1
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Gahlawat S, Nanda V, Shreiber DI. Designing collagens to shed light on the multi-scale structure-function mapping of matrix disorders. Matrix Biol Plus 2024; 21:100139. [PMID: 38186852 PMCID: PMC10765305 DOI: 10.1016/j.mbplus.2023.100139] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2023] [Revised: 11/29/2023] [Accepted: 12/09/2023] [Indexed: 01/09/2024] Open
Abstract
Collagens are the most abundant structural proteins in the extracellular matrix of animals and play crucial roles in maintaining the structural integrity and mechanical properties of tissues and organs while mediating important biological processes. Fibrillar collagens have a unique triple helix structure with a characteristic repeating sequence of (Gly-X-Y)n. Variations within the repetitive sequence can cause misfolding of the triple helix, resulting in heritable connective tissue disorders. The most common variations are single-point missense mutations that lead to the substitution of a glycine residue with a bulkier amino acid (Gly → X). In this review, we will first discuss the importance of collagen's triple helix structure and how single Gly substitutions can impact its folding, structure, secretion, assembly into higher-order structures, and biological functions. We will review the role of "designer collagens," i.e., synthetic collagen-mimetic peptides and recombinant bacterial collagen as model systems to include Gly → X substitutions observed in collagen disorders and investigate their impact on structure and function utilizing in vitro studies. Lastly, we will explore how computational modeling of collagen peptides, especially molecular and steered molecular dynamics, has been instrumental in probing the effects of Gly substitutions on structure, receptor binding, and mechanical stability across multiple length scales.
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Affiliation(s)
- Sonal Gahlawat
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - Vikas Nanda
- Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
- Center for Advanced Biotechnology and Medicine, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
| | - David I. Shreiber
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Piscataway, NJ, USA
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2
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Rebello D, Wohler E, Erfani V, Li G, Aguilera AN, Santiago-Cornier A, Zhao S, Hwang SW, Steiner RD, Zhang TJ, Gurnett CA, Raggio C, Wu N, Sobreira N, Giampietro PF, Ciruna B. COL11A2 as a candidate gene for vertebral malformations and congenital scoliosis. Hum Mol Genet 2023; 32:2913-2928. [PMID: 37462524 PMCID: PMC10508038 DOI: 10.1093/hmg/ddad117] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Revised: 05/08/2023] [Accepted: 07/13/2023] [Indexed: 07/23/2023] Open
Abstract
Human vertebral malformations (VMs) have an estimated incidence of 1/2000 and are associated with significant health problems including congenital scoliosis (CS) and recurrent organ system malformation syndromes such as VACTERL (vertebral anomalies; anal abnormalities; cardiac abnormalities; tracheo-esophageal fistula; renal anomalies; limb anomalies). The genetic cause for the vast majority of VMs are unknown. In a CS/VM patient cohort, three COL11A2 variants (R130W, R1407L and R1413H) were identified in two patients with cervical VM. A third patient with a T9 hemivertebra and the R130W variant was identified from a separate study. These substitutions are predicted to be damaging to protein function, and R130 and R1407 residues are conserved in zebrafish Col11a2. To determine the role for COL11A2 in vertebral development, CRISPR/Cas9 was used to create a nonsense mutation (col11a2L642*) as well as a full gene locus deletion (col11a2del) in zebrafish. Both col11a2L642*/L642* and col11a2del/del mutant zebrafish exhibit vertebral fusions in the caudal spine, which form due to mineralization across intervertebral segments. To determine the functional consequence of VM-associated variants, we assayed their ability to suppress col11a2del VM phenotypes following transgenic expression within the developing spine. While wildtype col11a2 expression suppresses fusions in col11a2del/+ and col11a2del/del backgrounds, patient missense variant-bearing col11a2 failed to rescue the loss-of-function phenotype in these animals. These results highlight an essential role for COL11A2 in vertebral development and support a pathogenic role for two missense variants in CS.
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Affiliation(s)
- Denise Rebello
- Program in Developmental & Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
- Department of Molecular Genetics, The University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Elizabeth Wohler
- McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Vida Erfani
- Program in Developmental & Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
- Department of Molecular Genetics, The University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Guozhuang Li
- Department of Orthopedic Surgery, Key Laboratory of Big Data for Spinal Deformities, Beijing Key Laboratory for Genetic Research of Skeletal Deformity, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Alexya N Aguilera
- Department of Pediatrics, University of Illinois-Chicago, Chicago, IL 60612, USA
| | - Alberto Santiago-Cornier
- Genetic Section, San Jorge Children’s and Women’s Hospital, San Juan, Puerto Rico 00912, USA
- Department of Public Health, Ponce Health Sciences University, Ponce, Puerto Rico 00912, USA
| | - Sen Zhao
- Department of Orthopedic Surgery, Key Laboratory of Big Data for Spinal Deformities, Beijing Key Laboratory for Genetic Research of Skeletal Deformity, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
| | - Steven W Hwang
- Shriners Children’s-Philadelphia, Philadelphia, PA 19140, USA
| | - Robert D Steiner
- Department of Pediatrics, University of Wisconsin, Madison, WI 54449, USA
- Marshfield Clinic Health System, Marshfield, WI 54449, USA
| | - Terry Jianguo Zhang
- Department of Orthopedic Surgery, Key Laboratory of Big Data for Spinal Deformities, Beijing Key Laboratory for Genetic Research of Skeletal Deformity, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Christina A Gurnett
- Department of Neurology, Washington University in St. Louis, St. Louis, MO 63110, USA
| | | | - Nan Wu
- Department of Orthopedic Surgery, Key Laboratory of Big Data for Spinal Deformities, Beijing Key Laboratory for Genetic Research of Skeletal Deformity, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100730, China
| | - Nara Sobreira
- McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Philip F Giampietro
- Department of Pediatrics, University of Illinois-Chicago, Chicago, IL 60612, USA
| | - Brian Ciruna
- Program in Developmental & Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario M5G 0A4, Canada
- Department of Molecular Genetics, The University of Toronto, Toronto, Ontario M5S 1A8, Canada
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3
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Lioi M, Tengattini S, Bagatin F, Galliani S, Daly S, Massolini G, Temporini C. Development of a rapid, efficient, and reusable magnetic bead-based immunocapture system for recombinant human procollagen type II isolation from yeast fermentation broth. Anal Bioanal Chem 2023:10.1007/s00216-023-04752-1. [PMID: 37246979 DOI: 10.1007/s00216-023-04752-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 05/04/2023] [Accepted: 05/05/2023] [Indexed: 05/30/2023]
Abstract
Recombinant collagen production, especially using yeasts as expression systems, could represent a promising alternative over traditional extractive methods from animal sources, offering controllable, scalable, and high-quality products. Monitoring the efficiency and efficacy of procollagen/collagen expression, especially in the initial fermentation phases, can be difficult and time consuming, as biological matrices necessitate purification and commonly used analytical methods are only partially informative. We propose a straightforward, efficient, and reusable immunocapture system able to specifically isolate human procollagen type II from fermentation broths and to release it in few experimental steps. A recovered sample allows for a detailed characterization providing information on structural identity and integrity, which can strongly support the monitoring of fermentation processes. The immunocapture system relies on the use of protein A-coated magnetic beads which have been functionalized and cross-linked with a human anti-procollagen II antibody (average immobilization yield of 97.7%) to create a stable and reusable support for the specific procollagen fishing. We set up the binding and release conditions ensuring specific and reproducible binding with a synthetic procollagen antigen. The absence of non-specific interaction with the support and binding specificity was demonstrated, and the latter was also confirmed by a peptide mapping epitope study in reversed-phase liquid chromatography high-resolution mass spectrometry (RP-LC-HRMS). The bio-activated support proved to be reusable and stable over 21 days from the initial use. Finally, the system was successfully tested on a raw yeast fermentation sample to provide a proof of concept of the applicability within recombinant collagen production.
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Affiliation(s)
- Martina Lioi
- Department of Drug Sciences, University of Pavia, Viale Taramelli 12, 27100, Pavia, Italy
| | - Sara Tengattini
- Department of Drug Sciences, University of Pavia, Viale Taramelli 12, 27100, Pavia, Italy
| | - Francesca Bagatin
- Gnosis By Lesaffre, Via Lavoratori Autobianchi 1, 20832, Desio, Italy
| | - Stefano Galliani
- Gnosis By Lesaffre, Via Lavoratori Autobianchi 1, 20832, Desio, Italy
| | - Simona Daly
- Gnosis By Lesaffre, Via Lavoratori Autobianchi 1, 20832, Desio, Italy
| | - Gabriella Massolini
- Department of Drug Sciences, University of Pavia, Viale Taramelli 12, 27100, Pavia, Italy
| | - Caterina Temporini
- Department of Drug Sciences, University of Pavia, Viale Taramelli 12, 27100, Pavia, Italy.
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ColGen: An end-to-end deep learning model to predict thermal stability of de novo collagen sequences. J Mech Behav Biomed Mater 2021; 125:104921. [PMID: 34758444 DOI: 10.1016/j.jmbbm.2021.104921] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2021] [Accepted: 10/21/2021] [Indexed: 11/22/2022]
Abstract
Collagen is the most abundant structural protein in humans, with dozens of sequence variants accounting for over 30% of the protein in an animal body. The fibrillar and hierarchical arrangements of collagen are critical in providing mechanical properties with high strength and toughness. Due to this ubiquitous role in human tissues, collagen-based biomaterials are commonly used for tissue repairs and regeneration, requiring chemical and thermal stability over a range of temperatures during materials preparation ex vivo and subsequent utility in vivo. Collagen unfolds from a triple helix to a random coil structure during a temperature interval in which the midpoint or Tm is used as a measure to evaluate the thermal stability of the molecules. However, finding a robust framework to facilitate the design of a specific collagen sequence to yield a specific Tm remains a challenge, including using conventional molecular dynamics modeling. Here we propose a de novo framework to provide a model that outputs the Tm values of input collagen sequences by incorporating deep learning trained on a large data set of collagen sequences and corresponding Tm values. By using this framework, we are able to quickly evaluate how mutations and order in the primary sequence affect the stability of collagen triple helices. Specifically, we confirm that mutations to glycines, mutations in the middle of a sequence, and short sequence lengths cause the greatest drop in Tm values.
