. The in vivo healing tests using rats revealed that Ln2-LG3-P2-DN3 promoted bone formation without any recognizable antigenic activity. Ln2-LG3-P2-DN3-treated titanium (Ti) discs and Ti implant surfaces caused the enhancement of bone cell functions in vitro and induced faster osseointegration in vivo, respectively. These findings established a minimum bioactive sequence within human laminin, and its potential application value for regenerative medicine, especially for bone tissue engineering.
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Affiliation(s)
- In-Sung Yeo
- Department of Prosthodontics, Seoul National University School of Dentistry, 101 Daehak-Ro, Jongno-Gu, Seoul 110-744, Republic of Korea.
| | - Seung-Ki Min
- Department of Oral and Maxillofacial Surgery, Seoul National University School of Dentistry, 101 Daehak-Ro, Jongno-Gu, Seoul 110-744, Republic of Korea.
| | - Hyun Ki Kang
- Department of Oral Biochemistry and Program in Cancer and Developmental Biology and Dental Research Institute, Seoul National University School of Dentistry, 101 Daehak-Ro, Jongno-Gu, Seoul 110-744, Republic of Korea.
| | - Taek-Ka Kwon
- Department of Dentistry, St. Vincent Hospital, Catholic University of Korea, Ji-Dong, Paldal-Ku, Suwon 442-723, Republic of Korea.
| | - Sung Youn Jung
- Department of Oral Biochemistry and Program in Cancer and Developmental Biology and Dental Research Institute, Seoul National University School of Dentistry, 101 Daehak-Ro, Jongno-Gu, Seoul 110-744, Republic of Korea.
| | - Byung-Moo Min
- Department of Oral Biochemistry and Program in Cancer and Developmental Biology and Dental Research Institute, Seoul National University School of Dentistry, 101 Daehak-Ro, Jongno-Gu, Seoul 110-744, Republic of Korea.
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Durbeej M. Laminin-α2 Chain-Deficient Congenital Muscular Dystrophy: Pathophysiology and Development of Treatment. CURRENT TOPICS IN MEMBRANES 2015; 76:31-60. [PMID: 26610911 DOI: 10.1016/bs.ctm.2015.05.002] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Laminin-211 is a major constituent of the skeletal muscle basement membrane. It stabilizes skeletal muscle and influences signal transduction events from the myomatrix to the muscle cell. Mutations in the gene encoding the α2 chain of laminin-211 lead to congenital muscular dystrophy type 1A (MDC1A), a life-threatening disease characterized by severe hypotonia, progressive muscle weakness, and joint contractures. Common complications include severely impaired motor ability, respiratory failure, and feeding difficulties. Several adequate animal models for laminin-α2 chain deficiency exist and analyses of different MDC1A mouse models have led to a significant improvement in our understanding of MDC1A pathogenesis. Importantly, the animal models have been indispensable tools for the preclinical development of new therapeutic approaches for laminin-α2 chain deficiency, highlighting a number of important disease driving mechanisms that can be targeted by pharmacological approaches. In this chapter, I will describe laminin-211 and discuss the cellular and molecular pathophysiology of MDC1A as well as progression toward development of treatment.
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Affiliation(s)
- Madeleine Durbeej
- Department of Experimental Medical Science, Lund University, Lund, Sweden.
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Titanium surface coating with a laminin-derived functional peptide promotes bone cell adhesion. BIOMED RESEARCH INTERNATIONAL 2013; 2013:638348. [PMID: 23586052 PMCID: PMC3622367 DOI: 10.1155/2013/638348] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Revised: 03/04/2013] [Accepted: 03/04/2013] [Indexed: 11/18/2022]
Abstract
Laminin-derived peptide coatings can enhance epithelial cell adhesion to implants, and the positive effect of these peptides on bone cell adhesion has been anticipated. The purpose of this study was to evaluate the improvement in bone cell attachment to and activity on titanium (Ti) scaffolds coated with a laminin-derived functional peptide, Ln2-P3 (the DLTIDDSYWYRI motif). Four Ti disc surfaces were prepared, and a human osteosarcoma (HOS) cell attachment test was performed to select two candidate surfaces for peptide coating. These two candidates were then coated with Ln2-P3 peptide, a scrambled peptide, or left uncoated to measure cell attachment to each surface, following which one surface was chosen to assess alkaline phosphatase (ALP) activity and osteogenic marker gene expression with quantitative real-time PCR. On the commercially pure Ti surface, the Ln2-P3 coating significantly increased cellular ALP activity and the expression levels of ALP and bone sialoprotein mRNA as compared with the scrambled peptide-coated and uncoated surfaces. In conclusion, although further in vivo studies are needed, the findings of this in vitro study indicate that the Ln2-P3-coated implant surface promotes bone cell adhesion, which has clinical implications for reducing the overall treatment time of dental implant therapy.
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Kang HK, Kim OB, Min SK, Jung SY, Jang DH, Kwon TK, Min BM, Yeo IS. The effect of the DLTIDDSYWYRI motif of the human laminin α2 chain on implant osseointegration. Biomaterials 2013; 34:4027-4037. [PMID: 23465831 DOI: 10.1016/j.biomaterials.2013.02.023] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2012] [Accepted: 02/11/2013] [Indexed: 10/27/2022]
Abstract
Considerable effort has been directed towards replacing lost teeth using tissue-engineering methods such as titanium implants. A number of studies have tried to modify bioinert titanium surfaces by coating them with functionally bioactive molecules for faster and stronger osseointegration than pure titanium surfaces. Recently, peptides have been recognized as valuable scientific tools in the field of tissue-engineering. The DLTIDDSYWYRI motif of the human laminin-2 α2 chain has been previously reported to promote the attachment of various cell types; however, the in vivo effects of the DLTIDDSYWYRI motif on new bone formation have not yet been studied. To examine whether a laminin-2-derived peptide can promote osseointegration by accelerating new bone formation in vivo, we applied titanium implants coated with the DLTIDDSYWYRI motif in a rabbit tibia model. The application of the DLTIDDSYWYRI motif-treated implant to tibia wounds enhanced collagen deposition and alkaline phosphatase expression. It significantly promoted implant osseointegration compared with treatment with scrambled peptide-treated implants by increasing the bone-to-implant contact ratio and bone area. These findings support the hypothesis that the DLTIDDSYWYRI motif acts as an effective osseointegration accelerator by enhancing new bone formation.
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Affiliation(s)
- Hyun Ki Kang
- Department of Oral Biochemistry and Program in Cancer and Developmental Biology, Dental Research Institute, Seoul National University School of Dentistry, 28 Yeonkun-Dong, Chongno-Ku, Seoul 110-749, Republic of Korea.
| | - O Bok Kim
- Department of Oral Biochemistry and Program in Cancer and Developmental Biology, Dental Research Institute, Seoul National University School of Dentistry, 28 Yeonkun-Dong, Chongno-Ku, Seoul 110-749, Republic of Korea.
| | - Seung-Ki Min
- Department of Oral and Maxillofacial Surgery, Seoul National University School of Dentistry, 28 Yeonkun-Dong, Chongno-Ku, Seoul 110-749, Republic of Korea.
| | - Sung Youn Jung
- Department of Oral Biochemistry and Program in Cancer and Developmental Biology, Dental Research Institute, Seoul National University School of Dentistry, 28 Yeonkun-Dong, Chongno-Ku, Seoul 110-749, Republic of Korea.
| | - Da Hyun Jang
- Department of Oral Biochemistry and Program in Cancer and Developmental Biology, Dental Research Institute, Seoul National University School of Dentistry, 28 Yeonkun-Dong, Chongno-Ku, Seoul 110-749, Republic of Korea.
| | - Taek-Ka Kwon
- Department of Dentistry, St. Vincent Hospital, Catholic University of Korea, Ji-Dong, Paldal-Ku, Suwon 442-723, Republic of Korea.
| | - Byung-Moo Min
- Department of Oral Biochemistry and Program in Cancer and Developmental Biology, Dental Research Institute, Seoul National University School of Dentistry, 28 Yeonkun-Dong, Chongno-Ku, Seoul 110-749, Republic of Korea.
| | - In-Sung Yeo
- Department of Prosthodontics and Dental Research Institute, Seoul National University School of Dentistry, 28 Yeonkun-Dong, Chongno-Ku, Seoul 110-749, Republic of Korea.
