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Abdel-Naim AB, Kumar P, Bazuhair MA, Rizg WY, Niyazi HA, Alkuwaity K, Niyazi HA, Alharthy SA, Harakeh S, Haque S, Prakash A, Kumar V. Computational insights into dynamics and conformational stability of N-acetylmannosamine kinase mutations. J Biomol Struct Dyn 2024:1-11. [PMID: 38502682 DOI: 10.1080/07391102.2024.2323702] [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: 05/02/2023] [Accepted: 02/21/2024] [Indexed: 03/21/2024]
Abstract
The activity of UDP-GlcNAc 2-epimerase/ManNAc kinase (GNE) is essential for the biosynthesis of sialic acid, which is involved in cellular processes in health and diseases. GNE contains an N-terminal epimerase domain and a C-terminal kinase domain (N-acetylmannosamine kinase, MNK). Mutations of the GNE protein led to hypoactivity of the enzyme and cause sialurea or autosomal recessive inclusion body myopathy/Nonaka myopathy. Here, we used all-atom molecular dynamics (MD) simulations to comprehend the folding, dynamics and conformational stability of MNK variants, including the wild type (WT) and three mutants (H677R, V696M and H677R/V696M). The deleterious and destabilizing nature of MNK mutants were predicted using different prediction tools. Results predicted that mutations modulate the stability, flexibility and function of MNK. The effect of mutations on the conformational stability and dynamics of MNK was next studied through the free-energy landscape (FEL), hydrogen-bonds and secondary structure changes. The FEL results show that the mutations interfere with various conformational transitions in both WT and mutants, exposing the structural underpinnings of protein destabilization and unfolding brought on by mutation. We discover that, when compared to the other two mutations, V696M and H677R/V696M, H677R has the most harmful effects. These findings have a strong correlation with published experimental studies that demonstrate how these mutations disrupt MNK activity. Hence, this computational study describes the structural details to unravel the mutant effects at the atomistic resolution and has implications for understanding the GNE's physiological and pathological role.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Ashraf B Abdel-Naim
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia
- Mohamed Saeed Tamer Chair for Pharmaceutical Industries, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia
- Center of Excellence for Drug Research and Pharmaceutical Industries, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Pawan Kumar
- School of Computational & Integrative Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Mohammed A Bazuhair
- Center of Excellence for Drug Research and Pharmaceutical Industries, King Abdulaziz University, Jeddah, Saudi Arabia
- Department of Clinical Pharmacology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Waleed Y Rizg
- Mohamed Saeed Tamer Chair for Pharmaceutical Industries, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia
- Center of Excellence for Drug Research and Pharmaceutical Industries, King Abdulaziz University, Jeddah, Saudi Arabia
- Department of Pharmaceutics, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Hatoon A Niyazi
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Khalil Alkuwaity
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia
- Vaccines and Immunotherapy Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Hanouf A Niyazi
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Saif A Alharthy
- Department of Medical Laboratory Sciences, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
- Toxicology and Forensic Sciences Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Steve Harakeh
- King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
- Yousef Abdul Latif Jameel Scientific Chair of Prophetic Medicine Application, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Shafiul Haque
- Research and Scientific Studies Unit, College of Nursing and Health Sciences, Jazan University, Jazan, Saudi Arabia
- Gilbert and Rose-Marie Chagoury School of Medicine, Lebanese American University, Beirut, Lebanon
- Centre of Medical and Bio-Allied Health Sciences Research, Ajman University, Ajman, United Arab Emirates
| | - Amresh Prakash
- Amity Institute of Integrative Sciences and Health, Amity University Haryana, Gurgaon, India
| | - Vijay Kumar
- Amity Institute of Neuropsychology & Neurosciences, Amity University, Noida, India
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Mueller F, Witteveldt J, Macias S. Antiviral Defence Mechanisms during Early Mammalian Development. Viruses 2024; 16:173. [PMID: 38399949 PMCID: PMC10891733 DOI: 10.3390/v16020173] [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: 12/14/2023] [Revised: 01/11/2024] [Accepted: 01/20/2024] [Indexed: 02/25/2024] Open
Abstract
The type-I interferon (IFN) response constitutes the major innate immune pathway against viruses in mammals. Despite its critical importance for antiviral defence, this pathway is inactive during early embryonic development. There seems to be an incompatibility between the IFN response and pluripotency, the ability of embryonic cells to develop into any cell type of an adult organism. Instead, pluripotent cells employ alternative ways to defend against viruses that are typically associated with safeguard mechanisms against transposable elements. The absence of an inducible IFN response in pluripotent cells and the constitutive activation of the alternative antiviral pathways have led to the hypothesis that embryonic cells are highly resistant to viruses. However, some findings challenge this interpretation. We have performed a meta-analysis that suggests that the susceptibility of pluripotent cells to viruses is directly correlated with the presence of receptors or co-receptors for viral adhesion and entry. These results challenge the current view of pluripotent cells as intrinsically resistant to infections and raise the fundamental question of why these cells have sacrificed the major antiviral defence pathway if this renders them susceptible to viruses.
