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Maiti G, Ashworth S, Choi T, Chakravarti S. Molecular cues for immune cells from small leucine-rich repeat proteoglycans in their extracellular matrix-associated and free forms. Matrix Biol 2023; 123:48-58. [PMID: 37793508 PMCID: PMC10841460 DOI: 10.1016/j.matbio.2023.10.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 09/14/2023] [Accepted: 10/01/2023] [Indexed: 10/06/2023]
Abstract
In this review we highlight emerging immune regulatory functions of lumican, keratocan, fibromodulin, biglycan and decorin, which are members of the small leucine-rich proteoglycans (SLRP) of the extracellular matrix (ECM). These SLRPs have been studied extensively as collagen-fibril regulatory structural components of the skin, cornea, bone and cartilage in homeostasis. However, SLRPs released from a remodeling ECM, or synthesized by activated fibroblasts and immune cells contribute to an ECM-free pool in tissues and circulation, that may have a significant, but poorly understood foot print in inflammation and disease. Their molecular interactions and the signaling networks they influence also require investigations. Here we present studies on the leucine-rich repeat (LRR) motifs of SLRP core proteins, their evolutionary and functional relationships with other LRR pathogen recognition receptors, such as the toll-like receptors (TLRs) to bring some molecular clarity in the immune regulatory functions of SLRPs. We discuss molecular interactions of fragments and intact SLRPs, and how some of these interactions are likely modulated by glycosaminoglycan side chains. We integrate findings on molecular interactions of these SLRPs together with what is known about their presence in circulation and lymph nodes (LN), which are important sites of immune cell regulation. Recent bulk and single cell RNA sequencing studies have identified subsets of stromal reticular cells that express these SLRPs within LNs. An understanding of the cellular source, molecular interactions and signaling consequences will lead to a fundamental understanding of how SLRPs modulate immune responses, and to therapeutic tools based on these SLRPs in the future.
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Affiliation(s)
- George Maiti
- Department of Ophthalmology, NYU Grossman School of Medicine, New York, NY, United States
| | - Sean Ashworth
- Department of Ophthalmology, NYU Grossman School of Medicine, New York, NY, United States
| | - Tansol Choi
- Department of Ophthalmology, NYU Grossman School of Medicine, New York, NY, United States
| | - Shukti Chakravarti
- Department of Ophthalmology, NYU Grossman School of Medicine, New York, NY, United States; Department of Pathology, NYU Grossman School of Medicine, New York, NY, United States.
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2
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Gollmann-Tepeköylü C, Graber M, Hirsch J, Mair S, Naschberger A, Pölzl L, Nägele F, Kirchmair E, Degenhart G, Demetz E, Hilbe R, Chen HY, Engert JC, Böhm A, Franz N, Lobenwein D, Lener D, Fuchs C, Weihs A, Töchterle S, Vogel GF, Schweiger V, Eder J, Pietschmann P, Seifert M, Kronenberg F, Coassin S, Blumer M, Hackl H, Meyer D, Feuchtner G, Kirchmair R, Troppmair J, Krane M, Weiss G, Tsimikas S, Thanassoulis G, Grimm M, Rupp B, Huber LA, Zhang SY, Casanova JL, Tancevski I, Holfeld J. Toll-Like Receptor 3 Mediates Aortic Stenosis Through a Conserved Mechanism of Calcification. Circulation 2023; 147:1518-1533. [PMID: 37013819 PMCID: PMC10192061 DOI: 10.1161/circulationaha.122.063481] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Accepted: 03/08/2023] [Indexed: 04/05/2023]
Abstract
BACKGROUND Calcific aortic valve disease (CAVD) is characterized by a phenotypic switch of valvular interstitial cells to bone-forming cells. Toll-like receptors (TLRs) are evolutionarily conserved pattern recognition receptors at the interface between innate immunity and tissue repair. Type I interferons (IFNs) are not only crucial for an adequate antiviral response but also implicated in bone formation. We hypothesized that the accumulation of endogenous TLR3 ligands in the valvular leaflets may promote the generation of osteoblast-like cells through enhanced type I IFN signaling. METHODS Human valvular interstitial cells isolated from aortic valves were challenged with mechanical strain or synthetic TLR3 agonists and analyzed for bone formation, gene expression profiles, and IFN signaling pathways. Different inhibitors were used to delineate the engaged signaling pathways. Moreover, we screened a variety of potential lipids and proteoglycans known to accumulate in CAVD lesions as potential TLR3 ligands. Ligand-receptor interactions were characterized by in silico modeling and verified through immunoprecipitation experiments. Biglycan (Bgn), Tlr3, and IFN-α/β receptor alpha chain (Ifnar1)-deficient mice and a specific zebrafish model were used to study the implication of the biglycan (BGN)-TLR3-IFN axis in both CAVD and bone formation in vivo. Two large-scale cohorts (GERA [Genetic Epidemiology Research on Adult Health and Aging], n=55 192 with 3469 aortic stenosis cases; UK Biobank, n=257 231 with 2213 aortic stenosis cases) were examined for genetic variation at genes implicated in BGN-TLR3-IFN signaling associating with CAVD in humans. RESULTS Here, we identify TLR3 as a central molecular regulator of calcification in valvular interstitial cells and unravel BGN as a new endogenous agonist of TLR3. Posttranslational BGN maturation by xylosyltransferase 1 (XYLT1) is required for TLR3 activation. Moreover, BGN induces the transdifferentiation of valvular interstitial cells into bone-forming osteoblasts through the TLR3-dependent induction of type I IFNs. It is intriguing that Bgn-/-, Tlr3-/-, and Ifnar1-/- mice are protected against CAVD and display impaired bone formation. Meta-analysis of 2 large-scale cohorts with >300 000 individuals reveals that genetic variation at loci relevant to the XYLT1-BGN-TLR3-interferon-α/β receptor alpha chain (IFNAR) 1 pathway is associated with CAVD in humans. CONCLUSIONS This study identifies the BGN-TLR3-IFNAR1 axis as an evolutionarily conserved pathway governing calcification of the aortic valve and reveals a potential therapeutic target to prevent CAVD.
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Affiliation(s)
| | - Michael Graber
- Department of Cardiac Surgery, Medical University of Innsbruck, Innsbruck, Austria
| | - Jakob Hirsch
- Department of Cardiac Surgery, Medical University of Innsbruck, Innsbruck, Austria
| | - Sophia Mair
- Department of Cardiac Surgery, Medical University of Innsbruck, Innsbruck, Austria
| | - Andreas Naschberger
- Institute of Genetic Epidemiology, Department of Genetics and Pharmacology, Medical University of Innsbruck, Innsbruck, Austria
- Division of Biological and Environmental Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955, Saudi Arabia
| | - Leo Pölzl
- Department of Cardiac Surgery, Medical University of Innsbruck, Innsbruck, Austria
| | - Felix Nägele
- Department of Cardiac Surgery, Medical University of Innsbruck, Innsbruck, Austria
| | - Elke Kirchmair
- Department of Cardiac Surgery, Medical University of Innsbruck, Innsbruck, Austria
| | - Gerald Degenhart
- Department of Radiology, Core Facility for Micro-CT, Medical University of Innsbruck, Innsbruck, Austria
| | - Egon Demetz
- Department of Internal Medicine III, Medical University of Innsbruck, Innsbruck, Austria
| | - Richard Hilbe
- Department of Internal Medicine III, Medical University of Innsbruck, Innsbruck, Austria
| | - Hao-Yu Chen
- Preventive and Genomic Cardiology, McGill University Health Centre Research Institute, Montreal, QC, Canada
| | - James C. Engert
- Preventive and Genomic Cardiology, McGill University Health Centre Research Institute, Montreal, QC, Canada
| | - Anna Böhm
- Department of Internal Medicine III, Medical University of Innsbruck, Innsbruck, Austria
| | - Nadja Franz
- Department of Cardiac Surgery, Medical University of Innsbruck, Innsbruck, Austria
| | - Daniela Lobenwein
- Department of Cardiac Surgery, Medical University of Innsbruck, Innsbruck, Austria
| | - Daniela Lener
- Department of Internal Medicine III, Medical University of Innsbruck, Innsbruck, Austria
| | - Christiane Fuchs
- Department Life Science Engineering, University of Applied Sciences Technikum Wien, Vienna, Austria
| | - Anna Weihs
- Department Life Science Engineering, University of Applied Sciences Technikum Wien, Vienna, Austria
| | - Sonja Töchterle
- Institute of Molecular Biology/CMBI, University of Innsbruck, Innsbruck, Austria
| | - Georg F. Vogel
- Department of Pediatrics/Institute of Cell biology, Medical University of Innsbruck, Innsbruck, Austria
| | - Victor Schweiger
- Department of Cardiac Surgery, Medical University of Innsbruck, Innsbruck, Austria
| | - Jonas Eder
- Department of Cardiac Surgery, Medical University of Innsbruck, Innsbruck, Austria
| | - Peter Pietschmann
- Division of Cellular and Molecular Pathophysiology, Department of Pathophysiology and Allergy Research, Center for Pathophysiology, Infectiology and Immunology, Medical University of Vienna, Vienna, Austria
| | - Markus Seifert
- Department of Internal Medicine III, Medical University of Innsbruck, Innsbruck, Austria
| | - Florian Kronenberg
- Institute of Genetic Epidemiology, Department of Genetics and Pharmacology, Medical University of Innsbruck, Innsbruck, Austria
| | - Stefan Coassin
- Institute of Genetic Epidemiology, Department of Genetics and Pharmacology, Medical University of Innsbruck, Innsbruck, Austria
| | - Michael Blumer
- Institute of Clinical and Functional Anatomy, Innsbruck Medical University, Innsbruck, Austria
| | - Hubert Hackl
- Institute of Bioinformatics, Medical University of Innsbruck, Innsbruck, Austria
| | - Dirk Meyer
- Institute of Molecular Biology/CMBI, University of Innsbruck, Innsbruck, Austria
| | - Gudrun Feuchtner
- Department of Radiology, Core Facility for Micro-CT, Medical University of Innsbruck, Innsbruck, Austria
| | - Rudolf Kirchmair
- Department of Internal Medicine III, Medical University of Innsbruck, Innsbruck, Austria
| | - Jakob Troppmair
- Daniel Swarovski Research Laboratory, Department of Visceral, Transplant and Thoracic Surgery, University of Innsbruck, Innsbruck, Innsbruck, Austria
| | - Markus Krane
- Department of Cardiovascular Surgery, German Heart Center Munich at the Technical University Munich, Munich, Germany
| | - Günther Weiss
- Department of Internal Medicine III, Medical University of Innsbruck, Innsbruck, Austria
| | - Sotirios Tsimikas
- Division of Cardiovascular Diseases, University of California, San Diego, La Jolla, USA
| | - George Thanassoulis
- Preventive and Genomic Cardiology, McGill University Health Centre Research Institute, Montreal, QC, Canada
| | - Michael Grimm
- Department of Cardiac Surgery, Medical University of Innsbruck, Innsbruck, Austria
| | - Bernhard Rupp
- Institute of Genetic Epidemiology, Department of Genetics and Pharmacology, Medical University of Innsbruck, Innsbruck, Austria
| | - Lukas A. Huber
- Institute of Cell Biology, Medical University of Innsbruck, Innsbruck, Austria
- Austrian Drug Screening Institute, ADSI, Innsbruck, Austria
| | - Shen-Ying Zhang
- St. Giles Laboratory of Human Genetics of Infectious Diseases, Rockefeller Branch, The Rockefeller University, New York, NY, USA
- Laboratory of Human Genetics of Infectious Diseases, Necker Branch, INSERM U1163, Necker Hospital for Sick Children, Paris, France
- University of Paris, Imagine Institute, Paris, France
| | - Jean-Laurent Casanova
- St. Giles Laboratory of Human Genetics of Infectious Diseases, Rockefeller Branch, The Rockefeller University, New York, NY, USA
- Laboratory of Human Genetics of Infectious Diseases, Necker Branch, INSERM U1163, Necker Hospital for Sick Children, Paris, France
- University of Paris, Imagine Institute, Paris, France
- Howard Hughes Medical Institute, New York, NY, USA
| | - Ivan Tancevski
- Department of Internal Medicine III, Medical University of Innsbruck, Innsbruck, Austria
| | - Johannes Holfeld
- Department of Cardiac Surgery, Medical University of Innsbruck, Innsbruck, Austria
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3
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Rivet R, Rao RM, Nizet P, Belloy N, Huber L, Dauchez M, Ramont L, Baud S, Brézillon S. Differential MMP-14 targeting by biglycan, decorin, fibromodulin, and lumican unraveled by in silico approach. Am J Physiol Cell Physiol 2023; 324:C353-C365. [PMID: 36534501 DOI: 10.1152/ajpcell.00429.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Small leucine-rich proteoglycans (SLRPs) are major regulators of extracellular matrix assembly and cell signaling. Lumican, a member of the SLRPs family, and its derived peptides were shown to possess antitumor activity by interacting directly with the catalytic domain of MMP-14 leading to the inhibition of its activity. The aim of the present report was to characterize by in silico three-dimensional (3D) modeling the structure and the dynamics of four SLRPs including their core protein and their specific polysaccharide chains to assess their capacity to bind to MMP-14 and to regulate its activity. Molecular docking experiments were performed to identify the specific amino acids of MMP-14 interacting with each of the four SLRPs. The inhibition of each SLRP (100 nM) on MMP-14 activity was measured and the constants of inhibition (Ki) were evaluated. The impact of the number of glycan chains, structures, and dynamics of lumican on the interaction with MMP-14 was assessed by molecular dynamics simulations. Molecular docking analysis showed that all SLRPs bind to MMP-14 through their concave face, but in different regions of the catalytic domain of MMP-14. Each SLRPs inhibited significantly the MMP-14 activity. Finally, molecular dynamics showed the role of glycan chains in interaction with MMP-14 and shielding effect of SLRPs. Altogether, the results demonstrated that each SLRP exhibited inhibition of MMP-14 activity. However, the differential targeting of MMP-14 by the SLRPs was shown to be related not only to the core protein conformation but also to the glycan chain structures and dynamics.
