1
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Hendershot LM, Buck TM, Brodsky JL. The Essential Functions of Molecular Chaperones and Folding Enzymes in Maintaining Endoplasmic Reticulum Homeostasis. J Mol Biol 2024; 436:168418. [PMID: 38143019 DOI: 10.1016/j.jmb.2023.168418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Revised: 12/18/2023] [Accepted: 12/19/2023] [Indexed: 12/26/2023]
Abstract
It has been estimated that up to one-third of the proteins encoded by the human genome enter the endoplasmic reticulum (ER) as extended polypeptide chains where they undergo covalent modifications, fold into their native structures, and assemble into oligomeric protein complexes. The fidelity of these processes is critical to support organellar, cellular, and organismal health, and is perhaps best underscored by the growing number of disease-causing mutations that reduce the fidelity of protein biogenesis in the ER. To meet demands encountered by the diverse protein clientele that mature in the ER, this organelle is populated with a cadre of molecular chaperones that prevent protein aggregation, facilitate protein disulfide isomerization, and lower the activation energy barrier of cis-trans prolyl isomerization. Components of the lectin (glycan-binding) chaperone system also reside within the ER and play numerous roles during protein biogenesis. In addition, the ER houses multiple homologs of select chaperones that can recognize and act upon diverse peptide signatures. Moreover, redundancy helps ensure that folding-compromised substrates are unable to overwhelm essential ER-resident chaperones and enzymes. In contrast, the ER in higher eukaryotic cells possesses a single member of the Hsp70, Hsp90, and Hsp110 chaperone families, even though several homologs of these molecules reside in the cytoplasm. In this review, we discuss specific functions of the many factors that maintain ER quality control, highlight some of their interactions, and describe the vulnerabilities that arise from the absence of multiple members of some chaperone families.
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Affiliation(s)
- Linda M Hendershot
- Department of Tumor Cell Biology, St. Jude Children's Research Hospital, Memphis, TN 38105, United States.
| | - Teresa M Buck
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, United States
| | - Jeffrey L Brodsky
- Department of Biological Sciences, University of Pittsburgh, Pittsburgh, PA 15260, United States
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2
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Ishikawa Y, Bonna A, Gould DB, Farndale RW. Local Net Charge State of Collagen Triple Helix Is a Determinant of FKBP22 Binding to Collagen III. Int J Mol Sci 2023; 24:15156. [PMID: 37894834 PMCID: PMC10607241 DOI: 10.3390/ijms242015156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Revised: 10/10/2023] [Accepted: 10/10/2023] [Indexed: 10/29/2023] Open
Abstract
Mutations in the FKBP14 gene encoding the endoplasmic reticulum resident collagen-related proline isomerase FK506 binding protein 22 kDa (FKBP22) result in kyphoscoliotic Ehlers-Danlos Syndrome (EDS), which is characterized by a broad phenotypic outcome. A plausible explanation for this outcome is that FKBP22 participates in the biosynthesis of subsets of collagen types: FKBP22 selectively binds to collagens III, IV, VI, and X, but not to collagens I, II, V, and XI. However, these binding mechanisms have never been explored, and they may underpin EDS subtype heterogeneity. Here, we used collagen Toolkit peptide libraries to investigate binding specificity. We observed that FKBP22 binding was distributed along the collagen helix. Further, it (1) was higher on collagen III than collagen II peptides and it (2) was correlated with a positive peptide charge. These findings begin to elucidate the mechanism by which FKBP22 interacts with collagen.
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Affiliation(s)
- Yoshihiro Ishikawa
- Department of Ophthalmology, University of California San Francisco, School of Medicine, San Francisco, CA 941583, USA
| | - Arkadiusz Bonna
- Department of Biochemistry, Downing Site, Cambridge CB2 1QW, UK
| | - Douglas B. Gould
- Department of Ophthalmology, University of California San Francisco, School of Medicine, San Francisco, CA 941583, USA
- Department of Anatomy, University of California, San Francisco, CA 94143, USA
- Cardiovascular Research Institute, University of California, San Francisco, CA 94158, USA
- Bakar Aging Research Institute, University of California, San Francisco, CA 94143, USA
- Institute for Human Genetics, University of California, San Francisco, CA 94143, USA
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3
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Ghosh DK, Udupa P, Shrikondawar AN, Bhavani GS, Shah H, Ranjan A, Girisha KM. Mutant MESD links cellular stress to type I collagen aggregation in osteogenesis imperfecta type XX. Matrix Biol 2023; 115:81-106. [PMID: 36526215 PMCID: PMC7615836 DOI: 10.1016/j.matbio.2022.12.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 11/19/2022] [Accepted: 12/12/2022] [Indexed: 12/15/2022]
Abstract
Aberrant forms of endoplasmic reticulum (ER)-resident chaperones are implicated in loss of protein quality control in rare diseases. Here we report a novel mutation (p.Asp233Asn) in the ER retention signal of MESD by whole exome sequencing of an individual diagnosed with osteogenesis imperfecta (OI) type XX. While MESDD233N has similar stability and chaperone activity as wild-type MESD, its mislocalization to cytoplasm leads to imbalance of ER proteostasis, resulting in improper folding and aggregation of proteins, including LRP5 and type I collagen. Aggregated LRP5 loses its plasma membrane localization to disrupt the expression of WNT-responsive genes, such as BMP2, BMP4, in proband fibroblasts. We show that MESD is a direct chaperone of pro-α1(I) [COL1A1], and absence of MESDD233N in ER results in cytosolic type I collagen aggregates that remain mostly not secreted. While cytosolic type I collagen aggregates block the intercellular nanotubes, decreased extracellular type I collagen also results in loss of interaction of ITGB1 with type I collagen and weaker attachment of fibroblasts to matrix. Although proband fibroblasts show increased autophagy to degrade the aggregated type I collagen, an overall cellular stress overwhelms the proband fibroblasts. In summary, we present an essential chaperone function of MESD for LRP5 and type I collagen and demonstrating how the D233N mutation in MESD correlates with impaired WNT signaling and proteostasis in OI.
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Affiliation(s)
- Debasish Kumar Ghosh
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka 576104, India.
| | - Prajna Udupa
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka 576104, India
| | - Akshaykumar Nanaji Shrikondawar
- Computational and Functional Genomics Group, Centre for DNA Fingerprinting and Diagnostics, Hyderabad 500039, Telangana, India
| | - Gandham SriLakshmi Bhavani
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka 576104, India
| | - Hitesh Shah
- Department of Pediatric Orthopedics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka 576104, India
| | - Akash Ranjan
- Computational and Functional Genomics Group, Centre for DNA Fingerprinting and Diagnostics, Hyderabad 500039, Telangana, India
| | - Katta M Girisha
- Department of Medical Genetics, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka 576104, India.
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4
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Lee KJ, Rambault L, Bou-Gharios G, Clegg PD, Akhtar R, Czanner G, van ‘t Hof R, Canty-Laird EG. Collagen (I) homotrimer potentiates the osteogenesis imperfecta (oim) mutant allele and reduces survival in male mice. Dis Model Mech 2022; 15:dmm049428. [PMID: 36106514 PMCID: PMC9555767 DOI: 10.1242/dmm.049428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 08/23/2022] [Indexed: 11/20/2022] Open
Abstract
The osteogenesis imperfecta murine (oim) model with solely homotrimeric (α1)3 type I collagen, owing to a dysfunctional α2(I) collagen chain, has a brittle bone phenotype, implying that the (α1)2(α2)1 heterotrimer is required for physiological bone function. Here, we comprehensively show, for the first time, that mice lacking the α2(I) chain do not have impaired bone biomechanical or structural properties, unlike oim homozygous mice. However, Mendelian inheritance was affected in male mice of both lines, and male mice null for the α2(I) chain exhibited age-related loss of condition. Compound heterozygotes were generated to test whether gene dosage was responsible for the less-severe phenotype of oim heterozygotes, after allelic discrimination showed that the oim mutant allele was not downregulated in heterozygotes. Compound heterozygotes had impaired bone structural properties compared to those of oim heterozygotes, albeit to a lesser extent than those of oim homozygotes. Hence, the presence of heterotrimeric type I collagen in oim heterozygotes alleviates the effect of the oim mutant allele, but a genetic interaction between homotrimeric type I collagen and the oim mutant allele leads to bone fragility.
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Affiliation(s)
- Katie J. Lee
- Department of Musculoskeletal and Ageing Science, Institute of Life Course and Medical Sciences, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool L7 8TX, UK
| | - Lisa Rambault
- Département d'Informatique, Université de Poitiers, 86073 Poitiers Cedex 9, France
| | - George Bou-Gharios
- Department of Musculoskeletal and Ageing Science, Institute of Life Course and Medical Sciences, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool L7 8TX, UK
| | - Peter D. Clegg
- Department of Musculoskeletal and Ageing Science, Institute of Life Course and Medical Sciences, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool L7 8TX, UK
- The Medical Research Council Versus Arthritis Centre for Integrated Research into Musculoskeletal Ageing (CIMA), Institute of Life Course and Medical Sciences, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool L7 8TX, UK
| | - Riaz Akhtar
- Department of Mechanical, Materials and Aerospace Engineering, School of Engineering, University of Liverpool, Liverpool L69 3GH, UK
| | - Gabriela Czanner
- School of Computer Science and Mathematics, Faculty of Engineering and Technology, Liverpool John Moores University, Byrom Street, Liverpool L3 3AF, UK
| | - Rob van ‘t Hof
- Department of Musculoskeletal and Ageing Science, Institute of Life Course and Medical Sciences, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool L7 8TX, UK
| | - Elizabeth G. Canty-Laird
- Department of Musculoskeletal and Ageing Science, Institute of Life Course and Medical Sciences, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool L7 8TX, UK
- The Medical Research Council Versus Arthritis Centre for Integrated Research into Musculoskeletal Ageing (CIMA), Institute of Life Course and Medical Sciences, University of Liverpool, William Henry Duncan Building, 6 West Derby Street, Liverpool L7 8TX, UK
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5
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Garibaldi N, Besio R, Dalgleish R, Villani S, Barnes AM, Marini JC, Forlino A. Dissecting the phenotypic variability of osteogenesis imperfecta. Dis Model Mech 2022; 15:275408. [PMID: 35575034 PMCID: PMC9150118 DOI: 10.1242/dmm.049398] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Accepted: 03/16/2022] [Indexed: 12/24/2022] Open
Abstract
Osteogenesis imperfecta (OI) is a heterogeneous family of collagen type I-related diseases characterized by bone fragility. OI is most commonly caused by single-nucleotide substitutions that replace glycine residues or exon splicing defects in the COL1A1 and COL1A2 genes that encode the α1(I) and α2(I) collagen chains. Mutant collagen is partially retained intracellularly, impairing cell homeostasis. Upon secretion, it assembles in disorganized fibrils, altering mineralization. OI is characterized by a wide range of clinical outcomes, even in the presence of identical sequence variants. Given the heterotrimeric nature of collagen I, its amino acid composition and the peculiarity of its folding, several causes may underlie the phenotypic variability of OI. A deep analysis of entries regarding glycine and splice site collagen substitution of the largest publicly available patient database reveals a higher risk of lethal phenotype for carriers of variants in α1(I) than in α2(I) chain. However, splice site variants are predominantly associated with lethal phenotype when they occur in COL1A2. In addition, lethality is increased when mutations occur in regions of importance for extracellular matrix interactions. Both extracellular and intracellular determinants of OI clinical severity are discussed in light of the findings from in vitro and in vivo OI models. Combined with meticulous tracking of clinical cases via a publicly available database, the available OI animal models have proven to be a unique tool to shed light on new modulators of phenotype determination for this rare heterogeneous disease.
