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Liang Q, Zhang Z, Ding B, Shao Y, Ding Q, Dai J, Hu X, Wu W, Wang X. A noncanonical splicing variant c.875-5 T > G in von Willebrand factor causes in-frame exon skipping and type 2A von Willebrand disease. Thromb Res 2024; 236:51-60. [PMID: 38387303 DOI: 10.1016/j.thromres.2024.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 01/16/2024] [Accepted: 02/01/2024] [Indexed: 02/24/2024]
Abstract
INTRODUCTION A novel variant involving noncanonical splicing acceptor site (c.875-5 T > G) in propeptide coding region of von Willebrand factor (VWF) was identified in a patient with type 2A von Willebrand disease (VWD), who co-inherited with a null variant (p.Tyr271*) and presented characteristic discrepancy of plasma level of VWF antigen and activity, and a selective reduction of both intermediate-molecular-weight (IMWMs) and high-molecular-weight VWF multimers (HMWMs). MATERIALS AND METHODS VWF mRNA transcripts obtained from peripheral leukocytes and platelets of the patients were investigated to analyze the consequence of c.875-5 T > G on splicing. The impact of the variant on expression and multimer assembly was further analyzed by in vitro expression studies in AtT-20 cells. The intracellular processing of VWF mutant and the Weibel-Palade bodies (WPBs) formation was evaluated by immunofluorescence staining and electron microscopy. RESULTS The mRNA transcript analysis revealed that c.875-5 T > G variant led to exon 8 skipping and an in-frame deletion of 41 amino acids in the D1 domain of VWF (p.Ser292_Glu333delinsLys), yielding a truncated propeptide. Consistent with the patient's laboratory manifestations, the AtT-20 cells transfected with mutant secreted less VWF, with the VWF antigen level in conditioned medium 47 % of wild-type. A slight retention in the endoplasmic reticulum was observed for the mutant. Almost complete loss of IMWMs and HMWMs in the medium and impaired WPBs formation in the cell, indicating truncated VWF propeptide lost its chaperon-like function for VWF multimerization and tubular storage. CONCLUSIONS The VWF splicing site variant (c.875-5 T > G) causes propeptide truncation, severely compromising VWF multimer assembly and tubular storage.
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Affiliation(s)
- Qian Liang
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Ziqi Zhang
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Department of Molecular Biology, Shanghai Center for Clinical Laboratory, Shanghai, China
| | - Biying Ding
- State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Yanyan Shao
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Qiulan Ding
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Collaborative Innovation Center of Hematology, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Jing Dai
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China
| | - Xiaobo Hu
- Department of Molecular Biology, Shanghai Center for Clinical Laboratory, Shanghai, China.
| | - Wenman Wu
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Collaborative Innovation Center of Hematology, Shanghai Jiaotong University School of Medicine, Shanghai, China.
| | - Xuefeng Wang
- Department of Laboratory Medicine, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai, China; Collaborative Innovation Center of Hematology, Shanghai Jiaotong University School of Medicine, Shanghai, China.