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Affiliation(s)
- Romain Rivet
- CNRS UMR 7369, Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne, Reims, France
| | - Rajas Mallenahalli Rao
- CNRS UMR 7369, Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne, Reims, France.,P3M, Multi-Scale-Molecular Modeling Platform, Université de Reims Champagne Ardenne, Reims, France
| | - Pierre Nizet
- CNRS UMR 7369, Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne, Reims, France
| | - Nicolas Belloy
- CNRS UMR 7369, Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne, Reims, France.,P3M, Multi-Scale-Molecular Modeling Platform, Université de Reims Champagne Ardenne, Reims, France
| | - Louise Huber
- CNRS UMR 7369, Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne, Reims, France
| | - Manuel Dauchez
- CNRS UMR 7369, Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne, Reims, France.,P3M, Multi-Scale-Molecular Modeling Platform, Université de Reims Champagne Ardenne, Reims, France
| | - Laurent Ramont
- CNRS UMR 7369, Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne, Reims, France.,CHU Reims, Service Biochimie Pharmacologie-Toxicologie, Reims, France
| | - Stéphanie Baud
- CNRS UMR 7369, Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne, Reims, France.,P3M, Multi-Scale-Molecular Modeling Platform, Université de Reims Champagne Ardenne, Reims, France
| | - Stéphane Brézillon
- CNRS UMR 7369, Matrice Extracellulaire et Dynamique Cellulaire (MEDyC), Université de Reims Champagne Ardenne, Reims, France
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4
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Giatagana EM, Berdiaki A, Gaardløs M, Tsatsakis AM, Samsonov SA, Nikitovic D. Rapamycin-induced autophagy in osteosarcoma cells is mediated via the biglycan/Wnt/β-catenin signaling axis. Am J Physiol Cell Physiol 2022; 323:C1740-C1756. [PMID: 36280393 DOI: 10.1152/ajpcell.00368.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Biglycan is a class I secreted small leucine-rich proteoglycan (SLRP), which regulates signaling pathways connected to bone pathologies. Autophagy is a vital catabolic process with a dual role in cancer progression. Here, we show that biglycan inhibits autophagy in two osteosarcoma cell lines (P ≤ 0.001), while rapamycin-induced autophagy decreases biglycan expression in MG63 osteosarcoma cells and abrogates the biglycan-induced cell growth increase (P ≤ 0.001). Rapamycin also inhibits β-catenin translocation to the nucleus, inhibiting the Wnt pathway (P ≤ 0.001) and reducing biglycan's colocalization with the Wnt coreceptor LRP6 (P ≤ 0.05). Furthermore, biglycan exhibits protective effects against the chemotherapeutic drug doxorubicin in MG63 OS cells through an autophagy-dependent manner (P ≤ 0.05). Cotreatment of these cells with rapamycin and doxorubicin enhances cells response to doxorubicin by decreasing biglycan (P ≤ 0.001) and β-catenin (P ≤ 0.05) expression. Biglycan deficiency leads to increased caspase-3 activation (P ≤ 0.05), suggesting increased apoptosis of biglycan-deficient cells treated with doxorubicin. Computational models of LRP6 and biglycan complexes suggest that biglycan changes the receptor's ability to interact with other signaling molecules by affecting the interdomain bending angles in the receptor structure. Biglycan binding to LRP6 activates the Wnt pathway and β-catenin nuclear translocation by disrupting β-catenin degradation complex (P ≤ 0.01 and P ≤ 0.05). Interestingly, this mechanism is not followed in moderately differentiated, biglycan-nonexpressing U-2OS OS cells. To sum up, biglycan exhibits protective effects against the doxorubicin in MG63 OS cells by activating the Wnt signaling pathway and inhibiting autophagy.
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Affiliation(s)
- Eirini-Maria Giatagana
- Laboratory of Histology-Embryology, Medical School, University of Crete, Heraklion Greece
| | - Aikaterini Berdiaki
- Laboratory of Histology-Embryology, Medical School, University of Crete, Heraklion Greece
| | - Margrethe Gaardløs
- Department of Theoretical Chemistry, Faculty of Chemistry, University of Gdańsk, Gdańsk, Poland
| | - Aristidis M Tsatsakis
- Laboratory of Toxicology, School of Medicine, University of Crete, Heraklion, Greece
| | - Sergey A Samsonov
- Department of Theoretical Chemistry, Faculty of Chemistry, University of Gdańsk, Gdańsk, Poland
| | - Dragana Nikitovic
- Laboratory of Histology-Embryology, Medical School, University of Crete, Heraklion Greece
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5
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Meester JAN, De Kinderen P, Verstraeten A, Loeys BL. The role of biglycan in the healthy and thoracic aneurysmal aorta. Am J Physiol Cell Physiol 2022; 322:C1214-C1222. [PMID: 35476501 DOI: 10.1152/ajpcell.00036.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The class I small leucine-rich proteoglycan biglycan is a crucial structural extracellular matrix component that interacts with a wide range of extracellular matrix molecules. In addition, biglycan is involved in sequestering growth factors such as TGF-β and BMPs and thereby regulating pathway activity. Biglycan consists of a 42-kDa core protein linked to two glycosaminoglycan side chains and both are involved in protein interactions. Biglycan is encoded by the BGN gene located on the X-chromosome and is expressed in various tissues, including vascular tissue, skin, brain, kidney lung, the immune system and the musculoskeletal system. Although an increasing amount of data on the biological function of biglycan in the vasculature has been produced, its role in thoracic aortic aneurysms is still not fully elucidated. This review focusses on the role of biglycan in the healthy thoracic aorta and the development of thoracic aortic aneurysm and dissections in both mice and humans.
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Affiliation(s)
- Josephina A N Meester
- Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium
| | - Pauline De Kinderen
- Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium
| | - Aline Verstraeten
- Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium
| | - Bart L Loeys
- Center of Medical Genetics, University of Antwerp and Antwerp University Hospital, Antwerp, Belgium.,Department of Clinical Genetics, Radboud University Medical Center, Nijmegen, The Netherlands
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6
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Huang C, Sharma A, Thakur R, Rai D, Katiki M, Germano JDF, Song Y, Singh S, Sin J, Sengstock D, Andres AM, Murali R, Mentzer RM, Gottlieb RA, Piplani H. Asporin, an extracellular matrix protein, is a beneficial regulator of cardiac remodeling. Matrix Biol 2022; 110:40-59. [DOI: 10.1016/j.matbio.2022.04.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Revised: 03/29/2022] [Accepted: 04/19/2022] [Indexed: 01/15/2023]
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7
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Biglycan Interacts with Type I Insulin-like Receptor (IGF-IR) Signaling Pathway to Regulate Osteosarcoma Cell Growth and Response to Chemotherapy. Cancers (Basel) 2022; 14:cancers14051196. [PMID: 35267503 PMCID: PMC8909324 DOI: 10.3390/cancers14051196] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Revised: 02/21/2022] [Accepted: 02/22/2022] [Indexed: 02/01/2023] Open
Abstract
Simple Summary Osteosarcoma (OS) is an aggressive, primary bone cancer. OS cells produce altered osteoid whose components participate in signaling correlated to the development of this cancer. Biglycan (BGN), a proteoglycan, is correlated to aggressive OS type and resistance to chemotherapy. A constitutive signaling of insulin-like growth factor receptor I (IGF-IR) signaling in sarcoma progression was established. We showed that biglycan binds IGF-IR resulting in prolonged IGF-IR activation, nuclear translocation, and growth response of the poorly-differentiated MG63 cells correlated to increased aggressiveness markers expression and enhanced chemoresistance. This mechanism is not valid in moderately and well-differentiated, biglycan non-expressing U-2OS and Saos-2 OS cells. Abstract Osteosarcoma (OS) is a mesenchymally derived, aggressive bone cancer. OS cells produce an aberrant nonmineralized or partly mineralized extracellular matrix (ECM) whose components participate in signaling pathways connected to specific pathogenic phenotypes of this bone cancer. The expression of biglycan (BGN), a secreted small leucine-rich proteoglycan (SLRP), is correlated to aggressive OS phenotype and resistance to chemotherapy. A constitutive signaling of IGF-IR signaling input in sarcoma progression has been established. Here, we show that biglycan activates the IGF-IR signaling pathway to promote MG63 biglycan-secreting OS cell growth by forming a complex with the receptor. Computational models of IGF-IR and biglycan docking suggest that biglycan binds IGF-IR dimer via its concave surface. Our binding free energy calculations indicate the formation of a stable complex. Biglycan binding results in prolonged IGF-IR activation leading to protracted IGF-IR-dependent cell growth response of the poorly-differentiated MG63 cells. Moreover, biglycan facilitates the internalization (p ≤ 0.01, p ≤ 0.001) and sumoylation-enhanced nuclear translocation of IGF-IR (p ≤ 0.05) and its DNA binding in MG63 cells (p ≤ 0.001). The tyrosine kinase activity of the receptor mediates this mechanism. Furthermore, biglycan downregulates the expression of the tumor-suppressor gene, PTEN (p ≤ 0.01), and increases the expression of endothelial–mesenchymal transition (EMT) and aggressiveness markers vimentin (p ≤ 0.01) and fibronectin (p ≤ 0.01) in MG63 cells. Interestingly, this mechanism is not valid in moderately and well-differentiated, biglycan non-expressing U-2OS and Saos-2 OS cells. Furthermore, biglycan exhibits protective effects against the chemotherapeutic drug, doxorubicin, in MG63 OS cells (p ≤ 0.01). In conclusion, these data indicate a potential direct and adjunct therapeutical role of biglycan in osteosarcoma.
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8
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Appunni S, Rubens M, Ramamoorthy V, Anand V, Khandelwal M, Sharma A. Biglycan: an emerging small leucine-rich proteoglycan (SLRP) marker and its clinicopathological significance. Mol Cell Biochem 2021; 476:3935-3950. [PMID: 34181183 DOI: 10.1007/s11010-021-04216-z] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 06/23/2021] [Indexed: 12/22/2022]
Abstract
Extracellular matrix (ECM) plays an important role in the structural organization of tissue and delivery of external cues to the cell. Biglycan, a class I small leucine-rich proteoglycans (SLRP), is a key component of the ECM that participates in scaffolding the collagen fibrils and mediates cell signaling. Dysregulation of biglycan expression can result in wide range of clinical conditions such as metabolic disorder, inflammatory disorder, musculoskeletal defects and malignancies. In this review, we aim to update our current understanding regarding the link between altered expression of biglycan and different clinicopathological states. Biglycan interacts with toll like receptors (TLR)-2 and TLR-4 on the immune cells which initiates inflammation and aggravates inflammatory disorders. ECM unbound soluble biglycan acts as a DAMP (danger associated molecular pattern) resulting in sterile inflammation. Dysregulation of biglycan expression is also observed in inflammatory metabolic conditions such as atherosclerosis and obesity. In cancer, high-biglycan expression facilitates tumor growth, invasion and metastasis which is associated with poor clinical outcome. As a pivotal structural component of the ECM, biglycan strengthens the musculoskeletal system and its absence is associated with musculoskeletal defects. Thus, SLRP biglycan is a potential marker which is significantly altered in different clinicopathological states.
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Affiliation(s)
- Sandeep Appunni
- Department of Biochemistry, All India Institute of Medical Sciences, New Delhi, 110 029, India
- Government Medical College, Kozhikode, Kerala, India
| | | | | | | | - Madhuram Khandelwal
- Department of Biochemistry, All India Institute of Medical Sciences, New Delhi, 110 029, India
| | - Alpana Sharma
- Department of Biochemistry, All India Institute of Medical Sciences, New Delhi, 110 029, India.