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Affiliation(s)
- Nadia Garibaldi
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, 27100 Pavia, Italy
| | - Roberta Besio
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, 27100 Pavia, Italy
| | - Raymond Dalgleish
- Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, United Kingdom
| | - Simona Villani
- Department of Public Health and Experimental and Forensic Medicine, Unit of Biostatistics and Clinical Epidemiology, University of Pavia, 27100 Pavia, Italy
| | - Aileen M Barnes
- Section on Heritable Disorders of Bone and Extracellular Matrix, NICHD, NIH, 20892 Bethesda, MD, USA
| | - Joan C Marini
- Section on Heritable Disorders of Bone and Extracellular Matrix, NICHD, NIH, 20892 Bethesda, MD, USA
| | - Antonella Forlino
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, 27100 Pavia, Italy
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6
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Scheiber AL, Wilkinson KJ, Suzuki A, Enomoto-Iwamoto M, Kaito T, Cheah KS, Iwamoto M, Leikin S, Otsuru S. 4PBA reduces growth deficiency in osteogenesis imperfecta by enhancing transition of hypertrophic chondrocytes to osteoblasts. JCI Insight 2022; 7:149636. [PMID: 34990412 PMCID: PMC8855815 DOI: 10.1172/jci.insight.149636] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 12/21/2021] [Indexed: 11/17/2022] Open
Abstract
Short stature is a major skeletal phenotype in osteogenesis imperfecta (OI), a genetic disorder mainly caused by mutations in genes encoding type I collagen. However, the underlying mechanism is poorly understood, and no effective treatment is available. In OI mice that carry a G610C mutation in COL1A2, we previously found that mature hypertrophic chondrocytes (HCs) are exposed to cell stress due to accumulation of misfolded mutant type I procollagen in the endoplasmic reticulum (ER). By fate mapping analysis of HCs in G610C OI mice, we found that HCs stagnate in the growth plate, inhibiting translocation of HC descendants to the trabecular area and their differentiation to osteoblasts. Treatment with 4-phenylbutyric acid (4PBA), a chemical chaperone, restored HC ER structure and rescued this inhibition, resulting in enhanced longitudinal bone growth in G610C OI mice. Interestingly, the effects of 4PBA on ER dilation were limited in osteoblasts, and the bone fragility was not ameliorated. These results highlight the importance of targeting HCs to treat growth deficiency in OI. Our findings demonstrate that HC dysfunction induced by ER disruption plays a critical role in the pathogenesis of OI growth deficiency, which lays the foundation for developing new therapies for OI.
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Affiliation(s)
- Amanda L Scheiber
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, United States of America
| | - Kevin J Wilkinson
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, United States of America
| | - Akiko Suzuki
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, United States of America
| | - Motomi Enomoto-Iwamoto
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, United States of America
| | - Takashi Kaito
- Department of Orthopaedic Surgery, Osaka University, Graduate School of Medicine, Osaka, Japan
| | - Kathryn Se Cheah
- School of Biomedical Sciences, University of Hong Kong, Hong Kong, China
| | - Masahiro Iwamoto
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, United States of America
| | - Sergey Leikin
- Section on Physical Biochemistry, Eunice Kennedy Shriver National Institute of Child Health & Human Developme, Bethesda, United States of America
| | - Satoru Otsuru
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, United States of America
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7
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Omar R, Malfait F, Van Agtmael T. Four decades in the making: Collagen III and mechanisms of vascular Ehlers Danlos Syndrome. Matrix Biol Plus 2021; 12:100090. [PMID: 34849481 PMCID: PMC8609142 DOI: 10.1016/j.mbplus.2021.100090] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 10/10/2021] [Accepted: 10/25/2021] [Indexed: 11/16/2022] Open
Abstract
Vascular Ehlers Danlos (vEDS) syndrome is a severe multi-systemic connective tissue disorder characterized by risk of dissection and rupture of the arteries, gastro-intestinal tract and gravid uterus. vEDS is caused by mutations in COL3A1, that encodes the alpha 1 chain of type III collagen, which is a major extracellular matrix component of the vasculature and hollow organs. The first causal mutations were identified in the 1980s but progress in our understanding of the pathomolecular mechanisms has been limited. Recently, the application of more refined animal models combined with global omics approaches has yielded important new insights both in terms of disease mechanisms and potential for therapeutic intervention. However, it is also becoming apparent that vEDS is a complex disorder in terms of its molecular disease mechanisms with a poorly understood allelic and mechanistic heterogeneity. In this brief review we will focus our attention on the disease mechanisms of COL3A1 mutations and vEDS, and recent progress in therapeutic approaches using animal models.
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Affiliation(s)
- Ramla Omar
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary & Life Sciences, University of Glasgow, G12 8QQ, UK
| | - Fransiska Malfait
- Centre for Medical Genetics, Ghent University Hospital, Belgium
- Department of Biomolecular Medicine, Ghent University, Belgium
| | - Tom Van Agtmael
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary & Life Sciences, University of Glasgow, G12 8QQ, UK
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8
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Gorrell L, Omari S, Makareeva E, Leikin S. Noncanonical ER-Golgi trafficking and autophagy of endogenous procollagen in osteoblasts. Cell Mol Life Sci 2021; 78:8283-8300. [PMID: 34779895 DOI: 10.1007/s00018-021-04017-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 10/01/2021] [Accepted: 10/27/2021] [Indexed: 01/05/2023]
Abstract
Secretion and quality control of large extracellular matrix proteins remain poorly understood and debated, particularly transport intermediates delivering folded proteins from the ER to Golgi and misfolded ones to lysosomes. Discrepancies between different studies are related to utilization of exogenous cargo, off-target effects of experimental conditions and cell manipulation, and identification of transport intermediates without tracing their origin and destination. To address these issues, here we imaged secretory and degradative trafficking of type I procollagen in live MC3T3 osteoblasts by replacing a region encoding N-propeptide in endogenous Col1a2 gDNA with GFP cDNA. We selected clones that produced the resulting fluorescent procollagen yet had normal expression of key osteoblast and ER/cell stress genes, normal procollagen folding, and normal deposition and mineralization of extracellular matrix. Live-cell imaging of these clones revealed ARF1-dependent transport intermediates, which had no COPII coat and delivered procollagen from ER exit sites (ERESs) to Golgi without stopping at ER-Golgi intermediate compartment (ERGIC). It also confirmed ERES microautophagy, i.e., lysosomes engulfing ERESs containing misfolded procollagen. Beyond validating these trafficking models for endogenous procollagen, we uncovered a probable cause of noncanonical cell stress response to procollagen misfolding. Recognized and retained only at ERESs, misfolded procollagen does not directly activate the canonical UPR, yet it disrupts the ER lumen by blocking normal secretory export from the ER.
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Affiliation(s)
- Laura Gorrell
- Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health, Bethesda, MD, 20892, USA.,Rensselaer Polytechnic Institute, Troy, NY, 12180, USA
| | - Shakib Omari
- Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health, Bethesda, MD, 20892, USA.,Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA, 92037, USA
| | - Elena Makareeva
- Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health, Bethesda, MD, 20892, USA
| | - Sergey Leikin
- Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health, Bethesda, MD, 20892, USA.
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9
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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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10
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Abstract
Collagen is the most abundant protein in mammals. A unique feature of collagen is its triple-helical structure formed by the Gly-Xaa-Yaa repeats. Three single chains of procollagen make a trimer, and the triple-helical structure is then folded in the endoplasmic reticulum (ER). This unique structure is essential for collagen's functions in vivo, including imparting bone strength, allowing signal transduction, and forming basement membranes. The triple-helical structure of procollagen is stabilized by posttranslational modifications and intermolecular interactions, but collagen is labile even at normal body temperature. Heat shock protein 47 (Hsp47) is a collagen-specific molecular chaperone residing in the ER that plays a pivotal role in collagen biosynthesis and quality control of procollagen in the ER. Mutations that affect the triple-helical structure or result in loss of Hsp47 activity cause the destabilization of procollagen, which is then degraded by autophagy. In this review, we present the current state of the field regarding quality control of procollagen.
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Affiliation(s)
- Shinya Ito
- Faculty of Life Sciences, Kyoto Sangyo University, Kyoto 603-8555, Japan;
| | - Kazuhiro Nagata
- Faculty of Life Sciences, Kyoto Sangyo University, Kyoto 603-8555, Japan; .,Institute for Protein Dynamics, Kyoto Sangyo University, Kyoto 603-8555, Japan; .,JT Biohistory Research Hall, Osaka, 569-1125, Japan
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11
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Takeyari S, Kubota T, Ohata Y, Fujiwara M, Kitaoka T, Taga Y, Mizuno K, Ozono K. 4-Phenylbutyric acid enhances the mineralization of osteogenesis imperfecta iPSC-derived osteoblasts. J Biol Chem 2021; 296:100027. [PMID: 33154166 PMCID: PMC7948972 DOI: 10.1074/jbc.ra120.014709] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Revised: 10/26/2020] [Accepted: 11/05/2020] [Indexed: 01/10/2023] Open
Abstract
Osteogenesis imperfecta (OI) is a heritable brittle bone disease mainly caused by mutations in the two type I collagen genes. Collagen synthesis is a complex process including trimer formation, glycosylation, secretion, extracellular matrix (ECM) formation, and mineralization. Using OI patient-derived fibroblasts and induced pluripotent stem cells (iPSCs), we investigated the effect of 4-phenylbutyric acid (4-PBA) on collagen synthesis to test its potential as a new treatment for OI. Endoplasmic reticulum (ER) retention of type I collagen was observed by immunofluorescence staining in OI patient-derived fibroblasts with glycine substitution and exon skipping mutations. Liquid chromatography-mass spectrometry analysis revealed excessive glycosylation of secreted type I collagen at the specific sites in OI cells. The misfolding of the type I collagen triple helix in the ECM was demonstrated by the incorporation of heat-dissociated collagen hybridizing peptide in OI cells. Type I collagen was produced excessively by OI fibroblasts with a glycine mutation, but this excessive production was normalized when OI fibroblasts were cultured on control fibroblast-derived ECM. We also found that mineralization was impaired in osteoblasts differentiated from OI iPSCs. In summary, treatment with 4-PBA normalizes the excessive production of type I collagen, reduces ER retention, partially improves misfolding of the type I collagen helix in ECM, and improves osteoblast mineralization. Thus, 4-PBA may improve not only ER retention, but also type I collagen synthesis and mineralization in human cells from OI patients.
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Affiliation(s)
- Shinji Takeyari
- Department of Pediatrics, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Takuo Kubota
- Department of Pediatrics, Osaka University Graduate School of Medicine, Suita, Osaka, Japan.
| | - Yasuhisa Ohata
- Department of Pediatrics, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Makoto Fujiwara
- Department of Pediatrics, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Taichi Kitaoka
- Department of Pediatrics, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Yuki Taga
- Nippi Research Institute of Biomatrix, Toride, Ibaraki, Japan
| | - Kazunori Mizuno
- Nippi Research Institute of Biomatrix, Toride, Ibaraki, Japan
| | - Keiichi Ozono
- Department of Pediatrics, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
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12
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Doan ND, Hosseini AS, Bikovtseva AA, Huang MS, DiChiara AS, Papa LJ, Koller A, Shoulders MD. Elucidation of proteostasis defects caused by osteogenesis imperfecta mutations in the collagen-α2(I) C-propeptide domain. J Biol Chem 2020; 295:9959-9973. [PMID: 32482890 DOI: 10.1074/jbc.ra120.014071] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Revised: 05/26/2020] [Indexed: 01/07/2023] Open
Abstract
Intracellular collagen assembly begins with the oxidative folding of ∼30-kDa C-terminal propeptide (C-Pro) domains. Folded C-Pro domains then template the formation of triple helices between appropriate partner strands. Numerous C-Pro missense variants that disrupt or delay triple-helix formation are known to cause disease, but our understanding of the specific proteostasis defects introduced by these variants remains immature. Moreover, it is unclear whether or not recognition and quality control of misfolded C-Pro domains is mediated by recognizing stalled assembly of triple-helical domains or by direct engagement of the C-Pro itself. Here, we integrate biochemical and cellular approaches to illuminate the proteostasis defects associated with osteogenesis imperfecta-causing mutations within the collagen-α2(I) C-Pro domain. We first show that "C-Pro-only" constructs recapitulate key aspects of the behavior of full-length Colα2(I) constructs. Of the variants studied, perhaps the most severe assembly defects are associated with C1163R C-Proα2(I), which is incapable of forming stable trimers and is retained within cells. We find that the presence or absence of an unassembled triple-helical domain is not the key feature driving cellular retention versus secretion. Rather, the proteostasis network directly engages the misfolded C-Pro domain itself to prevent secretion and initiate clearance. Using MS-based proteomics, we elucidate how the endoplasmic reticulum (ER) proteostasis network differentially engages misfolded C1163R C-Proα2(I) and targets it for ER-associated degradation. These results provide insights into collagen folding and quality control with the potential to inform the design of proteostasis network-targeted strategies for managing collagenopathies.