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Sadler B, Christopherson PA, Perry CL, Bellissimo DB, Haberichter SL, Haller G, Antunes L, Flood VH, Di Paola J, Montgomery RR. Characterization of copy-number variants in a large cohort of patients with von Willebrand disease reveals a relationship between disrupted regions and disease type. Res Pract Thromb Haemost 2023; 7:102232. [PMID: 38077814 PMCID: PMC10704516 DOI: 10.1016/j.rpth.2023.102232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 09/13/2023] [Accepted: 10/01/2023] [Indexed: 02/12/2024] Open
Abstract
Background Genetic analysis for von Willebrand disease (VWD) commonly utilizes DNA sequencing to identify variants in the von Willebrand factor (VWF) gene; however, this technique cannot always detect copy-number variants (CNVs). Additional mapping of CNVs in patients with VWD is needed. Objectives This study aimed to characterize CNVs in a large sample of VWF mutation-negative VWD patients. Methods To determine the role of CNVs in VWD, a VWF high-resolution comparative genomic hybridization array was custom-designed to avoid multiple sequence variations, repeated sequences, and the VWF pseudogene. This was performed on 204 mutation-negative subjects for whom clinical variables were also available. Results Among the 204 patients, 7 unique CNVs were found, with a total of 24 CNVs (12%). Of the 7 unique CNVs, 1 was novel, 1 was found in a VWF database, and 5 were previously reported. All patients with type 1C VWD and a CNV had the same exon 33 and 34 in-frame deletion. Certain clinical variables were also significantly different between those with and without CNVs. Conclusion The in-frame deletion in patients with type 1C VWD exactly matches the D4N module of the D4 domain, a region where mutations and deletions are known to affect clearance. We observed significantly higher VWF-to-ristocetin cofactor levels in patients with type 1C VWD and a CNV than in patients without a CNV, suggesting a relationship between CNVs and the increased clearance observed in patients with type 1C VWD. Glycoprotein IbM activity was significantly lower in patients with type 1 VWD and a CNV than in patients without a CNV, suggesting that platelet binding is more affected by CNVs than single base pair mutations. This work elucidates some of the underlying genetic mechanisms of CNVs in these patients.
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Affiliation(s)
- Brooke Sadler
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA
| | | | | | - Daniel B. Bellissimo
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Sandra L. Haberichter
- Versiti Blood Research Institute, Milwaukee, Wisconsin, USA
- Division of Pediatric Hematology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Gabe Haller
- Department of Neurosurgery, Washington University, St. Louis, Missouri, USA
| | - Lilian Antunes
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Veronica H. Flood
- Versiti Blood Research Institute, Milwaukee, Wisconsin, USA
- Division of Pediatric Hematology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Jorge Di Paola
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Robert R. Montgomery
- Versiti Blood Research Institute, Milwaukee, Wisconsin, USA
- Division of Pediatric Hematology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Zimmerman Program Investigators
- Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri, USA
- Versiti Blood Research Institute, Milwaukee, Wisconsin, USA
- Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
- Division of Pediatric Hematology, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
- Department of Neurosurgery, Washington University, St. Louis, Missouri, USA
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Okamoto S, Tamura S, Sanda N, Odaira K, Hayakawa Y, Mukaide M, Suzuki A, Kanematsu T, Hayakawa F, Katsumi A, Kiyoi H, Kojima T, Matsushita T, Suzuki N. VWF-Gly2752Ser, a novel non-cysteine substitution variant in the CK domain, exhibits severe secretory impairment by hampering C-terminal dimer formation. J Thromb Haemost 2022; 20:1784-1796. [PMID: 35491445 DOI: 10.1111/jth.15746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2021] [Revised: 04/11/2022] [Accepted: 04/22/2022] [Indexed: 08/31/2023]
Abstract
BACKGROUND Von Willebrand factor (VWF) is a multimeric glycoprotein that plays important roles in hemostasis and thrombosis. C-terminal interchain-disulfide bonds in the cystine knot (CK) domain are essential for VWF dimerization. Previous studies have reported that missense variants of cysteine in the CK domain disrupt the intrachain-disulfide bond and cause type 3 von Willebrand disease (VWD). However, type 3 VWD-associated noncysteine substitution variants in the CK domain have not been reported. OBJECTIVE To investigate the molecular mechanism of a novel non-cysteine variant in the CK domain, VWF c.8254 G>A (p.Gly2752Ser), which was identified in a patient with type 3 VWD as homozygous. METHODS Genetic analysis was performed by whole exome sequencing and Sanger sequencing. VWF multimer analysis was performed using SDS-agarose electrophoresis. VWF production and subcellular localization were analyzed using ex vivo endothelial colony forming cells (ECFCs) and an in vitro recombinant VWF (rVWF) expression system. RESULTS The patient was homozygous for VWF-Gly2752Ser. Plasma VWF enzyme-linked immunosorbent assay showed that the VWF antigen level of the patient was 1.2% compared with healthy subjects. A tiny amount of VWF was identified in the patient's ECFC. Multimer analysis revealed that the circulating VWF-Gly2752Ser presented only low molecular weight multimers. Subcellular localization analysis of VWF-Gly2752Ser-transfected cell lines showed that rVWF-Gly2752Ser was severely impaired in its ER-to-Golgi trafficking. CONCLUSION VWF-Gly2752Ser causes severe secretory impairment because of its dimerization failure. This is the first report of a VWF variant with a noncysteine substitution in the CK domain that causes type 3 VWD.