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Agrawal A, Ding J, Agrawal B, Kwan PO, Tredget EE. Stimulation of toll-like receptor pathways by burn eschar tissue as a possible mechanism for hypertrophic scarring. Wound Repair Regen 2021; 29:810-819. [PMID: 34043867 DOI: 10.1111/wrr.12940] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 03/28/2021] [Accepted: 04/09/2021] [Indexed: 01/02/2023]
Abstract
Hypertrophic scars (HTS) are a common complication following burn injuries with prolonged inflammation. They do not respond well to current treatment options including mechanical, biomolecular and surgical therapies. Toll-like receptor (TLR) 2 and 4 respond to microbes and damaged endogenous ligands to trigger pro-inflammatory pathways, and they are expressed more in HTS fibroblasts compared to normal skin fibroblasts. TLR2 responds to microbial lipoteichoic acid (LTA) while TLR4 responds to microbial lipopolysaccharide (LPS) and endogenous ligands. We investigated the role of burn tissue and small leucine-rich proteoglycans (decorin and biglycan) in the stimulation of TLR2 and TLR4 pathways using cells stably transfected with TLR2 or TLR4 linked to a reporter system. Normal skin (n = 5) was collected post-abdominoplasty, and burn eschar samples (n = 18) were collected from 18 patients between 0 and 14 days post-burn. We found that burn tissue stimulates TLR2 activity significantly more than normal tissue and contains significantly higher levels of LTA. Burn tissue was a stronger stimulator of TLR4 than was normal skin. Burn tissue samples' stimulation of TLR4 and TLR2 correlated. The time post-burn (0-14 days) of wound tissue sampling correlated positively but moderately with TLR2 and TLR4 simulation. In comparison to the dose-dependent effects of natural decorin or biglycan on TLR4 activation, their denatured forms exhibited stronger or weaker stimulation, respectively. They were not potent stimulators of TLR2. TLR2 and TLR4 stimulation is not limited to bacteria in wounds and likely involves multiple endogenous damage-associated molecular patterns. Insight into mechanisms of HTS will facilitate the development of future targeted therapies to modify wound progression and provide benefits to patients suffering with HTS and other fibroproliferative disorders.
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Affiliation(s)
- Ambika Agrawal
- Division of Plastic Surgery, University of Alberta, Edmonton, Alberta, Canada.,Department of Surgery, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Jie Ding
- Division of Plastic Surgery, University of Alberta, Edmonton, Alberta, Canada.,Department of Surgery, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Babita Agrawal
- Department of Surgery, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Peter O Kwan
- Division of Plastic Surgery, University of Alberta, Edmonton, Alberta, Canada.,Department of Surgery, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
| | - Edward E Tredget
- Division of Plastic Surgery, University of Alberta, Edmonton, Alberta, Canada.,Department of Surgery, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, Alberta, Canada
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10
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Matsushima N, Miyashita H, Kretsinger RH. Sequence features, structure, ligand interaction, and diseases in small leucine rich repeat proteoglycans. J Cell Commun Signal 2021; 15:519-531. [PMID: 33860400 DOI: 10.1007/s12079-021-00616-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2021] [Accepted: 03/25/2021] [Indexed: 12/26/2022] Open
Abstract
Small leucine rich repeat proteoglycans (SLRPs) are a group of active components of the extracellular matrix in all tissues. SLRPs bind to collagens and regulate collagen fibril growth and fibril organization. SLRPs also interact with various cytokines and extracellular compounds, which lead to various biological functions such cell adhesion and signaling, proliferation, and differentiation. Mutations in SLRP genes are associated with human diseases. Now crystal structures of five SLRPs are available. We describe some features of amino acid sequence and structures of SLRPs. We also review ligand interactions and then discuss the interaction surfaces. Furthermore, we map mutations associated with human diseases and discuss possible effects on structures by the mutations.
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Affiliation(s)
- Norio Matsushima
- Division of Bioinformatics, Institute of Tandem Repeats, Noboribetsu, 059-0464, Japan.
- Center for Medical Education, Sapporo Medical University, Sapporo, 060-8556, Japan.
| | - Hiroki Miyashita
- Division of Bioinformatics, Institute of Tandem Repeats, Noboribetsu, 059-0464, Japan
- Hokubu Rinsho Co., Ltd, Sapporo, 060⎼0061, Japan
| | - Robert H Kretsinger
- Department of Biology, University of Virginia, Charlottesville, VA, 22904, USA
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11
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Insights into substrate specificity of proteases for screening efficient dehairing enzymes. Int J Biol Macromol 2021; 172:360-370. [PMID: 33460659 DOI: 10.1016/j.ijbiomac.2021.01.065] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Revised: 01/06/2021] [Accepted: 01/12/2021] [Indexed: 11/22/2022]
Abstract
Though numerous proteases have been isolated and screened for the dehairing purpose, their use in the leather industry is limited mainly due to high cost, the need for expertise, and control during unit operation and alterations in the quality of leather due to lack of the right kind of substrate specificity of the enzymes used. This paper deals with the comparative specificity and dehairing efficiency of proteases isolated from Bacillus cereus VITSP01 (PE2) and Brevibacterium luteolum VITSP02 (PE). PE2 and PE were found to be trypsin-like and elastase-like serine proteases respectively. The protease of VITSP02 degraded the proteoglycans efficiently in comparison to that of VITSP01. The results suggest that the possible targets of the studied proteases might be skin proteoglycans, including those cementing the hair root bulb. Hence, an in-depth study on the substrate specificity of the dehairing proteases would help in designing an improved screening method for isolating potent dehairing enzymes.
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12
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Momin N, Mehta NK, Bennett NR, Ma L, Palmeri JR, Chinn MM, Lutz EA, Kang B, Irvine DJ, Spranger S, Wittrup KD. Anchoring of intratumorally administered cytokines to collagen safely potentiates systemic cancer immunotherapy. Sci Transl Med 2020; 11:11/498/eaaw2614. [PMID: 31243150 DOI: 10.1126/scitranslmed.aaw2614] [Citation(s) in RCA: 124] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 03/29/2019] [Accepted: 06/04/2019] [Indexed: 12/23/2022]
Abstract
The clinical application of cytokine therapies for cancer treatment remains limited due to severe adverse reactions and insufficient therapeutic effects. Although cytokine localization by intratumoral administration could address both issues, the rapid escape of soluble cytokines from the tumor invariably subverts this effort. We find that intratumoral administration of a cytokine fused to the collagen-binding protein lumican prolongs local retention and markedly reduces systemic exposure. Combining local administration of lumican-cytokine fusions with systemic immunotherapies (tumor-targeting antibody, checkpoint blockade, cancer vaccine, or T cell therapy) improves efficacy without exacerbating toxicity in syngeneic tumor models and the BrafV600E /Ptenfl/fl genetically engineered melanoma model. Curative abscopal effects on noncytokine-injected tumors were also observed as a result of a protective and systemic CD8+ T cell response primed by local therapy. Cytokine collagen-anchoring constitutes a facile, tumor-agnostic strategy to safely potentiate otherwise marginally effective systemic immunotherapies.
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Affiliation(s)
- Noor Momin
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Naveen K Mehta
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Nitasha R Bennett
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Leyuan Ma
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.,Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
| | - Joseph R Palmeri
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.,Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Magnolia M Chinn
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Emi A Lutz
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Byong Kang
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Darrell J Irvine
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.,Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.,Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard University, Cambridge, MA 02139, USA.,Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Stefani Spranger
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.,Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - K Dane Wittrup
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA. .,Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.,Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
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13
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Xiao D, Lu Y, Zhu L, Liang T, Wang Z, Ren J, He R, Wang K. Anti-osteosarcoma property of decorin-modified titanium surface: A novel strategy to inhibit oncogenic potential of osteosarcoma cells. Biomed Pharmacother 2020; 125:110034. [PMID: 32187963 DOI: 10.1016/j.biopha.2020.110034] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Revised: 02/14/2020] [Accepted: 02/17/2020] [Indexed: 01/03/2023] Open
Abstract
Osteosarcoma is the most common bone sarcoma in adolescents. Decorin (DCN) has been proposed to be a new anti-osteosarcoma therapeutic strategy. Our previous study has loaded decorin on titanium (Ti) surface by polydopamine (DOPA) as an anchor to enhance osseointegration. In this study, we investigated the effect of decorin-coated Ti substrates (TI-DOPA-DCN) on the oncogenic potential of osteosarcoma cells SAOS-2. The substrates were placed in 24-well plates for cell culture. Cell viability was determined by Cell Counting Kit-8 (CCK8) assay. Apoptosis was evaluated by DAPI staining and Annexin V-FITC/PI double staining analysis. Cell cycle was analyzed by flow cytometry. Cell migration and invasion were evaluated by Transwell assay. For co-culture, the pre-osteogenic cells MEC3T3-E1 and osteosarcoma cells SAOS-2 were stained with cell membrane fluorescent dyes, and then mixed (1:1) for co-culture. The cells were observed under a fluorescence microscope at four time points of 24, 48, 72, and 96 h. The results showed that TI-DOPA-DCN substrate can selectively inhibit cell proliferation of osteosarcoma cells but not pre-osteoblasts. However, the cell cycle of SAOS-2 was not affected by TI-DOPA-DCN substrates. Both DAPI staining and Annexin V-FITC/PI double staining analysis revealed that TI-DOPA-DCN substrates induced apoptosis of osteosarcoma cells. Transwell assay showed that TI-DOPA-DCN substrates inhibited invasion and migration of osteosarcoma cells. Moreover, TI-DOPA-DCN substrates inhibited the growth of osteosarcoma cells but promoted that of pre-osteoblasts in the coculture system. Taken together, these findings suggested that decorin coating on Ti surface simultaneously inhibited the oncogenic potential of osteosarcoma cells but enhanced cell growth of pre-osteoblasts, which could be applied to surface modification of Ti orthopedic implant.
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Affiliation(s)
- Dahai Xiao
- Department of Orthopaedic Surgery, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, China
| | - Yunxiang Lu
- Department of Joint and Trauma Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Lei Zhu
- Department of Plastic Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Tangzhao Liang
- Department of Joint and Trauma Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Zhe Wang
- Department of Joint and Trauma Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Jianhua Ren
- Department of Joint and Trauma Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China
| | - Ronghan He
- Department of Joint and Trauma Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
| | - Kun Wang
- Department of Joint and Trauma Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, China.
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14
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Batkhishig D, Bilguun K, Enkhbayar P, Miyashita H, Kretsinger RH, Matsushima N. Super Secondary Structure Consisting of a Polyproline II Helix and a β-Turn in Leucine Rich Repeats in Bacterial Type III Secretion System Effectors. Protein J 2019; 37:223-236. [PMID: 29651716 PMCID: PMC5976695 DOI: 10.1007/s10930-018-9767-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Leucine rich repeats (LRRs) are present in over 100,000 proteins from viruses to eukaryotes. The LRRs are 20–30 residues long and occur in tandem. LRRs form parallel stacks of short β-strands and then assume a super helical arrangement called a solenoid structure. Individual LRRs are separated into highly conserved segment (HCS) with the consensus of LxxLxLxxNxL and variable segment (VS). Eight classes have been recognized. Bacterial LRRs are short and characterized by two prolines in the VS; the consensus is xxLPxLPxx with Nine residues (N-subtype) and xxLPxxLPxx with Ten residues (T-subtype). Bacterial LRRs are contained in type III secretion system effectors such as YopM, IpaH3/9.8, SspH1/2, and SlrP from bacteria. Some LRRs in decorin, fribromodulin, TLR8/9, and FLRT2/3 from vertebrate also contain the motifs. In order to understand structural features of bacterial LRRs, we performed both secondary structures assignments using four programs—DSSP-PPII, PROSS, SEGNO, and XTLSSTR—and HELFIT analyses (calculating helix axis, pitch, radius, residues per turn, and handedness), based on the atomic coordinates of their crystal structures. The N-subtype VS adopts a left handed polyproline II helix (PPII) with four, five or six residues and a type I β-turn at the C-terminal side. Thus, the N-subtype is characterized by a super secondary structure consisting of a PPII and a β-turn. In contrast, the T-subtype VS prefers two separate PPIIs with two or three and two residues. The HELFIT analysis indicates that the type I β-turn is a right handed helix. The HELFIT analysis determines three unit vectors of the helix axes of PPII (P), β-turn (B), and LRR domain (A). Three structural parameters using these three helix axes are suggested to characterize the super secondary structure and the LRR domain.
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Affiliation(s)
- Dashdavaa Batkhishig
- Laboratory of Bioinformatics and Systems Biology, Department of Information and Computer Science, School of Engineering and Applied Sciences, National University of Mongolia, Ulaanbaatar, 14201, Mongolia.,Department of Physics, School of Mathematics and Natural Sciences, Mongolian National University of Education, Ulaanbaatar, 210648, Mongolia
| | - Khurelbaatar Bilguun
- Laboratory of Bioinformatics and Systems Biology, Department of Information and Computer Science, School of Engineering and Applied Sciences, National University of Mongolia, Ulaanbaatar, 14201, Mongolia.,Institute of Physics and Technology, Mongolian Academy of Sciences, Enkhtaivan avenue 54B, Ulaanbaatar, 210651, Mongolia
| | - Purevjav Enkhbayar
- Laboratory of Bioinformatics and Systems Biology, Department of Information and Computer Science, School of Engineering and Applied Sciences, National University of Mongolia, Ulaanbaatar, 14201, Mongolia.
| | - Hiroki Miyashita
- Hokubu Rinsho Co., Ltd, Sapporo, 060-0061, Japan.,Institute of Tandem Repeats, Sapporo, 004-0882, Japan
| | | | - Norio Matsushima
- Laboratory of Bioinformatics and Systems Biology, Department of Information and Computer Science, School of Engineering and Applied Sciences, National University of Mongolia, Ulaanbaatar, 14201, Mongolia. .,Institute of Tandem Repeats, Sapporo, 004-0882, Japan. .,Sapporo Medical University, Sapporo, 060-8556, Japan.