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Affiliation(s)
- Ngoc-Duc Doan
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Azade S Hosseini
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Agata A Bikovtseva
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Michelle S Huang
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Andrew S DiChiara
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Louis J Papa
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Antonius Koller
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Matthew D Shoulders
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
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13
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Khong ML, Li L, Solesio ME, Pavlov EV, Tanner JA. Inorganic polyphosphate controls cyclophilin B-mediated collagen folding in osteoblast-like cells. FEBS J 2020; 287:4500-4524. [PMID: 32056376 DOI: 10.1111/febs.15249] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 11/28/2019] [Accepted: 02/12/2020] [Indexed: 12/13/2022]
Abstract
Evidence is emerging that inorganic polyphosphate (polyP) is a fundamental molecule involved in a wide range of biological processes. In higher eukaryotes, polyP is abundant in osteoblasts but questions remain as to its functions. Here, we find that polyP is particularly enriched in endoplasmic reticulum (ER) where it colocalizes with cyclophilin B (CypB) using osteoblastic SaOS-2 model cell line. PolyP binds directly and specifically to CypB, inhibiting its peptidyl-prolyl cis-trans isomerase activity which is critical for collagen folding. PolyP sequestration by spermine and ER-specific polyP reduction by polyphosphatase expression in cells reduced collagen misfolding and confirmed that endogenous polyP acts as a molecular control of CypB-mediated collagen folding. We propose that polyP is a previously unrecognized critical regulator of protein homeostasis in ER.
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Affiliation(s)
- Mei Li Khong
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, China
| | - Lina Li
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, China
| | - Maria E Solesio
- Department of Basic Sciences and Craniofacial Biology, College of Dentistry, New York University, NY, USA
| | - Evgeny V Pavlov
- Department of Basic Sciences and Craniofacial Biology, College of Dentistry, New York University, NY, USA
| | - Julian A Tanner
- School of Biomedical Sciences, LKS Faculty of Medicine, The University of Hong Kong, Pokfulam, China
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14
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Hoop CL, Kemraj AP, Wang B, Gahlawat S, Godesky M, Zhu J, Warren HR, Case DA, Shreiber DI, Baum J. Molecular underpinnings of integrin binding to collagen-mimetic peptides containing vascular Ehlers-Danlos syndrome-associated substitutions. J Biol Chem 2019; 294:14442-14453. [PMID: 31406019 DOI: 10.1074/jbc.ra119.009685] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 08/06/2019] [Indexed: 11/06/2022] Open
Abstract
Collagens carry out critical extracellular matrix (ECM) functions by interacting with numerous cell receptors and ECM components. Single glycine substitutions in collagen III, which predominates in vascular walls, result in vascular Ehlers-Danlos syndrome (vEDS), leading to arterial, uterine, and intestinal rupture and an average life expectancy of <50 years. Collagen interactions with integrin α2β1 are vital for platelet adhesion and activation; however, how these interactions are impacted by vEDS-associated mutations and by specific amino acid substitutions is unclear. Here, we designed collagen-mimetic peptides (CMPs) with previously reported Gly → Xaa (Xaa = Ala, Arg, or Val) vEDS substitutions within a high-affinity integrin α2β1-binding motif, GROGER. We used these peptides to investigate, at atomic-level resolution, how these amino acid substitutions affect the collagen III-integrin α2β1 interaction. Using a multitiered approach combining biological adhesion assays, CD, NMR, and molecular dynamics (MD) simulations, we found that these substitutions differentially impede human mesenchymal stem cell spreading and integrin α2-inserted (α2I) domain binding to the CMPs and were associated with triple-helix destabilization. Although an Ala substitution locally destabilized hydrogen bonding and enhanced mobility, it did not significantly reduce the CMP-integrin interactions. MD simulations suggested that bulkier Gly → Xaa substitutions differentially disrupt the CMP-α2I interaction. The Gly → Arg substitution destabilized CMP-α2I side-chain interactions, and the Gly → Val change broke the essential Mg2+ coordination. The relationship between the loss of functional binding and the type of vEDS substitution provides a foundation for developing potential therapies for managing collagen disorders.
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Affiliation(s)
- Cody L Hoop
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854
| | - Allysa P Kemraj
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854
| | - Baifan Wang
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854
| | - Sonal Gahlawat
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854
| | - Madison Godesky
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854
| | - Jie Zhu
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854
| | - Haley R Warren
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854
| | - David A Case
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854
| | - David I Shreiber
- Department of Biomedical Engineering, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854
| | - Jean Baum
- Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, Piscataway, New Jersey 08854
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15
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Pickard A, Chang J, Alachkar N, Calverley B, Garva R, Arvan P, Meng QJ, Kadler KE. Preservation of circadian rhythms by the protein folding chaperone, BiP. FASEB J 2019; 33:7479-7489. [PMID: 30888851 PMCID: PMC6529331 DOI: 10.1096/fj.201802366rr] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Dysregulation of collagen synthesis is associated with disease progression in cancer and fibrosis. Collagen synthesis is coordinated with the circadian clock, which in cancer cells is, curiously, deregulated by endoplasmic reticulum (ER) stress. We hypothesized interplay between circadian rhythm, collagen synthesis, and ER stress in normal cells. Here we show that fibroblasts with ER stress lack circadian rhythms in gene expression upon clock-synchronizing time cues. Overexpression of binding immunoglobulin protein (BiP) or treatment with chemical chaperones strengthens the oscillation amplitude of circadian rhythms. The significance of these findings was explored in tendon, where we showed that BiP expression is ramped preemptively prior to a surge in collagen synthesis at night, thereby preventing protein misfolding and ER stress. In turn, this forestalls activation of the unfolded protein response in order for circadian rhythms to be maintained. Thus, targeting ER stress could be used to modulate circadian rhythm and restore collagen homeostasis in disease.—Pickard, A., Chang, J., Alachkar, N., Calverley, B., Garva, R., Arvan, P., Meng, Q.-J., Kadler, K. E. Preservation of circadian rhythms by the protein folding chaperone, BiP.
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Affiliation(s)
- Adam Pickard
- Wellcome Centre for Cell-Matrix Research, Faculty of Biology, Medicine, and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom
| | - Joan Chang
- Wellcome Centre for Cell-Matrix Research, Faculty of Biology, Medicine, and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom
| | - Nissrin Alachkar
- Wellcome Centre for Cell-Matrix Research, Faculty of Biology, Medicine, and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom.,School of Mathematics, Faculty of Science and Engineering, University of Manchester, Manchester, United Kingdom
| | - Ben Calverley
- Wellcome Centre for Cell-Matrix Research, Faculty of Biology, Medicine, and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom.,School of Mathematics, Faculty of Science and Engineering, University of Manchester, Manchester, United Kingdom
| | - Richa Garva
- Wellcome Centre for Cell-Matrix Research, Faculty of Biology, Medicine, and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom
| | - Peter Arvan
- Division of Metabolism, Endocrinology, and Diabetes, University of Michigan, Ann Arbor, Michigan, USA
| | - Qing-Jun Meng
- Wellcome Centre for Cell-Matrix Research, Faculty of Biology, Medicine, and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom
| | - Karl E Kadler
- Wellcome Centre for Cell-Matrix Research, Faculty of Biology, Medicine, and Health, Manchester Academic Health Science Centre, University of Manchester, Manchester, United Kingdom
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16
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Brommage R, Ohlsson C. High Fidelity of Mouse Models Mimicking Human Genetic Skeletal Disorders. Front Endocrinol (Lausanne) 2019; 10:934. [PMID: 32117046 PMCID: PMC7010808 DOI: 10.3389/fendo.2019.00934] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/02/2019] [Accepted: 12/23/2019] [Indexed: 12/24/2022] Open
Abstract
UNLABELLED The 2019 International Skeletal Dysplasia Society nosology update lists 441 genes for which mutations result in rare human skeletal disorders. These genes code for enzymes (33%), scaffolding proteins (18%), signal transduction proteins (16%), transcription factors (14%), cilia proteins (8%), extracellular matrix proteins (5%), and membrane transporters (4%). Skeletal disorders include aggrecanopathies, channelopathies, ciliopathies, cohesinopathies, laminopathies, linkeropathies, lysosomal storage diseases, protein-folding and RNA splicing defects, and ribosomopathies. With the goal of evaluating the ability of mouse models to mimic these human genetic skeletal disorders, a PubMed literature search identified 260 genes for which mutant mice were examined for skeletal phenotypes. These mouse models included spontaneous and ENU-induced mutants, global and conditional gene knockouts, and transgenic mice with gene over-expression or specific base-pair substitutions. The human X-linked gene ARSE and small nuclear RNA U4ATAC, a component of the minor spliceosome, do not have mouse homologs. Mouse skeletal phenotypes mimicking human skeletal disorders were observed in 249 of the 260 genes (96%) for which comparisons are possible. A supplemental table in spreadsheet format provides PubMed weblinks to representative publications of mutant mouse skeletal phenotypes. Mutations in 11 mouse genes (Ccn6, Cyp2r1, Flna, Galns, Gna13, Lemd3, Manba, Mnx1, Nsd1, Plod1, Smarcal1) do not result in similar skeletal phenotypes observed with mutations of the homologous human genes. These discrepancies can result from failure of mouse models to mimic the exact human gene mutations. There are no obvious commonalities among these 11 genes. Body BMD and/or radiologic dysmorphology phenotypes were successfully identified for 28 genes by the International Mouse Phenotyping Consortium (IMPC). Forward genetics using ENU mouse mutagenesis successfully identified 37 nosology gene phenotypes. Since many human genetic disorders involve hypomorphic, gain-of-function, dominant-negative and intronic mutations, future studies will undoubtedly utilize CRISPR/Cas9 technology to examine transgenic mice having genes modified to exactly mimic variant human sequences. Mutant mice will increasingly be employed for drug development studies designed to treat human genetic skeletal disorders. SIGNIFICANCE Great progress is being made identifying mutant genes responsible for human rare genetic skeletal disorders and mouse models for genes affecting bone mass, architecture, mineralization and strength. This review organizes data for 441 human genetic bone disorders with regard to heredity, gene function, molecular pathways, and fidelity of relevant mouse models to mimic the human skeletal disorders. PubMed weblinks to citations of 249 successful mouse models are provided.
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Affiliation(s)
- Robert Brommage
- Department of Internal Medicine and Clinical Nutrition, Centre for Bone and Arthritis Research, Institute of Medicine, The Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
- *Correspondence: Robert Brommage
| | - Claes Ohlsson
- Department of Internal Medicine and Clinical Nutrition, Centre for Bone and Arthritis Research, Institute of Medicine, The Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden
- Department of Drug Treatment, Sahlgrenska University Hospital, Gothenburg, Sweden
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17
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18
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Scheiber AL, Guess AJ, Kaito T, Abzug JM, Enomoto-Iwamoto M, Leikin S, Iwamoto M, Otsuru S. Endoplasmic reticulum stress is induced in growth plate hypertrophic chondrocytes in G610C mouse model of osteogenesis imperfecta. Biochem Biophys Res Commun 2018; 509:235-240. [PMID: 30579604 DOI: 10.1016/j.bbrc.2018.12.111] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 12/14/2018] [Indexed: 12/21/2022]
Abstract
Osteogenesis imperfecta (OI) is a hereditary bone disorder most commonly caused by autosomal dominant mutations in genes encoding type I collagen. In addition to bone fragility, patients suffer from impaired longitudinal bone growth. It has been demonstrated that in OI, an accumulation of mutated type I collagen in the endoplasmic reticulum (ER) induces ER stress in osteoblasts, causing osteoblast dysfunction leading to bone fragility. We hypothesize that ER stress is also induced in the growth plate where bone growth is initiated, and examined a mouse model of dominant OI that carries a G610C mutation in the procollagen α2 chain. The results demonstrated that G610C OI mice had significantly shorter long bones with growth plate abnormalities including elongated total height and hypertrophic zone. Moreover, we found that mature hypertrophic chondrocytes expressed type I collagen and ER dilation was more pronounced compared to wild type littermates. The results from in vitro chondrocyte cultures demonstrated that the maturation of G610C OI hypertrophic chondrocytes was significantly suppressed and ER stress related genes were upregulated. Given that the alteration of hypertrophic chondrocyte activity often causes dwarfism, our findings suggest that hypertrophic chondrocyte dysfunction induced by ER stress may be an underlying cause of growth deficiency in G610C OI mice.