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5
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Stefanovic B, Stefanovic L, Manojlovic Z. Imaging of type I procollagen biosynthesis in cells reveals biogenesis in highly organized bodies; Collagenosomes. Matrix Biol Plus 2021; 12:100076. [PMID: 34278289 PMCID: PMC8261018 DOI: 10.1016/j.mbplus.2021.100076] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 06/18/2021] [Accepted: 06/18/2021] [Indexed: 10/26/2022] Open
Abstract
Mechanistic aspects of type I procollagen biosynthesis in cells are poorly understood. To provide more insight into this process we designed a system to directly image type I procollagen biogenesis by co-expression of fluorescently labeled full size procollagen α1(I) and one α2(I) polypeptides. High resolution images show that collagen α1(I) and α2(I) polypeptides are produced in coordination in discrete structures on the ER membrane, which we termed the collagenosomes. Collagenosomes are disk shaped bodies, 0.5-1 μM in diameter and 200-400 nm thick, in the core of which folding of procollagen takes place. Collagenosomes are intimately associated with the ER membrane and their formation requires intact translational machinery, suggesting that they are the sites of nascent procollagen biogenesis. Collagenosomes show little co-localization with the COPII transport vesicles, which export type I procollagen from the ER, suggesting that these two structures are distinct. LARP6 is the protein which regulates translation of type I collagen mRNAs. The characteristic organization of collagenosomes depends on binding of LARP6 to collagen mRNAs. Without LARP6 regulation, collagenosomes are poorly organized and the folding of α1(I) and α2(I) polypeptides into procollagen in their cores is diminished. This indicates that formation of collagenosomes is dependent on regulated translation of collagen mRNAs. In live cells the size, number and shape of collagenosomes show little change within several hours, suggesting that they are stable structures of type I procollagen biogenesis. This is the first report of structural organization of type I collagen biogenesis in collagenosomes, while the fluorescent reporter system based on simultaneous imaging of both type I collagen polypeptides will enable the detailed elucidation of their structure and function.
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Affiliation(s)
- Branko Stefanovic
- Department of Biomedical Sciences and Translational Science Laboratory, College of Medicine, Florida State University, 1115 West Call Street, Tallahassee, FL 32306, USA
| | - Lela Stefanovic
- Department of Biomedical Sciences and Translational Science Laboratory, College of Medicine, Florida State University, 1115 West Call Street, Tallahassee, FL 32306, USA
| | - Zarko Manojlovic
- Keck School of Medicine of University of Southern California, 1450 Biggy Street, NRT 4510, Los Angeles, CA 90033, USA
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6
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Bourgot I, Primac I, Louis T, Noël A, Maquoi E. Reciprocal Interplay Between Fibrillar Collagens and Collagen-Binding Integrins: Implications in Cancer Progression and Metastasis. Front Oncol 2020; 10:1488. [PMID: 33014790 PMCID: PMC7461916 DOI: 10.3389/fonc.2020.01488] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 07/13/2020] [Indexed: 12/14/2022] Open
Abstract
Cancers are complex ecosystems composed of malignant cells embedded in an intricate microenvironment made of different non-transformed cell types and extracellular matrix (ECM) components. The tumor microenvironment is governed by constantly evolving cell-cell and cell-ECM interactions, which are now recognized as key actors in the genesis, progression and treatment of cancer lesions. The ECM is composed of a multitude of fibrous proteins, matricellular-associated proteins, and proteoglycans. This complex structure plays critical roles in cancer progression: it functions as the scaffold for tissues organization and provides biochemical and biomechanical signals that regulate key cancer hallmarks including cell growth, survival, migration, differentiation, angiogenesis, and immune response. Cells sense the biochemical and mechanical properties of the ECM through specialized transmembrane receptors that include integrins, discoidin domain receptors, and syndecans. Advanced stages of several carcinomas are characterized by a desmoplastic reaction characterized by an extensive deposition of fibrillar collagens in the microenvironment. This compact network of fibrillar collagens promotes cancer progression and metastasis, and is associated with low survival rates for cancer patients. In this review, we highlight how fibrillar collagens and their corresponding integrin receptors are modulated during cancer progression. We describe how the deposition and alignment of collagen fibers influence the tumor microenvironment and how fibrillar collagen-binding integrins expressed by cancer and stromal cells critically contribute in cancer hallmarks.
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Affiliation(s)
| | | | | | | | - Erik Maquoi
- Laboratory of Tumor and Development Biology, GIGA-Cancer, University of Liège, Liège, Belgium
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7
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Nijhuis WH, Eastwood DM, Allgrove J, Hvid I, Weinans HH, Bank RA, Sakkers RJ. Current concepts in osteogenesis imperfecta: bone structure, biomechanics and medical management. J Child Orthop 2019; 13:1-11. [PMID: 30838070 PMCID: PMC6376438 DOI: 10.1302/1863-2548.13.180190] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
The majority of patients with osteogenesis imperfecta (OI) have mutations in the COL1A1 or COL1A2 gene, which has consequences for the composition of the bone matrix and bone architecture. The mutations result in overmodified collagen molecules, thinner collagen fibres and hypermineralization of bone tissue at a bone matrix level. Trabecular bone in OI is characterized by a lower trabecular number and connectivity as well as a lower trabecular thickness and volumetric bone mass. Cortical bone shows a decreased cortical thickness with less mechanical anisotropy and an increased pore percentage as a result of increased osteocyte lacunae and vascular porosity. Most OI patients have mutations at different locations in the COL1 gene. Disease severity in OI is probably partly determined by the nature of the primary collagen defect and its location with respect to the C-terminus of the collagen protein. The overall bone biomechanics result in a relatively weak and brittle structure. Since this is a result of all of the above-mentioned factors as well as their interactions, there is considerable variation between patients, and accurate prediction on bone strength in the individual patient with OI is difficult. Current treatment of OI focuses on adequate vitamin-D levels and interventions in the bone turnover cycle with bisphosphonates. Bisphosphonates increase bone mineral density, but the evidence on improvement of clinical status remains limited. Effects of newer drugs such as antibodies against RANKL and sclerostin are currently under investigation. This paper was written under the guidance of the Study Group Genetics and Metabolic Diseases of the European Paediatric Orthopaedic Society.
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Affiliation(s)
- W. H. Nijhuis
- Department of Orthopaedic Surgery, University Medical Centre Utrecht, Wilhelmina Children’s Hospital, The Netherlands
| | - D. M. Eastwood
- Department of Orthopaedic Surgery, Great Ormond Street Hospital, London, United Kingdom
| | - J. Allgrove
- Department of Endocrinology, Great Ormond Street Hospital, London, United Kingdom
| | - I. Hvid
- Department of Orthopaedic Surgery, Oslo University Hospital, Norway
| | - H. H. Weinans
- Department of Orthopaedic Surgery, University Medical Centre Utrecht, Wilhelmina Children’s Hospital, The Netherlands and Technical University, Delft, The Netherlands
| | - R. A. Bank
- Department of Pathology and Medical Biology, University Medical Centre Groningen, The Netherlands
| | - R. J. Sakkers
- Department of Orthopaedic Surgery, University Medical Centre Utrecht, Wilhelmina Children’s Hospital, The Netherlands, Correspondence should be sent to R. Sakkers, MD, PhD, Department of Orthopaedic Surgery University Medical Centre Utrecht, Wilhelmina Children’s Hospital, Lundlaan 6, 3548EA Utrecht, The Netherlands. E-mail:
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8
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Molecular assembly of recombinant chicken type II collagen in the yeast Pichia pastoris. SCIENCE CHINA-LIFE SCIENCES 2018; 61:815-825. [PMID: 29388039 DOI: 10.1007/s11427-017-9219-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 11/16/2017] [Indexed: 10/18/2022]
Abstract
Effective treatment of rheumatoid arthritis can be mediated by native chicken type II collagen (nCCII), recombinant peptide containing nCCII tolerogenic epitopes (CTEs), or a therapeutic DNA vaccine encoding the full-length CCOL2A1 cDNA. As recombinant CCII (rCCII) might avoid potential pathogenic virus contamination during nCCII preparation or chromosomal integration and oncogene activation associated with DNA vaccines, here we evaluated the importance of propeptide and telopeptide domains on rCCII triple helix molecular assembly. We constructed pC- and pN-procollagen (without N- or C-propeptides, respectively) as well as CTEs located in the triple helical domain lacking both propeptides and telopeptides, and expressed these in yeast Pichia pastoris host strain GS115 (his4, Mut+) simultaneously with recombinant chicken prolyl-4-hydroxylase α and β subunits. Both pC- and pN-procollagen monomers accumulated inside P. pastoris cells, whereas CTE was assembled into homotrimers with stable conformation and secreted into the supernatants, suggesting that the large molecular weight pC-or pN-procollagens were retained within the endoplasmic reticulum whereas the smaller CTEs proceeded through the secretory pathway. Furthermore, resulting recombinant chicken type II collagen pCα1(II) can induced collagen-induced arthritis (CIA) rat model, which seems to be as effective as the current standard nCCII. Notably, protease digestion assays showed that rCCII could assemble in the absence of C- and N-propeptides or telopeptides. These findings provide new insights into the minimal structural requirements for rCCII expression and folding.
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Abstract
The biochemical and biophysical properties of the extracellular matrix (ECM) dictate tissue-specific cell behaviour. The molecules that are associated with the ECM of each tissue, including collagens, proteoglycans, laminins and fibronectin, and the manner in which they are assembled determine the structure and the organization of the resultant ECM. The product is a specific ECM signature that is comprised of unique compositional and topographical features that both reflect and facilitate the functional requirements of the tissue.
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Affiliation(s)
- Janna K Mouw
- Center for Bioengineering and Tissue Regeneration, Department of Surgery, University of California, San Francisco
| | - Guanqing Ou
- 1] Center for Bioengineering and Tissue Regeneration, Department of Surgery, University of California, San Francisco. [2] University of California San Francisco and University of California Berkeley Joint Graduate Group in Bioengineering, San Francisco, California 94143, USA
| | - Valerie M Weaver
- 1] Center for Bioengineering and Tissue Regeneration, Department of Surgery, University of California, San Francisco. [2] Department of Anatomy, University of California, San Francisco. [3] Department of Bioengineering and Therapeutic Sciences, University of California, San Francisco. [4] Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research, University of California, San Francisco. [5] UCSF Helen Diller Comprehensive Cancer Center, University of California, San Francisco, California 94143, USA
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10
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Extracellular matrix assembly: a multiscale deconstruction. Nat Rev Mol Cell Biol 2014. [PMID: 25370693 DOI: 10.1038/nrm3902 10.1038/nrm3902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The biochemical and biophysical properties of the extracellular matrix (ECM) dictate tissue-specific cell behaviour. The molecules that are associated with the ECM of each tissue, including collagens, proteoglycans, laminins and fibronectin, and the manner in which they are assembled determine the structure and the organization of the resultant ECM. The product is a specific ECM signature that is comprised of unique compositional and topographical features that both reflect and facilitate the functional requirements of the tissue.