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15
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Small leucine-rich proteoglycans and matrix metalloproteinase-14: Key partners? Matrix Biol 2019; 75-76:271-285. [DOI: 10.1016/j.matbio.2017.12.006] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 12/12/2017] [Accepted: 12/13/2017] [Indexed: 11/19/2022]
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16
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Costa RA, Martins RST, Capilla E, Anjos L, Power DM. Vertebrate SLRP family evolution and the subfunctionalization of osteoglycin gene duplicates in teleost fish. BMC Evol Biol 2018; 18:191. [PMID: 30545285 PMCID: PMC6293640 DOI: 10.1186/s12862-018-1310-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 11/27/2018] [Indexed: 02/07/2023] Open
Abstract
Background Osteoglycin (OGN, a.k.a. mimecan) belongs to cluster III of the small leucine-rich proteoglycans (SLRP) of the extracellular matrix (ECM). In vertebrates OGN is a characteristic ECM protein of bone. In the present study we explore the evolution of SLRP III and OGN in teleosts that have a skeleton adapted to an aquatic environment. Results The SLRP gene family has been conserved since the separation of chondrichthyes and osteichthyes. Few gene duplicates of the SLRP III family exist even in the teleosts that experienced a specific whole genome duplication. One exception is ogn for which duplicate copies were identified in fish genomes. The ogn promoter sequence and in vitro mesenchymal stem cell (MSC) cultures suggest the duplicate ogn genes acquired divergent functions. In gilthead sea bream (Sparus aurata) ogn1 was up-regulated during osteoblast and myocyte differentiation in vitro, while ogn2 was severely down-regulated during bone-derived MSCs differentiation into adipocytes in vitro. Conclusions Overall, the phylogenetic analysis indicates that the SLRP III family in vertebrates has been under conservative evolutionary pressure. The retention of the ogn gene duplicates in teleosts was linked with the acquisition of different functions. The acquisition by OGN of functions other than that of a bone ECM protein occurred early in the vertebrate lineage. Electronic supplementary material The online version of this article (10.1186/s12862-018-1310-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- R A Costa
- Comparative Endocrinology and Integrative Biology Group, Centre of Marine Sciences, University of Algarve, Campus of Gambelas, 8005-139, Faro, Portugal
| | - R S T Martins
- Comparative Endocrinology and Integrative Biology Group, Centre of Marine Sciences, University of Algarve, Campus of Gambelas, 8005-139, Faro, Portugal.
| | - E Capilla
- Department of Cell Biology, Physiology and Immunology, Faculty of Biology, University of Barcelona, 08028, Barcelona, Spain
| | - L Anjos
- Comparative Endocrinology and Integrative Biology Group, Centre of Marine Sciences, University of Algarve, Campus of Gambelas, 8005-139, Faro, Portugal
| | - D M Power
- Comparative Endocrinology and Integrative Biology Group, Centre of Marine Sciences, University of Algarve, Campus of Gambelas, 8005-139, Faro, Portugal.
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17
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Sujitha P, Kavitha S, Shakilanishi S, Babu NKC, Shanthi C. Enzymatic dehairing: A comprehensive review on the mechanistic aspects with emphasis on enzyme specificity. Int J Biol Macromol 2018; 118:168-179. [DOI: 10.1016/j.ijbiomac.2018.06.081] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 06/13/2018] [Accepted: 06/15/2018] [Indexed: 12/31/2022]
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18
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Karamanos NK, Piperigkou Z, Theocharis AD, Watanabe H, Franchi M, Baud S, Brézillon S, Götte M, Passi A, Vigetti D, Ricard-Blum S, Sanderson RD, Neill T, Iozzo RV. Proteoglycan Chemical Diversity Drives Multifunctional Cell Regulation and Therapeutics. Chem Rev 2018; 118:9152-9232. [DOI: 10.1021/acs.chemrev.8b00354] [Citation(s) in RCA: 193] [Impact Index Per Article: 32.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Nikos K. Karamanos
- Biochemistry, Biochemical Analysis & Matrix Pathobiology Research Group, Laboratory of Biochemistry, Department of Chemistry, University of Patras, Patras 26110, Greece
- Foundation for Research and Technology-Hellas (FORTH)/Institute of Chemical Engineering Sciences (ICE-HT), Patras 26110, Greece
| | - Zoi Piperigkou
- Biochemistry, Biochemical Analysis & Matrix Pathobiology Research Group, Laboratory of Biochemistry, Department of Chemistry, University of Patras, Patras 26110, Greece
- Foundation for Research and Technology-Hellas (FORTH)/Institute of Chemical Engineering Sciences (ICE-HT), Patras 26110, Greece
| | - Achilleas D. Theocharis
- Biochemistry, Biochemical Analysis & Matrix Pathobiology Research Group, Laboratory of Biochemistry, Department of Chemistry, University of Patras, Patras 26110, Greece
| | - Hideto Watanabe
- Institute for Molecular Science of Medicine, Aichi Medical University, Aichi 480-1195, Japan
| | - Marco Franchi
- Department for Life Quality Studies, University of Bologna, Rimini 47100, Italy
| | - Stéphanie Baud
- Université de Reims Champagne-Ardenne, Laboratoire SiRMa, CNRS UMR MEDyC 7369, Faculté de Médecine, 51 rue Cognacq Jay, Reims 51100, France
| | - Stéphane Brézillon
- Université de Reims Champagne-Ardenne, Laboratoire de Biochimie Médicale et Biologie Moléculaire, CNRS UMR MEDyC 7369, Faculté de Médecine, 51 rue Cognacq Jay, Reims 51100, France
| | - Martin Götte
- Department of Gynecology and Obstetrics, Münster University Hospital, Münster 48149, Germany
| | - Alberto Passi
- Department of Medicine and Surgery, University of Insubria, Varese 21100, Italy
| | - Davide Vigetti
- Department of Medicine and Surgery, University of Insubria, Varese 21100, Italy
| | - Sylvie Ricard-Blum
- University Claude Bernard Lyon 1, CNRS, UMR 5246, Institute of Molecular and Supramolecular Chemistry and Biochemistry, Villeurbanne 69622, France
| | - Ralph D. Sanderson
- Department of Pathology, Comprehensive Cancer Center, University of Alabama at Birmingham, Birmingham, Alabama 35294, United States
| | - Thomas Neill
- Department of Pathology, Anatomy and Cell Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania 10107, United States
| | - Renato V. Iozzo
- Department of Pathology, Anatomy and Cell Biology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania 10107, United States
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19
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Godoy‐Guzmán C, Nuñez C, Orihuela P, Campos A, Carriel V. Distribution of extracellular matrix molecules in human uterine tubes during the menstrual cycle: a histological and immunohistochemical analysis. J Anat 2018; 233:73-85. [PMID: 29663371 PMCID: PMC5987832 DOI: 10.1111/joa.12814] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/07/2018] [Indexed: 11/30/2022] Open
Abstract
The uterine tube (UT) is an important and complex organ of the women's reproductive system. In general, the anatomy and basic histology of this organ are well-known. However, the composition and function of the extracellular matrix (ECM) of the UT is still poorly understood. The ECM is a complex supramolecular material produced by cells which is commonly restricted to the basement membrane and interstitial spaces. ECM molecules play not only a structural role, they are also important for cell growth, survival and differentiation in all tissues. In this context, the aim of this study was to evaluate the deposition and distribution of type I and III collagens and proteoglycans (decorin, biglycan, fibromodulin and versican) in human UT during the follicular and luteal phases by using histochemical and immunohistochemical techniques. Our results showed a broad synthesis of collagens (I and III) in the stroma of the UT. The analysis by regions showed, in the mucosa, a specific distribution of versican and fibromodulin in the epithelial surface, whereas decorin and fibromodulin were observed in the lamina propria. Versican and decorin were found in the stroma of the muscular layer, whereas all studied proteoglycans were identified in the serosa. Curiously, biglycan was restricted to the wall of the blood vessels of the serosa and muscular layers. Furthermore, there was an immunoreaction for collagens, decorin, versican and fibromodulin in the UT peripheral nerves. The differential distribution of these ECM molecules in the different layers of the UT could be related to specific structural and/or biomechanical functions needed for the oviductal transport, successful fertilization and early embryogenesis. However, further molecular studies under physiological and pathological conditions are still needed to elucidate the specific role of each molecule in the human UT.
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Affiliation(s)
- Carlos Godoy‐Guzmán
- Department of HistologyTissue Engineering GroupFaculty of MedicineUniversity of GranadaSpain
- Doctoral Program in BiomedicineUniversity of GranadaGranadaSpain
- Centro de Investigaciones Biomédicas y AplicadasEscuela de MedicinaUniversidad de Santiago de Chile, (USACH)SantiagoChile
| | - Claudio Nuñez
- Servicio de Ginecología y ObstetriciaHospital San JoséSantiagoChile
| | - Pedro Orihuela
- Laboratorio de Inmunología de la ReproduccíonFacultad de Química y BiologíaUniversidad de Santiago de ChileSantiagoChile
- Centro para el Desarrollo en Nanociencia y Nanotecnologıa‐CEDENNASantiagoChile
| | - Antonio Campos
- Department of HistologyTissue Engineering GroupFaculty of MedicineUniversity of GranadaSpain
- Instituto de Investigación Biosanitaria Ibs.GRANADAEspaña
| | - Víctor Carriel
- Department of HistologyTissue Engineering GroupFaculty of MedicineUniversity of GranadaSpain
- Instituto de Investigación Biosanitaria Ibs.GRANADAEspaña
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20
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Identification of the effector domain of biglycan that facilitates BMP-2 osteogenic function. Sci Rep 2018; 8:7022. [PMID: 29728612 PMCID: PMC5935668 DOI: 10.1038/s41598-018-25279-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 04/09/2018] [Indexed: 01/22/2023] Open
Abstract
We have reported that recombinant biglycan (BGN) core protein accelerates bone formation in vivo by enhancing bone morphogenetic protein (BMP)-2 function. The purpose of the present study was to identify the specific domain (“effector”) within the BGN core protein that facilitates BMP-2 osteogenic function. Thus, we generated various recombinant and synthetic peptides corresponding to several domains of BGN, and tested their effects on BMP-2 functions in vitro. The results demonstrated that the leucine-rich repeats 2–3 domain (LRR2-3) of BGN significantly enhanced the BMP-2 induced Smad1/5/9 phosphorylation, osteogenic gene expression, and alkaline phosphatase activity in myogenic C2C12 cells. Furthermore, addition of LRR2-3 to osteoblastic MC3T3-E1 cells accelerated in vitro mineralization without compromising the quality of the mineral and matrix. These data indicate that LRR2-3 is, at least in part, responsible for BGN’s ability to enhance BMP-2 osteogenic function, and it could be useful for bone tissue regeneration.
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21
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Fallon JR, McNally EM. Non-Glycanated Biglycan and LTBP4: Leveraging the extracellular matrix for Duchenne Muscular Dystrophy therapeutics. Matrix Biol 2018; 68-69:616-627. [PMID: 29481844 DOI: 10.1016/j.matbio.2018.02.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2018] [Revised: 02/18/2018] [Accepted: 02/19/2018] [Indexed: 12/15/2022]
Abstract
The extracellular matrix (ECM) plays key roles in normal and diseased skeletal and cardiac muscle. In healthy muscle the ECM is essential for transmitting contractile force, maintaining myofiber integrity and orchestrating cellular signaling. Duchenne Muscular Dystrophy (DMD) is caused by loss of dystrophin, a cytosolic protein that anchors a transmembrane complex and serves as a vital link between the actin cytoskeleton and the basal lamina. Loss of dystrophin leads to membrane fragility and impaired signaling, resulting in myofiber death and cycles of inflammation and regeneration. Fibrosis is also a cardinal feature of DMD. In this review, we will focus on two cases where understanding the normal function and regulation of ECM in muscle has led to the discovery of candidate therapeutics for DMD. Biglycan is a small leucine rich repeat ECM protein present as two glycoforms in muscle that have dramatically different functions. One widely expressed form is biglycan proteoglycan (PG) that bears two chondroitin sulfate GAG chains (typically chondroitin sulfate) and two N-linked carbohydrates. The second glycoform, referred to as 'NG' (non-glycanated) biglycan, lacks the GAG side chains. NG, but not PG biglycan recruits utrophin, an autosomal paralog of dystrophin, and an NOS-containing signaling complex to the muscle cell membrane. Recombinant NG biglycan can be systemically delivered to dystrophic mice where it upregulates utrophin at the membrane and improves muscle health and function. An optimized version of NG biglycan, 'TVN-102', is under development as a candidate therapeutic for DMD. A second matrix-embedded protein being evaluated for therapeutic potential is latent TGFβ binding protein 4 (LTBP4). Identified in a genomic screen for modifiers of muscular dystrophy, LTBP4 binds both TGFβ and myostatin. Genetic studies identified the hinge region of LTBP4 as linked to TGFβ release and contributing to the "hyper-TGFβ" signaling state that promotes fibrosis in muscular dystrophy. This hinge region can be stabilized by antibodies directed towards this domain. Stabilizing the hinge region of LTBP4 is expected to reduce latent TGFβ release and thus reduce fibrosis.