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Affiliation(s)
- Amanda L Scheiber
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Adam J Guess
- Center for Childhood Cancer and Blood Diseases, The Research Institute at Nationwide Children's Hospital, Columbus, OH, 43205, USA
| | - Takashi Kaito
- Department of Orthopaedic Surgery, Osaka University, Graduate School of Medicine, Osaka, 565-0871, Japan
| | - Joshua M Abzug
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Motomi Enomoto-Iwamoto
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Sergey Leikin
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institute of Health, Bethesda, MD, 20892, USA
| | - Masahiro Iwamoto
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
| | - Satoru Otsuru
- Department of Orthopaedics, University of Maryland School of Medicine, Baltimore, MD, 21201, USA; Center for Childhood Cancer and Blood Diseases, The Research Institute at Nationwide Children's Hospital, Columbus, OH, 43205, USA.
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19
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Hang K, Ye C, Chen E, Zhang W, Xue D, Pan Z. Role of the heat shock protein family in bone metabolism. Cell Stress Chaperones 2018; 23:1153-1164. [PMID: 30187197 PMCID: PMC6237693 DOI: 10.1007/s12192-018-0932-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2018] [Revised: 08/11/2018] [Accepted: 08/15/2018] [Indexed: 12/17/2022] Open
Abstract
Heat shock proteins (HSPs) are a family of proteins produced by cells in response to exposure to stressful conditions. In addition to their role as chaperones, they also play an important role in the cardiovascular, immune, and other systems. Normal bone tissue is maintained by bone metabolism, particularly by the balance between osteoblasts and osteoclasts, which are physiologically regulated by multiple hormones and cytokines. In recent years, studies have reported the vital role of HSPs in bone metabolism. However, the conclusions remain largely controversial, and the exact mechanisms are still unclear, so a review and analyses of previous studies are of importance. This article reviews the current understanding of the roles and effects of HSPs on bone cells (osteoblasts, osteoclasts, and osteocytes), in relation to bone metabolism.
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Affiliation(s)
- Kai Hang
- Department of Orthopedic Surgery, the Second Affiliated Hospital, School of Medicine, Zhejiang University, No. 88, Jiefang Road, Hangzhou, 310009 China
- Orthopedics Research Institute, Zhejiang University, No. 88, Jiefang Road, Hangzhou, 310009 China
| | - Chenyi Ye
- Department of Orthopedic Surgery, the Second Affiliated Hospital, School of Medicine, Zhejiang University, No. 88, Jiefang Road, Hangzhou, 310009 China
- Orthopedics Research Institute, Zhejiang University, No. 88, Jiefang Road, Hangzhou, 310009 China
| | - Erman Chen
- Department of Orthopedic Surgery, the Second Affiliated Hospital, School of Medicine, Zhejiang University, No. 88, Jiefang Road, Hangzhou, 310009 China
- Orthopedics Research Institute, Zhejiang University, No. 88, Jiefang Road, Hangzhou, 310009 China
| | - Wei Zhang
- Department of Orthopedic Surgery, the Second Affiliated Hospital, School of Medicine, Zhejiang University, No. 88, Jiefang Road, Hangzhou, 310009 China
- Orthopedics Research Institute, Zhejiang University, No. 88, Jiefang Road, Hangzhou, 310009 China
| | - Deting Xue
- Department of Orthopedic Surgery, the Second Affiliated Hospital, School of Medicine, Zhejiang University, No. 88, Jiefang Road, Hangzhou, 310009 China
- Orthopedics Research Institute, Zhejiang University, No. 88, Jiefang Road, Hangzhou, 310009 China
| | - Zhijun Pan
- Department of Orthopedic Surgery, the Second Affiliated Hospital, School of Medicine, Zhejiang University, No. 88, Jiefang Road, Hangzhou, 310009 China
- Orthopedics Research Institute, Zhejiang University, No. 88, Jiefang Road, Hangzhou, 310009 China
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20
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Abstract
Type I collagen, a major component of bone, skin, and other connective tissues, is synthesized in the endoplasmic reticulum (ER) and passes through the secretory pathway. Rerouting of its procollagen precursor to a degradative pathway is crucial for reducing intracellular buildup in pathologies caused by defects in procollagen folding and trafficking. Here, we identify an autophagy pathway initiated at ER exit sites (ERESs). Procollagen proteins following this pathway accumulate at ERESs modified with ubiquitin, LC3, p62, and other autophagy machinery. Modified ERESs carrying procollagen are then engulfed by lysosomes through a microautophagy-like mechanism, not involving conventional, double-membrane autophagosomes. Procollagen homeostasis thus involves a noncanonical mode of autophagy initiated at ERESs, which might also be important in degradation of other secretory proteins. Type I collagen is the main component of bone matrix and other connective tissues. Rerouting of its procollagen precursor to a degradative pathway is crucial for osteoblast survival in pathologies involving excessive intracellular buildup of procollagen that is improperly folded and/or trafficked. What cellular mechanisms underlie this rerouting remains unclear. To study these mechanisms, we employed live-cell imaging and correlative light and electron microscopy (CLEM) to examine procollagen trafficking both in wild-type mouse osteoblasts and osteoblasts expressing a bone pathology-causing mutant procollagen. We found that although most procollagen molecules successfully trafficked through the secretory pathway in these cells, a subpopulation did not. The latter molecules appeared in numerous dispersed puncta colocalizing with COPII subunits, autophagy markers and ubiquitin machinery, with more puncta seen in mutant procollagen-expressing cells. Blocking endoplasmic reticulum exit site (ERES) formation suppressed the number of these puncta, suggesting they formed after procollagen entry into ERESs. The punctate structures containing procollagen, COPII, and autophagic markers did not move toward the Golgi but instead were relatively immobile. They appeared to be quickly engulfed by nearby lysosomes through a bafilomycin-insensitive pathway. CLEM and fluorescence recovery after photobleaching experiments suggested engulfment occurred through a noncanonical form of autophagy resembling microautophagy of ERESs. Overall, our findings reveal that a subset of procollagen molecules is directed toward lysosomal degradation through an autophagic pathway originating at ERESs, providing a mechanism to remove excess procollagen from cells.
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21
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Morello R. Osteogenesis imperfecta and therapeutics. Matrix Biol 2018; 71-72:294-312. [PMID: 29540309 PMCID: PMC6133774 DOI: 10.1016/j.matbio.2018.03.010] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 03/08/2018] [Accepted: 03/08/2018] [Indexed: 02/08/2023]
Abstract
Osteogenesis imperfecta, or brittle bone disease, is a congenital disease that primarily causes low bone mass and bone fractures but it can negatively affect other organs. It is usually inherited in an autosomal dominant fashion, although rarer recessive and X-chromosome-linked forms of the disease have been identified. In addition to type I collagen, mutations in a number of other genes, often involved in type I collagen synthesis or in the differentiation and function of osteoblasts, have been identified in the last several years. Seldom, the study of a rare disease has delivered such a wealth of new information that have helped our understanding of multiple processes involved in collagen synthesis and bone formation. In this short review I will describe the clinical features and the molecular genetics of the disease, but then focus on how OI dysregulates all aspects of extracellular matrix biology. I will conclude with a discussion about OI therapeutics.
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Affiliation(s)
- Roy Morello
- Department of Physiology & Biophysics, Orthopaedic Surgery, and Division of Genetics, University of Arkansas for Medical Sciences, Little Rock, AR, United States.
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22
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Abstract
Collagen is the dominant protein of the extracellular matrix. Its distinguishing feature is a three-stranded helix of great tensile strength. (2 S,4 R)-4-Hydroxyproline residues are essential for the stability of this triple helix. These residues arise from the post-translational modification of (2 S)-proline residues by collagen prolyl 4-hydroxylases (CP4Hs), which are members of the Fe(II)- and α-ketoglutarate (AKG)-dependent dioxygenase family. Here, we provide a framework for the inhibition of CP4Hs as the basis for treating fibrotic diseases and cancer metastasis. We begin with a summary of the structure and enzymatic reaction mechanism of CP4Hs. Then, we review the metal ions, metal chelators, mimetics of AKG and collagen strands, and natural products that are known to inhibit CP4Hs. Our focus is on inhibitors with potential utility in the clinic. We conclude with a prospectus for more effective inhibitors.
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Affiliation(s)
| | - Ronald T Raines
- Department of Chemistry , Massachusetts Institute of Technology , Cambridge , Massachusetts 02139 , United States
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23
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Makareeva E, Sun G, Mirigian LS, Mertz EL, Vera JC, Espinoza NA, Yang K, Chen D, Klein TE, Byers PH, Leikin S. Substitutions for arginine at position 780 in triple helical domain of the α1(I) chain alter folding of the type I procollagen molecule and cause osteogenesis imperfecta. PLoS One 2018; 13:e0200264. [PMID: 29990383 PMCID: PMC6039012 DOI: 10.1371/journal.pone.0200264] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 06/24/2018] [Indexed: 01/30/2023] Open
Abstract
OI is a clinically and genetically heterogeneous disorder characterized by bone fragility. More than 90% of patients are heterozygous for mutations in type I collagen genes, COL1A1 and COL1A2, and a common mutation is substitution for an obligatory glycine in the triple helical Gly-X-Y repeats. Few non-glycine substitutions in the triple helical domain have been reported; most result in Y-position substitutions of arginine by cysteine. Here, we investigated leucine and cysteine substitutions for one Y-position arginine, p.Arg958 (Arg780 in the triple helical domain) of proα1(I) chains that cause mild OI. We compared their effects with two substitutions for glycine located in close proximity. Like substitutions for glycine, those for arginine reduced the denaturation temperature of the whole molecule and caused asymmetric posttranslational overmodification of the chains. Circular dichroism and increased susceptibility to cleavage by MMP1, MMP2 and catalytic domain of MMP1 revealed significant destabilization of the triple helix near the collagenase cleavage site. On a cellular level, we observed slower triple helix folding and intracellular collagen retention, which disturbed the Endoplasmic Reticulum function and affected matrix deposition. Molecular dynamic modeling suggested that Arg780 substitutions disrupt the triple helix structure and folding by eliminating hydrogen bonds of arginine side chains, in addition to preventing HSP47 binding. The pathogenic effects of these non-glycine substitutions in bone are probably caused mostly by procollagen misfolding and its downstream effects.
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Affiliation(s)
- Elena Makareeva
- Section on Physical Biochemistry, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Guoli Sun
- Department of Pathology, University of Washington, Seattle, Washington, United States of America
| | - Lynn S. Mirigian
- Section on Physical Biochemistry, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Edward L. Mertz
- Section on Physical Biochemistry, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Juan C. Vera
- Section on Physical Biochemistry, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Nydea A. Espinoza
- Section on Physical Biochemistry, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Kathleen Yang
- Department of Pathology, University of Washington, Seattle, Washington, United States of America
| | - Diana Chen
- Department of Pathology, University of Washington, Seattle, Washington, United States of America
| | - Teri E. Klein
- Department of Genetics, Stanford University, Palo Alto, California, United States of America
| | - Peter H. Byers
- Department of Pathology, University of Washington, Seattle, Washington, United States of America
- Department of Medicine, Division of Medical Genetics, University of Washington, Seattle, Washington, United States of America
| | - Sergey Leikin
- Section on Physical Biochemistry, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, United States of America
- * E-mail:
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24
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Yu FY, Xie CQ, Sun JT, Peng W, Huang XW. Overexpressed miR-145 inhibits osteoclastogenesis in RANKL-induced bone marrow-derived macrophages and ovariectomized mice by regulation of Smad3. Life Sci 2018; 202:11-20. [PMID: 29577879 DOI: 10.1016/j.lfs.2018.03.042] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 03/12/2018] [Accepted: 03/21/2018] [Indexed: 12/21/2022]
Abstract
BACKGROUND MicroRNAs (miRs) play an important role in osteoclastogenesis. However, no study has investigated the underlying molecular mechanisms of miR-145 in this process. The purpose of the present study was to investigate the role of miR-145 and its post-transcriptional mechanism in the progression of osteoclast differentiation. METHODS Macrophage colony stimulating factor (M-CSF) and receptor activator of nuclear factor-kB ligand (RANKL) were used to induce osteoclastogenesis originated from bone marrow-derived macrophages (BMMs). Female C57BL/6J mice were divided into sham, OVX, OVX + NC-agomir and OVX + miR-145-agomir groups. Tartrate-resistant acid phosphatase (TRAP) staining was performed to identify osteoclasts in-vitro and in-vivo. The mRNA and protein levels in osteoclast and tibia were assayed by qRT-PCR and western blotting, respectively. RESULTS miR-145 expression was inhibited in RANKL-induced osteoclastogenesis, whereas overexpression of miR-145 attenuated it. We further found that Smad3 is a direct target gene of miR-145 by binding with its 3'-UTR. Overexpression of miR-145 significantly suppressed Smad3 mRNA and protein expression. In-vivo, miR-145 agomir treatment inhibited osteoclast activity in OVX mice by inhibiting Smad3 expression. CONCLUSION We provide the evidence that over-expression of miR-145 could inhibit osteoclast differentiation, at least partially, by decreasing Smad3 expression.