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Kumagai C, Kitagawa Y. Potential molecular chaperones involved in laminin chain assembly. Cytotechnology 2012; 25:173-82. [PMID: 22358889 DOI: 10.1023/a:1007920018109] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
To explore potential molecular chaperones involved in the intracellular assembly of laminin chains, bovine aortic endothelial cells were treated with a thiol cleavable divalent cross-linking reagent, dithio-bis-(succinimidylpropionate), and cellular proteins cross-linked to laminin chains were co-immunoprecipitated with anti-laminin antiserum. Sodium dodecylsulfate (SDS) gel electrophoresis of the precipitate under reducing condition showed polypeptides with estimated sizes of 80, 60 and 50 kDa together with laminin chains. Two dimensional electrophoresis, in which non-reducing and reducing SDS electrophoresis were combined, suggested that many molecules of these polypeptides were cross-linked to each laminin chain. Sepharose CL-4B beads conjugated with E8 fragment of mouse laminin-1 was prepared. Affinity chromatography with the beads of microsomal proteins from rat liver showed that Bip and HSP70 associated to laminin chains and dissociated upon ATP hydrolysis. Protein-disulfide isomerase also showed affinity to the column. GRP94 and calnexin showed strong affinity and were washed out only with a detergent solution. Thus, many molecular chaperones are suggested to be involved in the intracellular assembly of laminin chains.
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Ip JJK, Hui PKT, Chau MT, Lam WWM. Merosin-deficient congenital muscular dystrophy (MDCMD): a case report with MRI, MRS and DTI findings. J Radiol Case Rep 2012; 6:1-7. [PMID: 23365711 DOI: 10.3941/jrcr.v6i8.997] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Congenital muscular dystrophy (CMD) comprises a heterogeneous group of disorders present at birth with muscle weakness, hypotonia and contractures. Congenital muscular dystrophy (CMD) comprises a heterogeneous group of disorders with muscle weakness, hypotonia and contractures present at birth. A particular subset of classic CMD is characterized by a complete absence of merosin. Merosin-deficient congenital muscular dystrophy (MDCMD) is a rare genetic disease involving the central and peripheral nervous system in the childhood. High signal intensities are often observed throughout the centrum semiovale, periventricular, and sub-cortical white matters on T2-weighted images in MRI brain in children with MDCMD. Apparent diffusion coefficient (ADC) map may reveal increased signal intensity and apparent diffusion coefficient values in the periventricular and deep white matters. These white matter findings, observed in late infancy, decrease in severity with age. The pathogenesis of these changes remains uncertain at present. In this article, we outline the specific MR imaging findings seen in a patient with documented MDCMD and also suggest the causes.
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Affiliation(s)
- Janice J K Ip
- Department of Radiology, Queen Mary Hospital, Hong Kong West Cluster, HKSAR, China.
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16
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LSHGD: a database for human leprosy susceptible genes. Genomics 2012; 100:162-6. [PMID: 22750101 DOI: 10.1016/j.ygeno.2012.06.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Revised: 05/23/2012] [Accepted: 06/23/2012] [Indexed: 01/25/2023]
Abstract
Studies aiming to explore the involvement of host genetic factors to determine susceptibility to develop disease and individual's response to the infection with Mycobacterium leprae have increased in recent years. To address this issue, we have developed a Leprosy Susceptible Human Gene Database (LSHGD) to integrate leprosy and human associated 45 genes by profound literature search. This will serve as a user-friendly and interactive platform to understand the involvement of human polymorphisms (SNPs) in leprosy, independent genetic control over both susceptibility to leprosy and its association with multi-drug resistance of M. leprae. As the first human genetic database in leprosy it aims to provide information about the associated genes, corresponding protein sequences, available three dimensional structures and polymorphism related to leprosy. In conclusion, this will serve as a multifunctional valuable tool and convenient information platform which is freely available at http://www.vit.ac.in/leprosy/leprosy.htm and enables the user to retrieve information of their interest.
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Kumagai C, Okano M, Kitagawa Y. Three heterotrimeric laminins produced by human keratinocytes. Cytotechnology 2011; 33:167-74. [PMID: 19002824 DOI: 10.1023/a:1008186912975] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Laminins are a family of glycoproteins composed of alpha,beta and gamma chains. Five alpha(alpha1-alpha5), three beta (beta1-beta3) and twogamma (gamma1 and gamma2) chains have been cloned fromhuman and their replaceable assembly into heterotrimers producesthe variety of laminins. Reverse transcription-polymerase chainreaction of mRNAs showed that human keratinocytes express thealpha3, alpha5, beta1, beta3, gamma1 andgamma2 genes at high level among the ten cloned lamininchains. Western blot and immunoprecipitation of the cell lysatewith antiserum directed against mouse laminin-1(alpha1beta1gamma1) detected two trimers with thecomposition of alphaxbeta1gamma1 (probablylaminin-10 with the composition of alpha5beta1gamma1and alphaybeta1gamma1. Meanwhile, antiserum directedagainst a synthetic peptide of human alpha3 detected onlyalpha3beta3gamma2 trimer (laminin-5). We thus show thatkeratinocytes produce three heterotrimeric laminins. We couldnot detect the assembly of alpha3 with beta1 and gamma1chains to form alpha3beta1gamma1 (laminin-6) in keratinocytes.
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Affiliation(s)
- C Kumagai
- Graduate Program of Biochemical Regulation, Graduate School of Bioagricultural Sciences, Nagoya University, Japan
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19
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Reed UC. Congenital muscular dystrophy. Part II: a review of pathogenesis and therapeutic perspectives. ARQUIVOS DE NEURO-PSIQUIATRIA 2010; 67:343-62. [PMID: 19547838 DOI: 10.1590/s0004-282x2009000200035] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2008] [Accepted: 03/14/2009] [Indexed: 11/22/2022]
Abstract
The congenital muscular dystrophies (CMDs) are a group of genetically and clinically heterogeneous hereditary myopathies with preferentially autosomal recessive inheritance, that are characterized by congenital hypotonia, delayed motor development and early onset of progressive muscle weakness associated with dystrophic pattern on muscle biopsy. The clinical course is broadly variable and can comprise the involvement of the brain and eyes. From 1994, a great development in the knowledge of the molecular basis has occurred and the classification of CMDs has to be continuously up dated. In the last number of this journal, we presented the main clinical and diagnostic data concerning the different subtypes of CMD. In this second part of the review, we analyse the main reports from the literature concerning the pathogenesis and the therapeutic perspectives of the most common subtypes of CMD: MDC1A with merosin deficiency, collagen VI related CMDs (Ullrich and Bethlem), CMDs with abnormal glycosylation of alpha-dystroglycan (Fukuyama CMD, Muscle-eye-brain disease, Walker Warburg syndrome, MDC1C, MDC1D), and rigid spine syndrome, another much rare subtype of CMDs not related with the dystrophin/glycoproteins/extracellular matrix complex.
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Warburton D, El-Hashash A, Carraro G, Tiozzo C, Sala F, Rogers O, De Langhe S, Kemp PJ, Riccardi D, Torday J, Bellusci S, Shi W, Lubkin SR, Jesudason E. Lung organogenesis. Curr Top Dev Biol 2010; 90:73-158. [PMID: 20691848 DOI: 10.1016/s0070-2153(10)90003-3] [Citation(s) in RCA: 290] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Developmental lung biology is a field that has the potential for significant human impact: lung disease at the extremes of age continues to cause major morbidity and mortality worldwide. Understanding how the lung develops holds the promise that investigators can use this knowledge to aid lung repair and regeneration. In the decade since the "molecular embryology" of the lung was first comprehensively reviewed, new challenges have emerged-and it is on these that we focus the current review. Firstly, there is a critical need to understand the progenitor cell biology of the lung in order to exploit the potential of stem cells for the treatment of lung disease. Secondly, the current familiar descriptions of lung morphogenesis governed by growth and transcription factors need to be elaborated upon with the reinclusion and reconsideration of other factors, such as mechanics, in lung growth. Thirdly, efforts to parse the finer detail of lung bud signaling may need to be combined with broader consideration of overarching mechanisms that may be therapeutically easier to target: in this arena, we advance the proposal that looking at the lung in general (and branching in particular) in terms of clocks may yield unexpected benefits.