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11
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Abstract
The biochemical and biophysical properties of the extracellular matrix (ECM) dictate tissue-specific cell behaviour. The molecules that are associated with the ECM of each tissue, including collagens, proteoglycans, laminins and fibronectin, and the manner in which they are assembled determine the structure and the organization of the resultant ECM. The product is a specific ECM signature that is comprised of unique compositional and topographical features that both reflect and facilitate the functional requirements of the tissue.
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12
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Symoens S, Hulmes DJS, Bourhis JM, Coucke PJ, De Paepe A, Malfait F. Type I procollagen C-propeptide defects: study of genotype-phenotype correlation and predictive role of crystal structure. Hum Mutat 2014; 35:1330-41. [PMID: 25146735 DOI: 10.1002/humu.22677] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 07/28/2014] [Accepted: 08/08/2014] [Indexed: 11/10/2022]
Abstract
The type I procollagen carboxyterminal(C-)propeptides are crucial in directing correct assembly of the procollagen heterotrimers. Defects in these domains have anecdotally been reported in patients with Osteogenesis Imperfecta (OI) and few genotype-phenotype correlations have been described. To gain insight in the functional consequences of C-propeptide defects, we performed a systematic review of clinical, molecular, and biochemical findings in all patients in whom we identified a type I procollagen C-propeptide defect, and compared this with literature data. We report 30 unique type I procollagen C-propeptide variants, 24 of which are novel. The outcome of COL1A1 nonsense and frameshift variants depends on the location of the premature termination codon. Those located prior to 50-55 nucleotides upstream of the most 3' exon-exon junction lead to nonsense-mediated mRNA decay (NMD) and cause mild OI. Those located beyond this boundary escape NMD, generally lead to production of stable, overmodified procollagen chains, which may partly be retained intracellularly, and are usually associated with severe-to-lethal OI. Proα1(I)-C-propeptide defects that permit chain association result in more severe phenotypes than those inhibiting chain association. We demonstrate that the crystal structure of the proα1(III)-C-propeptide is a reliable tool to predict phenotypic severity for most COL1A1-C-propeptide missense variants, whereas for COL1A2-C-propeptide variants, the phenotypic outcome is milder than predicted.
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Affiliation(s)
- Sofie Symoens
- Center for Medical Genetics, Ghent University Hospital, 9000, Ghent, Belgium
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13
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Arredondo J, Lara M, Ng F, Gochez DA, Lee DC, Logia SP, Nguyen J, Maselli RA. COOH-terminal collagen Q (COLQ) mutants causing human deficiency of endplate acetylcholinesterase impair the interaction of ColQ with proteins of the basal lamina. Hum Genet 2013; 133:599-616. [PMID: 24281389 DOI: 10.1007/s00439-013-1391-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2013] [Accepted: 11/03/2013] [Indexed: 02/06/2023]
Abstract
Collagen Q (ColQ) is a key multidomain functional protein of the neuromuscular junction (NMJ), crucial for anchoring acetylcholinesterase (AChE) to the basal lamina (BL) and accumulating AChE at the NMJ. The attachment of AChE to the BL is primarily accomplished by the binding of the ColQ collagen domain to the heparan sulfate proteoglycan perlecan and the COOH-terminus to the muscle-specific receptor tyrosine kinase (MuSK), which in turn plays a fundamental role in the development and maintenance of the NMJ. Yet, the precise mechanism by which ColQ anchors AChE at the NMJ remains unknown. We identified five novel mutations at the COOH-terminus of ColQ in seven patients from five families affected with endplate (EP) AChE deficiency. We found that the mutations do not affect the assembly of ColQ with AChE to form asymmetric forms of AChE or impair the interaction of ColQ with perlecan. By contrast, all mutations impair in varied degree the interaction of ColQ with MuSK as well as basement membrane extract (BME) that have no detectable MuSK. Our data confirm that the interaction of ColQ to perlecan and MuSK is crucial for anchoring AChE to the NMJ. In addition, the identified COOH-terminal mutants not only reduce the interaction of ColQ with MuSK, but also diminish the interaction of ColQ with BME. These findings suggest that the impaired attachment of COOH-terminal mutants causing EP AChE deficiency is in part independent of MuSK, and that the COOH-terminus of ColQ may interact with other proteins at the BL.
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Affiliation(s)
- Juan Arredondo
- Department of Neurology, University of California Davis, 1515 Newton Court, Room 510, Davis, CA, 95618, USA,
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Xu F, Silva T, Joshi M, Zahid S, Nanda V. Circular permutation directs orthogonal assembly in complex collagen peptide mixtures. J Biol Chem 2013; 288:31616-23. [PMID: 24043622 DOI: 10.1074/jbc.m113.501056] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Multiple types of natural collagens specifically assemble and co-exist in the extracellular matrix. Although noncollagenous trimerization domains facilitate the folding of triple-helical regions, it is intriguing to ask whether collagen sequences are also capable of controlling heterospecific association. In this study, we designed a model system mimicking simultaneous specific assembly of two collagen heterotrimers using a genetically inspired operation, circular permutation. Previously, surface charge-pair interactions were optimized on three collagen peptides to promote the formation of an abc-type heterotrimer. Circular permutation of these sequences retained networks of stabilizing interactions, preserving both triple-helical structure and heterospecificity of assembly. Combining original peptides A, B, and C and permuted peptides D, E, and F resulted primarily in formation of A:B:C and D:E:F, a heterospecificity of 2 of 56 possible stoichiometries. This degree of specificity in collagen molecular recognition is unprecedented in natural or synthetic collagens. Analysis of natural collagen sequences indicates low similarity between the neighboring exons. Combining the synthetic collagen model and bioinformatic analysis provides insight on how fibrillar collagens might have arisen from the duplication of smaller domains.
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Affiliation(s)
- Fei Xu
- From the Center for Advanced Biotechnology and Medicine, Department of Biochemistry and Molecular Biology, Robert Wood Johnson Medical School, Rutgers University, Piscataway, New Jersey 08854
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15
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Skeletal diseases caused by mutations that affect collagen structure and function. Int J Biochem Cell Biol 2013; 45:1556-67. [DOI: 10.1016/j.biocel.2013.05.017] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2013] [Revised: 05/13/2013] [Accepted: 05/14/2013] [Indexed: 12/15/2022]
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16
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Bourhis JM, Mariano N, Zhao Y, Harlos K, Exposito JY, Jones EY, Moali C, Aghajari N, Hulmes DJS. Structural basis of fibrillar collagen trimerization and related genetic disorders. Nat Struct Mol Biol 2012; 19:1031-6. [PMID: 23001006 PMCID: PMC3465578 DOI: 10.1038/nsmb.2389] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2012] [Accepted: 08/23/2012] [Indexed: 02/07/2023]
Abstract
The C propeptides of fibrillar procollagens have crucial roles in tissue growth and repair by controlling both the intracellular assembly of procollagen molecules and the extracellular assembly of collagen fibrils. Mutations in C propeptides are associated with several, often lethal, genetic disorders affecting bone, cartilage, blood vessels and skin. Here we report the crystal structure of a C-propeptide domain from human procollagen III. It reveals an exquisite structural mechanism of chain recognition during intracellular trimerization of the procollagen molecule. It also gives insights into why some types of collagen consist of three identical polypeptide chains, whereas others do not. Finally, the data show striking correlations between the sites of numerous disease-related mutations in different C-propeptide domains and the degree of phenotype severity. The results have broad implications for understanding genetic disorders of connective tissues and designing new therapeutic strategies.
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Affiliation(s)
- Jean-Marie Bourhis
- Formation de Recherche en Evolution 3310, Institut de Biologie et Chimie des Protéines, Centre National de la Recherche Scientifique, Université Lyon 1, Lyon, France
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17
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Chan TR, Stahl PJ, Yu SM. Matrix-Bound VEGF Mimetic Peptides: Design and Endothelial Cell Activation in Collagen Scaffolds. ADVANCED FUNCTIONAL MATERIALS 2011; 21:4252-4262. [PMID: 26312060 PMCID: PMC4547390 DOI: 10.1002/adfm.201101163] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Long term survival and success of artificial tissue constructs depend greatly on vascularization. Endothelial cell (EC) differentiation and vasculature formation are dependent on spatio-temporal cues in the extracellular matrix that dynamically interact with cells, a process difficult to reproduce in artificial systems. Here we present a novel bifunctional peptide that mimics matrix-bound vascular endothelial growth factor (VEGF) and can be used to encode spatially controlled angiogenic signals in collagen scaffolds. The peptide is comprised of a collagen mimetic domain that was previously reported to bind to type I collagen by a unique hybridization mechanism, and a VEGF mimetic domain with pro-angiogenic activity. Circular dichroism and collagen binding studies confirm the triple helical structure and the collagen binding affinity of the collagen mimetic domain, and EC culture studies demonstrate the peptide's ability to induce endothelial cell morphogenesis and network formation as a matrix-bound factor in 2D and 3D collagen scaffolds. We also show spatial modification of collagen substrates with this peptide that allows localized EC activation and network formation. These results demonstrate that the peptide can be used to present spatially directed angiogenic cues in collagen scaffolds, which may be useful for engineering organized microvasculature.
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Affiliation(s)
- Tania R. Chan
- Department of Materials Science and Engineering, Institute for NanoBioTechnology, The Johns Hopkins University, 3400 N. Charles St, Baltimore, MD 21218 (USA)
| | - Patrick J. Stahl
- Department of Materials Science and Engineering, Institute for NanoBioTechnology, The Johns Hopkins University, 3400 N. Charles St, Baltimore, MD 21218 (USA)
| | - S. Michael Yu
- Department of Materials Science and Engineering, Institute for NanoBioTechnology, The Johns Hopkins University, 3400 N. Charles St, Baltimore, MD 21218 (USA)
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18
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Koyama N, Okubo Y, Nakao K, Osawa K, Bessho K. Experimental study of osteoinduction using a new material as a carrier for bone morphogenetic protein-2. Br J Oral Maxillofac Surg 2011; 49:314-8. [DOI: 10.1016/j.bjoms.2010.05.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2010] [Accepted: 05/14/2010] [Indexed: 10/19/2022]
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19
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Wirz JA, Boudko SP, Lerch TF, Chapman MS, Bächinger HP. Crystal structure of the human collagen XV trimerization domain: a potent trimerizing unit common to multiplexin collagens. Matrix Biol 2011; 30:9-15. [PMID: 20932905 PMCID: PMC3048825 DOI: 10.1016/j.matbio.2010.09.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2010] [Revised: 09/25/2010] [Accepted: 09/29/2010] [Indexed: 12/01/2022]
Abstract
Correct folding of the collagen triple helix requires a self-association step which selects and binds α-chains into trimers. Here we report the crystal structure of the trimerization domain of human type XV collagen. The trimerization domain of type XV collagen contains three monomers each composed of four β-sheets and an α-helix. The hydrophobic core of the trimer is devoid of solvent molecules and is shaped by β-sheet planes from each monomer. The trimerization domain is extremely stable and forms at picomolar concentrations. It is found that the trimerization domain of type XV collagen is structurally similar to that of type XVIII, despite only 32% sequence identity. High structural conservation indicates that the multiplexin trimerization domain represents a three dimensional fold that allows for sequence variability while retaining structural integrity necessary for tight and efficient trimerization.