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Affiliation(s)
- Fang-Yuan Yu
- Department of Orthopedic, the 309th Hospital of PLA, Beijing 100091, China
| | - Cong-Qin Xie
- Department of Orthopedic, the 309th Hospital of PLA, Beijing 100091, China
| | - Ji-Tong Sun
- Department of Orthopedic, the 309th Hospital of PLA, Beijing 100091, China
| | - Wei Peng
- Department of Orthopedic, the 309th Hospital of PLA, Beijing 100091, China
| | - Xun-Wu Huang
- Department of Orthopedic, the 309th Hospital of PLA, Beijing 100091, China.
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25
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Omachi K, Kamura M, Teramoto K, Kojima H, Yokota T, Kaseda S, Kuwazuru J, Fukuda R, Koyama K, Matsuyama S, Motomura K, Shuto T, Suico MA, Kai H. A Split-Luciferase-Based Trimer Formation Assay as a High-throughput Screening Platform for Therapeutics in Alport Syndrome. Cell Chem Biol 2018. [PMID: 29526710 DOI: 10.1016/j.chembiol.2018.02.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Alport syndrome is a hereditary glomerular disease caused by mutation in type IV collagen α3-α5 chains (α3-α5(IV)), which disrupts trimerization, leading to glomerular basement membrane degeneration. Correcting the trimerization of α3/α4/α5 chain is a feasible therapeutic approach, but is hindered by lack of information on the regulation of intracellular α(IV) chain and the absence of high-throughput screening (HTS) platforms to assess α345(IV) trimer formation. Here, we developed sets of split NanoLuc-fusion α345(IV) proteins to monitor α345(IV) trimerization of wild-type and clinically associated mutant α5(IV). The α345(IV) trimer assay, which satisfied the acceptance criteria for HTS, enabled the characterization of intracellular- and secretion-dependent defects of mutant α5(IV). Small interfering RNA-based and chemical screening targeting the ER identified several chemical chaperones that have potential to promote α345(IV) trimer formation. This split luciferase-based trimer formation assay is a functional HTS platform that realizes the feasibility of targeting α345(IV) trimers to treat Alport syndrome.
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Affiliation(s)
- Kohei Omachi
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan; Program for Leading Graduate School "HIGO (Health Life Science: Interdisciplinary and Glocal Oriented) Program", Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Misato Kamura
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan; Program for Leading Graduate School "HIGO (Health Life Science: Interdisciplinary and Glocal Oriented) Program", Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Keisuke Teramoto
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan; Program for Leading Graduate School "HIGO (Health Life Science: Interdisciplinary and Glocal Oriented) Program", Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Haruka Kojima
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Tsubasa Yokota
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Shota Kaseda
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan; Program for Leading Graduate School "HIGO (Health Life Science: Interdisciplinary and Glocal Oriented) Program", Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Jun Kuwazuru
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Ryosuke Fukuda
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Kosuke Koyama
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Shingo Matsuyama
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Keishi Motomura
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Tsuyoshi Shuto
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan
| | - Mary Ann Suico
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan.
| | - Hirofumi Kai
- Department of Molecular Medicine, Graduate School of Pharmaceutical Sciences, Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan; Program for Leading Graduate School "HIGO (Health Life Science: Interdisciplinary and Glocal Oriented) Program", Kumamoto University, 5-1 Oe-honmachi, Chuo-ku, Kumamoto City 862-0973, Kumamoto, Japan.
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Besio R, Iula G, Garibaldi N, Cipolla L, Sabbioneda S, Biggiogera M, Marini JC, Rossi A, Forlino A. 4-PBA ameliorates cellular homeostasis in fibroblasts from osteogenesis imperfecta patients by enhancing autophagy and stimulating protein secretion. Biochim Biophys Acta Mol Basis Dis 2018; 1864:1642-1652. [PMID: 29432813 PMCID: PMC5908783 DOI: 10.1016/j.bbadis.2018.02.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 02/06/2018] [Accepted: 02/08/2018] [Indexed: 12/11/2022]
Abstract
The clinical phenotype in osteogenesis imperfecta (OI) is attributed to the dominant negative function of mutant type I collagen molecules in the extracellular matrix, by altering its structure and function. Intracellular retention of mutant collagen has also been reported, but its effect on cellular homeostasis is less characterized. Using OI patient fibroblasts carrying mutations in the α1(I) and α2(I) chains we demonstrate that retained collagen molecules are responsible for endoplasmic reticulum (ER) enlargement and activation of the unfolded protein response (UPR) mainly through the eukaryotic translation initiation factor 2 alpha kinase 3 (PERK) branch. Cells carrying α1(I) mutations upregulate autophagy, while cells with α2(I) mutations only occasionally activate the autodegradative response. Despite the autophagy activation to face stress conditions, apoptosis occurs in all mutant fibroblasts. To reduce cellular stress, mutant fibroblasts were treated with the FDA-approved chemical chaperone 4-phenylbutyric acid. The drug rescues cell death by modulating UPR activation thanks to both its chaperone and histone deacetylase inhibitor abilities. As chaperone it increases general cellular protein secretion in all patients' cells as well as collagen secretion in cells with the most C-terminal mutation. As histone deacetylase inhibitor it enhances the expression of the autophagic gene Atg5 with a consequent stimulation of autophagy. These results demonstrate that the cellular response to ER stress can be a relevant target to ameliorate OI cell homeostasis.
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Affiliation(s)
- Roberta Besio
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Pavia 27100, Italy.
| | - Giusy Iula
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Pavia 27100, Italy.
| | - Nadia Garibaldi
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Pavia 27100, Italy.
| | - Lina Cipolla
- Istituto di Genetica Molecolare, Consiglio Nazionale delle Ricerche, Pavia 27100, Italy.
| | - Simone Sabbioneda
- Istituto di Genetica Molecolare, Consiglio Nazionale delle Ricerche, Pavia 27100, Italy.
| | - Marco Biggiogera
- Department of Biology and Biotechnology, University of Pavia, 27100 Pavia, Italy.
| | - Joan C Marini
- Bone and Extracellular Matrix Branch, NICHD, National Institute of Health, Bethesda, MD 20892, USA.
| | - Antonio Rossi
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Pavia 27100, Italy.
| | - Antonella Forlino
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Pavia 27100, Italy.
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27
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Gioia R, Tonelli F, Ceppi I, Biggiogera M, Leikin S, Fisher S, Tenedini E, Yorgan TA, Schinke T, Tian K, Schwartz JM, Forte F, Wagener R, Villani S, Rossi A, Forlino A. The chaperone activity of 4PBA ameliorates the skeletal phenotype of Chihuahua, a zebrafish model for dominant osteogenesis imperfecta. Hum Mol Genet 2018; 26:2897-2911. [PMID: 28475764 PMCID: PMC5886106 DOI: 10.1093/hmg/ddx171] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 05/02/2017] [Indexed: 12/21/2022] Open
Abstract
Classical osteogenesis imperfecta (OI) is a bone disease caused by type I collagen mutations and characterized by bone fragility, frequent fractures in absence of trauma and growth deficiency. No definitive cure is available for OI and to develop novel drug therapies, taking advantage of a repositioning strategy, the small teleost zebrafish (Danio rerio) is a particularly appealing model. Its small size, high proliferative rate, embryo transparency and small amount of drug required make zebrafish the model of choice for drug screening studies, when a valid disease model is available. We performed a deep characterization of the zebrafish mutant Chihuahua, that carries a G574D (p.G736D) substitution in the α1 chain of type I collagen. We successfully validated it as a model for classical OI. Growth of mutants was delayed compared with WT. X-ray, µCT, alizarin red/alcian blue and calcein staining revealed severe skeletal deformity, presence of fractures and delayed mineralization. Type I collagen extracted from different tissues showed abnormal electrophoretic migration and low melting temperature. The presence of endoplasmic reticulum (ER) enlargement due to mutant collagen retention in osteoblasts and fibroblasts of mutant fish was shown by electron and confocal microscopy. Two chemical chaperones, 4PBA and TUDCA, were used to ameliorate the cellular stress and indeed 4PBA ameliorated bone mineralization in larvae and skeletal deformities in adult, mainly acting on reducing ER cisternae size and favoring collagen secretion. In conclusion, our data demonstrated that ER stress is a novel target to ameliorate OI phenotype; chemical chaperones such as 4PBA may be, alone or in combination, a new class of molecules to be further investigated for OI treatment.
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Affiliation(s)
- Roberta Gioia
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Pavia, Italy
| | - Francesca Tonelli
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Pavia, Italy
| | - Ilaria Ceppi
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Pavia, Italy
| | - Marco Biggiogera
- Department of Biology and Biotechnology, University of Pavia, Pavia, Italy
| | - Sergey Leikin
- Section on Physical Biochemistry, Eunice Kennedy Shriver NICHD, NIH, Bethesda, MD, USA
| | - Shannon Fisher
- Department of Pharmacology & Experimental Therapeutics, Boston University School of Medicine, Boston, MA, USA
| | - Elena Tenedini
- Center for Genome Research, Department of Medical and Surgical Sciences, University of Modena and Reggio Emilia, Modena, Italy
| | - Timur A Yorgan
- Institute of Osteology and Biomechanic, Center for Experimental Medicine, University of Hamburg, Hamburg, Germany
| | - Thorsten Schinke
- Institute of Osteology and Biomechanic, Center for Experimental Medicine, University of Hamburg, Hamburg, Germany
| | - Kun Tian
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Jean-Marc Schwartz
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Fabiana Forte
- Medical Faculty, Center for Biochemistry, Center for Molecular Medicine, University of Cologne, Cologne, Germany
| | - Raimund Wagener
- Medical Faculty, Center for Biochemistry, Center for Molecular Medicine, University of Cologne, Cologne, Germany
| | - Simona Villani
- Department of Public Health and Experimental and Forensic Medicine, Unit of Biostatistics and Clinical Epidemiology, University of Pavia, Pavia, Italy
| | - Antonio Rossi
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Pavia, Italy
| | - Antonella Forlino
- Department of Molecular Medicine, Biochemistry Unit, University of Pavia, Pavia, Italy
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28
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Ito S, Ogawa K, Takeuchi K, Takagi M, Yoshida M, Hirokawa T, Hirayama S, Shin-Ya K, Shimada I, Doi T, Goshima N, Natsume T, Nagata K. A small-molecule compound inhibits a collagen-specific molecular chaperone and could represent a potential remedy for fibrosis. J Biol Chem 2017; 292:20076-20085. [PMID: 29025875 DOI: 10.1074/jbc.m117.815936] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2017] [Revised: 10/10/2017] [Indexed: 11/06/2022] Open
Abstract
Fibrosis can disrupt tissue structure and integrity and impair organ function. Fibrosis is characterized by abnormal collagen accumulation in the extracellular matrix. Pharmacological inhibition of collagen secretion therefore represents a promising strategy for the management of fibrotic disorders, such as liver and lung fibrosis. Hsp47 is an endoplasmic reticulum (ER)-resident collagen-specific molecular chaperone essential for correct folding of procollagen in the ER. Genetic deletion of Hsp47 or inhibition of its interaction with procollagen interferes with procollagen triple helix production, which vastly reduces procollagen secretion from fibroblasts. Thus, Hsp47 could be a potential and promising target for the management of fibrosis. In this study, we screened small-molecule compounds that inhibit the interaction of Hsp47 with collagen from chemical libraries using surface plasmon resonance (BIAcore), and we found a molecule AK778 and its cleavage product Col003 competitively inhibited the interaction and caused the inhibition of collagen secretion by destabilizing the collagen triple helix. Structural information obtained with NMR analysis revealed that Col003 competitively binds to the collagen-binding site on Hsp47. We propose that these structural insights could provide a basis for designing more effective therapeutic drugs for managing fibrosis.