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Affiliation(s)
- David Warburton
- The Saban Research Institute, Childrens Hospital Los Angeles, Los Angeles, California, USA
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21
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Dynamics of extracellular matrix in ovarian follicles and corpora lutea of mice. Cell Tissue Res 2009; 339:613-24. [PMID: 20033213 PMCID: PMC2831189 DOI: 10.1007/s00441-009-0905-8] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2009] [Accepted: 11/02/2009] [Indexed: 01/15/2023]
Abstract
Despite the mouse being an important laboratory species, little is known about changes in its extracellular matrix (ECM) during follicle and corpora lutea formation and regression. Follicle development was induced in mice (29 days of age/experimental day 0) by injections of pregnant mare’s serum gonadotrophin on days 0 and 1 and ovulation was induced by injection of human chorionic gonadotrophin on day 2. Ovaries were collected for immunohistochemistry (n=10 per group) on days 0, 2 and 5. Another group was mated and ovaries were examined on day 11 (n=7). Collagen type IV α1 and α2, laminin α1, β1 and γ1 chains, nidogens 1 and 2 and perlecan were present in the follicular basal lamina of all developmental stages. Collagen type XVIII was only found in basal lamina of primordial, primary and some preantral follicles, whereas laminin α2 was only detected in some preantral and antral follicles. The focimatrix, a specialised matrix of the membrana granulosa, contained collagen type IV α1 and α2, laminin α1, β1 and γ1 chains, nidogens 1 and 2, perlecan and collagen type XVIII. In the corpora lutea, staining was restricted to capillary sub-endothelial basal laminas containing collagen type IV α1 and α2, laminin α1, β1 and γ1 chains, nidogens 1 and 2, perlecan and collagen type XVIII. Laminins α4 and α5 were not immunolocalised to any structure in the mouse ovary. The ECM composition of the mouse ovary has similarities to, but also major differences from, other species with respect to nidogens 1 and 2 and perlecan.
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22
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Gutiérrez-Fernández A, Gingles NA, Bai H, Castellino FJ, Parmer RJ, Miles LA. Plasminogen enhances neuritogenesis on laminin-1. J Neurosci 2009; 29:12393-400. [PMID: 19812315 PMCID: PMC2789650 DOI: 10.1523/jneurosci.3553-09.2009] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2009] [Accepted: 08/13/2009] [Indexed: 11/21/2022] Open
Abstract
Proteins of the plasminogen activation system are broadly expressed throughout the nervous system, and key roles for these proteins in neuronal function have been demonstrated. Recent reports have established that plasminogen is synthesized in neuroendocrine tissues, making this protein and the proteolytic activity of the product of its activation, plasmin, available at sites separated anatomically from circulating, hepatocyte-derived plasminogen. Results with plasminogen-deficient humans and mice suggest a role for plasminogen in neuritogenesis. To elucidate the role of the plasminogen activation system in these processes, the function of plasminogen during neuritogenesis and neurite outgrowth was studied. It is shown here that plasminogen participates in neuritogenesis, as plasmin inhibitors reduced both neurite outgrowth and neurite length in PC-12 cells. The addition of exogenous plasminogen enhanced neurite outgrowth and neurite length in both PC-12 cells and primary cortical neurons. The proteolytic activity of plasmin was required, since mutation of the catalytic serine residue completely abolished the stimulatory activity. Furthermore, mutation of the lysine binding site within kringle 5 of the plasminogen molecule also reduced the neuritogenic activity of plasminogen. Additionally, we demonstrate that plasminogen specifically bound to laminin-1, the interaction resulted in increased plasminogen activation by tissue-type plasminogen activator, and was dependent on a functional lysine binding site within plasminogen kringle 5. Moreover, during NGF-induced neuritogenesis, laminin-1 was degraded, and this cleavage was catalyzed by plasmin. This study provides the first direct evidence that plasminogen participates in neurite outgrowth and also suggests that laminin-1 degradation by plasmin contributes to the process of neuritogenesis.
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Affiliation(s)
- Ana Gutiérrez-Fernández
- Department of Cell Biology, Division of Vascular Biology, The Scripps Research Institute, La Jolla, California 92037
| | - Neill A. Gingles
- Department of Medicine, University of California, San Diego, and Veterans Administration San Diego Healthcare System, San Diego, California 92161, and
| | - Hongdong Bai
- Department of Medicine, University of California, San Diego, and Veterans Administration San Diego Healthcare System, San Diego, California 92161, and
| | - Francis J. Castellino
- W. M. Keck Center for Transgene Research, University of Notre Dame, Notre Dame, Indiana 46556
| | - Robert J. Parmer
- Department of Medicine, University of California, San Diego, and Veterans Administration San Diego Healthcare System, San Diego, California 92161, and
| | - Lindsey A. Miles
- Department of Cell Biology, Division of Vascular Biology, The Scripps Research Institute, La Jolla, California 92037
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Jung SY, Kim JM, Kang HK, Jang DH, Min BM. A biologically active sequence of the laminin alpha2 large globular 1 domain promotes cell adhesion through syndecan-1 by inducing phosphorylation and membrane localization of protein kinase Cdelta. J Biol Chem 2009; 284:31764-75. [PMID: 19762914 DOI: 10.1074/jbc.m109.038547] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Laminin-2 promotes basement membrane assembly and peripheral myelinogenesis; however, a receptor-binding motif within laminin-2 and the downstream signaling pathways for motif-mediated cell adhesion have not been fully established. The human laminin-2 alpha2 chain cDNAs cloned from human keratinocytes and fibroblasts correspond to the laminin alpha2 chain variant sequence from the human brain. Individually expressed recombinant large globular (LG) 1 protein promotes cell adhesion and has heparin binding activities. Studies with synthetic peptides delineate the DLTIDDSYWYRI motif (Ln2-P3) within the LG1 as a major site for both heparin and cell binding. Cell adhesion to LG1 and Ln2-P3 is inhibited by treatment of heparitinase I and chondroitinase ABC. Syndecan-1 from PC12 cells binds to LG1 and Ln2-P3 and colocalizes with both molecules. Suppression of syndecan-1 with RNA interference inhibits cell adhesion to LG1 and Ln2-P3. The binding of syndecan-1 with LG1 and Ln2-P3 induces the recruitment of protein kinase Cdelta (PKCdelta) into the membrane and stimulates its tyrosine phosphorylation. A decrease in PKCdelta activity significantly reduces cell adhesion to LG1 and Ln2-P3. Taken together, these results indicate that the Ln2-P3 motif and LG1 domain, containing the motif, within the human laminin-2 alpha2 chain are major ligands for syndecan-1, which mediates cell adhesion through the PKCdelta signaling pathway.