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Affiliation(s)
- Jacqueline A. Wirz
- Research Department of Shriners Hospital for Children, 3101 SW Sam Jackson Pk. Rd., Portland, OR 97239, USA
- Department of Biochemistry and Molecular Biology, Oregon Health and Science University, 3191 SW Sam Jackson Pk. Rd., Portland, OR 97239, USA
| | - Sergei P. Boudko
- Research Department of Shriners Hospital for Children, 3101 SW Sam Jackson Pk. Rd., Portland, OR 97239, USA
- Department of Biochemistry and Molecular Biology, Oregon Health and Science University, 3191 SW Sam Jackson Pk. Rd., Portland, OR 97239, USA
| | - Thomas F. Lerch
- Department of Biochemistry and Molecular Biology, Oregon Health and Science University, 3191 SW Sam Jackson Pk. Rd., Portland, OR 97239, USA
| | - Michael S. Chapman
- Department of Biochemistry and Molecular Biology, Oregon Health and Science University, 3191 SW Sam Jackson Pk. Rd., Portland, OR 97239, USA
| | - Hans Peter Bächinger
- Research Department of Shriners Hospital for Children, 3101 SW Sam Jackson Pk. Rd., Portland, OR 97239, USA
- Department of Biochemistry and Molecular Biology, Oregon Health and Science University, 3191 SW Sam Jackson Pk. Rd., Portland, OR 97239, USA
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20
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Card L, Henderson N, Zhang Y, Bornstein P, Bradshaw AD. Expression in SPARC-null mice of collagen type I lacking the globular domain of the α1(I) N-propeptide results in abdominal hernias and loss of dermal collagen. Matrix Biol 2010; 29:559-64. [PMID: 20708079 DOI: 10.1016/j.matbio.2010.08.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2010] [Revised: 07/06/2010] [Accepted: 08/04/2010] [Indexed: 11/28/2022]
Abstract
The sequence encoding the N-propeptide of collagen I is characterized by significant conservation of amino acids across species; however, the function of the N-propeptide remains poorly defined. Studies in vitro have suggested that one activity of this propeptide might be to act as a feedback inhibitor of collagen I synthesis. To determine whether the N-propeptide contributed to decreased collagen content in SPARC-null mice, mice carrying a deletion of exon 2, which encodes the globular domain of the N-propeptide of collagen I, were crossed to SPARC-null animals. Mice lacking SPARC and expressing collagen I without the globular domain of the N-propeptide were viable and fertile. However, a significant number of animals developed abdominal hernias within the first 2 months of life with an approximate 20% penetrance (~35% of males). The dermis of SPARC-null/exon 2-deleted mice was thinner and contained fewer large collagen fibers in comparison with wild-type or in either single transgenic animal. The average collagen fibril diameter of exon 2-deleted mice did not significantly differ from wild-type mice (WT: 87.9 nm versus exon 2-deleted: 88.2 nm), whereas SPARC-null/exon 2-deleted fibrils were smaller than that of SPARC-null dermis (SPARC-null: 60.2 nm, SPARC-null/exon 2-deleted: 40.8 nm). As measured by hydroxyproline analysis, double transgenic skin biopsies contained significantly less collagen than those of wild-type, those of exon 2-deleted, and those of SPARC-null biopsies. Acetic acid extraction of collagen from skin biopsies revealed an increase in the proportion of soluble collagen in the SPARC-null/exon 2-deleted mice. These results support a function of the N-propeptide of collagen I in facilitating incorporation and stabilization of collagen I into the insoluble ECM and argue against a primary function of the N-propeptide as a negative regulator of collagen synthesis.
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Affiliation(s)
- Lauren Card
- Gazes Cardiac Research Institute, Division of Cardiology, Dept. of Medicine, Medical University of South Carolina, Charleston, SC 29425, United States
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21
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The collagen V homotrimer [alpha1(V)](3) production is unexpectedly favored over the heterotrimer [alpha1(V)](2)alpha2(V) in recombinant expression systems. J Biomed Biotechnol 2010; 2010:376927. [PMID: 20625483 PMCID: PMC2896673 DOI: 10.1155/2010/376927] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2009] [Revised: 03/19/2010] [Accepted: 03/20/2010] [Indexed: 11/30/2022] Open
Abstract
Collagen V, a fibrillar collagen with important functions in tissues, assembles into distinct
chain associations. The most abundant and ubiquitous molecular form is the heterotrimer
[α1(V)]2α2(V). In the attempt to produce high levels of recombinant collagen V heterotrimer
for biomedical device uses, and to identify key factors that drive heterotrimeric chain
association, several cell expression systems (yeast, insect, and mammalian cells) have been
assayed by cotransfecting the human proα1(V) and proα2(V) chain cDNAs. Suprisingly, in
all recombinant expression systems, the formation of [α1(V)]3 homotrimers was considerably favored over the heterotrimer. In addition, pepsin-sensitive proα2(V) chains were found in HEK-293 cell media indicating that these cells lack quality control proteins preventing
collagen monomer secretion. Additional transfection with Hsp47 cDNA, encoding the
collagen-specific chaperone Hsp47, did not increase heterotrimer production. Double
immunofluorescence with antibodies against collagen V α-chains showed that, contrary to fibroblasts, collagen V α-chains did not colocalized intracellularly in transfected cells. Monensin treatment had no effect on the heterotrimer production. The heterotrimer production seems to require specific machinery proteins, which are not endogenously
expressed in the expression systems. The different constructs and transfected cells we have
generated represent useful tools to further investigate the mechanisms of collagen trimer
assembly.
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22
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Vincourt JB, Etienne S, Cottet J, Delaunay C, Malanda B, Lionneton F, Sirveaux F, Netter P, Plénat F, Mainard D, Vignaud JM, Magdalou J. C-Propeptides of Procollagens Iα1 and II that Differentially Accumulate in Enchondromas versus Chondrosarcomas Regulate Tumor Cell Survival and Migration. Cancer Res 2010; 70:4739-48. [DOI: 10.1158/0008-5472.can-10-0046] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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23
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24
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Chung HJ, Steplewski A, Uitto J, Fertala A. Fluorescent protein markers to tag collagenous proteins: the paradigm of procollagen VII. Biochem Biophys Res Commun 2009; 390:662-6. [PMID: 19822129 PMCID: PMC2796180 DOI: 10.1016/j.bbrc.2009.10.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2009] [Accepted: 10/06/2009] [Indexed: 10/20/2022]
Abstract
Fluorescent proteins are powerful markers allowing tracking expression, intracellular localization, and translocation of tagged proteins but their effects on the structure and assembly of complex extracellular matrix proteins has not been investigated. Here, we analyzed the utility of fluorescent proteins as markers for procollagen VII, a triple-helical protein critical for the integrity of dermal-epidermal junction. DNA constructs encoding a red fluorescent protein-tagged wild type mini-procollagen VII alpha chain and green fluorescent protein-tagged alpha chains harboring selected mutations were genetically engineered. These DNA constructs were co-expressed in HEK-293 cells and the assembly of heterogeneous triple-helical mini-procollagen VII molecules was analyzed. Immunoprecipitation and fluorescence resonance energy transfer assays demonstrated that the presence of different fluorescent protein markers at the C-termini of individual alpha chains neither altered formation of triple-helical molecules nor affected their secretion to the extracellular space. Our study provides a basis for employing fluorescent proteins as tags for complex structural proteins of extracellular matrix.
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Affiliation(s)
- Hye Jin Chung
- Department of Dermatology and Cutaneous Biology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, 19107, U.S.A
| | - Andrzej Steplewski
- Department of Dermatology and Cutaneous Biology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, 19107, U.S.A
| | - Jouni Uitto
- Department of Dermatology and Cutaneous Biology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, 19107, U.S.A
| | - Andrzej Fertala
- Department of Dermatology and Cutaneous Biology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania, 19107, U.S.A
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25
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Franzke CW, Bruckner-Tuderman L, Blobel CP. Shedding of collagen XVII/BP180 in skin depends on both ADAM10 and ADAM9. J Biol Chem 2009; 284:23386-96. [PMID: 19574220 PMCID: PMC2749112 DOI: 10.1074/jbc.m109.034090] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2009] [Indexed: 11/06/2022] Open
Abstract
Collagen XVII is a transmembrane collagen and the major autoantigen of the autoimmune skin blistering disease bullous pemphigoid. Collagen XVII is proteolytically released from the membrane, and the pathogenic epitope harbors the cleavage site for its ectodomain shedding, suggesting that proteolysis has an important role in regulating the function of collagen XVII in skin homeostasis. Previous studies identified ADAMs 9, 10, and 17 as candidate collagen XVII sheddases and suggested that ADAM17 is a major sheddase. Here we show that ADAM17 only indirectly affects collagen XVII shedding and that ADAMs 9 and 10 are the most prominent collagen XVII sheddases in primary keratinocytes because (a) collagen XVII shedding was not stimulated by phorbol esters, known activators of ADAM17, (b) constitutive and calcium influx-stimulated shedding was sensitive to the ADAM10-selective inhibitor GI254023X and was strongly reduced in Adam10(-/-) cells, (c) there was a 55% decrease in constitutive collagen XVII ectodomain shedding from Adam9(-/-) keratinocytes, and (d) H(2)O(2) enhanced ADAM9 expression and stimulated collagen XVII shedding in skin and keratinocytes of wild type mice but not of Adam9(-/-) mice. We conclude that ADAM9 and ADAM10 can both contribute to collagen XVII shedding in skin with an enhanced relative contribution of ADAM9 in the presence of reactive oxygen species. These results provide critical new insights into the identity and regulation of the major sheddases for collagen XVII in keratinocytes and skin and have implications for the treatment of blistering diseases of the skin.