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Affiliation(s)
- Shinya Ito
- Institute for Protein Dynamics, Kyoto Sangyo University, Kyoto 603-8555; Department of Molecular and Cellular Biology, Institute for Frontier Medical Sciences, Kyoto University, Kyoto 606-8507
| | - Koji Ogawa
- National Institute of Advanced Industrial Science and Technology (AIST), Tokyo 135-0064
| | - Koh Takeuchi
- National Institute of Advanced Industrial Science and Technology (AIST), Tokyo 135-0064
| | - Motoki Takagi
- Japan Biological Informatics Consortium (JBIC), Tokyo 135-0064
| | - Masahito Yoshida
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai 980-8578
| | - Takatsugu Hirokawa
- National Institute of Advanced Industrial Science and Technology (AIST), Tokyo 135-0064
| | | | - Kazuo Shin-Ya
- National Institute of Advanced Industrial Science and Technology (AIST), Tokyo 135-0064
| | - Ichio Shimada
- Division of Physical Chemistry, Graduate School of Pharmaceutical Sciences, University of Tokyo, Tokyo 113-0033
| | - Takayuki Doi
- Graduate School of Pharmaceutical Sciences, Tohoku University, Sendai 980-8578
| | - Naoki Goshima
- National Institute of Advanced Industrial Science and Technology (AIST), Tokyo 135-0064
| | - Tohru Natsume
- National Institute of Advanced Industrial Science and Technology (AIST), Tokyo 135-0064.
| | - Kazuhiro Nagata
- Institute for Protein Dynamics, Kyoto Sangyo University, Kyoto 603-8555; Department of Molecular Biosciences, Faculty of Life Sciences, Kyoto Sangyo University, Kyoto 603-8555, Japan; Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency, Kyoto 603-8555, Japan.
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29
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Ishikawa Y, Holden P, Bächinger HP. Heat shock protein 47 and 65-kDa FK506-binding protein weakly but synergistically interact during collagen folding in the endoplasmic reticulum. J Biol Chem 2017; 292:17216-17224. [PMID: 28860186 DOI: 10.1074/jbc.m117.802298] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 08/18/2017] [Indexed: 12/21/2022] Open
Abstract
Collagen is the most abundant protein in the extracellular matrix in humans and is critical to the integrity and function of many musculoskeletal tissues. A molecular ensemble comprising more than 20 molecules is involved in collagen biosynthesis in the rough endoplasmic reticulum. Two proteins, heat shock protein 47 (Hsp47/SERPINH1) and 65-kDa FK506-binding protein (FKBP65/FKBP10), have been shown to play important roles in this ensemble. In humans, autosomal recessive mutations in both genes cause similar osteogenesis imperfecta phenotypes. Whereas it has been proposed that Hsp47 and FKBP65 interact in the rough endoplasmic reticulum, there is neither clear evidence for this interaction nor any data regarding their binding affinities for each other. In this study using purified endogenous proteins, we examined the interaction between Hsp47, FKBP65, and collagen and also determined their binding affinities and functions in vitro Hsp47 and FKBP65 show a direct but weak interaction, and FKBP65 prefers to interact with Hsp47 rather than type I collagen. Our results suggest that a weak interaction between Hsp47 and FKBP65 confers mutual molecular stability and also allows for a synergistic effect during collagen folding. We also propose that Hsp47 likely acts as a hub molecule during collagen folding and secretion by directing other molecules to reach their target sites on collagens. Our findings may explain why osteogenesis imperfecta-causing mutations in both genes result in similar phenotypes.
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Affiliation(s)
- Yoshihiro Ishikawa
- From the Department of Biochemistry and Molecular Biology, Oregon Health and Science University and Shriners Hospital for Children, Research Department, Portland, Oregon 97239
| | - Paul Holden
- From the Department of Biochemistry and Molecular Biology, Oregon Health and Science University and Shriners Hospital for Children, Research Department, Portland, Oregon 97239
| | - Hans Peter Bächinger
- From the Department of Biochemistry and Molecular Biology, Oregon Health and Science University and Shriners Hospital for Children, Research Department, Portland, Oregon 97239
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30
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Hughes A, Oxford AE, Tawara K, Jorcyk CL, Oxford JT. Endoplasmic Reticulum Stress and Unfolded Protein Response in Cartilage Pathophysiology; Contributing Factors to Apoptosis and Osteoarthritis. Int J Mol Sci 2017; 18:ijms18030665. [PMID: 28335520 PMCID: PMC5372677 DOI: 10.3390/ijms18030665] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2017] [Revised: 03/15/2017] [Accepted: 03/16/2017] [Indexed: 12/11/2022] Open
Abstract
Chondrocytes of the growth plate undergo apoptosis during the process of endochondral ossification, as well as during the progression of osteoarthritis. Although the regulation of this process is not completely understood, alterations in the precisely orchestrated programmed cell death during development can have catastrophic results, as exemplified by several chondrodystrophies which are frequently accompanied by early onset osteoarthritis. Understanding the mechanisms that underlie chondrocyte apoptosis during endochondral ossification in the growth plate has the potential to impact the development of therapeutic applications for chondrodystrophies and associated early onset osteoarthritis. In recent years, several chondrodysplasias and collagenopathies have been recognized as protein-folding diseases that lead to endoplasmic reticulum stress, endoplasmic reticulum associated degradation, and the unfolded protein response. Under conditions of prolonged endoplasmic reticulum stress in which the protein folding load outweighs the folding capacity of the endoplasmic reticulum, cellular dysfunction and death often occur. However, unfolded protein response (UPR) signaling is also required for the normal maturation of chondrocytes and osteoblasts. Understanding how UPR signaling may contribute to cartilage pathophysiology is an essential step toward therapeutic modulation of skeletal disorders that lead to osteoarthritis.
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Affiliation(s)
- Alexandria Hughes
- Department of Biological Sciences, Boise State University, Boise, ID 83725, USA.
- Biomolecular Research Center, Boise State University, Boise, ID 83725, USA.
| | - Alexandra E Oxford
- Department of Biological Sciences, Boise State University, Boise, ID 83725, USA.
- Biomolecular Research Center, Boise State University, Boise, ID 83725, USA.
| | - Ken Tawara
- Biomolecular Sciences Graduate Program, Boise State University, Boise, ID 83725, USA.
- Biomolecular Research Center, Boise State University, Boise, ID 83725, USA.
| | - Cheryl L Jorcyk
- Department of Biological Sciences, Boise State University, Boise, ID 83725, USA.
- Biomolecular Sciences Graduate Program, Boise State University, Boise, ID 83725, USA.
- Biomolecular Research Center, Boise State University, Boise, ID 83725, USA.
| | - Julia Thom Oxford
- Department of Biological Sciences, Boise State University, Boise, ID 83725, USA.
- Biomolecular Sciences Graduate Program, Boise State University, Boise, ID 83725, USA.
- Biomolecular Research Center, Boise State University, Boise, ID 83725, USA.
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31
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Decreasing maternal myostatin programs adult offspring bone strength in a mouse model of osteogenesis imperfecta. Proc Natl Acad Sci U S A 2016; 113:13522-13527. [PMID: 27821779 DOI: 10.1073/pnas.1607644113] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
During fetal development, the uterine environment can have effects on offspring bone architecture and integrity that persist into adulthood; however, the biochemical and molecular mechanisms remain unknown. Myostatin is a negative regulator of muscle mass. Parental myostatin deficiency (Mstntm1Sjl/+) increases muscle mass in wild-type offspring, suggesting an intrauterine programming effect. Here, we hypothesized that Mstntm1Sjl/+ dams would also confer increased bone strength. In wild-type offspring, maternal myostatin deficiency altered fetal growth and calvarial collagen content of newborn mice and conferred a lasting impact on bone geometry and biomechanical integrity of offspring at 4 mo of age, the age of peak bone mass. Second, we sought to apply maternal myostatin deficiency to a mouse model with osteogenesis imperfecta (Col1a2oim), a heritable connective tissue disorder caused by abnormalities in the structure and/or synthesis of type I collagen. Femora of male Col1a2oim/+ offspring from natural mating of Mstntm1Sjl/+ dams to Col1a2oim/+sires had a 15% increase in torsional ultimate strength, a 29% increase in tensile strength, and a 24% increase in energy to failure compared with age, sex, and genotype-matched offspring from natural mating of Col1a2oim/+ dams to Col1a2oim/+ sires. Finally, increased bone biomechanical strength of Col1a2oim/+ offspring that had been transferred into Mstntm1Sjl/+ dams as blastocysts demonstrated that the effects of maternal myostatin deficiency were conferred by the postimplantation environment. Thus, targeting the gestational environment, and specifically prenatal myostatin pathways, provides a potential therapeutic window and an approach for treating osteogenesis imperfecta.
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32
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Marom R, Lee YC, Grafe I, Lee B. Pharmacological and biological therapeutic strategies for osteogenesis imperfecta. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2016; 172:367-383. [PMID: 27813341 DOI: 10.1002/ajmg.c.31532] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Osteogenesis imperfecta (OI) is a connective tissue disorder characterized by bone fragility, low bone mass, and bone deformities. The majority of cases are caused by autosomal dominant pathogenic variants in the COL1A1 and COL1A2 genes that encode type I collagen, the major component of the bone matrix. The remaining cases are caused by autosomal recessively or dominantly inherited mutations in genes that are involved in the post-translational modification of type I collagen, act as type I collagen chaperones, or are members of the signaling pathways that regulate bone homeostasis. The main goals of treatment in OI are to decrease fracture incidence, relieve bone pain, and promote mobility and growth. This requires a multi-disciplinary approach, utilizing pharmacological interventions, physical therapy, orthopedic surgery, and monitoring nutrition with appropriate calcium and vitamin D supplementation. Bisphosphonate therapy, which has become the mainstay of treatment in OI, has proven beneficial in increasing bone mass, and to some extent reducing fracture risk. However, the response to treatment is not as robust as is seen in osteoporosis, and it seems less effective in certain types of OI, and in adult OI patients as compared to most pediatric cases. New pharmacological treatments are currently being developed, including anti-resorptive agents, anabolic treatment, and gene- and cell-therapy approaches. These therapies are under different stages of investigation from the bench-side, to pre-clinical and clinical trials. In this review, we will summarize the recent findings regarding the pharmacological and biological strategies for the treatment of patients with OI. © 2016 Wiley Periodicals, Inc.
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33
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Yigit S, Yu H, An B, Hamaia S, Farndale RW, Kaplan DL, Lin YS, Brodsky B. Mapping the Effect of Gly Mutations in Collagen on α2β1 Integrin Binding. J Biol Chem 2016; 291:19196-207. [PMID: 27432884 PMCID: PMC5009287 DOI: 10.1074/jbc.m116.726182] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Indexed: 11/06/2022] Open
Abstract
The replacement of one Gly in the essential repeating tripeptide sequence of the type I collagen triple helix results in the dominant hereditary bone disorder osteogenesis imperfecta. The mechanism leading to pathology likely involves misfolding and autophagy, although it has been hypothesized that some mutations interfere with known collagen interactions. Here, the effect of Gly replacements within and nearby the integrin binding GFPGER sequence was investigated using a recombinant bacterial collagen system. When a six-triplet human type I collagen sequence containing GFPGER was introduced into a bacterial collagen-like protein, this chimeric protein bound to integrin. Constructs with Gly to Ser substitutions within and nearby the inserted human sequence still formed a trypsin-resistant triple helix, suggesting a small local conformational perturbation. Gly to Ser mutations within the two Gly residues in the essential GFPGER sequence prevented integrin binding and cell attachment as predicted from molecular dynamics studies of the complex. Replacement of Gly residues C-terminal to GFPGER did not affect integrin binding. In contrast, Gly replacements N-terminal to the GFPGER sequence, up to four triplets away, decreased integrin binding and cell adhesion. This pattern suggests either an involvement of the triplets N-terminal to GFPGER in initial binding or a propagation of the perturbation of the triple helix C-terminal to a mutation site. The asymmetry in biological consequences relative to the mutation site may relate to the observed pattern of osteogenesis imperfecta mutations near the integrin binding site.