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Affiliation(s)
- Justin R Fallon
- Dept. of Neuroscience, Brown University, Providence, RI 02912, United States.
| | - Elizabeth M McNally
- Center for Genetic Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, United States
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22
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Marqueti RC, Durigan JLQ, Oliveira AJS, Mekaro MS, Guzzoni V, Aro AA, Pimentel ER, Selistre-de-Araujo HS. Effects of aging and resistance training in rat tendon remodeling. FASEB J 2017; 32:353-368. [PMID: 28899880 DOI: 10.1096/fj.201700543r] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 08/28/2017] [Indexed: 12/21/2022]
Abstract
In elderly persons, weak tendons contribute to functional limitations, injuries, and disability, but resistance training can attenuate this age-related decline. We evaluated the effects of resistance training on the extracellular matrix (ECM) of the calcaneal tendon (CT) in young and old rats and its effect on tendon remodeling. Wistar rats aged 3 mo (young, n = 30) and 20 mo (old, n = 30) were divided into 4 groups: young sedentary, young trained, old sedentary (OS), and old trained (OT). The training sessions were conducted over a 12-wk period. Aging in sedentary rats showed down-regulation in key genes that regulated ECM remodeling. Moreover, the OS group showed a calcification focus in the distal region of the CT, with reduced blood vessel volume density. In contrast, resistance training was effective in up-regulating connective tissue growth factor, VEGF, and decorin gene expression in old rats. Resistance training also increased proteoglycan content in young and old rats in special small leucine-rich proteoglycans and blood vessels and prevented calcification in OT rats. These findings confirm that resistance training is a potential mechanism in the prevention of aging-related loss in ECM and that it attenuates the detrimental effects of aging in tendons, such as ruptures and tendinopathies.-Marqueti, R. C., Durigan, J. L. Q., Oliveira, A. J. S., Mekaro, M. S., Guzzoni, V., Aro, A. A., Pimentel, E. R., Selistre-de-Araujo, H. S. Effects of aging and resistance training in rat tendon remodeling.
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Affiliation(s)
- Rita C Marqueti
- University of Brasília (UnB), Brasília, Distrito Federal, Brazil;
| | - João L Q Durigan
- University of Brasília (UnB), Brasília, Distrito Federal, Brazil
| | | | | | - Vinicius Guzzoni
- Federal University of São Carlos (UFSCar), São Carlos, São Paulo, Brazil
| | - Andrea A Aro
- Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil
| | - Edson Rosa Pimentel
- Department of Structural and Functional Biology, Institute of Biology, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil.,Heminio Ometto University Center (UNIARARAS), Araras, São Paulo, Brazil
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Biglycan Inhibits Capsaicin-Induced Substance P Release by Cultured Dorsal Root Ganglion Neurons. Am J Phys Med Rehabil 2017; 95:656-62. [PMID: 26945213 DOI: 10.1097/phm.0000000000000460] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The purpose of this study was to examine the inhibitory effects of biglycan on substance P release from cultured sensory neurons in response to capsaicin. STUDY DESIGN In vitro study of cultured primary sensory neurons from the rabbit dorsal root ganglion (DRG). We interrogated the culture system function with capsaicin. Biglycan is an important structural component of the intervertebral disc that may regulate growth factors and inflammatory mediators. We tested the hypothesis that biglycan inhibits substance P release in response to capsaicin. RESULTS The DRG cultures were shown to contain both neurons and astrocytes by immunostaining using antibodies recognizing neuron and glial cell markers. Cultured DRG cells respond to capsaicin in a dose- and time-dependent manner (capsaicin dose ranges from 5 to 500 μmol/L; stimulation time ranges from 0 to 60 minutes). The neurons preincubated with biglycan released 27% less substance P compared with neurons without biglycan (n = 4, P = 0.036). CONCLUSION We have established a DRG cell culture system, which contains both sensory neurons and the supporting astrocytes. Biglycan, an inhibitor of substance P release by DRG cultures, may serve as an ingredient in intradiscal injectables to reduce back pain.
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Moffatt P, Geng Y, Lamplugh L, Nanci A, Roughley PJ. Absence of the dermatan sulfate chain of decorin does not affect mouse development. J Negat Results Biomed 2017; 16:7. [PMID: 28412940 PMCID: PMC5393030 DOI: 10.1186/s12952-017-0074-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 02/20/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In vitro studies suggest that the multiple functions of decorin are related to both its core protein and its dermatan sulfate chain. To determine the contribution of the dermatan sulfate chain to the functional properties of decorin in vivo, a mutant mouse whose decorin lacked a dermatan sulfate chain was generated. RESULTS Homozygous mice expressing only the decorin core protein developed and grew in a similar manner to wild type mice. In both embryonic and postnatal mice, all connective tissues studied, including cartilage, skin and cornea, appeared to be normal upon histological examination, and their collagen fibrils were of normal diameter and organization. In addition, abdominal skin wounds healed in an identical manner in the mutant and wild type mice. CONCLUSIONS The absence of a dermatan sulfate chain on decorin does not appear to overtly influence its functional properties in vivo.
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Affiliation(s)
- Pierre Moffatt
- Research Center, Shriners Hospitals for Children - Canada, 1003 Boulevard Décarie, Montréal, H4A 0A9, QC, Canada. .,Department of Human Genetics, Faculty of Medicine, McGill University, Montreal, QC, Canada.
| | - Yeqing Geng
- Research Center, Shriners Hospitals for Children - Canada, 1003 Boulevard Décarie, Montréal, H4A 0A9, QC, Canada
| | - Lisa Lamplugh
- Research Center, Shriners Hospitals for Children - Canada, 1003 Boulevard Décarie, Montréal, H4A 0A9, QC, Canada
| | - Antonio Nanci
- Laboratory for the Study of Calcified Tissues and Biomaterials, Department of Stomatology, Faculty of Dentistry, Université de Montréal, Montréal, QC, Canada
| | - Peter J Roughley
- Research Center, Shriners Hospitals for Children - Canada, 1003 Boulevard Décarie, Montréal, H4A 0A9, QC, Canada.,Department of Human Genetics, Faculty of Medicine, McGill University, Montreal, QC, Canada
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Paracuellos P, Kalamajski S, Bonna A, Bihan D, Farndale RW, Hohenester E. Structural and functional analysis of two small leucine-rich repeat proteoglycans, fibromodulin and chondroadherin. Matrix Biol 2017; 63:106-116. [PMID: 28215822 PMCID: PMC5618690 DOI: 10.1016/j.matbio.2017.02.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 02/09/2017] [Accepted: 02/09/2017] [Indexed: 02/07/2023]
Abstract
The small leucine-rich proteoglycans (SLRPs) are important regulators of extracellular matrix assembly and cell signalling. We have determined crystal structures at ~ 2.2 Å resolution of human fibromodulin and chondroadherin, two collagen-binding SLRPs. Their overall fold is similar to that of the prototypical SLRP, decorin, but unlike decorin neither fibromodulin nor chondroadherin forms a stable dimer. A previously identified binding site for integrin α2β1 maps to an α-helix in the C-terminal cap region of chondroadherin. Interrogation of the Collagen Toolkits revealed a unique binding site for chondroadherin in collagen II, and no binding to collagen III. A triple-helical peptide containing the sequence GAOGPSGFQGLOGPOGPO (O is hydroxyproline) forms a stable complex with chondroadherin in solution. In fibrillar collagen I and II, this sequence is aligned with the collagen cross-linking site KGHR, suggesting a role for chondroadherin in cross-linking. The crystal structures of fibromodulin and chondroadherin have been determined. Fibromodulin and chondroadherin are monomeric in solution. Chondroadherin binds to a unique site in type II collagen that contains the sequence GAOGPSGFQGLOGPOGPO (O, hydroxyproline). In collagen fibres, the chondroadherin binding site is adjacent to the cross-linking site, KGHR.
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Affiliation(s)
| | | | - Arkadiusz Bonna
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| | - Dominique Bihan
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| | - Richard W Farndale
- Department of Biochemistry, University of Cambridge, Cambridge, United Kingdom
| | - Erhard Hohenester
- Department of Life Sciences, Imperial College London, London, United Kingdom.
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Rämisch S, Pramhed A, Tillgren V, Aspberg A, Logan DT. Crystal structure of human chondroadherin: solving a difficult molecular-replacement problem usingde novomodels. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2017; 73:53-63. [DOI: 10.1107/s205979831601980x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 12/12/2016] [Indexed: 02/08/2023]
Abstract
Chondroadherin (CHAD) is a cartilage matrix protein that mediates the adhesion of isolated chondrocytes. Its protein core is composed of 11 leucine-rich repeats (LRR) flanked by cysteine-rich domains. CHAD makes important interactions with collagen as well as with cell-surface heparin sulfate proteoglycans and α2β1integrins. The integrin-binding site is located in a region of hitherto unknown structure at the C-terminal end of CHAD. Peptides based on the C-terminal human CHAD (hCHAD) sequence have shown therapeutic potential for treating osteoporosis. This article describes a still-unconventional structure solution by phasing withde novomodels, the first of a β-rich protein. Structure determination of hCHAD using traditional, though nonsystematic, molecular replacement was unsuccessful in the hands of the authors, possibly owing to a combination of low sequence identity to other LRR proteins, four copies in the asymmetric unit and weak translational pseudosymmetry. However, it was possible to solve the structure by generating a large number ofde novomodels for the central LRR domain usingRosettaand multiple parallel molecular-replacement attempts usingAMPLE. The hCHAD structure reveals an ordered C-terminal domain belonging to the LRRCT fold, with the integrin-binding motif (WLEAK) being part of a regular α-helix, and suggests ways in which experimental therapeutic peptides can be improved. The crystal structure itself and docking simulations further support that hCHAD dimers form in a similar manner to other matrix LRR proteins.
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Fuller E, Little CB, Melrose J. Interleukin-1α induces focal degradation of biglycan and tissue degeneration in an in-vitro ovine meniscal model. Exp Mol Pathol 2016; 101:214-220. [PMID: 27615609 DOI: 10.1016/j.yexmp.2016.09.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Revised: 09/05/2016] [Accepted: 09/07/2016] [Indexed: 10/21/2022]
Abstract
We have developed an ovine meniscal explant model where the focal degradative events leading to characteristic fragmentation patterns of biglycan in human OA of the knee and hip, and evident in animal models of knee OA and IVD degeneration are reproduced in culture. Lateral and medial menisci were dissected into outer, mid and inner zones and established in explant culture±IL-1 (10ng/ml). The biglycan species present in conditioned media samples and in GuHCl extracts of tissues were examined by Western blotting using two C-terminal antibodies PR-85 and EF-Bgn. Clear differences were evident in the biglycan species in each meniscal tissue zone with the medial outer meniscus having lower biglycan levels and major fragments of 20, 28, 33 and 36, 39kDa. Similar fragmentation was detected in articular cartilage samples, 42-45kDa core protein species were also detected. Biglycan fragmentation was not as extensive in the IL-1 stimulated meniscal cultures with 36, 39, 42 and 45kDa biglycan species evident. Thus the medial meniscus outer zone displayed the highest levels of biglycan processing in this model and correlated with a major zone of meniscal remodelling in OA in man. Significantly, enzymatic digests of meniscal tissues with MMP-13, ADAMTS-4 and ADAMTS-5 have also generated similar biglycan species in-vitro. Zymography confirmed that the medial outer zone was the region of maximal MMP activity. This model represents a convenient system to recapitulate matrix remodelling events driven by IL-1 in pathological cartilages and in animal models of joint degeneration.
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Affiliation(s)
- Emily Fuller
- Raymond Purves Bone and Joint Research Laboratory, Kolling Institute, Northern Sydney Local Health District, St. Leonards, NSW 2065, Australia
| | - Christopher B Little
- Raymond Purves Bone and Joint Research Laboratory, Kolling Institute, Northern Sydney Local Health District, St. Leonards, NSW 2065, Australia; Sydney Medical School, Northern, The University of Sydney, Royal North Shore Hospital, Australia
| | - James Melrose
- Raymond Purves Bone and Joint Research Laboratory, Kolling Institute, Northern Sydney Local Health District, St. Leonards, NSW 2065, Australia; Sydney Medical School, Northern, The University of Sydney, Royal North Shore Hospital, Australia; School of Biomedical Engineering, University of New South Wales, Kensington, NSW 2052, Australia.
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28
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Frikeche J, Maiti G, Chakravarti S. Small leucine-rich repeat proteoglycans in corneal inflammation and wound healing. Exp Eye Res 2016; 151:142-9. [PMID: 27569372 DOI: 10.1016/j.exer.2016.08.015] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 08/23/2016] [Accepted: 08/24/2016] [Indexed: 10/21/2022]
Abstract
The small leucine rich repeat proteoglycans are major components of the cornea. Lumican, keratocan, decorin, biglycan and osteoglycin are present throughout the adult corneal stroma, and fibromodulin in the peripheral limbal area. In the cornea literature these proteoglycan have been reviewed as structural, collagen fibril-regulating proteins of the cornea. However, these proteoglycans are members of the leucine-rich-repeat superfamily, and share structural similarities with pathogen recognition toll-like receptors. Emerging studies are showing that these have a range of interactions with cell surface receptors, chemokines, growth factors and pathogen associated molecular patterns and are able to regulate host immune response, inflammation and wound healing. This review discusses what is known about their innate immune-related role directly in the cornea, and studies outside the field that find interesting links with innate immune and wound healing responses that are likely to be relevant to the ocular surface. In addition, the review discusses phenotypes of mice with targeted deletion of proteoglycan genes and genetic variants associated with human pathologies.