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Affiliation(s)
- Shuichi Okamoto
- Department of Hematology and Oncology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Shogo Tamura
- Division of Cellular and Genetic Sciences, Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Naomi Sanda
- Department of Medical Technique, Nagoya University Hospital, Nagoya, Japan
| | - Koya Odaira
- Division of Cellular and Genetic Sciences, Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Yuri Hayakawa
- Division of Cellular and Genetic Sciences, Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Masato Mukaide
- Division of Cellular and Genetic Sciences, Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Atsuo Suzuki
- Department of Medical Technique, Nagoya University Hospital, Nagoya, Japan
| | - Takeshi Kanematsu
- Department of Laboratory Medicine, Nagoya University Hospital, Nagoya, Japan
| | - Fumihiko Hayakawa
- Division of Cellular and Genetic Sciences, Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Akira Katsumi
- Department of Hematology, National Center for Geriatrics and Gerontology, Obu City, Japan
| | - Hitoshi Kiyoi
- Department of Hematology and Oncology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Tetsuhito Kojima
- Division of Cellular and Genetic Sciences, Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Japan
- Aichi Health Promotion Foundation, Nagoya, Japan
| | - Tadashi Matsushita
- Department of Laboratory Medicine, Nagoya University Hospital, Nagoya, Japan
- Department of Transfusion Medicine, Nagoya University Hospital, Nagoya, Japan
| | - Nobuaki Suzuki
- Department of Transfusion Medicine, Nagoya University Hospital, Nagoya, Japan
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Pagliari MT, Baronciani L, Cordiglieri C, Colpani P, Cozzi G, Siboni SM, Peyvandi F. The dominant p.Thr274Pro mutation in the von Willebrand factor propeptide causes the von Willebrand disease type 1 phenotype in two unrelated patients. Haemophilia 2022; 28:292-300. [PMID: 35064738 PMCID: PMC9303708 DOI: 10.1111/hae.14494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2021] [Revised: 12/20/2021] [Accepted: 01/04/2022] [Indexed: 11/28/2022]
Abstract
Background von Willebrand factor propeptide (VWFpp) plays an important role in VWF multimerization and storage. VWFpp mutations have been previously associated with types 1, 3 and 2A/IIC von Willebrand disease (VWD). Aims To characterize the novel p.Thr274Pro variant identified in two unrelated type 1 VWD patients. Methods Phenotype tests were performed to evaluate patients’ plasma and platelets following the current ISTH‐SSC guidelines. Molecular analysis was performed using next‐generation sequencing. The pcDNA3.1‐VWF‐WT and mutant pcDNA3.1‐VWF‐Thr274Pro expression vectors were transiently transfected into HEK293 cells to evaluate recombinant (r)VWF constitutive and regulated secretion. For the latter, the transfected cells were stimulated with phorbol‐12‐myristate‐13‐acetate. Immunofluorescence staining was performed to assess the localization of WT‐rVWF and Thr274Pro‐rVWF in endoplasmic reticulum, lysosomes, cis‐/trans‐Golgi and pseudo‐Weibel Palade bodies. Results Biochemical characterization of patients’ plasma samples indicated a type 1 VWD diagnosis. Both patients were heterozygous for the p.Thr274Pro variant. Hybrid Thr274Pro/WT‐rVWF showed a secretion reduction of 36±4% according to patients’ plasma VWF:Ag levels, whereas Thr274Pro‐rVWF secretion was strongly impaired (21±2%). The amount of rVWF in cell lysates was nearly normal for both Thr274P (62±17%) and Thr274Pro/WT‐rVWF (72±23%). The regulated secretion was impaired for Thr274Pro/WT‐rVWF, whereas Thr274Pro‐rVWF was not released at all. Immunofluorescence staining revealed no particular differences between WT and Thr274Pro‐rVWF, although Thr274Pro‐rVWF showed less pseudo‐Weibel Palade bodies with a rounder shape than WT‐rVWF. Conclusions The novel p.Thr274Pro mutation has a dominant effect and it is responsible of patients’ type 1 VWD phenotype through a combined mechanism of reduced synthesis, impaired secretion and multimerization.