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Affiliation(s)
- Sung Youn Jung
- Department of Oral Biochemistry and Program of Craniomaxillofacial Reconstruction Science, Dental Research Institute, Intellectual Biointerface Engineering Center, BK21 CLS, Seoul National University School of Dentistry, Seoul 110-749, Korea
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Takashima S, Yasuo M, Sanzen N, Sekiguchi K, Okabe M, Yoshida T, Toda A, Nikaido T. Characterization of laminin isoforms in human amnion. Tissue Cell 2008; 40:75-81. [DOI: 10.1016/j.tice.2007.09.001] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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25
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Ocampo JSP, Brito JMD, Corrêa-de-Santana E, Borojevic R, Villa-Verde DMS, Savino W. Laminin-211 controls thymocyte—thymic epithelial cell interactions. Cell Immunol 2008; 254:1-9. [DOI: 10.1016/j.cellimm.2008.06.005] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2008] [Revised: 06/04/2008] [Accepted: 06/05/2008] [Indexed: 10/21/2022]
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26
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Teller IC, Auclair J, Herring E, Gauthier R, Ménard D, Beaulieu JF. Laminins in the developing and adult human small intestine: relation with the functional absorptive unit. Dev Dyn 2007; 236:1980-90. [PMID: 17503455 DOI: 10.1002/dvdy.21186] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The expression of the five laminin alpha-chains was analyzed in the developing and mature human small intestine at the protein and transcript levels in order to further delineate specific involvement of individual laminins in relation to the epithelial cell state as defined along the functional crypt-villus axis. The results show that all of the alpha-laminin transcripts are expressed in significant amounts in the small intestine relative to a panel of other tissues and organs. Further analysis of their expression by indirect immunofluorescence and semi-quantitative and quantitative RT-PCR demonstrates a close correlation between transcript and protein expression, distinct epithelial and mesenchymal origins, as well as differential occurrence in intestinal basement membranes according to developmental stage, along the crypt-villus axis and in compartment-related experimental intestinal cell models. Taken together, the data point out the prime importance of alpha2-, alpha3-, and alpha5-containing laminins for the development and maintenance of the functional human intestinal epithelium.
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Affiliation(s)
- Inga C Teller
- CIHR Team on Digestive Epithelium, Département d'anatomie et de biologie cellulaire, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec, Canada
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27
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Lisi MT, Cohn RD. Congenital muscular dystrophies: new aspects of an expanding group of disorders. Biochim Biophys Acta Mol Basis Dis 2006; 1772:159-72. [PMID: 17097859 DOI: 10.1016/j.bbadis.2006.09.006] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2006] [Revised: 09/11/2006] [Accepted: 09/13/2006] [Indexed: 12/24/2022]
Abstract
The congenital muscular dystrophies comprise a genetically and clinically heterogeneous group of disorders characterized by early onset of progressive muscle weakness and often involvement of other organ systems such as the brain and eyes. During the last decade, significant progress has been made to further characterize various forms of congenital muscular dystrophies based on their specific genetic and clinical appearance. This review represents an overview of the recent accomplishments as they relate to clinical, diagnostic, pathogenetic and therapeutic aspects of congenital muscular dystrophies.
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Affiliation(s)
- Matthew T Lisi
- McKusick-Nathans Institute of Genetic Medicine, Department of Pediatrics and Neurology, Johns Hopkins University School of Medicine, 600 N Wolfe Street, Blalock 1008 Baltimore, MD 21287, USA
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Dowgiert J, Sosne G, Kurpakus-Wheater M. Laminin-2 stimulates the proliferation of epithelial cells in a conjunctival epithelial cell line. Cell Prolif 2004; 37:161-75. [PMID: 15030550 PMCID: PMC6496726 DOI: 10.1111/j.1365-2184.2004.00292.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Laminin-2 (LN-2, alpha2beta1gamma1) is a basement membrane-associated laminin isoform usually considered in the context of muscle and nerve tissues. To test the hypothesis that LN-2 can additionally modulate epithelial cell biology, an analysis of the role of LN-2 in cell adhesion, activation of signalling intermediates and proliferation was undertaken. A virally transformed human conjunctival epithelial cell line (HC0597) was utilized in this study. Adhesion assays using function-inhibiting antibodies demonstrated that alpha3beta1 integrin is essential for the rapid attachment of conjunctival epithelial cells to LN-2. Bromodeoxyuridine (BrdU) incorporation analyses revealed that, compared with LN-1 or LN-10, LN-2 significantly promotes epithelial proliferation. Phosphorylation of the signalling intermediates Erk1/2 and Akt-1 was observed within 15 min of cell adhesion to LN-2. Inhibiting alpha3beta1 integrin function decreased total cellular phosphotyrosine levels, specifically inhibited phosphorylation of Erk1/2 and Akt-1, and dampened the proliferation response of epithelial cells adherent to LN-2. Inhibition of Erk or Akt activation inhibited cell proliferation in a dose-dependent manner. However, the inhibition of Erk resulted in a stronger suppression of proliferation compared with Akt inhibition. From these results, it is concluded that human conjunctival epithelial cells adhere to immobilized LN-2 using alpha3beta1 integrin. alpha3beta1 integrin/LN-2 signalling, transduced primarily through an Erk pathway, enhances epithelial cell proliferation. These results demonstrate that LN-2 can impact on epithelial cell biology in addition to nerve and muscle, and provide information regarding the role of this isoform in ocular surface epithelial cells.
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Affiliation(s)
- J Dowgiert
- Department of Anatomy and Cell Biology, Wayne State University School of Medicine, Detroit, MI 48201, USA
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Di Muzio A, De Angelis MV, Di Fulvio P, Ratti A, Pizzuti A, Stuppia L, Gambi D, Uncini A. Dysmyelinating sensory-motor neuropathy in merosin-deficient congenital muscular dystrophy. Muscle Nerve 2003; 27:500-6. [PMID: 12661054 DOI: 10.1002/mus.10326] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A 20-year-old man with mild myopathy, external ophthalmoparesis, epilepsy, and diffuse white matter hyperintensity in the brain on magnetic resonance imaging had partial merosin deficiency in muscle and absent merosin in the endoneurium. Motor and sensory nerve conduction velocities were slow. Nerve biopsy showed reduction of large myelinated fibers, short internodes, enlarged nodes, excessive variability of myelin thickness, tomacula, and uncompacted myelin, but no evidence of segmental demyelination, naked axons, or onion bulbs. Thus, in congenital muscular dystrophy, merosin expression may be dissociated in different tissues, and the neuropathy is sensory-motor and due to abnormal myelinogenesis.
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Affiliation(s)
- A Di Muzio
- Center for Neuromuscular Diseases, University G. d'Annunzio, Chieti, Italy
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30
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Guo LT, Zhang XU, Kuang W, Xu H, Liu LA, Vilquin JT, Miyagoe-Suzuki Y, Takeda S, Ruegg MA, Wewer UM, Engvall E. Laminin alpha2 deficiency and muscular dystrophy; genotype-phenotype correlation in mutant mice. Neuromuscul Disord 2003; 13:207-15. [PMID: 12609502 DOI: 10.1016/s0960-8966(02)00266-3] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Deficiency of laminin alpha2 is the cause of one of the most severe muscular dystrophies in humans and other species. It is not yet clear how particular mutations in the laminin alpha2 chain gene affect protein expression, and how abnormal levels or structure of the protein affect disease. Animal models may be valuable for such genotype-phenotype analysis and for determining mechanism of disease as well as function of laminin. Here, we have analyzed protein expression in three lines of mice with mutations in the laminin alpha2 chain gene and in two lines of transgenic mice overexpressing the human laminin alpha2 chain gene in skeletal muscle. The dy(3K)/dy(3K) experimental mutant mice are completely deficient in laminin alpha2; the dy/dy spontaneous mutant mice have small amounts of apparently normal laminin; and the dy(W)/dy(W) mice express even smaller amounts of a truncated laminin alpha2, lacking domain VI. Interestingly, all mutants lack laminin alpha2 in peripheral nerve. We have demonstrated previously, that overexpression of the human laminin alpha2 in skeletal muscle in dy(2J)/dy(2J) and dy(W)/dy(W) mice under the control of a striated muscle-specific creatine kinase promoter substantially prevented the muscular dystrophy in these mice. However, dy(W)/dy(W) mice, expressing the human laminin alpha2 under the control of the striated muscle-specific portion of the desmin promoter, still developed muscular dystrophy. This failure to rescue is apparently because of insufficient production of laminin alpha2. This study provides additional evidence that the amount of laminin alpha2 is most critical for the prevention of muscular dystrophy. These data may thus be of significance for attempts to treat congenital muscular dystrophy in human patients.