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Affiliation(s)
- Claus-Werner Franzke
- From the Arthritis and Tissue Degeneration Program, Hospital for Special Surgery, New York, New York 10021
- the Department of Dermatology, University of Freiburg, 79104 Freiburg, Germany, and
| | - Leena Bruckner-Tuderman
- the Department of Dermatology, University of Freiburg, 79104 Freiburg, Germany, and
- the Freiburg Institute of Advanced Studies, School of Life Sciences, D-79085 Freiburg, Germany
| | - Carl P. Blobel
- From the Arthritis and Tissue Degeneration Program, Hospital for Special Surgery, New York, New York 10021
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26
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Chung HJ, Jensen DA, Gawron K, Steplewski A, Fertala A. R992C (p.R1192C) Substitution in collagen II alters the structure of mutant molecules and induces the unfolded protein response. J Mol Biol 2009; 390:306-18. [PMID: 19433093 PMCID: PMC2749300 DOI: 10.1016/j.jmb.2009.05.004] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2008] [Revised: 04/30/2009] [Accepted: 05/05/2009] [Indexed: 11/18/2022]
Abstract
We investigated the molecular bases of spondyloepiphyseal dysplasia (SED) associated with the R992C (p.R1192C) substitution in collagen II. At the protein level, we analyzed the structure and integrity of mutant molecules, and at the cellular level, we specifically studied the effects of the presence of the R992C collagen II on the biological processes taking place in host cells. Our studies demonstrated that mutant collagen II molecules were characterized by altered electrophoretic mobility, relatively low thermostability, the presence of atypical disulfide bonds, and slow rates of secretion into the extracellular space. Analyses of cellular responses to the presence of the mutant molecules showed that excessive accumulation of thermolabile collagen II was associated with the activation of an "unfolded protein response" and an increase in apoptosis of host cells. Collectively, these data suggest that molecular mechanisms of SED may be driven not only by structural changes in the architecture of extracellular collagenous matrices, but also by intracellular processes activated by the presence of mutant collagen II molecules.
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Affiliation(s)
- Hye Jin Chung
- Department of Dermatology and Cutaneous Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
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27
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Hintze V, Steplewski A, Ito H, Jensen DA, Rodeck U, Fertala A. Cells expressing partially unfolded R789C/p.R989C type II procollagen mutant associated with spondyloepiphyseal dysplasia undergo apoptosis. Hum Mutat 2008; 29:841-51. [PMID: 18383211 DOI: 10.1002/humu.20736] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Vera Hintze
- Department of Dermatology and Cutaneous Biology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA
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28
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Bodian DL, Madhan B, Brodsky B, Klein TE. Predicting the clinical lethality of osteogenesis imperfecta from collagen glycine mutations. Biochemistry 2008; 47:5424-32. [PMID: 18412368 DOI: 10.1021/bi800026k] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Osteogenesis imperfecta (OI), or brittle bone disease, often results from missense mutation of one of the conserved glycine residues present in the repeating Gly-X-Y sequence characterizing the triple-helical region of type I collagen. A composite model was developed for predicting the clinical lethality resulting from glycine mutations in the alpha1 chain of type I collagen. The lethality of mutations in which bulky amino acids are substituted for glycine is predicted by their position relative to the N-terminal end of the triple helix. The effect of a Gly --> Ser mutation is modeled by the relative thermostability of the Gly-X-Y triplet on the carboxy side of the triplet containing the substitution. This model also predicts the lethality of Gly --> Ser and Gly --> Cys mutations in the alpha2 chain of type I collagen. The model was validated with an independent test set of six novel Gly --> Ser mutations. The hypothesis derived from the model of an asymmetric interaction between a Gly --> Ser mutation and its neighboring residues was tested experimentally using collagen-like peptides. Consistent with the prediction, a significant decrease in stability, calorimetric enthalpy, and folding time was observed for a peptide with a low-stability triplet C-terminal to the mutation compared to a similar peptide with the low-stability triplet on the N-terminal side. The computational and experimental results together relate the position-specific effects of Gly --> Ser mutations to the local structural stability of collagen and lend insight into the etiology of OI.
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Affiliation(s)
- Dale L Bodian
- Genetics Department, School of Medicine, Stanford University, Stanford, California 94305, USA
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29
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Freimark B, Clark D, Pernasetti F, Nickel J, Myszka D, Baeuerle PA, Van Epps D. Targeting of humanized antibody D93 to sites of angiogenesis and tumor growth by binding to multiple epitopes on denatured collagens. Mol Immunol 2007; 44:3741-50. [PMID: 17507095 DOI: 10.1016/j.molimm.2007.03.027] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2007] [Revised: 03/27/2007] [Accepted: 03/29/2007] [Indexed: 02/07/2023]
Abstract
A humanized, affinity-matured IgG1 antibody, called D93, and its parental murine IgM HUI77 have been shown to specifically bind denatured collagens and thereby inhibit angiogenesis and tumor growth in various animal models. In this study, we have identified epitopes for both HUI77 and D93 on human collagen type IV. Several tryptic D93-binding peptides were identified by Western blot analysis and protein sequencing. Epitopes for D93 were ultimately identified by screening a synthetic 16-mer peptide array spanning immunoreactive tryptic peptides. D93 reacted with a peptide corresponding to alpha1(IV) P(1337)-Y(1352) that could inhibit binding of both D93 and HUI77 to denatured collagen IV in a concentration-dependent manner. A 9-mer peptide corresponding to alpha1(IV) G(1344)-Y(1352) showed maximum inhibition of D93 and HUI77 antibody binding to denatured collagen IV, and was critically dependent on the presence of hydroxyproline. D93 bound with similar affinity to denatured collagen IV and synthetic peptides with a K(D) of 1-10 microM for monovalent and of 30-63 nM for bivalent binding. Potential epitopes for D93 are highly repeated in multiple collagen types of diverse vertebrate species explaining reactivity of D93 with denatured collagens types I-V from chicken to man. Our data suggest that D93 inhibits angiogenesis and tumor growth by blockade of cryptic bioactive signals on proteolyzed collagens with importance for growth of tumors and new blood vessels.
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30
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Bhardwaj A, Olia AS, Walker-Kopp N, Cingolani G. Domain organization and polarity of tail needle GP26 in the portal vertex structure of bacteriophage P22. J Mol Biol 2007; 371:374-87. [PMID: 17574574 DOI: 10.1016/j.jmb.2007.05.051] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2007] [Revised: 05/11/2007] [Accepted: 05/17/2007] [Indexed: 10/23/2022]
Abstract
The attachment of tailed bacteriophages to the host cell wall as well as the penetration and injection of the viral genome into the host is mediated by the virion tail complex. In phage P22, a member of the Podoviridae family that infects Salmonella enterica, the tail contains an approximately 220 A elongated protein needle, previously identified as tail accessory factor gp26. Together with tail factors gp4 and gp10, gp26 is critical to close the portal protein channel and retain the viral DNA inside the capsid. By virtue of its topology and position in the virion, the tail needle gp26 is thought to function as a penetrating device to perforate the Salmonella cell wall. Here, we define the domain organization of gp26, characterize the structural determinants for its stability, and define the polarity of the gp26 assembly into the phage portal vertex structure. We have found that the N-terminal 27 residues of gp26 form a functional domain that, although not required for gp26 trimerization and overall stability, is essential for the correct attachment to gp10, which is thought to plug the portal vertex structure. The region downstream of domain I, domain II, folds into helical core, which exhibits four trimerization octad repeats with consensus Ile-xx-Leu-xxx-Val/Tyr. We demonstrate that in vitro, domain II represents the main self-assembling, highly stable trimerization core of gp26, which retains a folded conformation both in an anhydrous environment and in the presence of 10% SDS. The C terminus of gp26, immediately downstream of domain II, contains a beta-sheet-rich region, domain III, and a short coiled coil, domain IV, which, although not required for gp26 trimerization, enhance its thermodynamic stability. We propose that domains III and IV of the tail needle form the tip utilized by the phage to penetrate the host cell wall.
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Affiliation(s)
- Anshul Bhardwaj
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, 750, E. Adams Street, Syracuse, NY 13210, USA
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31
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Towler MR, Wren A, Rushe N, Saunders J, Cummins NM, Jakeman PM. Raman spectroscopy of the human nail: a potential tool for evaluating bone health? JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2007; 18:759-63. [PMID: 17136606 DOI: 10.1007/s10856-006-0018-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2006] [Accepted: 10/10/2006] [Indexed: 05/12/2023]
Abstract
Dual X-ray absorptiometry (DEXA) is the current gold standard for the diagnosis of osteoporosis. However, patients can suffer osteoporotic fractures despite normal bone mineral density, partly because of unmeasured influences of both the protein and mineral phases of bone that are affected in osteoporosis. There is currently no clinically applicable method of evaluating the health of the protein phase. The proteins in human nail (keratin) and bone (collagen) require sulphation and disulphide bond (S-S) formation for structural integrity and disorders of either sulphur metabolism or cystathione beta-synthase can lead to structural abnormalities in these tissues. Raman protein spectra provide a method of non-invasive measurement of the degree of sulphation of structurally related proteins that may be indicative of bone health. Raman spectroscopy was used to evaluate the disulphide (S-S) content of fingernails. The nail samples came from from 169 women (84 pre- and 85 post-menopausal), of which 39 had a history of osteoporotic fracture. BMD was measured by DXA at the spine. Analyses included parametric and non-parametric tests, dependent on the distribution of the test variable. Mean disulphide content of the nail reduced with age and was slightly higher in pre-, compared to post-menopausal women (P = 0.187). Significantly lower disulphide content was observed in nails obtained from subjects with a history of fracture (P = 0.025). When either disulphide content or BMD was used as a predictor, the odds ratio of these two measures were found to be comparable predictors for fracture status. This suggests that measurements of change in the protein phase of structural proteins such as keratin in the human nail may be correlated with clinically relevant changes in bone proteins that are important in fracture risk.
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Affiliation(s)
- M R Towler
- Materials and Surface Science Institute, University of Limerick, National Technological Park, Limerick, Ireland.
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32
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Khoshnoodi J, Cartailler JP, Alvares K, Veis A, Hudson BG. Molecular recognition in the assembly of collagens: terminal noncollagenous domains are key recognition modules in the formation of triple helical protomers. J Biol Chem 2006; 281:38117-21. [PMID: 17082192 DOI: 10.1074/jbc.r600025200] [Citation(s) in RCA: 140] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The alpha-chains of the collagen superfamily are encoded with information that specifies self-assembly into fibrils, microfibrils, and networks that have diverse functions in the extracellular matrix. A key self-organizing step, common to all collagen types, is trimerization that selects, binds, and registers cognate alpha-chains for assembly of triple helical protomers that subsequently oligomerize into specific suprastructures. In this article, we review recent findings on the mechanism of chain selection and infer that terminal noncollagenous domains function as recognition modules in trimerization and are therefore key determinants of specificity in the assembly of suprastructures. This mechanism is also illustrated with computer-generated animations.
