1
|
Qasim H, Khan H, Zeb H, Ahmad A, Ilyas M, Zahoor M, Umar MN, Ullah R, Ali EA. A novel variant in the FLNB gene associated with spondylocarpotarsal synostosis syndrome. J Basic Clin Physiol Pharmacol 2024; 0:jbcpp-2024-0031. [PMID: 38743867 DOI: 10.1515/jbcpp-2024-0031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2024] [Accepted: 04/30/2024] [Indexed: 05/16/2024]
Abstract
OBJECTIVES Genetic disorders involved in skeleton system arise due to the disturbance in skeletal development, growth and homeostasis. Filamin B is an actin binding protein which is large dimeric protein which cross link actin cytoskeleton filaments into dynamic structure. A single nucleotide changes in the FLNB gene causes spondylocarpotarsal synostosis syndrome, a rare bone disorder due to which the fusion of carpels and tarsals synostosis occurred along with fused vertebrae. In the current study we investigated a family residing in north-western areas of Pakistan. METHODS The whole exome sequencing of proband was performed followed by Sanger sequencing of all family members of the subject to validate the variant segregation within the family. Bioinformatics tools were utilized to assess the pathogenicity of the variant. RESULTS Whole Exome Sequencing revealed a novel variant (NM_001457: c.209C>T and p.Pro70Leu) in the FLNB gene which was homozygous missense mutation in the FLNB gene. The variant was further validated and visualized by Sanger sequencing and protein structure studies respectively as mentioned before. CONCLUSIONS The findings have highlighted the importance of the molecular diagnosis in SCT (spondylocarpotarsal synostosis syndrome) for genetic risk counselling in consanguineous families.
Collapse
Affiliation(s)
- Hina Qasim
- Centre for Omic Sciences, Islamia College University Peshawar, Peshawar, Pakistan
| | - Hayat Khan
- Centre for Omic Sciences, Islamia College University Peshawar, Peshawar, Pakistan
| | - Humaira Zeb
- Centre for Omic Sciences, Islamia College University Peshawar, Peshawar, Pakistan
| | - Akmal Ahmad
- Centre for Human Genetics, 66934 Hazara University Mansehra , Mansehra, Pakistan
| | - Muhammad Ilyas
- Centre for Omic Sciences, Islamia College University Peshawar, Peshawar, Pakistan
| | - Muhammad Zahoor
- Department of Biochemistry, 66714 University of Malakand , Chakdara, Dir Lower, KPK, Pakistan
| | | | - Riaz Ullah
- Department of Pharmacognosy, College of Pharmacy, 37850 King Saud University , Riyadh, Saudi Arabia
| | - Essam A Ali
- Department of Pharmaceutical Chemistry, 37850 College of Pharmacy King Saud University , Riyadh, Saudi Arabia
| |
Collapse
|
2
|
Syx D, Delbaere S, Bui C, De Clercq A, Larson G, Mizumoto S, Kosho T, Fournel-Gigleux S, Malfait F. Alterations in glycosaminoglycan biosynthesis associated with the Ehlers-Danlos syndromes. Am J Physiol Cell Physiol 2022; 323:C1843-C1859. [PMID: 35993517 DOI: 10.1152/ajpcell.00127.2022] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Proteoglycans consist of a core protein substituted with one or more glycosaminoglycan (GAG) chains and execute versatile functions during many physiological and pathological processes. The biosynthesis of GAG chains is a complex process that depends on the concerted action of a variety of enzymes. Central to the biosynthesis of heparan sulfate (HS) and chondroitin sulfate/dermatan sulfate (CS/DS) GAG chains is the formation of a tetrasaccharide linker region followed by biosynthesis of HS or CS/DS-specific repeating disaccharide units, which then undergo modifications and epimerization. The importance of these biosynthetic enzymes is illustrated by several severe pleiotropic disorders that arise upon their deficiency. The Ehlers-Danlos syndromes (EDS) constitute a special group among these disorders. Although most EDS types are caused by defects in fibrillar types I, III, or V collagen, or their modifying enzymes, a few rare EDS types have recently been linked to defects in GAG biosynthesis. Spondylodysplastic EDS (spEDS) is caused by defective formation of the tetrasaccharide linker region, either due to β4GalT7 or β3GalT6 deficiency, whereas musculocontractural EDS (mcEDS) results from deficiency of D4ST1 or DS-epi1, impairing DS formation. This narrative review highlights the consequences of GAG deficiency in these specific EDS types, summarizes the associated phenotypic features and the molecular spectrum of reported pathogenic variants, and defines the current knowledge on the underlying pathophysiological mechanisms based on studies in patient-derived material, in vitro analyses, and animal models.