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Affiliation(s)
- Maria Teresa Pagliari
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Angelo Bianchi Bonomi Hemophilia and Thrombosis Center and Università degli Studi di Milano, Department of Pathophysiology and Transplantation Milan Italy
| | - Luciano Baronciani
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico Angelo Bianchi Bonomi Hemophilia and Thrombosis Center Milan Italy
| | - Chiara Cordiglieri
- National Institute of Molecular Genetics ‘Romeo e Enrica Invernizzi’ ‐ INGM Milan Italy
| | - Paola Colpani
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico Angelo Bianchi Bonomi Hemophilia and Thrombosis Center Milan Italy
| | - Giovanna Cozzi
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico Angelo Bianchi Bonomi Hemophilia and Thrombosis Center Milan Italy
| | - Simona M. Siboni
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico Angelo Bianchi Bonomi Hemophilia and Thrombosis Center Milan Italy
| | - Flora Peyvandi
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico Angelo Bianchi Bonomi Hemophilia and Thrombosis Center Milan Italy
- Università degli Studi di Milano Department of Pathophysiology and Transplantation Milan Italy
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Characterization of large in-frame von Willebrand factor deletions highlights differing pathogenic mechanisms. Blood Adv 2021; 4:2979-2990. [PMID: 32609846 DOI: 10.1182/bloodadvances.2018027813] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2018] [Accepted: 05/02/2020] [Indexed: 11/20/2022] Open
Abstract
Copy number variation (CNV) is known to cause all von Willebrand disease (VWD) types, although the associated pathogenic mechanisms involved have not been extensively studied. Notably, in-frame CNV provides a unique opportunity to investigate how specific von Willebrand factor (VWF) domains influence the processing and packaging of the protein. Using multiplex ligation-dependent probe amplification, this study determined the extent to which CNV contributed to VWD in the Molecular and Clinical Markers for the Diagnosis and Management of Type 1 von Willebrand Disease cohort, highlighting in-frame deletions of exons 3, 4-5, 32-34, and 33-34. Heterozygous in vitro recombinant VWF expression demonstrated that, although deletion of exons 3, 32-34, and 33-34 all resulted in significant reductions in total VWF (P < .0001, P < .001, and P < .01, respectively), only deletion of exons 3 and 32-34 had a significant impact on VWF secretion (P < .0001). High-resolution microscopy of heterozygous and homozygous deletions confirmed these observations, indicating that deletion of exons 3 and 32-34 severely impaired pseudo-Weibel-Palade body (WPB) formation, whereas deletion of exons 33-34 did not, with this variant still exhibiting pseudo-WPB formation similar to wild-type VWF. In-frame deletions in VWD, therefore, contribute to pathogenesis via moderate or severe defects in VWF biosynthesis and secretion.