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Affiliation(s)
- Jamshid Khoshnoodi
- Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232-2372, USA
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33
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Oganesian A, Au S, Horst JA, Holzhausen LC, Macy AJ, Pace JM, Bornstein P. The NH2-terminal propeptide of type I procollagen acts intracellularly to modulate cell function. J Biol Chem 2006; 281:38507-18. [PMID: 17018525 PMCID: PMC3086210 DOI: 10.1074/jbc.m607536200] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The function of the NH(2)-terminal propeptide of type I procollagen (N-propeptide) is poorly understood. We now show that a recombinant trimeric N-propeptide interacts with transforming growth factor-beta1 and BMP2 and exhibits functional effects in stably transfected cells. The synthesis of N-propeptide by COS-7 cells results in an increase in phosphorylation of Akt and Smad3 and is associated with a marked reduction in type I procollagen synthesis and impairment in adhesion. In C2C12 cells, N-propeptide inhibits the osteoblastic differentiation induced by BMP2. Our data suggest that these effects are mediated by the interaction of N-propeptide with an intracellular receptor in the secretory pathway, because they are not observed when recombinant N-propeptide is added to the culture medium of either COS-7 or C2C12 cells. Both the binding of N-propeptide to cytokines and its functional properties are entirely dependent on the exon 2-encoded globular domain, and a mutation that substitutes a serine for a highly conserved cysteine in exon 2 abolishes its function. Our findings suggest that N-propeptide performs an important feedback regulatory function and provides a rationale for the prominence of a homotrimeric form of type I procollagen (alpha1 trimer) during vertebrate development.
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Affiliation(s)
- Anush Oganesian
- Department of Biochemistry, University of Washington, Seattle, Washington 98195
| | - Sandra Au
- Department of Biochemistry, University of Washington, Seattle, Washington 98195
| | - Jeremy A. Horst
- Department of Biochemistry, University of Washington, Seattle, Washington 98195
| | - Lars C. Holzhausen
- Department of Biochemistry, University of Washington, Seattle, Washington 98195
| | - Athena J. Macy
- Department of Biochemistry, University of Washington, Seattle, Washington 98195
| | - James M. Pace
- Department of Pathology, University of Washington, Seattle, Washington 98195
| | - Paul Bornstein
- Department of Biochemistry, University of Washington, Seattle, Washington 98195
- Department of Medicine, University of Washington, Seattle, Washington 98195
- To whom correspondence should be addressed: Dept. of Biochemistry, Box 357350, University of Washington, Seattle WA 98195. Tel.: 206-543-1789; Fax: 206-685-4426;
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34
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Hyde TJ, Bryan MA, Brodsky B, Baum J. Sequence dependence of renucleation after a Gly mutation in model collagen peptides. J Biol Chem 2006; 281:36937-43. [PMID: 16998200 DOI: 10.1074/jbc.m605135200] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Missense mutations in the collagen triple helix that replace one Gly residue in the (Gly-X-Y)(n) repeating pattern by a larger amino acid have been shown to delay triple helix folding. One hypothesis is that such mutations interfere with the C- to N-terminal directional propagation and that the identity of the residues immediately N-terminal to the mutation site may determine the delay time and the degree of clinical severity. Model peptides are designed to clarify the role of tripeptide sequences N-terminal to the mutation site, with respect to length, stability, and nucleation propensity, to complete triple helix folding. Two sets of peptides with different N-terminal sequences, one with the natural sequence alpha1(I) 886-900, which is just adjacent to the Gly(901) mutation, and one with a GPO(GAO)(3) sequence, which occurs at alpha1(I) 865-879, are studied by CD and NMR. Placement of the five tripeptides of the natural alpha1(I) collagen sequence N-terminal to the Gly to Ala mutation site results in a peptide that is folded only C-terminal to the mutation site. In contrast, the presence of the Hyp-rich sequence GPO(GAO)(3) N-terminal to the mutation allows complete refolding in the presence of the mutation. The completely folded peptide contains an ordered central region with unusual hydrogen bonding while maintaining standard triple helix structure at the N- and C-terminal ends. These peptide results suggest that the location and sequences of downstream regions favorable for renucleation could be the key factor in the completion of a triple helix N-terminal to a mutation.
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Affiliation(s)
- Timothy J Hyde
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, USA
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35
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Novelli J, Page AP, Hodgkin J. The C terminus of collagen SQT-3 has complex and essential functions in nematode collagen assembly. Genetics 2006; 172:2253-67. [PMID: 16452136 PMCID: PMC1456373 DOI: 10.1534/genetics.105.053637] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The nematode exoskeleton is a multilayered structure secreted by the underlying hypodermal cells and mainly composed of small collagens, which are encoded by a large gene family. In previous work, we reported analysis of the C. elegans dpy-31 locus, encoding a hypodermally expressed zinc-metalloprotease of the BMP-1/TOLLOID family essential for viability and cuticle deposition. We have generated a large set of extragenic suppressors of dpy-31 lethality, most of which we show here to be allelic to the cuticle collagen genes sqt-3 and dpy-17. We analyzed the interaction among dpy-31, sqt-3, and dpy-17 using a SQT-3-specific antiserum, which was employed in immunofluorescence experiments. Our results support a role for DPY-31 in SQT-3 extracellular processing and suggest that the SQT-3 C-terminal nontrimeric region serves multiple roles during SQT-3 assembly. Different missense mutations of this region have diverse phenotypic consequences, including cold-sensitive lethality. Furthermore, the biochemical and genetic data indicate that the extracellular assemblies of DPY-17 and SQT-3 are interdependent, most likely because the collagens are incorporated into the same cuticular substructure. We find that absence of DPY-17 causes extensive intracellular retention of SQT-3, indicating that formation of the SQT-3-DPY-17 polymer could begin in the intracellular environment before secretion.
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Affiliation(s)
- Jacopo Novelli
- Genetics Unit, Department of Biochemistry, University of Oxford, United Kingdom
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36
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Kishimoto T, Morihara Y, Osanai M, Ogata SI, Kamitakahara M, Ohtsuki C, Tanihara M. Synthesis of poly(Pro-Hyp-Gly)(n) by direct poly-condensation of (Pro-Hyp-Gly)(n), where n=1, 5, and 10, and stability of the triple-helical structure. Biopolymers 2005; 79:163-72. [PMID: 16094625 DOI: 10.1002/bip.20348] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Pro-Hyp-Gly is a characteristic amino acid sequence found in fibrous collagens, and (Pro-Hyp-Gly)(10), which has been widely used as a collagen-model peptide, forms a stable triple-helical structure. Here, we synthesized polypeptides consisting of the Pro-Hyp-Gly sequence by direct poly-condensation of (Pro-Hyp-Gly)(n), where n=1, 5, and 10, using 1-hydroxybenzotriazole and 1-ethyl-3-(3-dimethyl-aminopropyl)-carbodiimide hydrochloride in both phosphate buffer (pH=7.4) and dimethylsulfoxide (DMSO) solutions for 48 h at 20 degrees C. The reaction of (Pro-Hyp-Gly)(5) and (Pro-Hyp-Gly)(10) in DMSO successfully gave polypeptides with molecular weights over 10,000, whereas low molecular weight products were obtained by reaction in phosphate buffer (pH=7.4). In contrast, Pro-Hyp-Gly at a concentration of 50 mg/mL in phosphate buffer (pH=7.4) gave polypeptides with molecular weights over 10,000. The Fourier transform infrared (FTIR) and (1)H nuclear magnetic resonance (NMR) spectra of poly(Pro-Hyp-Gly)(10) revealed that the polymerization of (Pro-Hyp-Gly)(10) described in this report had no side reactions. Each polypeptide obtained shows a collagen-like triple-helical structure, and the triple-helical structures of poly(Pro-Hyp-Gly) and poly(Pro-Hyp-Gly)(10) were stable up to T=80 degrees C, which suggests that the high molecular weight promotes stability of the triple-helical structure, in addition to the high Hyp content. Furthermore, transmission electron microscopy (TEM) observations show that poly(Pro-Hyp-Gly)(10) aggregates to form nanofiber-like structures about 10 nm in width, which suggests that a Pro-Hyp-Gly repeating sequence contains enough information for triple-helix formation, and for subsequent nanofiber-like structure formation.
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Affiliation(s)
- Takahiro Kishimoto
- Graduate School of Materials Science, Nara Institute of Science and Technology, 8916-5 Takayama, IkomaNara 630-0192, Japan
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37
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Yang L, Carlson SG, McBurney D, Horton WE. Multiple Signals Induce Endoplasmic Reticulum Stress in Both Primary and Immortalized Chondrocytes Resulting in Loss of Differentiation, Impaired Cell Growth, and Apoptosis. J Biol Chem 2005; 280:31156-65. [PMID: 16000304 DOI: 10.1074/jbc.m501069200] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The endoplasmic reticulum is the site of synthesis and folding of secretory proteins and is sensitive to changes in the internal and external environment of the cell. Both physiological and pathological conditions may perturb the function of the endoplasmic reticulum, resulting in endoplasmic reticulum stress. The chondrocyte is the only resident cell found in cartilage and is responsible for synthesis and turnover of the abundant extracellular matrix and may be sensitive to endoplasmic reticulum stress. Here we report that glucose withdrawal, tunicamycin, and thapsigargin induce up-regulation of GADD153 and caspase-12, two markers of endoplasmic reticulum stress, in both primary chondrocytes and a chondrocyte cell line. Other agents such as interleukin-1beta or tumor necrosis factor alpha induced a minimal or no induction of GADD153, respectively. The endoplasmic reticulum stress resulted in decreased chondrocyte growth based on cell counts, up-regulation of p21, and decreased PCNA expression. In addition, perturbation of endoplasmic reticulum function resulted in decreased accumulation of an Alcian Blue positive matrix by chondrocytes and decreased expression of type II collagen at the protein level. Further, quantitative real-time PCR was used to demonstrate a down-regulation of steady state mRNA levels coding for aggrecan, collagen II, and link protein in chondrocytes exposed to endoplasmic reticulum stress-inducing conditions. Ultimately, endoplasmic reticulum stress resulted in chondrocyte apoptosis, as evidenced by DNA fragmentation and annexin V staining. These findings have potentially important implications regarding consequences of endoplasmic reticulum stress in cartilage biology.