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Affiliation(s)
- Sezin Yigit
- From the Departments of Biomedical Engineering and Chemistry, Tufts University, Medford, Massachusetts 02155 and
| | - Hongtao Yu
- From the Departments of Biomedical Engineering and Chemistry, Tufts University, Medford, Massachusetts 02155 and
| | - Bo An
- From the Departments of Biomedical Engineering and
| | - Samir Hamaia
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, United Kingdom
| | - Richard W Farndale
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, United Kingdom
| | | | - Yu-Shan Lin
- Chemistry, Tufts University, Medford, Massachusetts 02155 and
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Mirigian LS, Makareeva E, Mertz EL, Omari S, Roberts-Pilgrim AM, Oestreich AK, Phillips CL, Leikin S. Osteoblast Malfunction Caused by Cell Stress Response to Procollagen Misfolding in α2(I)-G610C Mouse Model of Osteogenesis Imperfecta. J Bone Miner Res 2016; 31:1608-1616. [PMID: 26925839 PMCID: PMC5061462 DOI: 10.1002/jbmr.2824] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Revised: 02/22/2016] [Accepted: 02/26/2016] [Indexed: 12/26/2022]
Abstract
Glycine (Gly) substitutions in collagen Gly-X-Y repeats disrupt folding of type I procollagen triple helix and cause severe bone fragility and malformations (osteogenesis imperfecta [OI]). However, these mutations do not elicit the expected endoplasmic reticulum (ER) stress response, in contrast to other protein-folding diseases. Thus, it has remained unclear whether cell stress and osteoblast malfunction contribute to the bone pathology caused by Gly substitutions. Here we used a mouse with a Gly610 to cysteine (Cys) substitution in the procollagen α2(I) chain to show that misfolded procollagen accumulation in the ER leads to an unusual form of cell stress, which is neither a conventional unfolded protein response (UPR) nor ER overload. Despite pronounced ER dilation, there is no upregulation of binding immunoglobulin protein (BIP) expected in the UPR and no activation of NF-κB signaling expected in the ER overload. Altered expression of ER chaperones αB crystalline and HSP47, phosphorylation of EIF2α, activation of autophagy, upregulation of general stress response protein CHOP, and osteoblast malfunction reveal some other adaptive response to the ER disruption. We show how this response alters differentiation and function of osteoblasts in culture and in vivo. We demonstrate that bone matrix deposition by cultured osteoblasts is rescued by activation of misfolded procollagen autophagy, suggesting a new therapeutic strategy for OI. © 2016 American Society for Bone and Mineral Research.
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Affiliation(s)
- Lynn S Mirigian
- Section on Physical Biochemistry, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health, Bethesda, MD 20892.,Department of Cell Biology, University of Texas Medical Branch, Galveston, TX 77555
| | - Elena Makareeva
- Section on Physical Biochemistry, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health, Bethesda, MD 20892
| | - Edward L Mertz
- Section on Physical Biochemistry, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health, Bethesda, MD 20892
| | - Shakib Omari
- Section on Physical Biochemistry, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health, Bethesda, MD 20892
| | - Anna M Roberts-Pilgrim
- Section on Physical Biochemistry, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health, Bethesda, MD 20892
| | - Arin K Oestreich
- Division of Biological Sciences, University of Missouri, Columbia, MO 65211
| | | | - Sergey Leikin
- Section on Physical Biochemistry, Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD), National Institutes of Health, Bethesda, MD 20892
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Fratzl-Zelman N, Misof BM, Roschger P, Klaushofer K. Classification of osteogenesis imperfecta. Wien Med Wochenschr 2015. [PMID: 26208476 DOI: 10.1007/s10354-015-0368-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Osteogenesis imperfecta (OI) is an extremely heterogeneous group of heritable connective tissue disorders. Most of the affected patients carry autosomal dominant mutations in the genes encoding for collagen type I, the most abundant protein of the bone extracellular matrix. The resulting phenotypes are extremely broad and have been classified by Sillence and colleagues into four groups according to clinical, radiological and genetic criteria.More recently, proteins have been described that interact directly or indirectly with collagen biosynthesis and their deficiency result in rare forms of mostly autosomal recessive OI sharing phenotypic features of 'classical' types but lacking primary defects in type I collagen. Consequently the Sillence classification has been gradually expanded to include novel forms based on the underlying mutations. The goal of this article is to revisit the actual OI classification and to outline current approaches in categorizing the disorder.
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Affiliation(s)
- Nadja Fratzl-Zelman
- Ludwig Boltzmann Institute of Osteology, Hanusch Hospital of WGKK and AUVA Trauma Centre Meidling, 1st Med. Dept. Hanusch Hospital, Heinrich Collin Str. 30, 1140, Vienna, Austria,
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Lindert U, Weis MA, Rai J, Seeliger F, Hausser I, Leeb T, Eyre D, Rohrbach M, Giunta C. Molecular Consequences of the SERPINH1/HSP47 Mutation in the Dachshund Natural Model of Osteogenesis Imperfecta. J Biol Chem 2015; 290:17679-17689. [PMID: 26004778 DOI: 10.1074/jbc.m115.661025] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Indexed: 01/24/2023] Open
Abstract
Osteogenesis imperfecta (OI) is a heritable connective tissue disease characterized by bone fragility and increased risk of fractures. Up to now, mutations in at least 18 genes have been associated with dominant and recessive forms of OI that affect the production or post-translational processing of procollagen or alter bone homeostasis. Among those, SERPINH1 encoding heat shock protein 47 (HSP47), a chaperone exclusive for collagen folding in the ER, was identified to cause a severe form of OI in dachshunds (L326P) as well as in humans (one single case with a L78P mutation). To elucidate the disease mechanism underlying OI in the dog model, we applied a range of biochemical assays to mutant and control skin fibroblasts as well as on bone samples. These experiments revealed that type I collagen synthesized by mutant cells had decreased electrophoretic mobility. Procollagen was retained intracellularly with concomitant dilation of ER cisternae and activation of the ER stress response markers GRP78 and phospho-eIF2α, thus suggesting a defect in procollagen processing. In line with the migration shift detected on SDS-PAGE of cell culture collagen, extracts of bone collagen from the OI dog showed a similar mobility shift, and on tandem mass spectrometry, the chains were post-translationally overmodified. The bone collagen had a higher content of pyridinoline than control dog bone. We conclude that the SERPINH1 mutation in this naturally occurring model of OI impairs how HSP47 acts as a chaperone in the ER. This results in abnormal post-translational modification and cross-linking of the bone collagen.
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Affiliation(s)
- Uschi Lindert
- Division of Metabolism, Connective Tissue Unit, University Children's Hospital Zurich, Children's Research Center, 8032 Zurich, Switzerland
| | - Mary Ann Weis
- Department of Orthopaedics and Sports Medicine, University of Washington, Seattle, Washington 98195
| | - Jyoti Rai
- Department of Orthopaedics and Sports Medicine, University of Washington, Seattle, Washington 98195
| | - Frank Seeliger
- AstraZeneca, Drug Safety and Metabolism, 431 83 Mölndal, Sweden
| | - Ingrid Hausser
- Institute of Pathology, University Hospital Heidelberg and Electron Microscopy Core Facility, Heidelberg University, 69120 Heidelberg, Germany
| | - Tosso Leeb
- Institute of Genetics, Vetsuisse Faculty, University of Bern, CH-3001 Bern, Switzerland
| | - David Eyre
- Department of Orthopaedics and Sports Medicine, University of Washington, Seattle, Washington 98195
| | - Marianne Rohrbach
- Division of Metabolism, Connective Tissue Unit, University Children's Hospital Zurich, Children's Research Center, 8032 Zurich, Switzerland
| | - Cecilia Giunta
- Division of Metabolism, Connective Tissue Unit, University Children's Hospital Zurich, Children's Research Center, 8032 Zurich, Switzerland.
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Van Damme T, Syx D, Coucke P, Symoens S, De Paepe A, Malfait F. Genetics of the Ehlers–Danlos syndrome: more than collagen disorders. Expert Opin Orphan Drugs 2015. [DOI: 10.1517/21678707.2015.1022528] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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Ishikawa Y, Boudko S, Bächinger HP. Ziploc-ing the structure: Triple helix formation is coordinated by rough endoplasmic reticulum resident PPIases. Biochim Biophys Acta Gen Subj 2015; 1850:1983-93. [PMID: 25583561 DOI: 10.1016/j.bbagen.2014.12.024] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 12/26/2014] [Accepted: 12/29/2014] [Indexed: 11/18/2022]
Abstract
BACKGROUND Protein folding is crucial for proteins' specific functions and is facilitated by various types of enzymes and molecular chaperones. The peptidyl prolyl cis/trans isomerases (PPIase) are one of these families of enzymes. They ubiquitously exist inside the cell and there are eight PPIases in the rough endoplasmic reticulum (rER), a compartment where the folding of most secreted proteins occurs. SCOPE OF REVIEW We review the functional and structural aspects of individual rER resident PPIases. Furthermore, we specifically discuss the role of these PPIases during collagen biosynthesis, since collagen is the most abundant protein in humans, is synthesized in the rER, and contains a proportionally high number of proline residues. MAJOR CONCLUSIONS The rER resident PPIases recognize different sets of substrates and facilitate their folding. Although they are clearly catalysts for protein folding, they also have more broad and multifaceted functions. We propose that PPIases coordinate collagen biosynthesis in the rER. GENERAL SIGNIFICANCE This review expands our understanding of collagen biosynthesis by explaining the influence of novel indirect mechanisms of regulating folding and this is also explored for PPIases. We also suggest future directions of research to obtain a better understanding of collagen biosynthesis and functions of PPIases in the rER. This article is part of a Special Issue entitled Proline-directed Foldases: Cell Signaling Catalysts and Drug Targets.
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Affiliation(s)
- Yoshihiro Ishikawa
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, OR 97239, USA; Shriners Hospital for Children, Research Department, Portland, OR 97239, USA
| | - Sergei Boudko
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, OR 97239, USA; Shriners Hospital for Children, Research Department, Portland, OR 97239, USA
| | - Hans Peter Bächinger
- Department of Biochemistry and Molecular Biology, Oregon Health & Science University, Portland, OR 97239, USA; Shriners Hospital for Children, Research Department, Portland, OR 97239, USA.
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Bertin A, Hanna P, Otarola G, Fritz A, Henriquez JP, Marcellini S. Cellular and molecular characterization of a novel primary osteoblast culture from the vertebrate model organism Xenopus tropicalis. Histochem Cell Biol 2014; 143:431-42. [DOI: 10.1007/s00418-014-1289-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/15/2014] [Indexed: 01/30/2023]
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Abstract
Disruptions in procollagen synthesis, trafficking and secretion by cells occur in multiple connective tissue diseases. Traditionally, these disruptions are studied by pulse-chase labeling with radioisotopes. However, significant DNA damage, excessive accumulation of reactive oxygen species and formation of other free radicals have been well documented in the literature at typical radioisotope concentrations used for pulse-chase experiments. Therefore, it is important to keep in mind that the resulting cell stress response might affect interpretation of the data, particularly with respect to abnormal function of procollagen-producing cells. In this study, we describe an alternative method of pulse-chase procollagen labeling with azidohomoalanine, a noncanonical amino acid that replaces methionine in newly synthesized protein chains and can be detected via highly selective click chemistry reactions. At least in fibroblast culture, this approach is more efficient than traditional radioisotopes and has fewer, if any, unintended effects on cell function. To illustrate its applications, we demonstrate delayed procollagen folding and secretion by cells from an osteogenesis imperfecta patient with a Cys substitution for Gly766 in the triple helical region of the α1(I) chain of type I procollagen.