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Affiliation(s)
- Jihane Frikeche
- Department of Medicine, Johns Hopkins School of Medicine, Baltimore, USA
| | - George Maiti
- Department of Medicine, Johns Hopkins School of Medicine, Baltimore, USA
| | - Shukti Chakravarti
- Department of Medicine, Johns Hopkins School of Medicine, Baltimore, USA; Department of Cell Biology, Johns Hopkins School of Medicine, Baltimore, USA; Department of Ophthalmology, Johns Hopkins School of Medicine, Baltimore, USA.
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29
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Liu Y, Wang X, Wang Z, Ju W, Wang D. Decorin inhibits the proliferation of HepG2 cells by elevating the expression of transforming growth factor-β receptor II. Exp Ther Med 2016; 12:2191-2195. [PMID: 27698710 DOI: 10.3892/etm.2016.3572] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Accepted: 04/19/2016] [Indexed: 12/28/2022] Open
Abstract
The aim of the present study was to investigate the effects of decorin (DCN) on the proliferation of human hepatoma HepG2 cells and the involvement of transforming growth factor-β (TGF-β) signaling pathway. A vector containing DCN was transfected into HepG2 cells with the use of Lipofectamine 2000. Cell proliferation was assessed with an MTT assay, and western blot analysis was used to detect the protein expression of TGF-β receptor I (TGF-βRI), phosphorylated TGF-βRI, p15 and TGF-βRII. In addition, small interfering RNA (siRNA) silencing was performed to knock down the target gene. The results indicated that, compared with the control group, cell proliferation was significantly decreased in HepG2 cells transfected with DCN. In addition, DCN transfection significantly increased the phosphorylation level of TGF-βRI in HepG2 cells. The expression of the downstream factor p15 was also significantly elevated in the DCN-transfected HepG2 cells. Furthermore, DCN transfection significantly elevated the expression level of TGF-βRII in HepG2 cells. By contrast, the silencing of TGF-βRII significantly decreased the phosphorylation of TGF-βRI in DCN-transfected HepG2 cells. In addition, TGF-βRII silencing abolished the effects of DCN on the proliferation of HepG2 cells. In conclusion, DCN elevated the expression level of TGF-βRII, increased the phosphorylation level of TGF-βRI, enhanced the expression of p15, and finally inhibited the proliferation of HepG2 cells. These findings may contribute to the understanding of the role of DCN in the pathogenesis of hepatic carcinoma and assist in the disease treatment.
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Affiliation(s)
- Yanfeng Liu
- Department of Human Anatomy, College of Basic Medical Sciences, Beihua University, Jilin, Jilin 132013, P.R. China
| | - Xuesong Wang
- Department of Human Anatomy, College of Basic Medical Sciences, Beihua University, Jilin, Jilin 132013, P.R. China
| | - Zhaohui Wang
- Department of Human Anatomy, College of Basic Medical Sciences, Beihua University, Jilin, Jilin 132013, P.R. China
| | - Wenbo Ju
- Department of Human Anatomy, College of Basic Medical Sciences, Beihua University, Jilin, Jilin 132013, P.R. China
| | - Dawei Wang
- Department of Human Anatomy, College of Basic Medical Sciences, Beihua University, Jilin, Jilin 132013, P.R. China
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31
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Kalamajski S, Bihan D, Bonna A, Rubin K, Farndale RW. Fibromodulin Interacts with Collagen Cross-linking Sites and Activates Lysyl Oxidase. J Biol Chem 2016; 291:7951-60. [PMID: 26893379 PMCID: PMC4825002 DOI: 10.1074/jbc.m115.693408] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Indexed: 11/28/2022] Open
Abstract
The hallmark of fibrotic disorders is a highly cross-linked and dense collagen matrix, a property driven by the oxidative action of lysyl oxidase. Other fibrosis-associated proteins also contribute to the final collagen matrix properties, one of which is fibromodulin. Its interactions with collagen affect collagen cross-linking, packing, and fibril diameter. We investigated the possibility that a specific relationship exists between fibromodulin and lysyl oxidase, potentially imparting a specific collagen matrix phenotype. We mapped the fibromodulin-collagen interaction sites using the collagen II and III Toolkit peptide libraries. Fibromodulin interacted with the peptides containing the known collagen cross-linking sites and the MMP-1 cleavage site in collagens I and II. Interestingly, the interaction sites are closely aligned within the quarter-staggered collagen fibril, suggesting a multivalent interaction between fibromodulin and several collagen helices. Furthermore, we detected an interaction between fibromodulin and lysyl oxidase (a major collagen cross-linking enzyme) and mapped the interaction site to 12 N-terminal amino acids on fibromodulin. This interaction also increases the activity of lysyl oxidase. Together, the data suggest a fibromodulin-modulated collagen cross-linking mechanism where fibromodulin binds to a specific part of the collagen domain and also forms a complex with lysyl oxidase, targeting the enzyme toward specific cross-linking sites.
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Affiliation(s)
- Sebastian Kalamajski
- From the Department of Laboratory Medical Sciences, Lund University, Medicon Village 406-3, 22363 Lund, Sweden and
| | - Dominique Bihan
- the Department of Biochemistry, Downing Site, University of Cambridge, Cambridge CB2 1QW, United Kingdom
| | - Arkadiusz Bonna
- the Department of Biochemistry, Downing Site, University of Cambridge, Cambridge CB2 1QW, United Kingdom
| | - Kristofer Rubin
- From the Department of Laboratory Medical Sciences, Lund University, Medicon Village 406-3, 22363 Lund, Sweden and
| | - Richard W Farndale
- the Department of Biochemistry, Downing Site, University of Cambridge, Cambridge CB2 1QW, United Kingdom
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Hultgårdh-Nilsson A, Borén J, Chakravarti S. The small leucine-rich repeat proteoglycans in tissue repair and atherosclerosis. J Intern Med 2015; 278:447-61. [PMID: 26477596 PMCID: PMC4616156 DOI: 10.1111/joim.12400] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Proteoglycans consist of a protein core with one or more covalently attached glycosaminoglycan (GAG) side chains and have multiple roles in the initiation and progression of atherosclerosis. Here we discuss the potential and known functions of a group of small leucine-rich repeat proteoglycans (SLRPs) in atherosclerosis. We focus on five SLRPs, decorin, biglycan, lumican, fibromodulin and PRELP, because these have been detected in atherosclerotic plaques or demonstrated to have a role in animal models of atherosclerosis. Decorin and biglycan are modified post-translationally by substitution with chondroitin/dermatan sulphate GAGs, whereas lumican, fibromodulin and PRELP have keratan sulphate side chains, and the core proteins have leucine-rich repeat (LRR) motifs that are characteristic of the LRR superfamily. The chondroitin/dermatan sulphate GAG side chains have been implicated in lipid retention in atherosclerosis. The core proteins are discussed here in the context of (i) interactions with collagens and their implications in tissue integrity, fibrosis and wound repair and (ii) interactions with growth factors, cytokines, pathogen-associated molecular patterns and cell surface receptors that impact normal physiology and disease processes such as inflammation, innate immune responses and wound healing (i.e. processes that are all important in plaque development and progression). Thus, studies of these SLRPs in the context of wound healing are providing clues about their functions in early stages of atherosclerosis to plaque vulnerability and cardiovascular disease at later stages. Understanding of signal transduction pathways regulated by the core protein interactions is leading to novel roles and therapeutic potential for these proteins in wound repair and atherosclerosis.
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Affiliation(s)
| | - J Borén
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, University of Gothenburg and Sahlgrenska University Hospital, Gothenburg, Sweden
| | - S Chakravarti
- Departments of Medicine, Ophthalmology and Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Matsushima N, Miyashita H, Enkhbayar P, Kretsinger RH. Comparative Geometrical Analysis of Leucine-Rich Repeat Structures in the Nod-Like and Toll-Like Receptors in Vertebrate Innate Immunity. Biomolecules 2015; 5:1955-78. [PMID: 26295267 PMCID: PMC4598782 DOI: 10.3390/biom5031955] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2015] [Revised: 08/10/2015] [Accepted: 08/11/2015] [Indexed: 11/25/2022] Open
Abstract
The NOD-like receptors (NLRs) and Toll-like receptors (TLRs) are pattern recognition receptors that are involved in the innate, pathogen pattern recognition system. The TLR and NLR receptors contain leucine-rich repeats (LRRs) that are responsible for ligand interactions. In LRRs short β-strands stack parallel and then the LRRs form a super helical arrangement of repeating structural units (called a coil of solenoids). The structures of the LRR domains of NLRC4, NLRP1, and NLRX1 in NLRs and of TLR1-5, TLR6, TLR8, TLR9 in TLRs have been determined. Here we report nine geometrical parameters that characterize the LRR domains; these include four helical parameters from HELFIT analysis. These nine parameters characterize well the LRR structures in NLRs and TLRs; the LRRs of NLR adopts a right-handed helix. In contrast, the TLR LRRs adopt either a left-handed helix or are nearly flat; RP105 and CD14 also adopt a left-handed helix. This geometrical analysis subdivides TLRs into four groups consisting of TLR3/TLR8/TLR9, TLR1/TLR2/TRR6, TLR4, and TLR5; these correspond to the phylogenetic tree based on amino acid sequences. In the TLRs an ascending lateral surface that consists of loops connecting the β-strand at the C-terminal side is involved in protein, protein/ligand interactions, but not the descending lateral surface on the opposite side.
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Affiliation(s)
| | | | - Purevjav Enkhbayar
- Department of Information and Computer Science, School of Engineering and Applied Sciences, National University of Mongolia, Ulaanbaatar 210646/377, Mongolia.
| | - Robert H Kretsinger
- Department of Biology, University of Virginia, Charlottesville, VA 22904, USA.
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Sattelle BM, Shakeri J, Cliff MJ, Almond A. Proteoglycans and their heterogeneous glycosaminoglycans at the atomic scale. Biomacromolecules 2015; 16:951-61. [PMID: 25645947 DOI: 10.1021/bm5018386] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Proteoglycan spatiotemporal organization underpins extracellular matrix biology, but atomic scale glimpses of this microarchitecture are obscured by glycosaminoglycan size and complexity. To overcome this, multimicrosecond aqueous simulations of chondroitin and dermatan sulfates were abstracted into a prior coarse-grained model, which was extended to heterogeneous glycosaminoglycans and small leucine-rich proteoglycans. Exploration of relationships between sequence and shape led to hypotheses that proteoglycan size is dependent on glycosaminoglycan unit composition but independent of sequence permutation. Uronic acid conformational equilibria were modulated by adjacent hexosamine sulfonation and iduronic acid increased glycosaminoglycan chain volume and rigidity, while glucuronic acid imparted chain plasticity. Consequently, block copolymeric glycosaminoglycans contained microarchitectures capable of multivalent binding to growth factors and collagen, with potential for interactional synergy at greater chain number. The described atomic scale views of proteoglycans and heterogeneous glycosaminoglycans provide structural routes to understanding their fundamental signaling and mechanical biological roles and development of new biomaterials.
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Affiliation(s)
- Benedict M Sattelle
- Faculty of Life Sciences, The University of Manchester, Manchester Institute of Biotechnology , 131 Princess Street, Manchester, M1 7DN, United Kingdom
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Synthetic covalently linked dimeric form of H2 relaxin retains native RXFP1 activity and has improved in vitro serum stability. BIOMED RESEARCH INTERNATIONAL 2015; 2015:731852. [PMID: 25685807 PMCID: PMC4317577 DOI: 10.1155/2015/731852] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/09/2014] [Accepted: 10/11/2014] [Indexed: 11/18/2022]
Abstract
Human (H2) relaxin is a two-chain peptide member of the insulin superfamily and possesses potent pleiotropic roles including regulation of connective tissue remodeling and systemic and renal vasodilation. These effects are mediated through interaction with its cognate G-protein-coupled receptor, RXFP1. H2 relaxin recently passed Phase III clinical trials for the treatment of congestive heart failure. However, its in vivo half-life is short due to its susceptibility to proteolytic degradation and renal clearance. To increase its residence time, a covalent dimer of H2 relaxin was designed and assembled through solid phase synthesis of the two chains, including a judiciously monoalkyne sited B-chain, followed by their combination through regioselective disulfide bond formation. Use of a bisazido PEG7 linker and "click" chemistry afforded a dimeric H2 relaxin with its active site structurally unhindered. The resulting peptide possessed a similar secondary structure to the native monomeric H2 relaxin and bound to and activated RXFP1 equally well. It had fewer propensities to activate RXFP2, the receptor for the related insulin-like peptide 3. In human serum, the dimer had a modestly increased half-life compared to the monomeric H2 relaxin suggesting that additional oligomerization may be a viable strategy for producing longer acting variants of H2 relaxin.