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Affiliation(s)
- Ling Yang
- Department of Anatomy, Northeastern Ohio University College of Medicine, Rootstown, Ohio 44272, USA
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38
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Thomas EK, Nakamura M, Wienke D, Isacke CM, Pozzi A, Liang P. Endo180 binds to the C-terminal region of type I collagen. J Biol Chem 2005; 280:22596-605. [PMID: 15817460 DOI: 10.1074/jbc.m501155200] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Type I collagen is a fibril-forming heterotrimer composed of two alpha1 and one alpha2 chains and plays a crucial role in cell-matrix adhesion and cell differentiation. Through a comprehensive differential display screening of oncogenic ras target genes, we have shown that the alpha1 chain of type I collagen (col1a1) is markedly down-regulated by the ras oncogene through the mitogen-activated protein kinase pathway. Although ras-transformed cells are no longer able to produce and secrete endogenous collagen, they can still adhere to exogenous collagen, suggesting that the cells express a collagen binding factor(s) on the cell surface. When the region of col1a1 encompassing the C-terminal glycine repeat and C-prodomain (amino acids 1000-1453) was affinity-labeled with human placental alkaline phosphatase, the secreted trimeric fusion protein could bind to the surface of Ras-transformed cells. Using biochemical purification followed by matrix-assisted laser desorption/ionization mass spectrometry analysis, we identified this collagen binding factor as Endo180 (uPARAP, CD280), a member of the mannose receptor family. Ectopic expression of Endo180 in CosE5 cells followed by in situ staining and quantitative binding assays confirmed that Endo180 indeed recognizes and binds to placental alkaline phosphatase. The interaction between Endo180 and the C-terminal region of type I collagen appears to play an important role in cell-matrix adhesion.
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MESH Headings
- Alkaline Phosphatase/metabolism
- Animals
- Blotting, Northern
- Blotting, Western
- COS Cells
- Cell Adhesion
- Cell Differentiation
- Cell Line
- Cell Separation
- Collagen/metabolism
- Collagen/pharmacology
- Collagen Type I/chemistry
- Collagen Type I/metabolism
- Collagen Type I, alpha 1 Chain
- DNA, Complementary/metabolism
- Down-Regulation
- Drug Combinations
- Electrophoresis, Polyacrylamide Gel
- Enzyme Inhibitors/pharmacology
- Fibroblasts/metabolism
- Fibronectins/chemistry
- Flow Cytometry
- Gene Expression Profiling
- Glycine/chemistry
- Humans
- Laminin/pharmacology
- MAP Kinase Signaling System
- Models, Molecular
- Molecular Sequence Data
- Peptides/chemistry
- Phenotype
- Placenta/enzymology
- Protein Binding
- Protein Structure, Tertiary
- Proteoglycans/pharmacology
- RNA Interference
- RNA, Small Interfering/metabolism
- Rats
- Receptors, Mitogen/chemistry
- Receptors, Mitogen/metabolism
- Recombinant Fusion Proteins/chemistry
- Recombinant Fusion Proteins/metabolism
- Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
- Time Factors
- Transfection
- ras Proteins/metabolism
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Affiliation(s)
- Emily K Thomas
- Vanderbilt-Ingram Cancer Center, Department of Cancer Biology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, USA
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39
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Marutani T, Yamamoto A, Nagai N, Kubota H, Nagata K. Accumulation of type IV collagen in dilated ER leads to apoptosis in Hsp47-knockout mouse embryos via induction of CHOP. J Cell Sci 2004; 117:5913-22. [PMID: 15522896 DOI: 10.1242/jcs.01514] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Hsp47 is an endoplasmic reticulum (ER)-resident molecular chaperone that is specific for collagen. In Hsp47(-/-) mouse embryos at 9.5 days postcoitus (dpc), immunostaining indicated the absence of type IV collagen, but not of laminin and nidogen-1, in the basement membrane (BM). Electron immunomicroscopy revealed accumulation of type IV collagen in dilated ERs, but not in the BM of Hsp47(-/-) embryos, whereas it was only present in the BM in Hsp47(+/+) embryos. The BM structures stained with anti-laminin and anti-nidogen-1 antibody became disrupted in Hsp47(-/-) embryos at 10.5 dpc. Thus, in the absence of type IV collagen in the BM owing to the lack of Hsp47, the structure of the BM cannot be maintained during the dramatic morphological changes that take place around 10.5 dpc. Type IV collagen is therefore indispensable for the maintenance of BM structures during the late-stage development of mouse embryos, although not essential for the initial formation of the BM. Just before the death of Hsp47(-/-) embryos, DNA fragmentation typical of apoptosis was observed at 10.5 dpc together with significantly upregulated CHOP mRNA expression. ER stress caused by the accumulation of misfolded collagen may have induced apoptosis in Hsp47-knockout embryos through the upregulation of CHOP.
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Affiliation(s)
- Toshihiro Marutani
- Department of Molecular and Cellular Biology and CREST/JST, Institute for Frontier Medical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8397, Japan
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40
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Buevich AV, Silva T, Brodsky B, Baum J. Transformation of the mechanism of triple-helix peptide folding in the absence of a C-terminal nucleation domain and its implications for mutations in collagen disorders. J Biol Chem 2004; 279:46890-5. [PMID: 15299012 DOI: 10.1074/jbc.m407061200] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Folding abnormalities of the triple helix have been demonstrated in collagen diseases such as osteogenesis imperfecta in which the mutation leads to the substitution of a single Gly in the (Gly-X-Y)n sequence pattern by a larger residue. Model peptides can be used to clarify the details of normal collagen folding and the consequences of the interruption of that folding by a Gly substitution. NMR and CD studies show that placement of a (GPO)4 nucleation domain at the N terminus rather than the C terminus of a native collagen sequence allows the formation of a stable triple helix but alters the folding mechanism. Although C- to N-terminal directional folding occurs when the nucleation domain is at the C terminus, there is no preferential folding direction when the nucleation domain is at the N terminus. The lack of zipper-like directional folding does not interfere with triple-helix formation, and when a Gly residue is replaced by Ser to model an osteogenesis imperfecta mutation, the peptide with the N-terminal (GPO)4 domain can still form a good triple helix N-terminal to the mutation site. These peptide studies raise the possibility that mutant collagen could fold in a C to N direction in a zipper-like manner up to the mutation site and that completion of the triple helix N-terminal to the mutation would involve an alternative mechanism.
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Affiliation(s)
- Alexei V Buevich
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, New Jersey 08854, USA
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41
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Franzke CW, Tasanen K, Borradori L, Huotari V, Bruckner-Tuderman L. Shedding of collagen XVII/BP180: structural motifs influence cleavage from cell surface. J Biol Chem 2004; 279:24521-9. [PMID: 15047704 DOI: 10.1074/jbc.m308835200] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Collagen XVII/BP180, an epithelial adhesion molecule, belongs to the group of collagenous transmembrane proteins, which are characterized by ectodomain shedding. We recently showed that ADAMs can cleave collagen XVII, but also that furin participates in this process (Franzke, C. W., Tasanen, K., Schäcke, H., Zhou, Z., Tryggvason, K., Mauch, C., Zigrino, P., Sunnarborg, S., Lee, D. C., Fahrenholz, F., and Bruckner-Tuderman, L. (2002) EMBO J. 21, 5026-5035). To define the cleavage region in the juxtamembranous NC16A linker domain and assess its structure and requirements for shedding, we constructed deletion mutants of the NC16A domain, expressed them in COS-7 cells, and analyzed their structural integrity and shedding behavior. A mutant lacking the furin consensus sequence was shed in a normal manner, demonstrating that furin does not cleave collagen XVII but rather activates ADAMs (a disintegrin and metalloproteinase). Large deletions of the NC16A domain prevented shedding, and analysis of defined smaller deletions pointed to the stretch of amino acid residues 528-547 as important for sheddase recognition and cleavage. Secondary protein structure predictions showed that deletion of this stretch resulted in an NC16A domain with a positive net charge and an amphipathic alpha-helix, which can cause conformational changes in the collagen XVII homotrimer. Assessment of triple-helix folding of the mutants revealed a lower thermal stability of all non-shed variants than of wild-type collagen XVII or the shed mutants. In contrast, deletion of the putative nucleation site for triple-helix folding of collagenous transmembrane proteins did not affect folding of collagen XVII. The data indicate that the conformation of the NC16A domain and steric availability of the cleavage site influence shedding and is important for folding of collagen XVII.
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Affiliation(s)
- Claus-Werner Franzke
- Department of Dermatology, University of Freiburg, Hauptstrasse 7, 79106 Freiburg, Germany
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42
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Steplewski A, Majsterek I, McAdams E, Rucker E, Brittingham RJ, Ito H, Hirai K, Adachi E, Jimenez SA, Fertala A. Thermostability Gradient in the Collagen Triple Helix Reveals its Multi-domain Structure. J Mol Biol 2004; 338:989-98. [PMID: 15111062 DOI: 10.1016/j.jmb.2004.03.037] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2003] [Revised: 03/04/2004] [Accepted: 03/08/2004] [Indexed: 11/25/2022]
Abstract
A triple-helical conformation and stability at physiological temperature are critical for the mechanical and biological functions of the fibril-forming collagens. Here, we characterized the role of consecutive domains of collagen II in stabilizing the triple helix. Analysis of melting temperatures of genetically engineered collagen-like proteins consisting of tandem repeats of the D1, D2, D3 or D4 collagen II periods revealed the presence of a gradient of thermostability along the collagen molecule with thermolabile N-terminal domains and thermostable C-terminal domains. These results imply a multi-domain character of the collagen triple helix. Assays of thermostabilities of the Arg75Cys and Arg789Cys collagen II mutants suggest that, in contrast to the thermostable domains, the thermolabile domains are able to accommodate amino acid substitutions without altering the thermostability of the entire collagen molecule.
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Affiliation(s)
- Andrzej Steplewski
- Department of Dermatology and Cutaneous Biology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA.
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43
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Abstract
The folding of collagen in vitro is very slow and presents difficulties in reaching equilibrium, a feature that may have implications for in vivo collagen function. Peptides serve as good model systems for examining equilibrium thermal transitions in the collagen triple helix. Investigations were carried out to ascertain whether a range of synthetic triple-helical peptides of varying sequences can reach equilibrium, and whether the triple helix to unfolded monomer transition approximates a two-state model. The thermal transitions for all peptides studied are fully reversible given sufficient time. Isothermal experiments were carried out to obtain relaxation times at different temperatures. The slowest relaxation times, on the order of 10-15 h, were observed at the beginning of transitions, and were shown to result from self-association limited by the low concentration of free monomers, rather than cis-trans isomerization. Although the fit of the CD equilibrium transition curves and the concentration dependence of T(m) values support a two-state model, the more rigorous comparison of the calorimetric enthalpy to the van't Hoff enthalpy indicates the two-state approximation is not ideal. Previous reports of melting curves of triple-helical host-guest peptides are shown to be a two-state kinetic transition, rather than an equilibrium transition.