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Affiliation(s)
- Lynn S. Mirigian
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
- Department of Cell Biology, University of Texas Medical Branch, Galveston, TX, USA
| | - Elena Makareeva
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Sergey Leikin
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
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Ishikawa Y, Bächinger HP. A substrate preference for the rough endoplasmic reticulum resident protein FKBP22 during collagen biosynthesis. J Biol Chem 2014; 289:18189-201. [PMID: 24821723 DOI: 10.1074/jbc.m114.561944] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The biosynthesis of collagens occurs in the rough endoplasmic reticulum and requires a large numbers of molecular chaperones, foldases, and post-translational modification enzymes. Collagens contain a large number of proline residues that are post-translationally modified to 3-hydroxyproline or 4-hydroxyproline, and the rate-limiting step in formation of the triple helix is the cis-trans isomerization of peptidyl-proline bonds. This step is catalyzed by peptidyl-prolyl cis-trans isomerases. There are seven peptidyl-prolyl cis-trans isomerases in the rER, and so far, two of these enzymes, cyclophilin B and FKBP65, have been shown to be involved in collagen biosynthesis. The absence of either cyclophilin B or FKBP65 leads to a recessive form of osteogenesis imperfecta. The absence of FKBP22 leads to a kyphoscoliotic type of Ehlers-Danlos syndrome (EDS), and this type of EDS is classified as EDS type VI, which can also be caused by a deficiency in lysyl-hydroxylase 1. However, the lack of FKBP22 shows a wider spectrum of clinical phenotypes than the absence of lysyl-hydroxylase 1 and additionally includes myopathy, hearing loss, and aortic rupture. Here we show that FKBP22 catalyzes the folding of type III collagen and interacts with type III collagen, type VI collagen, and type X collagen, but not with type I collagen, type II collagen, or type V collagen. These restrictive interactions might help explain the broader phenotype observed in patients that lack FKBP22.
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Affiliation(s)
- Yoshihiro Ishikawa
- From the Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon 97239 and the Research Department, Shriners Hospital for Children, Portland, Oregon 97239
| | - Hans Peter Bächinger
- From the Department of Biochemistry and Molecular Biology, Oregon Health and Science University, Portland, Oregon 97239 and the Research Department, Shriners Hospital for Children, Portland, Oregon 97239
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42
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Raychaudhuri S, Loew C, Körner R, Pinkert S, Theis M, Hayer-Hartl M, Buchholz F, Hartl F. Interplay of Acetyltransferase EP300 and the Proteasome System in Regulating Heat Shock Transcription Factor 1. Cell 2014; 156:975-85. [DOI: 10.1016/j.cell.2014.01.055] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 10/20/2013] [Accepted: 01/23/2014] [Indexed: 12/22/2022]
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43
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A molecular ensemble in the rER for procollagen maturation. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2013; 1833:2479-91. [DOI: 10.1016/j.bbamcr.2013.04.008] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Revised: 04/06/2013] [Accepted: 04/08/2013] [Indexed: 01/18/2023]
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44
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Gualeni B, Rajpar MH, Kellogg A, Bell PA, Arvan P, Boot-Handford RP, Briggs MD. A novel transgenic mouse model of growth plate dysplasia reveals that decreased chondrocyte proliferation due to chronic ER stress is a key factor in reduced bone growth. Dis Model Mech 2013; 6:1414-25. [PMID: 24046357 PMCID: PMC3820264 DOI: 10.1242/dmm.013342] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 09/05/2013] [Indexed: 01/09/2023] Open
Abstract
Disease mechanisms leading to different forms of chondrodysplasia include extracellular matrix (ECM) alterations and intracellular stress resulting in abnormal changes to chondrocyte proliferation and survival. Delineating the relative contribution of these two disease mechanisms is a major challenge in understanding disease pathophysiology in genetic skeletal diseases and a prerequisite for developing effective therapies. To determine the influence of intracellular stress and changes in chondrocyte phenotype to the development of chondrodysplasia, we targeted the expression of the G2320R mutant form of thyroglobulin to the endoplasmic reticulum (ER) of resting and proliferating chondrocytes. Previous studies on this mutant protein have shown that it induces intracellular aggregates and causes cell stress and death in the thyroid gland. The expression and retention of this exogenous mutant protein in resting and proliferating chondrocytes resulted in a chronic cell stress response, growth plate dysplasia and reduced bone growth, without inducing any alterations to the architecture and organization of the cartilage ECM. More significantly, the decreased bone growth seemed to be the direct result of reduced chondrocyte proliferation in the proliferative zone of growth plates in transgenic mice, without transcriptional activation of a classical unfolded protein response (UPR) or apoptosis. Overall, these data show that mutant protein retention in the ER of resting and proliferative zone chondrocytes is sufficient to cause disrupted bone growth. The specific disease pathways triggered by mutant protein retention do not necessarily involve a prototypic UPR, but all pathways impact upon chondrocyte proliferation in the cartilage growth plate.
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Affiliation(s)
- Benedetta Gualeni
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, University of Manchester, Manchester, M13 9PT, UK
| | - M. Helen Rajpar
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, University of Manchester, Manchester, M13 9PT, UK
| | - Aaron Kellogg
- University of Michigan Health System, Ann Arbor, MI 48109, USA
| | - Peter A. Bell
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, University of Manchester, Manchester, M13 9PT, UK
| | - Peter Arvan
- University of Michigan Health System, Ann Arbor, MI 48109, USA
| | - Raymond P. Boot-Handford
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, University of Manchester, Manchester, M13 9PT, UK
| | - Michael D. Briggs
- Wellcome Trust Centre for Cell-Matrix Research, Faculty of Life Sciences, University of Manchester, Manchester, M13 9PT, UK
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Iwamoto S, Isoyama M, Hirano M, Yamaya K, Ito Y, Matsuo I, Totani K. Reconstructed glycan profile for evaluation of operating status of the endoplasmic reticulum glycoprotein quality control. Glycobiology 2012; 23:121-31. [DOI: 10.1093/glycob/cws130] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
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46
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Rohrbach M, Giunta C. Recessive osteogenesis imperfecta: clinical, radiological, and molecular findings. AMERICAN JOURNAL OF MEDICAL GENETICS PART C-SEMINARS IN MEDICAL GENETICS 2012; 160C:175-89. [PMID: 22791419 DOI: 10.1002/ajmg.c.31334] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Osteogenesis imperfecta (OI) or "brittle bone disease" is currently best described as a group of hereditary connective tissue disorders related to primary defects in type I procollagen, and to alterations in type I procollagen biosynthesis, both associated with osteoporosis and increased susceptibility to bone fractures. Initially, the autosomal dominant forms of OI, caused by mutations in either COL1A1 or COL1A2, were described. However, for decades, the molecular defect of a small percentage of patients clinically diagnosed with OI has remained elusive. It has been in the last 6 years that the genetic causes of several forms of OI with autosomal recessive inheritance have been characterized. These comprise defects of collagen chaperones, and proteins involved in type I procollagen assembly, processing and maturation, as well as proteins involved in the formation and homeostasis of bone tissue. This article reviews the recently characterized forms of recessive OI, focusing in particular on their clinical and molecular findings, and on their radiological characterisation. Clinical management and treatment of OI in general will be discussed, too.
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Affiliation(s)
- Marianne Rohrbach
- Connective Tissue Unit, Division of Metabolism, University Children's Hospital and Children's Research Center, Zurich, Switzerland
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47
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Bianchi L, Gagliardi A, Gioia R, Besio R, Tani C, Landi C, Cipriano M, Gimigliano A, Rossi A, Marini JC, Forlino A, Bini L. Differential response to intracellular stress in the skin from osteogenesis imperfecta Brtl mice with lethal and non lethal phenotype: a proteomic approach. J Proteomics 2012; 75:4717-33. [PMID: 22846432 DOI: 10.1016/j.jprot.2012.01.038] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2011] [Revised: 01/25/2012] [Accepted: 01/30/2012] [Indexed: 01/07/2023]
Abstract
Phenotypic variability in the presence of an identical molecular defect is a recurrent feature in heritable disorders and it was also reported in osteogenesis imperfecta (OI). OI is a prototype for skeletal dysplasias mainly caused by mutations in the two genes coding for type I collagen. No definitive cure is available for this disorder, but the understanding of molecular basis in OI phenotypic modulation will have a pivotal role in identifying possible targets to develop novel drug therapy. We used a functional proteomic approach to address the study of phenotypic variability using the skin of the OI murine model Brtl. Brtl mice reproduce the molecular defect, dominant transmission and phenotypic variability of human OI patients. In the presence of a Gly349Cys substitution in α1(I)-collagen Brtl mice can have a lethal or a moderately severe outcome. Differential expression of chaperones, proteasomal subunits, metabolic enzymes, and proteins related to cellular fate demonstrated that a different ability to adapt to cellular stress distinguished mutant from wild-type mice and mutant lethal from surviving mutant animals. Interestingly, class discovery analysis identified clusters of differentially expressed proteins associated with a specific outcome, and functional analysis contributed to a deeper investigation into biochemical and cellular pathways affected by the disease. This article is part of a Special Issue entitled: Translational Proteomics.
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Affiliation(s)
- Laura Bianchi
- Functional Proteomics Lab., Department of Biotechnology, Section of Biochemistry and Molecular Biology, University of Siena, Siena, Italy
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Martínez-Glez V, Valencia M, Caparrós-Martín JA, Aglan M, Temtamy S, Tenorio J, Pulido V, Lindert U, Rohrbach M, Eyre D, Giunta C, Lapunzina P, Ruiz-Perez VL. Identification of a mutation causing deficient BMP1/mTLD proteolytic activity in autosomal recessive osteogenesis imperfecta. Hum Mutat 2011; 33:343-50. [PMID: 22052668 DOI: 10.1002/humu.21647] [Citation(s) in RCA: 140] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Accepted: 10/27/2011] [Indexed: 11/11/2022]
Abstract
Herein, we have studied a consanguineous Egyptian family with two children diagnosed with severe autosomal recessive osteogenesis imperfecta (AR-OI) and a large umbilical hernia. Homozygosity mapping in this family showed lack of linkage to any of the previously known AR-OI genes, but revealed a 10.27 MB homozygous region on chromosome 8p in the two affected sibs, which comprised the procollagen I C-terminal propeptide (PICP) endopeptidase gene BMP1. Mutation analysis identified both patients with a Phe249Leu homozygous missense change within the BMP1 protease domain involving a residue, which is conserved in all members of the astacin group of metalloproteases. Type I procollagen analysis in supernatants from cultured fibroblasts demonstrated abnormal PICP processing in patient-derived cells consistent with the mutation causing decreased BMP1 function. This was further confirmed by overexpressing wild type and mutant BMP1 longer isoform (mammalian Tolloid protein [mTLD]) in NIH3T3 fibroblasts and human primary fibroblasts. While overproduction of normal mTLD resulted in a large proportion of proα1(I) in the culture media being C-terminally processed, proα1(I) cleavage was not enhanced by an excess of the mutant protein, proving that the Phe249Leu mutation leads to a BMP1/mTLD protein with deficient PICP proteolytic activity. We conclude that BMP1 is an additional gene mutated in AR-OI.
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Affiliation(s)
- Víctor Martínez-Glez
- Centro de Investigación Biomédica en Red de Enfermedades Raras, Instituto de Salud Carlos III, Madrid, Spain
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49
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Xiao J, Madhan B, Li Y, Brodsky B, Baum J. Osteogenesis imperfecta model peptides: incorporation of residues replacing Gly within a triple helix achieved by renucleation and local flexibility. Biophys J 2011; 101:449-58. [PMID: 21767498 DOI: 10.1016/j.bpj.2011.06.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2010] [Revised: 06/01/2011] [Accepted: 06/06/2011] [Indexed: 10/18/2022] Open
Abstract
Missense mutations, which replace one Gly with a larger residue in the repeating sequence of the type I collagen triple helix, lead to the hereditary bone disorder osteogenesis imperfecta (OI). Previous studies suggest that these mutations may interfere with triple-helix folding. NMR was used to investigate triple-helix formation in a series of model peptides where the residue replacing Gly, as well as the local sequence environment, was varied. NMR measurement of translational diffusion coefficients allowed the identification of partially folded species. When Gly was replaced by Ala, the Ala residue was incorporated into a fully folded triple helix, whereas replacement of Gly by Ser or Arg resulted in the presence of some partially folded species, suggesting a folding barrier. Increasing the triple-helix stability of the sequence N-terminal to a Gly-to-Ser replacement allowed complete triple-helix folding, whereas with the substitution of Arg, with its large side chain, the peptide achieved full folding only after flexible residues were introduced N-terminal to the mutation site. These studies shed light on the factors important for accommodation of Gly mutations within the triple helix and may relate to the varying severity of OI.
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Affiliation(s)
- Jianxi Xiao
- Department of Chemistry and Chemical Biology, BIOMAPS Institute, Rutgers University, Piscataway, New Jersey, USA
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