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36
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Heinegård D, Lorenzo P, Önnerfjord P, Saxne T. Articular cartilage. Rheumatology (Oxford) 2015. [DOI: 10.1016/b978-0-323-09138-1.00005-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Khaddam M, Salmon B, Le Denmat D, Tjaderhane L, Menashi S, Chaussain C, Rochefort GY, Boukpessi T. Grape seed extracts inhibit dentin matrix degradation by MMP-3. Front Physiol 2014; 5:425. [PMID: 25400590 PMCID: PMC4215787 DOI: 10.3389/fphys.2014.00425] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 10/13/2014] [Indexed: 11/22/2022] Open
Abstract
UNLABELLED Since Matrix metalloproteinases (MMPs) have been suggested to contribute to dentin caries progression, the hypothesis that MMP inhibition would affect the progression of dentin caries is clinically relevant. Grape seed extracts (GSE) have been previously reported to be natural inhibitors of MMPs. OBJECTIVE To evaluate the capacity of a GSE mouthrinse to prevent the degradation of demineralized dentin matrix by MMP-3 (stromelysin-1). MATERIALS AND METHODS Standardized blocks of dentin obtained from sound permanent teeth extracted for orthodontic reasons were demineralized with Ethylenediaminetetraacetic acid (EDTA) and pretreated either with (A) GSE (0.2% w/v), (B) amine fluoride (AmF) (20% w/v), (C) a mouthrinse which contains both, (D) placebo, (E) sodium fluoride (0.15 mg.ml(-1)), (F) PBS, (G) Chlorhexidine digluconate (CHX), or (H) zinc chloride (ZnCl2). The dentin blocks were then incubated with activated recombinant MMP-3. The supernatants were analyzed by Western Blot for several dentin matrix proteins known to be MMP-3 substrate. In parallel, scanning electron microscopy (SEM) was performed on resin replica of the dentin blocks. RESULTS Western blot analysis of the supernatants revealed that MMP-3 released from the dentin matrix small proteoglycans (decorin and biglycan) and dentin sialoprotein (DSP) in the AmF, sodium fluoride, PBS and placebo pretreated groups, but not in the GSE and mouthrinse pretreated groups. SEM examination of resin replica showed that the mouthrinse and its active components not only had an anti-MMP action but also modified the dentin surface accessibility. CONCLUSION This study shows that GSE either alone or combined with AmF as in the evaluated mouthrinse limits dentin matrix degradation. This association may be promising to prevent the progression of caries within dentin. However, the procedure should be adapted to clinically relevant durations.
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Affiliation(s)
- Mayssam Khaddam
- EA 2496, Orofacial Pathologies, Imaging and Biotherapies, Dental school, University Paris Descartes, Sorbonne Paris CitéMontrouge, France
| | - Benjamin Salmon
- EA 2496, Orofacial Pathologies, Imaging and Biotherapies, Dental school, University Paris Descartes, Sorbonne Paris CitéMontrouge, France
- Assistance Publique - Hôpitaux de Paris, Odontology Departments (Bretonneau and Charles Foix)Paris, France
| | - Dominique Le Denmat
- EA 2496, Orofacial Pathologies, Imaging and Biotherapies, Dental school, University Paris Descartes, Sorbonne Paris CitéMontrouge, France
| | - Leo Tjaderhane
- Medical Research Center Oulu, Institute of Dentistry, Oulu University Hospital and University of OuluOulu, Finland
| | - Suzanne Menashi
- Laboratoire CRRET, Université Paris-Est, Centre National de la Recherche ScientifiqueCréteil, France
| | - Catherine Chaussain
- EA 2496, Orofacial Pathologies, Imaging and Biotherapies, Dental school, University Paris Descartes, Sorbonne Paris CitéMontrouge, France
- Assistance Publique - Hôpitaux de Paris, Odontology Departments (Bretonneau and Charles Foix)Paris, France
| | - Gaël Y. Rochefort
- EA 2496, Orofacial Pathologies, Imaging and Biotherapies, Dental school, University Paris Descartes, Sorbonne Paris CitéMontrouge, France
| | - Tchilalo Boukpessi
- EA 2496, Orofacial Pathologies, Imaging and Biotherapies, Dental school, University Paris Descartes, Sorbonne Paris CitéMontrouge, France
- Assistance Publique - Hôpitaux de Paris, Odontology Departments (Bretonneau and Charles Foix)Paris, France
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Seiradake E, del Toro D, Nagel D, Cop F, Härtl R, Ruff T, Seyit-Bremer G, Harlos K, Border EC, Acker-Palmer A, Jones EY, Klein R. FLRT structure: balancing repulsion and cell adhesion in cortical and vascular development. Neuron 2014; 84:370-85. [PMID: 25374360 PMCID: PMC4210639 DOI: 10.1016/j.neuron.2014.10.008] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/02/2014] [Indexed: 11/03/2022]
Abstract
FLRTs are broadly expressed proteins with the unique property of acting as homophilic cell adhesion molecules and as heterophilic repulsive ligands of Unc5/Netrin receptors. How these functions direct cell behavior and the molecular mechanisms involved remain largely unclear. Here we use X-ray crystallography to reveal the distinct structural bases for FLRT-mediated cell adhesion and repulsion in neurons. We apply this knowledge to elucidate FLRT functions during cortical development. We show that FLRTs regulate both the radial migration of pyramidal neurons, as well as their tangential spread. Mechanistically, radial migration is controlled by repulsive FLRT2-Unc5D interactions, while spatial organization in the tangential axis involves adhesive FLRT-FLRT interactions. Further, we show that the fundamental mechanisms of FLRT adhesion and repulsion are conserved between neurons and vascular endothelial cells. Our results reveal FLRTs as powerful guidance factors with structurally encoded repulsive and adhesive surfaces.
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Affiliation(s)
- Elena Seiradake
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, OX3 7BN Oxford, UK
| | - Daniel del Toro
- Max Planck Institute of Neurobiology, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Daniel Nagel
- Max Planck Institute of Neurobiology, Am Klopferspitz 18, 82152 Martinsried, Germany; Graduate School of Systemic Neurosciences, Ludwig-Maximilians-University Munich, Großhaderner Str. 2, 82152 Planegg-Martinsried, Germany
| | - Florian Cop
- Institute of Cell Biology and Neuroscience and Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Max-von-Laue-Str. 15, 60438 Frankfurt am Main, Germany; Focus Program Translational Neurosciences, Johannes Gutenberg University Mainz, Saarstr. 21, 55122 Mainz, Germany
| | - Ricarda Härtl
- Institute of Cell Biology and Neuroscience and Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Max-von-Laue-Str. 15, 60438 Frankfurt am Main, Germany; Focus Program Translational Neurosciences, Johannes Gutenberg University Mainz, Saarstr. 21, 55122 Mainz, Germany
| | - Tobias Ruff
- Max Planck Institute of Neurobiology, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Gönül Seyit-Bremer
- Max Planck Institute of Neurobiology, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Karl Harlos
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, OX3 7BN Oxford, UK
| | - Ellen Clare Border
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, OX3 7BN Oxford, UK
| | - Amparo Acker-Palmer
- Institute of Cell Biology and Neuroscience and Buchmann Institute for Molecular Life Sciences, Goethe University Frankfurt, Max-von-Laue-Str. 15, 60438 Frankfurt am Main, Germany; Focus Program Translational Neurosciences, Johannes Gutenberg University Mainz, Saarstr. 21, 55122 Mainz, Germany
| | - E Yvonne Jones
- Division of Structural Biology, Wellcome Trust Centre for Human Genetics, University of Oxford, Roosevelt Drive, OX3 7BN Oxford, UK.
| | - Rüdiger Klein
- Max Planck Institute of Neurobiology, Am Klopferspitz 18, 82152 Martinsried, Germany; Munich Cluster for Systems Neurology (SyNergy), 80336 Munich, Germany.
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Mills RD, Mulhern TD, Liu F, Culvenor JG, Cheng HC. Prediction of the Repeat Domain Structures and Impact of Parkinsonism-Associated Variations on Structure and Function of all Functional Domains of Leucine-Rich Repeat Kinase 2 (LRRK2). Hum Mutat 2014; 35:395-412. [DOI: 10.1002/humu.22515] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2013] [Accepted: 01/08/2014] [Indexed: 12/20/2022]
Affiliation(s)
- Ryan D. Mills
- Department of Biochemistry and Molecular Biology; Bio21 Molecular Science and Biotechnology Institute; University of Melbourne; Parkville Victoria Australia
| | - Terrence D. Mulhern
- Department of Biochemistry and Molecular Biology; Bio21 Molecular Science and Biotechnology Institute; University of Melbourne; Parkville Victoria Australia
| | - Fei Liu
- Department of Chemistry & Biomolecular Sciences; Macquarie University; NSW Australia
| | - Janetta G. Culvenor
- Department of Pathology; University of Melbourne; Parkville Victoria Australia
| | - Heung-Chin Cheng
- Department of Biochemistry and Molecular Biology; Bio21 Molecular Science and Biotechnology Institute; University of Melbourne; Parkville Victoria Australia
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Islam M, Gor J, Perkins SJ, Ishikawa Y, Bächinger HP, Hohenester E. The concave face of decorin mediates reversible dimerization and collagen binding. J Biol Chem 2013; 288:35526-33. [PMID: 24169694 PMCID: PMC3853298 DOI: 10.1074/jbc.m113.504530] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Decorin, the prototypical small leucine-rich proteoglycan, binds to collagen and thereby regulates collagen assembly into fibrils. The crystal structure of the decorin core protein revealed a tight dimer formed by the association of two monomers via their concave faces (Scott, P. G., McEwan, P. A., Dodd, C. M., Bergmann, E. M., Bishop, P. N., and Bella, J. (2004) Proc. Natl. Acad. Sci. U.S.A. 101, 15633–15638). Whether decorin binds collagen as a dimer has been controversial. Using analytical ultracentrifugation, we determined a dissociation constant of 1.37 ± 0.30 μm for the mouse decorin dimer. Dimerization could be abolished by engineering glycosylation sites into the dimer interface; other interface mutants remained dimeric. The monomeric mutants were as stable as wild-type decorin in thermal unfolding experiments. Mutations on the concave face of decorin abolished collagen binding regardless of whether the mutant proteins retained the ability to dimerize or not. We conclude that the concave face of decorin mediates collagen binding and that the dimer therefore must dissociate to bind collagen.
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Affiliation(s)
- Mehwaesh Islam
- From the Department of Life Sciences, Imperial College London, London SW7 2AZ, United Kingdom
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41
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Dunkman AA, Buckley MR, Mienaltowski MJ, Adams SM, Thomas SJ, Kumar A, Beason DP, Iozzo RV, Birk DE, Soslowsky LJ. The injury response of aged tendons in the absence of biglycan and decorin. Matrix Biol 2013; 35:232-8. [PMID: 24157578 DOI: 10.1016/j.matbio.2013.10.008] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Revised: 10/14/2013] [Accepted: 10/14/2013] [Indexed: 12/13/2022]
Abstract
Recent studies have demonstrated that the small leucine-rich proteoglycans (SLRPs) biglycan and decorin impact tendon development, aging and healing in mature mice. However, despite the increased risk of tendon injury in the elderly, the role of SLRPs in tendon repair has not been investigated in aged animals. Therefore, our objective was to elucidate the influences of bigylcan and decorin on tendon healing in aged mice to relate our findings to previous work in mature mice. Since the processes of aging and healing are known to interact, our hypothesis was that aging mediates the role of biglycan and decorin on tendon healing. Patellar tendons from wild-type, biglycan-null and decorin-null mice were injured at 270 days using an established model. At 3 and 6 weeks post-surgery, structural, mechanical and biochemical analyses were performed and compared to uninjured controls. Early stage healing was inferior in biglycan-null and decorin-null mice as compared to wild type. However, tendons of all genotypes failed to exhibit improved mechanical properties between 3 and 6 weeks post-injury. In contrast, in a previous investigation of tendon healing in mature (i.e., 120 day-old) mice, only biglycan-null mice were deficient in early stage healing while decorin-null mice were deficient in late-stage healing. These results confirm that the impact of SLRPs on tendon healing is mediated by age and could inform future age-specific therapies for enhancing tendon healing.
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Affiliation(s)
- Andrew A Dunkman
- The McKay Orthopaedic Research Laboratory, University of Pennsylvania, 424 Stemmler Hall, 3450 Hamilton Walk, Philadelphia, PA 19104, USA
| | - Mark R Buckley
- The McKay Orthopaedic Research Laboratory, University of Pennsylvania, 424 Stemmler Hall, 3450 Hamilton Walk, Philadelphia, PA 19104, USA
| | - Michael J Mienaltowski
- Department of Molecular Pharmacology & Physiology, University of South Florida Morsani College of Medicine, 12901 Bruce B. Downs Blvd, MDC 8, Tampa, FL 33612, USA
| | - Sheila M Adams
- Department of Molecular Pharmacology & Physiology, University of South Florida Morsani College of Medicine, 12901 Bruce B. Downs Blvd, MDC 8, Tampa, FL 33612, USA
| | - Stephen J Thomas
- The McKay Orthopaedic Research Laboratory, University of Pennsylvania, 424 Stemmler Hall, 3450 Hamilton Walk, Philadelphia, PA 19104, USA
| | - Akash Kumar
- The McKay Orthopaedic Research Laboratory, University of Pennsylvania, 424 Stemmler Hall, 3450 Hamilton Walk, Philadelphia, PA 19104, USA
| | - David P Beason
- The McKay Orthopaedic Research Laboratory, University of Pennsylvania, 424 Stemmler Hall, 3450 Hamilton Walk, Philadelphia, PA 19104, USA
| | - Renato V Iozzo
- Department of Pathology, Anatomy & Cell Biology, Thomas Jefferson University, 1020 Locust Street, Jefferson Alumni Hall, Suite 249, Philadelphia, PA 19107, USA
| | - David E Birk
- Department of Molecular Pharmacology & Physiology, University of South Florida Morsani College of Medicine, 12901 Bruce B. Downs Blvd, MDC 8, Tampa, FL 33612, USA
| | - Louis J Soslowsky
- The McKay Orthopaedic Research Laboratory, University of Pennsylvania, 424 Stemmler Hall, 3450 Hamilton Walk, Philadelphia, PA 19104, USA.