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Affiliation(s)
- Anton V Persikov
- UMDNJ-Robert Wood Johnson Medical School, 675 Hoes Lane, Piscataway, NJ 08854, USA
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44
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Papanikolopoulou K, Forge V, Goeltz P, Mitraki A. Formation of Highly Stable Chimeric Trimers by Fusion of an Adenovirus Fiber Shaft Fragment with the Foldon Domain of Bacteriophage T4 Fibritin. J Biol Chem 2004; 279:8991-8. [PMID: 14699113 DOI: 10.1074/jbc.m311791200] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The folding of beta-structured, fibrous proteins is a largely unexplored area. A class of such proteins is used by viruses as adhesins, and recent studies revealed novel beta-structured motifs for them. We have been studying the folding and assembly of adenovirus fibers that consist of a globular C-terminal domain, a central fibrous shaft, and an N-terminal part that attaches to the viral capsid. The globular C-terminal, or "head" domain, has been postulated to be necessary for the trimerization of the fiber and might act as a registration signal that directs its correct folding and assembly. In this work, we replaced the head of the fiber by the trimerization domain of the bacteriophage T4 fibritin, termed "foldon." Two chimeric proteins, comprising the foldon domain connected at the C-terminal end of four fiber shaft repeats with or without the use of a natural linker sequence, fold into highly stable, SDS-resistant trimers. The structural signatures of the chimeric proteins as seen by CD and infrared spectroscopy are reported. The results suggest that the foldon domain can successfully replace the fiber head domain in ensuring correct trimerization of the shaft sequences. Biological implications and implications for engineering highly stable, beta-structured nanorods are discussed.
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45
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McAlinden A, Smith TA, Sandell LJ, Ficheux D, Parry DAD, Hulmes DJS. Alpha-helical coiled-coil oligomerization domains are almost ubiquitous in the collagen superfamily. J Biol Chem 2003; 278:42200-7. [PMID: 12920133 DOI: 10.1074/jbc.m302429200] [Citation(s) in RCA: 61] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Alpha-helical coiled-coils are widely occurring protein oligomerization motifs. Here we show that most members of the collagen superfamily contain short, repeating heptad sequences typical of coiled coils. Such sequences are found at the N-terminal ends of the C-propeptide domains in all fibrillar procollagens. When fused C-terminal to a reporter molecule containing a collagen-like sequence that does not spontaneously trimerize, the C-propeptide heptad repeats induced trimerization. C-terminal heptad repeats were also found in the oligomerization domains of the multiplexins (collagens XV and XVIII). N-terminal heptad repeats are known to drive trimerization in transmembrane collagens, whereas fibril-associated collagens with interrupted triple helices, as well as collagens VII, XIII, XXIII, and XXV, were found to contain heptad repeats between collagen domains. Finally, heptad repeats were found in the von Willebrand factor A domains known to be involved in trimerization of collagen VI, as well as in collagen VII. These observations suggest that coiled-coil oligomerization domains are widely used in the assembly of collagens and collagen-like proteins.
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Affiliation(s)
- Audrey McAlinden
- Department of Orthopedic Surgery, Washington University School of Medicine, Barnes-Jewish Hospital, St. Louis, MO 63110, USA
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Majsterek I, McAdams E, Adachi E, Dhume ST, Fertala A. Prospects and limitations of the rational engineering of fibrillar collagens. Protein Sci 2003; 12:2063-72. [PMID: 12931004 PMCID: PMC2324002 DOI: 10.1110/ps.0385103] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Recombinant collagens are attractive proteins for a number of biomedical applications. To date, significant progress was made in the large-scale production of nonmodified recombinant collagens; however, engineering of novel collagen-like proteins according to customized specifications has not been addressed. Herein we investigated the possibility of rational engineering of collagen-like proteins with specifically assigned characteristics. We have genetically engineered two DNA constructs encoding multi-D4 collagens defined as collagen-like proteins, consisting primarily of a tandem of the collagen II D4 periods that correspond to the biologically active region. We have also attempted to decrease enzymatic degradation of novel collagen by mutating a matrix metalloproteinase 1 cleavage site present in the D4 period. We demonstrated that the recombinant collagen alpha-chains consisting predominantly of the D4 period but lacking most of the other D periods found in native collagen fold into a typical collagen triple helix, and the novel procollagens are correctly processed by procollagen N-proteinase and procollagen C-proteinase. The nonmutated multi-D4 collagen had a normal melting point of 41 degrees C and a similar carbohydrate content as that of control. In contrast, the mutant multi-D4 collagen had a markedly lower thermostability of 36 degrees C and a significantly higher carbohydrate content. Both collagens were cleaved at multiple sites by matrix metalloproteinase 1, but the rate of hydrolysis of the mutant multi-D4 collagen was lower. These results provide a basis for the rational engineering of collagenous proteins and identifying any undesirable consequences of altering the collagenous amino acid sequences.
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Affiliation(s)
- Ireneusz Majsterek
- Department of Dermatology and Cutaneous Biology, Jefferson Medical College, Jefferson Institute of Molecular Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania 19107, USA
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Pakkanen O, Hämäläinen ER, Kivirikko KI, Myllyharju J. Assembly of stable human type I and III collagen molecules from hydroxylated recombinant chains in the yeast Pichia pastoris. Effect of an engineered C-terminal oligomerization domain foldon. J Biol Chem 2003; 278:32478-83. [PMID: 12805365 DOI: 10.1074/jbc.m304405200] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The C-propeptides of the pro alpha chains of type I and type III procollagens are believed to be essential for correct chain recognition and chain assembly in these molecules. We studied here whether the 30-kDa C-propeptides of the human pC alpha 1(I), pC alpha 2(I), and pC alpha 1(III) chains, i.e. pro alpha chains lacking their N-propeptides, can be replaced by foldon, a 29-amino acid sequence normally located at the C terminus of the polypeptide chains in the bacteriophage T4 fibritin. The alpha foldon chains were expressed in Pichia pastoris cells that also expressed the two types of subunit of human prolyl 4-hydroxylase; the foldon domain was subsequently removed by pepsin treatment, which also digests non-triple helical collagen chains, whereas triple helical collagen molecules are resistant to it. The foldon domain was found to be very effective in chain assembly, as expression of the alpha 1(I)foldon or alpha 1(III)foldon chains gave about 2.5-3-fold the amount of pepsin-resistant type I or type III collagen homotrimers relative to those obtained using the authentic C-propeptides. In contrast, expression of chains with no oligomerization domain led to very low levels of pepsin-resistant molecules. Expression of alpha 2(I)foldon chains gave no pepsin-resistant molecules at all, indicating that in addition to control at the level of the C-propeptide other restrictions at the level of the collagen domain exist that prevent the formation of stable [alpha 2(I)]3 molecules. Co-expression of alpha 1(I)foldon and alpha 2(I)foldon chains led to an efficient assembly of heterotrimeric molecules, their amounts being about 2-fold those obtained with the authentic C-propeptides and the alpha 1(I) to alpha 2(I) ratio being 1.91 +/- 0.31 (S.D.). As the foldon sequence contains no information for chain recognition, our data indicate that chain assembly is influenced not only by the C-terminal oligomerization domain but also by determinants present in the alpha chain domains.
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Affiliation(s)
- Outi Pakkanen
- Collagen Research Unit, Biocenter Oulu and Department of Medical Biochemistry and Molecular Biology, University of Oulu, FIN-90014 Oulu, Finland
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Bon S, Ayon A, Leroy J, Massoulié J. Trimerization domain of the collagen tail of acetylcholinesterase. Neurochem Res 2003; 28:523-35. [PMID: 12675141 DOI: 10.1023/a:1022821306722] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
In the collagen-tailed forms of cholinesterases, each subunit of a specific triple helical collagen, ColQ, may be attached through a proline-rich domain (PRAD) situated in its N-terminal noncollagenous region, to tetramers of acetylcholinesterase (AChE) or butyrylcholinesterase (BChE). This heteromeric assembly ensures the functional anchoring of AChE in extracellulare matrices, for example, at the neuromuscular junction. In this study, we analyzed the influence of deletions in the noncollagenous C-terminal region of ColQ on its capacity to form a triple helix. We show that an 80-residue segment located downstream of the collagenous regions contains the trimerization domain, that it can form trimers without the collagenous regions, and that a pair of cysteines located at the N-boundary of this domain facilitates oligomerization, although it is not absolutely required. We further show that AChE subunits can associate with nonhelical collagen ColQ monomers, forming ColQ-associated tetramers (G4-Q), which are secreted or are anchored at the cell surface when the C-terminal domain of ColQ is replaced by a GPI-addition signal.
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Affiliation(s)
- Suzanne Bon
- Laboratoire de Neurobiologie Cellulaire et Moléculaire, CNRS UMR 8544, Ecole Normale Supérieure, 46 rue d'Ulm, 75005 Paris, France
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de Wolf F. Chapter V Collagen and gelatin. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s0921-0423(03)80005-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2023]
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Horino Y, Takahashi S, Miura T, Takahashi Y. Prolonged hypoxia accelerates the posttranscriptional process of collagen synthesis in cultured fibroblasts. Life Sci 2002; 71:3031-45. [PMID: 12408871 DOI: 10.1016/s0024-3205(02)02142-2] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Molecular oxygen is essential for metazoan life. Hypoxia, a reduced oxygen condition, induces systemic and cellular responses for acclimation to the limited oxygen availability. Multicellularity of metazoans is maintained on extracellular matrices. Previously, we demonstrated that acute hypoxia up-regulated the prolyl 4-hydroxylase alpha(I) subunit, the rate-limiting subunit for the hydroxylation of proline residues of procollagens (Y. Takahashi, S. Takahashi, Y. Shiga, T. Yoshimi, and T Miura, 2000, J. Biol. Chem., 275, 14139-14146). The formation of hydroxyproline is an essential posttranscriptional process for stabilization of the helical trimer of procollagen polypeptides at physiological temperature. In this present study, we cultured fetal rat lung fibroblasts for up to 9 days and examined the effects of prolonged hypoxia on the level of procollagen mRNA in the cells and the posttranscriptional steps of collagen synthesis. Hypoxia accelerated the deposition of collagen molecules. These enhancements in hypoxic cultures were observed with or without ascorbic acid in the culture medium. The steady-state level of procollagen alpha1(I) mRNA was not affected by the prolonged hypoxia. In contrast, the mRNA and protein levels of the prolyl 4-hydroxylase alpha(I) subunit were increased by hypoxic culture under both ascorbic acid-sufficient and -deficient conditions. These results suggest that hypoxic enhancement of the posttranscriptional step of collagen synthesis contributed to the accelerated deposition of collagen fibrils.
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Affiliation(s)
- Yoko Horino
- Laboratory of Environmental Molecular Physiology, School of Life Science, Tokyo University of Pharmacy and Life Science, 1432-1 Horinouchi, Tokyo 192-0392, Hachioji, Japan
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