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Affiliation(s)
- L T Guo
- The Burnham Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA
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31
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Yurchenco PD, Smirnov S, Mathus T. Analysis of basement membrane self-assembly and cellular interactions with native and recombinant glycoproteins. Methods Cell Biol 2003; 69:111-44. [PMID: 12070988 DOI: 10.1016/s0091-679x(02)69010-7] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Peter D Yurchenco
- Department of Pathology and Laboratory Medicine, Robert Wood Johnson Medical School, Piscataway, New Jersey 08854, USA
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32
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Tezak Z, Prandini P, Boscaro M, Marin A, Devaney J, Marino M, Fanin M, Trevisan CP, Park J, Tyson W, Finkel R, Garcia C, Angelini C, Hoffman EP, Pegoraro E. Clinical and molecular study in congenital muscular dystrophy with partial laminin alpha 2 (LAMA2) deficiency. Hum Mutat 2003; 21:103-11. [PMID: 12552556 DOI: 10.1002/humu.10157] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Complete laminin alpha2 (LAMA2) deficiency causes approximately half of congenital muscular dystrophy (CMD) cases. Many loss-of-function mutations have been reported in these severe, neonatal-onset patients, but only single missense mutations have been found in milder CMD with partial laminin alpha2 deficiency. Here, we studied nine patients diagnosed with CMD who showed abnormal white-matter signal at brain MRI and partial deficiency of laminin alpha2 on immunofluorescence of muscle biopsy. We screened the entire 9.5 kb laminin alpha2 mRNA from patient muscle biopsy by direct capillary automated sequencing, single strand conformational polymorphism (SSCP), or denaturing high performance liquid chromatography (DHPLC) of overlapping RT-PCR products followed by direct sequencing of heteroduplexes. We identified laminin alpha2 sequence changes in six of nine CMD patients. Each of the gene changes identified, except one, was novel, including three missense changes and two splice-site mutations. The finding of partial laminin alpha2 deficiency by immunostaining is not specific for laminin alpha2 gene mutation carriers, with only two patients (22%) showing clear causative mutations, and an additional three patients (33%) showing possible mutations. The clinical presentation and disease progression was homogeneous in the laminin alpha2-mutation positive and negative CMD patients.
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Affiliation(s)
- Zivana Tezak
- Research Center for Genetic Medicine, Children's Research Hospital, Washington, DC, USA
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33
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Abstract
A Turkish patient with cobblestone lissencephaly and eye involvement without characteristic muscular changes for congenital muscular dystrophy died at the age of 3 months presented with neonatal apneic periods and generalized seizures. Serum creatine kinase level, electromyography, chromosome analysis and blood biochemistry were normal. Unilateral microphthalmia, retinal dysplasia and internal strabismus were the ocular findings. Magnetic resonance imaging clearly demonstrated the thickened, irregular, nearly agyric cobblestone cerebral cortex with underlying unmyelinated white matter, hydrocephalus, hypoplastic corpus callosum, brain stem and cerebellum with retrocerebellar cyst and posterior cephalocele.
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Affiliation(s)
- Yüksel Pabuşçu
- Department of Radiology, Gülhane Military Medical Academy, 06010, Ankara, Turkey
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34
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Petäjäniemi N, Korhonen M, Kortesmaa J, Tryggvason K, Sekiguchi K, Fujiwara H, Sorokin L, Thornell LE, Wondimu Z, Assefa D, Patarroyo M, Virtanen I. Localization of laminin alpha4-chain in developing and adult human tissues. J Histochem Cytochem 2002; 50:1113-30. [PMID: 12133914 DOI: 10.1177/002215540205000813] [Citation(s) in RCA: 82] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Recent studies suggest important functions for laminin-8 (Ln-8; alpha4beta1gamma1) in vascular and blood cell biology, but its distribution in human tissues has remained elusive. We have raised a monoclonal antibody (MAb) FC10, and by enzyme-linked immunoassay (EIA) and Western blotting techniques we show that it recognizes the human Ln alpha4-chain. Immunoreactivity for the Ln alpha4-chain was localized in tissues of mesodermal origin, such as basement membranes (BMs) of endothelia, adipocytes, and skeletal, smooth, and cardiac muscle cells. In addition, the Ln alpha4-chain was found in regions of some epithelial BMs, including epidermis, salivary glands, pancreas, esophageal and gastric glands, intestinal crypts, and some renal medullary tubules. Developmental differences in the distribution of Ln alpha4-chain were detected in skeletal muscle, walls of vessels, and intestinal crypts. Ln alpha4- and Ln alpha2-chains co-localized in BMs of fetal skeletal muscle cells and in some epithelial BMs, e.g., in gastric glands and acini of pancreas. Cultured human pulmonary artery endothelial (HPAE) cells produced Ln alpha4-chain as M(r) 180,000 and 200,000 doublet and rapidly deposited it to the growth substratum. In cell-free extracellular matrices of human kidney and lung, Ln alpha4-chain was found as M(r) 180,000 protein.
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Affiliation(s)
- Noora Petäjäniemi
- Institute of Biomedicine/Anatomy, Biomedicum Helsinki, University of Helsinki, Helsinki, Finland.
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35
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Wibawa T, Soebono H, Matsuo M. Association of a missense mutation of the laminin alpha2 gene with tuberculoid type of leprosy in Indonesian patients. Trop Med Int Health 2002; 7:631-6. [PMID: 12100448 DOI: 10.1046/j.1365-3156.2002.00908.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Leprosy, an infection caused by Mycobacterium leprae, has a specific tropism for the myelinating Schwann cells of peripheral nerves. Recently, the G domain of laminin alpha2 has been shown to be a mediator for M. leprae to bind to alpha-dystroglycan in Schwann cells. In order to analyse the association of leprosy with the mediator, three genetic polymorphisms encoding the G domain of the laminin alpha2 chain were analysed by direct sequencing in 53 leprosy patients and 58 healthy contact individuals from Indonesia. There was no significant difference in the incidence of the polymorphisms between patients and non-patients. Remarkably, it was found that a missense mutation (T7809C) substituting valine with alanine (V2587A) was found to be more frequent in the tuberculoid type than in the lepromatous type leprosy. It is supposed that this missense mutation is one of the determinant factors in the early onset of peripheral nerve damage in Indonesian tuberculoid leprosy patients.
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Affiliation(s)
- Tri Wibawa
- Division of Molecular Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
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36
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Smirnov SP, McDearmon EL, Li S, Ervasti JM, Tryggvason K, Yurchenco PD. Contributions of the LG modules and furin processing to laminin-2 functions. J Biol Chem 2002; 277:18928-37. [PMID: 11886875 DOI: 10.1074/jbc.m201880200] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The alpha2-laminin subunit contributes to basement membrane functions in muscle, nerve, and other tissues, and mutations in its gene are causes of congenital muscular dystrophy. The alpha2 G-domain modules, mutated in several of these disorders, are thought to mediate different cellular interactions. To analyze these contributions, we expressed recombinant laminin-2 (alpha(2)beta(1)gamma(1)) with LG4-5, LG1-3, and LG1-5 modular deletions. Wild-type and LG4-5 deleted-laminins were isolated from medium intact and cleaved within LG3 by a furin-like convertase. Myoblasts adhered predominantly through LG1-3 while alpha-dystroglycan bound to both LG1-3 and LG4-5. Recombinant laminin stimulated acetylcholine receptor (AChR) clustering; however, clustering was induced only by the proteolytic processed form, even in the absence of LG4-5. Furthermore, clustering required alpha(6)beta(1) integrin and alpha-dystroglycan binding activities available on LG1-3, acting in concert with laminin polymerization. The ability of the modified laminins to mediate basement membrane assembly was also evaluated in embryoid bodies where it was found that both LG1-3 and LG4-5, but not processing, were required. In conclusion, there is a division of labor among LG-modules in which (i) LG4-5 is required for basement membrane assembly but not for AChR clustering, and (ii) laminin-induced AChR clustering requires furin cleavage of LG3 as well as alpha-dystroglycan and alpha(6)beta(1) integrin binding.