Collapse
Affiliation(s)
- Delfien Syx
- Department of Biomolecular Medicine, Center for Medical Genetics, Ghent University, Ghent, Belgium
| | - Sarah Delbaere
- Department of Biomolecular Medicine, Center for Medical Genetics, Ghent University, Ghent, Belgium
| | | | - Adelbert De Clercq
- Department of Biomolecular Medicine, Center for Medical Genetics, Ghent University, Ghent, Belgium.,Flanders Research Institute for Agriculture, Fisheries and Food (ILVO), Ostend, Belgium
| | - Göran Larson
- Department of Laboratory Medicine, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.,Laboratory of Clinical Chemistry, Sahlgrenska University Hospital, Gothenburg, Sweden
| | - Shuji Mizumoto
- Department of Pathobiochemistry, Faculty of Pharmacy, Meijo University, Nagoya, Japan
| | - Tomoki Kosho
- Center for Medical Genetics, Shinshu University Hospital, Matsumoto, Japan.,Department of Medical Genetics, Shinshu University School of Medicine, Matsumoto, Japan
| | | | - Fransiska Malfait
- Department of Biomolecular Medicine, Center for Medical Genetics, Ghent University, Ghent, Belgium
| |
Collapse
|
3
|
Minatogawa M, Hirose T, Mizumoto S, Yamaguchi T, Nagae C, Taki M, Yamada S, Watanabe T, Kosho T. Clinical and pathophysiological delineation of musculocontractural Ehlers-Danlos syndrome caused by dermatan sulfate epimerase deficiency (mcEDS-DSE): A detailed and comprehensive glycobiological and pathological investigation in a novel patient. Hum Mutat 2022; 43:1829-1836. [PMID: 35842784 DOI: 10.1002/humu.24437] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Revised: 06/26/2022] [Accepted: 07/07/2022] [Indexed: 01/24/2023]
Abstract
Musculocontractural Ehlers-Danlos syndrome caused by dermatan sulfate epimerase deficiency (mcEDS-DSE) is a rare connective tissue disorder. This is the first report describing the detailed and comprehensive clinical and pathophysiological features of mcEDS-DSE. The patient, with a novel homozygous nonsense variant (NM_013352.4:c.2601C>A:p.(Tyr867*)), exhibited mild skin hyperextensibility without fragility and small joint hypermobility, but developed recurrent large subcutaneous hematomas. Dermatan sulfate (DS) moieties on chondroitin sulfate/DS proteoglycans were significantly decreased, but remained present, in skin fibroblasts. Electron microscopy examination of skin specimens, including cupromeronic blue-staining to visualize glycosaminoglycan (GAG) chains, revealed coexistence of normally assembled collagen fibrils with attached curved GAG chains and dispersed collagen fibrils with linear GAG chains from attached collagen fibrils across interfibrillar spaces to adjacent fibrils. Residual activity of DS-epi1, encoded by DSE, and/or compensation by DS-epi2, a minor homolog of DS-epi1, may contribute to the mild skin involvement through this "mosaic" pattern of collagen fibril assembly.
Collapse
Affiliation(s)
- Mari Minatogawa
- Department of Medical Genetics, Shinshu University School of Medicine, Matsumoto, Japan.,Center for Medical Genetics, Shinshu University Hospital, Matsumoto, Japan
| | - Takuya Hirose
- Laboratory of Veterinary Anatomy, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Japan
| | - Shuji Mizumoto
- Department of Pathobiochemistry, Faculty of Pharmacy, Meijo University, Nagoya, Japan
| | - Tomomi Yamaguchi
- Department of Medical Genetics, Shinshu University School of Medicine, Matsumoto, Japan.,Center for Medical Genetics, Shinshu University Hospital, Matsumoto, Japan.,Division of Clinical Sequencing, Shinshu University School of Medicine, Matsumoto, Japan
| | - Chiai Nagae
- Department of Pediatrics, St. Marianna University School of Medicine, Kawasaki, Japan
| | - Masashi Taki
- Department of Pediatrics, St. Marianna University School of Medicine, Yokohama City Seibu Hospital, Yokohama, Japan
| | - Shuhei Yamada
- Department of Pathobiochemistry, Faculty of Pharmacy, Meijo University, Nagoya, Japan
| | - Takafumi Watanabe
- Laboratory of Veterinary Anatomy, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Japan
| | - Tomoki Kosho
- Department of Medical Genetics, Shinshu University School of Medicine, Matsumoto, Japan.,Center for Medical Genetics, Shinshu University Hospital, Matsumoto, Japan.,Division of Clinical Sequencing, Shinshu University School of Medicine, Matsumoto, Japan.,Research Center for Supports to Advanced Science, Shinshu University, Matsumoto, Japan
| |
Collapse
|
4
|
The Specific Role of Dermatan Sulfate as an Instructive Glycosaminoglycan in Tissue Development. Int J Mol Sci 2022; 23:ijms23137485. [PMID: 35806490 PMCID: PMC9267682 DOI: 10.3390/ijms23137485] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 07/02/2022] [Accepted: 07/03/2022] [Indexed: 11/16/2022] Open
Abstract
The crucial roles of dermatan sulfate (DS) have been demonstrated in tissue development of the cutis, blood vessels, and bone through construction of the extracellular matrix and cell signaling. Although DS classically exerts physiological functions via interaction with collagens, growth factors, and heparin cofactor-II, new functions have been revealed through analyses of human genetic disorders as well as of knockout mice with loss of DS-synthesizing enzymes. Mutations in human genes encoding the epimerase and sulfotransferase responsible for the biosynthesis of DS chains cause connective tissue disorders including spondylodysplastic type Ehlers–Danlos syndrome, characterized by skin hyperextensibility, joint hypermobility, and tissue fragility. DS-deficient mice show perinatal lethality, skin fragility, vascular abnormalities, thoracic kyphosis, myopathy-related phenotypes, acceleration of nerve regeneration, and impairments in self-renewal and proliferation of neural stem cells. These findings suggest that DS is essential for tissue development in addition to the assembly of collagen fibrils in the skin, and that DS-deficient knockout mice can be utilized as models of human genetic disorders that involve impairment of DS biosynthesis. This review highlights a novel role of DS in tissue development studies from the past decade.
Collapse
|