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Obika M, Vernon RB, Gooden MD, Braun KR, Chan CK, Wight TN. ADAMTS-4 and biglycan are expressed at high levels and co-localize to podosomes during endothelial cell tubulogenesis in vitro. J Histochem Cytochem 2013; 62:34-49. [PMID: 24051360 DOI: 10.1369/0022155413507727] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Proteolysis of the extracellular matrix influences vascular growth. We examined the expression of ADAMTS-1, -4, and -5 metalloproteinases and their proteoglycan substrates versican, decorin, and biglycan as human umbilical vein endothelial cells (HUVECs) formed tubes within type I collagen gels in vitro. Tubulogenic and control HUVEC cultures expressed low levels of ADAMTS-1 and -5 mRNAs, but ADAMTS-4 mRNA was relatively abundant and was significantly elevated (as was ADAMTS-4 protein) in tubulogenic cultures versus controls. Immunocytochemistry revealed ADAMTS-4 in f-actin- and cortactin-positive podosome-like puncta in single cells and mature tubes. Tubulogenic and control cultures expressed low levels of versican and decorin mRNAs; however, peak levels of biglycan mRNA were 400- and 16,000-fold that of versican and decorin, respectively. Biglycan mRNA was highest at 3 hr, declined steadily through day 7 and, at 12 hr and beyond, was significantly lower in tubulogenic cultures than in controls. Western blots of extracellular matrix from tubulogenic cultures contained bands corresponding to biglycan and its cleavage products. By immunocytochemistry, biglycan was found in the pericellular matrix surrounding endothelial tubes and in cell-associated puncta that co-localized with ADAMTS-4 and cortactin. Collectively, our results suggest that ADAMTS-4 and its substrate biglycan are involved in tubulogenesis by endothelial cells.
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Affiliation(s)
- Masanari Obika
- Molecular Biology and Biochemistry, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Science, Okayama, Japan (MO)
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43
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Brézillon S, Pietraszek K, Maquart FX, Wegrowski Y. Lumican effects in the control of tumour progression and their links with metalloproteinases and integrins. FEBS J 2013; 280:2369-81. [PMID: 23438179 DOI: 10.1111/febs.12210] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Revised: 02/07/2013] [Accepted: 02/18/2013] [Indexed: 01/03/2023]
Abstract
Lumican is a member of the small leucine-rich proteoglycan family. It is present in numerous extracellular matrices of different tissues, such as muscle, cartilage, and cornea. In skin, lumican is present as a glycoprotein. It plays a critical role in collagen fibrillogenesis, as shown by knocking out of its gene in mice. A direct link between lumican expression and melanoma progression and metastasis has been demonstrated. Lumican was shown to impede tumour cell migration and invasion by directly interacting with the α2β1 integrin. In addition, an active sequence of the lumican core protein, called lumcorin, was identified as being responsible for inhibition of melanoma cell migration. Lumican was also shown to exert angiostatic properties by downregulating the proteolytic activity associated with endothelial cell membranes, particularly matrix metalloproteinase (MMP)-14 and MMP-9. Globally, lumican appears to be a potent agent for inhibiting tumour progression rather than tumorigenesis. However, progressive changes in proteoglycans occur in the tumour environment. The complexity and diversity of proteoglycan structure might be responsible for a variety of functions that regulate cell behaviour. Through their core protein and their glycosaminoglycan chains, proteoglycans can interact with growth factors and chemokines. These interactions affect cell signalling, motility, adhesion, growth, and apoptosis. This review summarizes recent data concerning lumican control of tumour progression in different cancers, with a particular focus on its interactions with MMPs and integrins. Its potential therapeutic implications are discussed.
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Affiliation(s)
- Stéphane Brézillon
- Laboratoire de Biochimie Médicale et de Biologie Moléculaire, CNRS FRE 3481, Université de Reims-Champagne-Ardenne, Reims, France.
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Binny Priya S, Saha S, Anishetty R, Anishetty S. A matrix based algorithm for Protein-Protein Interaction prediction using Domain-Domain Associations. J Theor Biol 2013; 326:36-42. [PMID: 23473859 DOI: 10.1016/j.jtbi.2013.02.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2012] [Revised: 01/12/2013] [Accepted: 02/25/2013] [Indexed: 12/30/2022]
Abstract
Protein-Protein Interactions (PPI) are vital to many cellular processes. The availability of high-throughput protein interaction data has provided us with an opportunity to assess domain associations in interacting proteins using computational approaches. High throughput PPI data, wherein the interaction status of every protein in the dataset has been experimentally tested against all the other proteins in the dataset contains information not only on protein interactions but also on proteins which do not interact with each other. We call such datasets "all against all" datasets. In the current study, using these datasets and the Pfam domain composition of the proteins in the sets, we have developed a matrix based method for predicting PPI. We infer positive and negative Domain-Domain Associations (DDA) by our method. We have generated more than a million domain association values which can be utilized for predicting new PPI. The performance of the algorithm was evaluated against a test set and the sensitivity and specificity was found to be 68.1% and 65.3%, respectively. The overall prediction accuracy of the algorithm with individual test sets from IntAct, DIP, 3did, iPfam databases and a literature curated set from Saccharomyces cerevisiae was found to be around 70%. The insights gained in the study have a potential application in providing leads for experimental interaction studies and understanding host pathogen interactions amongst others.
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Affiliation(s)
- S Binny Priya
- Department of Biotechnology, Anna University, Chennai 600025, India
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Godoy-Guzmán C, San Martin S, Pereda J. Proteoglycan and collagen expression during human air conducting system development. Eur J Histochem 2012; 56:e29. [PMID: 23027345 PMCID: PMC3493975 DOI: 10.4081/ejh.2012.e29] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Revised: 05/04/2012] [Accepted: 01/12/2012] [Indexed: 11/22/2022] Open
Abstract
The lung is formed from a bud that grows and divides in a dichotomous way. A bud is a new growth center which is determined by epithelial-mesenchymal interactions where proteins of the extracellular matrix (ECM) might be involved. To understand this protein participation during human lung development, we examined the expression and distribution of proteoglycans in relation to the different types of collagens during the period in which the air conducting system is installed. Using light microscopy and immunohistochemistry we evaluate the expression of collagens (I, III and VI) and proteoglycans (decorin, biglycan and lumican) between 8 to 10 weeks post fertilization and 11 to 14 weeks of gestational age of human embryo and fetus lungs. We show that decorin, lumican and all the collagen types investigated were expressed at the epithelium-mesenchymal interface, forming a sleeve around the bronchiolar ducts. In addition, biglycan was expressed in both the endothelial cells and the smooth muscle of the blood vessels. Thus, the similar distribution pattern of collagen and proteoglycans in the early developmental stages of the human lung may be closely related to the process of dichotomous division of the bronchial tree. This study provides a new insight concerning the participation of collagens and proteoglycans in the epithelial-mesenchymal interface during the period in which the air conducting system is installed in the human fetal lung.
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Affiliation(s)
- C Godoy-Guzmán
- Department of Human Embryology, School of Medicine, Universidad de Santiago de Chile, Usach, Santiago.
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Topological analysis of small leucine-rich repeat proteoglycan nyctalopin. PLoS One 2012; 7:e33137. [PMID: 22485138 PMCID: PMC3317652 DOI: 10.1371/journal.pone.0033137] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Accepted: 02/10/2012] [Indexed: 11/24/2022] Open
Abstract
Nyctalopin is a small leucine rich repeat proteoglycan (SLRP) whose function is
critical for normal vision. The absence of nyctalopin results in the complete
form of congenital stationary night blindness. Normally, glutamate released by
photoreceptors binds to the metabotropic glutamate receptor type 6 (GRM6), which
through a G-protein cascade closes the non-specific cation channel, TRPM1, on
the dendritic tips of depolarizing bipolar cells (DBCs) in the retina.
Nyctalopin has been shown to interact with TRPM1 and expression of TRPM1 on the
dendritic tips of the DBCs is dependent on nyctalopin expression. In the current
study, we used yeast two hybrid and biochemical approaches to investigate
whether murine nyctalopin was membrane bound, and if so by what mechanism, and
also whether the functional form was as a homodimer. Our results show that
murine nyctalopin is anchored to the plasma membrane by a single transmembrane
domain, such that the LRR domain is located in the extracellular space.
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Kajander T, Kuja-Panula J, Rauvala H, Goldman A. Crystal Structure and Role of Glycans and Dimerization in Folding of Neuronal Leucine-Rich Repeat Protein AMIGO-1. J Mol Biol 2011; 413:1001-15. [DOI: 10.1016/j.jmb.2011.09.032] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2011] [Revised: 09/13/2011] [Accepted: 09/15/2011] [Indexed: 10/17/2022]
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Heinegård D, Lorenzo P, Saxne T. The articular cartilage. Rheumatology (Oxford) 2011. [DOI: 10.1016/b978-0-323-06551-1.00008-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
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49
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Angheloiu GO, Haka AS, Georgakoudi I, Arendt J, Müller MG, Scepanovic OR, Evanko SP, Wight TN, Mukherjee P, Waldeck DH, Dasari RR, Fitzmaurice M, Kramer JR, Feld MS. Detection of coronary atherosclerotic plaques with superficial proteoglycans and foam cells using real-time intrinsic fluorescence spectroscopy. Atherosclerosis 2010; 215:96-102. [PMID: 21193196 DOI: 10.1016/j.atherosclerosis.2010.11.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Revised: 11/05/2010] [Accepted: 11/21/2010] [Indexed: 11/19/2022]
Abstract
OBJECTIVES The protein components of low-density lipoprotein (LDL), oxidized LDL and proteoglycans such as versican contain tryptophan, an amino acid with characteristic fluorescence features at 308 nm excitation wavelength. We hypothesize that intrinsic fluorescence spectroscopy at 308 nm excitation wavelength IFS308, a method suitable for clinical use, can identify coronary artery lesions with superficial foam cells (SFCs) and/or proteoglycans. METHODS We subjected 119 human coronary artery specimens to in vitro fluorescence and reflectance spectroscopy. We used 5 basis spectra to model IFS308, and extracted their contributions to each individual IFS308 spectrum. A diagnostic algorithm using the contributions of Total Tryptophan and fibrous cap to IFS308 was built to identify specimens with SFCs and/or proteoglycans in their top 50 μm. RESULTS We detected SFCs and/or proteoglycans, such as versican or the glycosaminoglycan hyaluronan, in 24 fibrous cap atheromas or pathologic intimal thickening (PIT) lesions. An algorithm using the contributions of Total Tryptophan and fibrous cap to IFS308 was able to identify these segments with 92% sensitivity and 80% specificity. CONCLUSION We were able to establish a set of characteristic LDL, oxidized LDL, versican and hyaluronan fluorescence spectra, ready to be used for real-time diagnosis. The IFS(308) technique detects SFCs and/or proteoglycans in fibrous cap atheromas and PIT lesions. SFCs and proteoglycans are histological markers of vulnerable plaques, and this study is a step further in developing an invasive clinical tool to detect the vulnerable atherosclerotic plaque.
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Affiliation(s)
- George O Angheloiu
- G. R. Harrison Spectroscopy Laboratory, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
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50
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Hindle KL, Bella J, Lovell SC. Quantitative analysis and prediction of curvature in leucine-rich repeat proteins. Proteins 2009; 77:342-58. [PMID: 19452560 DOI: 10.1002/prot.22440] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Leucine-rich repeat (LRR) proteins form a large and diverse family. They have a wide range of functions most of which involve the formation of protein-protein interactions. All known LRR structures form curved solenoids, although there is large variation in their curvature. It is this curvature that determines the shape and dimensions of the inner space available for ligand binding. Unfortunately, large-scale parameters such as the overall curvature of a protein domain are extremely difficult to predict. Here, we present a quantitative analysis of determinants of curvature of this family. Individual repeats typically range in length between 20 and 30 residues and have a variety of secondary structures on their convex side. The observed curvature of the LRR domains correlates poorly with the lengths of their individual repeats. We have, therefore, developed a scoring function based on the secondary structure of the convex side of the protein that allows prediction of the overall curvature with a high degree of accuracy. We also demonstrate the effectiveness of this method in selecting a suitable template for comparative modeling. We have developed an automated, quantitative protocol that can be used to predict accurately the curvature of leucine-rich repeat proteins of unknown structure from sequence alone. This protocol is available as an online resource at http://www.bioinf.manchester.ac.uk/curlrr/.
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Affiliation(s)
- K Lauren Hindle
- Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, UK
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