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Affiliation(s)
- Sergei P Smirnov
- Department of Pathology & Laboratory Medicine, Robert Wood Johnson Medical School, Piscataway, New Jersey 08854, USA
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37
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Sasaki T, Giltay R, Talts U, Timpl R, Talts JF. Expression and distribution of laminin alpha1 and alpha2 chains in embryonic and adult mouse tissues: an immunochemical approach. Exp Cell Res 2002; 275:185-99. [PMID: 11969289 DOI: 10.1006/excr.2002.5499] [Citation(s) in RCA: 91] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Protein levels, mRNA expression, and localization of laminin alpha1 and alpha2 chains in development and in adult mice were examined. Recombinant fragments were used to obtain high-titer-specific polyclonal antibodies for establishing quantitative radioimmuno-inhibition assays. This often demonstrated an abundance of alpha2 chain, but also distinct amounts of alpha1 chain for adult tissues. The highest amounts of alpha1 were found in placenta, kidney, testis, and liver and exceeded those of alpha2. All other tissue extracts showed a higher content of alpha2, which was particularly high in heart and muscle when compared to alpha1. Content of gamma1 chain, shared by most laminins, was also analyzed. This demonstrated gamma1 chain levels being equal to or moderately exceeding the sum of alpha1 and alpha2 chains, indicating that these isoforms represent the major known laminin isoforms in most adult mouse tissues so far examined. Moreover, we found good correlation between radioimmuno-inhibition data and mRNA levels of adult tissues as measured by quantitative real-time reverse transcriptase-PCR. Embryonic tissues were also analyzed by radioimmuno-inhibition assays. This demonstrated for day 11 embryos comparable amounts of alpha1 and gamma1 and a more than 25-fold lower content of alpha2. This content increased to about 10% of alpha1 in day 13 embryos. The day 18 embryo showed in heart, kidney, and liver, but not yet in brain and lung, alpha1/alpha2 chain ratios comparable to those in adult tissues. Immunostaining demonstrated alpha1 in Reichert's membrane (day 7.5), while alpha2 could not be detected before day 11.5. These data were compared with immunohistochemical localization results on several more embryonic and adult tissue sections. Our results regarding localization are consistent with those of earlier work with some notable exceptions. This was in part due to epitope masking for monoclonal antibodies commonly used in previous studies in esophagus, intestine, stomach, liver, kidney, and spleen.
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Affiliation(s)
- Takako Sasaki
- Max-Planck-Institute for Biochemistry, Martinsried, D-82152, Germany
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38
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Gilhuis HJ, ten Donkelaar HJ, Tanke RB, Vingerhoets DM, Zwarts MJ, Verrips A, Gabreëls FJM. Nonmuscular involvement in merosin-negative congenital muscular dystrophy. Pediatr Neurol 2002; 26:30-6. [PMID: 11814732 DOI: 10.1016/s0887-8994(01)00352-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The spectrum of nonmuscular involvement in six children with merosin-negative congenital muscular dystrophy is described. In all children, biochemical, neuroradiologic, cardiac, and neurophysiologic studies were performed. Cerebral structures that were myelinated at gestation, including internal capsule, corpus callosum, brainstem, and cerebellar white matter, demonstrated no abnormalities, whereas the periventricular and subcortical white matter, which were myelinated in the first postnatal year, demonstrated signs of leukoencephalopathy. Cerebrospinal fluid analysis revealed an elevated albumin cerebrospinal fluid to serum ratio in the younger children. Electroencephalogram results were abnormal in the two elder children. One child suffered from congestive cardiomyopathy. The increase in nerve conduction velocity in these children over the years lagged behind those of healthy patients, pointing to a demyelinating neuropathy. We conclude that in merosin-negative congenital muscular dystrophy patients, nonmuscular involvement includes the central and peripheral nervous system and the heart. The pattern of myelination of the brain and nerve conduction slowing suggests a myelination arrest. Merosin deficiency can give rise to a congestive cardiomyopathy, which is of no clinical relevance in the majority of children.
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Affiliation(s)
- H Jacobus Gilhuis
- Department of Paediatric Neurology, Neuromuscular Centre, University Medical Centre St Radboud, 6500 HB Nijmegen, The Netherlands
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39
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Ozsarlak O, Schepens E, Parizel PM, Van Goethem JW, Vanhoenacker F, De Schepper AM, Martin JJ. Hereditary neuromuscular diseases. Eur J Radiol 2001; 40:184-97. [PMID: 11731207 DOI: 10.1016/s0720-048x(01)00399-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
This article presents the actual classification of neuromuscular diseases based on present expansion of our knowledge and understanding due to genetic developments. It summarizes the genetic and clinical presentations of each disorder together with CT findings, which we studied in a large group of patients with neuromuscular diseases. The muscular dystrophies as the largest and most common group of hereditary muscle diseases will be highlighted by giving detailed information about the role of CT and MRI in the differential diagnosis. The radiological features of neuromuscular diseases are atrophy, hypertrophy, pseudohypertrophy and fatty infiltration of muscles on a selective basis. Although the patterns and distribution of involvement are characteristic in some of the diseases, the definition of the type of disease based on CT scan only is not always possible.
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Affiliation(s)
- O Ozsarlak
- Department of Radiology, University Hospital Antwerp, Wilrijkstraat 10, B-2650 Edegem, Belgium.
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40
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Torimura T, Ueno T, Kin M, Harad R, Nakamura T, Sakamoto M, Kumashiro R, Yano H, Kojiro M, Sata M. Laminin deposition to type IV collagen enhances haptotaxis, chemokinesis, and adhesion of hepatoma cells through beta1-integrins. J Hepatol 2001; 35:245-53. [PMID: 11580147 DOI: 10.1016/s0168-8278(01)00127-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
BACKGROUND/AIMS In hepatocellular carcinoma, laminin deposition to type IV collagen along the sinusoids is observed with the development of arterial network, coinciding with intrahepatic metastasis. We investigated the influence of laminin deposition to type IV collagen on hepatoma cell adhesion, motility and secretion of matrix metalloproteinases (MMPs), which are indispensable behaviors for tumor metastasis. METHODS Hepatoma cell lines (KYN-1, -2 and -3) were used. The expression of integrin subunit mRNAs in hepatoma cells was confirmed by RT-PCR. The influence of laminin addition to type IV collagen on the adhesion, chemokinesis, and migration of KYN-1, -2 and -3 was evaluated by the haptotactic migration, phagokinetic track motility, and cell adhesion assays. The effects of integrin subunits on these activities were evaluated using the function-blocking antibodies for integrins. Phosphorylation of MEK1/2 and secretion of MMPs were investigated by Western blotting and gelatin zymography. RESULTS Integrin alpha1, alpha2, alpha3, alpha6 and beta1 subunit mRNAs were detected. The combination of type IV collagen and laminin enhanced the migration, chemokinesis, and adhesion of hepatoma cells compared to that of type IV collagen when used alone. The enhanced activity was significantly suppressed by function-blocking antibodies for integrin alpha1, alpha2, alpha3, alpha6 and beta1 subunits. Hepatoma cells cultured on the combination of type IV collagen and laminin showed phosphorylation of MEK1/2 and increased secretion of MMPs. CONCLUSIONS The addition of laminin to type IV collagen enhances hepatoma cell adhesion and motility through beta1-integrins.
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Affiliation(s)
- T Torimura
- The Second Department of Medicine, Kurume University School of Medicine, Japan.