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Shigekiyo T, Udaka K, Sekimoto E, Shibata H, Ozaki S, Higuchi Y, Matsumoto M. Identification of a homozygous missense mutation (p.Cys379Gly) in the D1 domain of von Willebrand factor propeptide in a family with type 2A (IIC) von Willebrand disease. Haemophilia 2018; 24:e422-e425. [PMID: 30175488 DOI: 10.1111/hae.13605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Revised: 07/26/2018] [Accepted: 07/30/2018] [Indexed: 06/08/2023]
Affiliation(s)
- Toshio Shigekiyo
- Department of Hematology, Tokushima Prefectural Central Hospital, Tokushima, Japan
| | - Kengo Udaka
- Department of Hematology, Tokushima Prefectural Central Hospital, Tokushima, Japan
| | - Etsuko Sekimoto
- Department of Hematology, Tokushima Prefectural Central Hospital, Tokushima, Japan
| | - Hironobu Shibata
- Department of Hematology, Tokushima Prefectural Central Hospital, Tokushima, Japan
| | - Shuji Ozaki
- Department of Hematology, Tokushima Prefectural Central Hospital, Tokushima, Japan
| | - Yukio Higuchi
- Department of Orthopedics, Tokushima Prefectural Central Hospital, Tokushima, Japan
| | - Masanori Matsumoto
- Department of Blood Transfusion Medicine, Nara Medical University, Nara, Japan
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de Jong A, Eikenboom J. Von Willebrand disease mutation spectrum and associated mutation mechanisms. Thromb Res 2017; 159:65-75. [PMID: 28987708 DOI: 10.1016/j.thromres.2017.09.025] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2017] [Revised: 09/13/2017] [Accepted: 09/22/2017] [Indexed: 01/24/2023]
Abstract
Von Willebrand disease (VWD) is a bleeding disorder that is mainly caused by mutations in the multimeric protein von Willebrand factor (VWF). These mutations may lead to deficiencies in plasma VWF or dysfunctional VWF. VWF is a heterogeneous protein and over the past three decades, hundreds of VWF mutations have been identified. In this review we have organized all reported mutations, spanning a timeline from the late eighties until early 2017. This resulted in an overview of 750 unique mutations that are divided over the VWD types 1, 2A, 2B, 2M, 2N and 3. For many of these mutations the disease-causing effects have been characterized in vitro through expression studies, ex vivo by analysis of patient-derived endothelial cells, as well as in animal or (bio)physical models. Here we describe the mechanisms associated with the VWF mutations per VWD type.
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Affiliation(s)
- Annika de Jong
- Department of Internal Medicine, Division of Thrombosis and Hemostasis, Einthoven Laboratory for Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, The Netherlands
| | - Jeroen Eikenboom
- Department of Internal Medicine, Division of Thrombosis and Hemostasis, Einthoven Laboratory for Vascular and Regenerative Medicine, Leiden University Medical Center, Leiden, The Netherlands.
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Brehm MA. Von Willebrand factor processing. Hamostaseologie 2016; 37:59-72. [PMID: 28139814 DOI: 10.5482/hamo-16-06-0018] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Accepted: 11/03/2016] [Indexed: 11/05/2022] Open
Abstract
Von Willebrand factor (VWF) is a multimeric glycoprotein essential for primary haemostasis that is produced only in endothelial cells and megakaryocytes. Key to VWF's function in recruitment of platelets to the site of vascular injury is its multimeric structure. The individual steps of VWF multimer biosynthesis rely on distinct posttranslational modifications at specific pH conditions, which are realized by spatial separation of the involved processes to different cell organelles. Production of multimers starts with translocation and modification of the VWF prepropolypeptide in the endoplasmic reticulum to produce dimers primed for glycosylation. In the Golgi apparatus they are further processed to multimers that carry more than 300 complex glycan structures functionalized by sialylation, sulfation and blood group determinants. Of special importance is the sequential formation of disulfide bonds with different functions in structural support of VWF multimers, which are packaged, stored and further processed after secretion. Here, all these processes are being reviewed in detail including background information on the occurring biochemical reactions.
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Affiliation(s)
- Maria A Brehm
- PD Dr. Maria A. Brehm, Department of Pediatric Hematology and Oncology, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 22399 Hamburg, Germany, Tel.: +49 40 7410 58523, Fax: +49 40 7410 54601, E-Mail:
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