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41
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Fujiwara H, Kikkawa Y, Sanzen N, Sekiguchi K. Purification and characterization of human laminin-8. Laminin-8 stimulates cell adhesion and migration through alpha3beta1 and alpha6beta1 integrins. J Biol Chem 2001; 276:17550-8. [PMID: 11278628 DOI: 10.1074/jbc.m010155200] [Citation(s) in RCA: 136] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Recently identified laminin isoforms containing the alpha4 chain have been shown to be expressed in the basement membrane of restricted organs such as heart, skeletal muscle, and blood vessels, especially those in embryos. We screened 38 human cell lines for the expression of the laminin alpha4 chain by reverse transcriptase-polymerase chain reaction and found that T98G glioblastoma cells express only alpha4, but not other alpha chains. Laminin-8, an isoform containing the alpha4 and beta1 chains, was purified from conditioned medium of T98G cells by gel filtration and immunoaffinity chromatography using a monoclonal antibody against laminin beta1 chain. The purified laminin isoform was composed of disulfide-linked 230-, 220-, and 200-kDa subunits, which immunoblot analysis identified as the beta1, gamma1, and alpha4 chains. Purified laminin-8 had cell adhesive activity comparable to laminin-1 but significantly weaker than laminin-5 and laminin-10/11. T98G cells adhering to laminin-8 became more elongated than those adhering to other laminin isoforms and extended multiple pseudopods. Cell adhesion to laminin-8 was abolished by an antibody against the integrin beta1 subunit or a combination of antibodies against the integrin alpha3 and alpha6 subunits, but not by either anti-alpha3 or anti-alpha6 antibody alone, suggesting that both alpha3beta1 and alpha6beta1 integrins serve as adhesion receptors for laminin-8. Consistent with these observations, K562 erythroleukemic cells transfected with either integrin alpha3 or alpha6 cDNA were capable of adhering to laminin-8 when beta1 integrins were stimulated by the beta1-activating antibody 8A2. Despite its moderate cell adhesive activity, laminin-8 was significantly potent in promoting cell migration when compared with other laminin isoforms and fibronectin. Cell migration on laminin-8 was completely inhibited by a combination of antibodies against alpha3 and alpha6 integrins, and substantially inhibited by anti-alpha3 antibody alone, suggesting that laminin-8-mediated cell migration is predominantly mediated by alpha3beta1 integrin. Given its potency to stimulate cell migration and preferential localization to the basement membrane of capillaries and embryonic tissues, laminin-8 may play a role in processes requiring enhanced cell migration during development, wound healing, and angiogenesis.
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Affiliation(s)
- H Fujiwara
- Institute for Protein Research, Osaka University, 3-2 Yamadaoka, Suita, Osaka 565-0871, Japan
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42
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Liesi P, Fried G, Stewart RR. Neurons and glial cells of the embryonic human brain and spinal cord express multiple and distinct isoforms of laminin. J Neurosci Res 2001; 64:144-67. [PMID: 11288143 DOI: 10.1002/jnr.1061] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We have identified by immunocytochemistry, Western blotting, and RT-PCR the isoforms of laminin expressed by glial cells and neurons cultured from human embryonic brain and spinal cord. We show that most of the known laminins are present in human neurons and glial cells. Importantly, Western analysis demonstrates that the isoforms of laminin present in embryonic human brain differ from those expressed in human spinal cord. Neurons of the brain and spinal cord also express their distinct and characteristic isoforms of laminin compared to the glial cells of the same CNS regions. These results suggest that, in addition to the known laminins, several novel isoforms may exist in the human embryonic CNS. The observed differences between the isoforms of laminin in brain and spinal cord neurons and glial cells may result from primary structural changes or from posttranslational modifications, e.g., variations in glycosylation. Thus, identification of these novel laminins and determination of their function(s) should further our understanding of the mechanisms of aging, disease, and trauma in the human CNS.
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Affiliation(s)
- P Liesi
- The Brain Laboratory, Biomedicum Helsinki, Institute of Biomedicine, Department of Anatomy, University of Helsinki, Helsinki, Finland.
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43
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Filenius S, Hormia M, Rissanen J, Burgeson RE, Yamada Y, Araki-Sasaki K, Nakamura M, Virtanen I, Tervo T. Laminin synthesis and the adhesion characteristics of immortalized human corneal epithelial cells to laminin isoforms. Exp Eye Res 2001; 72:93-103. [PMID: 11133187 DOI: 10.1006/exer.2000.0933] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have studied the synthesis of laminins (Ln) and determined the specific integrins mediating the adhesion of immortalized human corneal epithelial cells to mouse Ln-1, and human Lns-5 and -10. Immunofluorescence microscopy of the cells demonstrated integrin alpha(2), alpha(3), alpha(6), beta(1)and beta(4)subunits, integrins alpha(6)and beta(4)being found in a typical 'leopard-skin' like manner. Immunoprecipitation studies showed that the cells produced alpha 3, beta 3 and gamma 2 chains of Ln-5, but not Lns-1 or -10. In culture Ln-5 was found as small plaques beneath the adhering cells within 1 hr, while in 4 hr widely spread Ln-5 plaques were observed in colocalization with beta(4)integrin subunit. By using a quantitative cell adhesion assay and function-blocking monoclonal antibodies we showed that integrin beta(1)subunit plays a role in mediating corneal epithelial cell adhesion to mouse Ln-1. However, none of the available function-blocking antibodies to integrin alpha-subunits inhibited the adhesion. Integrin alpha(3)beta(1)complex mediated the adhesion of corneal epithelial cells to human Lns-5 and -10. Integrin complex alpha(3)beta(1), as well as laminin alpha(3)chain, was also shown to mediate cell adhesion to newly produced endogenous Ln-5. The present results show that integrin alpha(3)beta(1)complex mediates the adhesion of corneal epithelial cells to Lns-5 and -10, while a yet unknown integrin alpha subunit appears to play a role in the adhesion to Ln-1. The results also show that among corneal basement membrane laminins, Ln-5 is synthetized by epithelial cells while Ln-10 may be a product of keratocytes.
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Affiliation(s)
- S Filenius
- Department of Anatomy, Institute of Biomedicine, University of Helsinki, Helsinki, Finland.
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44
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Abstract
Laminins are a family of disulfide-linked heterotrimeric proteins consisting of 3 different subunits termed α, β, and γ chains. Combinations of 11 characterized laminin subunits (α1-α5, β1-β3, and γ1-γ3) generate at least 12 laminin isoforms, which can serve different functions. Although expression of laminin in the hematopoietic microenvironment has been known for many years, the nature of the laminin isoforms present in the human bone marrow is poorly characterized. The present study attempts to clarify this issue. Reverse transcriptase–polymerase chain reaction analysis of human bone marrow stromal cells suggested the expression of many laminin isoforms in the marrow. Northern blot and immunoblot analysis, however, showed that laminin-8/9 and laminin-10/11 are the most abundant laminin isoforms synthesized by human bone marrow stromal cells. Other isoforms, if present, certainly play a minor role in the hematopoietic microenvironment. Functionally, laminin-10/11 preparations showed strong adhesive interactions with human CD34+ cell lines. Antibodies against the β1 integrin subunit inhibited these interactions. Other laminin isoforms, especially laminin-1 and laminin-2/4, showed only weak or no adhesive interactions with the hematopoietic cell lines tested, explaining former negative results. In addition to its adhesion-mediating properties, laminin-10/11 preparations also showed a mitogenic activity for human hematopoietic progenitor cells. Taken together, these data suggest that laminin in the bone marrow plays a hitherto unexpected important function in the development of hematopoietic progenitor cells.
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45
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Abstract
AbstractLaminins are a family of disulfide-linked heterotrimeric proteins consisting of 3 different subunits termed α, β, and γ chains. Combinations of 11 characterized laminin subunits (α1-α5, β1-β3, and γ1-γ3) generate at least 12 laminin isoforms, which can serve different functions. Although expression of laminin in the hematopoietic microenvironment has been known for many years, the nature of the laminin isoforms present in the human bone marrow is poorly characterized. The present study attempts to clarify this issue. Reverse transcriptase–polymerase chain reaction analysis of human bone marrow stromal cells suggested the expression of many laminin isoforms in the marrow. Northern blot and immunoblot analysis, however, showed that laminin-8/9 and laminin-10/11 are the most abundant laminin isoforms synthesized by human bone marrow stromal cells. Other isoforms, if present, certainly play a minor role in the hematopoietic microenvironment. Functionally, laminin-10/11 preparations showed strong adhesive interactions with human CD34+ cell lines. Antibodies against the β1 integrin subunit inhibited these interactions. Other laminin isoforms, especially laminin-1 and laminin-2/4, showed only weak or no adhesive interactions with the hematopoietic cell lines tested, explaining former negative results. In addition to its adhesion-mediating properties, laminin-10/11 preparations also showed a mitogenic activity for human hematopoietic progenitor cells. Taken together, these data suggest that laminin in the bone marrow plays a hitherto unexpected important function in the development of hematopoietic progenitor cells.
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46
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Fleischmajer R, Kuroda K, Utani A, Douglas MacDonald E, Perlish JS, Arikawa-Hirasawa E, Sekiguchi K, Sanzen N, Timpl R, Yamada Y. Differential expression of laminin alpha chains during proliferative and differentiation stages in a model for skin morphogenesis. Matrix Biol 2000; 19:637-47. [PMID: 11102753 DOI: 10.1016/s0945-053x(00)00092-5] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The purpose of this study was to determine the mRNA and protein expression of laminin alpha chains at various stages of in vitro skin morphogenesis. Fibroblasts in mono-cultures express low levels of the mRNA of laminin alpha1,alpha2, alpha3 and alpha4 chains. When co-cultured with keratinocytes for 28 days, they expressed the mRNA for all these chains. Keratinocytes in monolayer expressed the laminin alpha3 chain mRNA and very low levels of the mRNA of the alpha1 and alpha2 chains, although, when recombined with fibroblasts they also expressed laminin alpha1and alpha2 mRNA, but not the laminin alpha4 mRNA. Immunocytochemistry of cells in co-culture showed that laminin alpha1, alpha3 and alpha5 chains were expressed in the epidermis, while the laminin alpha2, beta1, and gamma1 chains were noted in the dermis and at the epidermo-dermal interface. The laminin alpha1chain was first expressed during the proliferative stage (14-21 days) and the laminin alpha2 and alpha5 chains appeared later, during the differentiation stage (28-42 days). The above results suggest that epithelial-mesenchymal interactions are involved in the expression of laminin alpha chain mRNA during in vitro skin morphogenesis. In addition, there is distinct temporal and spatial expression of these chains during proliferative and differentiation stages, possibly reflecting different functions.
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Affiliation(s)
- R Fleischmajer
- Department of Dermatology, Mount Sinai School of Medicine, Department of Dermatology, Box 1047, New York, NY 10029, USA.
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Goldfinger LE, Jiang L, Hopkinson SB, Stack MS, Jones JC. Spatial regulation and activity modulation of plasmin by high affinity binding to the G domain of the alpha 3 subunit of laminin-5. J Biol Chem 2000; 275:34887-93. [PMID: 10956663 DOI: 10.1074/jbc.m006652200] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cells in complex tissues contact extracellular matrix that interacts with integrin receptors to influence gene expression, proliferation, apoptosis, adhesion, and motility. During development, tissue remodeling, and tumorigenesis, matrix components are modified by enzymatic digestion with subsequent effects on integrin binding and signaling. We are interested in understanding the mechanisms by which broad spectrum proteinases such as plasmin are targeted to their extracellular matrix protein substrates. We have utilized plasmin-mediated cleavage of the epithelial basement membrane glycoprotein laminin-5 as a model to evaluate molecular events that direct plasmin activity to specific structural domains. We report that plasminogen and tissue plasminogen activator (tPA) exhibit high affinity, specific binding to the G(1) subdomain of the N terminus of the laminin-5 alpha(3) subunit, with equilibrium dissociation constants of 50 nm for plasminogen and 80 nm for tPA. No high affinity binding to the G(2), G(3), and G(4) subdomains was observed. As a result of binding to the G(1) subdomain, the catalytic efficiency of tPA-catalyzed plasminogen activation is enhanced 32-fold, leading to increased matrix-associated plasmin that is positioned favorably for cleavage within the G(4) subdomain as we have reported previously (Goldfinger, L. E., Stack, M. S., and Jones, J. C. R. (1998) J. Cell Biol. 141, 255-265). Thus, physical constraints dictated by interaction of proteinase and matrix macromolecule control not only enzymatic activity but may regulate substrate targeting of proteinases.
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Affiliation(s)
- L E Goldfinger
- Departments of Cell and Molecular Biology and Obstetrics and Gynecology, Northwestern University Medical School, Chicago, Illinois 60611, USA
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48
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Lattanzi G, Muntoni F, Sabatelli P, Squarzoni S, Maraldi NM, Cenni V, Villanova M, Columbaro M, Merlini L, Marmiroli S. Unusual laminin alpha2 processing in myoblasts from a patient with a novel variant of congenital muscular dystrophy. Biochem Biophys Res Commun 2000; 277:639-42. [PMID: 11062006 DOI: 10.1006/bbrc.2000.3735] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We recently described a novel congenital muscular dystrophy (CMD) syndrome characterized by mental retardation, microcephaly, and partial merosin deficiency on muscle biopsy. Linkage analysis excluded involvement of the known CMD loci. We now report on a study performed on the differentiation of cultured myoblasts from one patient affected by this condition to evaluate the potential to form myotubes and merosin processing in these cells. The differentiation rate was comparable to controls and myotubes were stable in culture. Biochemical analysis showed the expected 80-kDa merosin subunit in myoblasts. However, a shifted 60-kDa protein was detected in myotubes. Matrix-metalloproteinases (MMPs) zymography showed increased gelatinolytic activity, and immunoblotting identified an increased amount of membrane-type 1 matrix-metalloproteinase in pathological myotube preparations. Our results show that these CMD-derived myotubes contain a low molecular weight merosin. They further suggest that an altered regulation of MMPs can be involved in basal lamina damage.
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Affiliation(s)
- G Lattanzi
- Institute of Normal and Pathological Cytomorphology, CNR, Bologna, Italy
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Abstract
The laminin protein family has diverse tissue expression patterns and is involved in the pathology of a number of organs, including skin, muscle, and nerve. In the skin, laminins 5 and 6 contribute to dermal-epidermal cohesion, and mutations in the constituent chains result in the blistering phenotype observed in patients with junctional epidermolysis bullosa (JEB). Allelic heterogeneity is observed in patients with JEB: mutations that results in premature stop codons produce a more severe phenotype than do missense mutations. Gene therapy approaches are currently being studied in the treatment of this disease. A blistering phenotype is also observed in patients with acquired cicatricial pemphigoid (CP). Autoantibodies targeted against laminins 5 and 6 destabilize epithelial adhesion and are pathogenic. In muscle cells, laminin alpha 2 is a component of the bridge that links the actin cytoskeleton to the extracellular matrix. In patients with laminin alpha 2 mutations, the bridge is disrupted and mature muscle cells apoptose. Congenital muscular dystrophy (CMD) results. The role of laminin in diseases of the nervous system is less well defined, but the extracellular protein has been shown to serve an important role in peripheral nerve regeneration. The adhesive molecule influences neurite outgrowth, neural differentiation, and synapse formation. The broad spatial distribution of laminin gene products suggests that laminin may be involved in a number of diseases for which pathogenic mechanisms are still being unraveled.
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Affiliation(s)
- K A McGowan
- Department of Genetics, M-344, School of Medicine, Stanford University, Stanford, California 94305, USA
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Abstract
The laminins form a large family of modular proteins found in basement membranes, but also elsewhere. They function as structural components and are essential for morphogenesis, but in addition interact with cell surface receptors such as integrins and alpha-dystroglycan. By virtue of their receptor interactions, they initiate intracellular signalling events that regulate cellular organization and differentiation. The many interactions of laminins are mediated by binding sites, often contributed by single domains, which may differ between different forms of laminin. In the present article, we describe how the diversity of laminins and the genetic regulation of the expression of different laminin forms lead to the formation of extracellular matrices with variable laminin composition and thereby different biological properties.
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Affiliation(s)
- P Tunggal
- Institute for Biochemistry, Medical Faculty, University of Cologne, D-50931 Cologne, Germany
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