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Affiliation(s)
- Felix Mueller
- Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, King’s Buildings, Charlotte Auerbach Road, Edinburgh EH9 3FL, UK; (F.M.); (J.W.)
- Centre for Virus Research, MRC-University of Glasgow, Garscube Campus, 464 Bearsden Road, Glasgow G61 1QH, UK
| | - Jeroen Witteveldt
- Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, King’s Buildings, Charlotte Auerbach Road, Edinburgh EH9 3FL, UK; (F.M.); (J.W.)
| | - Sara Macias
- Institute of Immunology and Infection Research, School of Biological Sciences, University of Edinburgh, King’s Buildings, Charlotte Auerbach Road, Edinburgh EH9 3FL, UK; (F.M.); (J.W.)
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The Synthesis of UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine Kinase (GNE), α-dystroglycan, and β-galactoside α-2,3-sialyltransferase 6 (ST3Gal6) By Skeletal Muscle Cell As a Response To Infection with Trichinella Spiralis. Helminthologia 2022; 59:217-225. [PMID: 36694833 PMCID: PMC9831521 DOI: 10.2478/helm-2022-0027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Accepted: 08/17/2022] [Indexed: 12/23/2022] Open
Abstract
The Nurse cell of the parasitic nematode Trichinella spiralis is a unique structure established after genetic, morphological and functional modification of a small portion of invaded skeletal muscle fiber. Even if the newly developed cytoplasm of the Nurse cell is no longer contractile, this structure remains well integrated within the surrounding healthy tissue. Our previous reports suggested that this process is accompanied by an increased local biosynthesis of sialylated glycoproteins. In this work we examined the expressions of three proteins, functionally associated with the process of sialylation. The enzyme UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE) is a key initiator of the sialic acid biosynthetic pathway. The α-dystroglycan was the only identified sialylated glycoprotein in skeletal muscles by now, bearing sialyl-α-2,3-Gal-β-1,4-Gl-cNAc-β-1,2-Man-α-1-O-Ser/Thr glycan. The third protein of interest for this study was the enzyme β-galactoside α-2,3-sialyltransferase 6 (ST3Gal6), which transfers sialic acid preferably onto Gal-β-1,4-GlcNAc as an acceptor, and thus it was considered as a suitable candidate for the sialylation of the α-dystroglycan. The expressions of the three proteins were analyzed by real time-PCR and immunohistochemistry on modified methacarn fixed paraffin tissue sections of mouse skeletal muscle samples collected at days 0, 14 and 35 post infection. According to our findings, the up-regulation of GNE was a characteristic of the early and the late stage of the Nurse cell development. Additional features of this process were the elevated expressions of α-dystroglycan and the enzyme ST3Gal6. We provided strong evidence that an increased local synthesis of sialic acids is a trait of the Nurse cell of T. spiralis, and at least in part due to an overexpression of α-dystroglycan. In addition, circumstantially we suggest that the enzyme ST3Gal6 is engaged in the process of sialylation of the major oligosaccharide component of α-dystroglycan.
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Safety and efficacy of N-acetylmannosamine (ManNAc) in patients with GNE myopathy: an open-label phase 2 study. Genet Med 2021; 23:2067-2075. [PMID: 34257421 PMCID: PMC8553608 DOI: 10.1038/s41436-021-01259-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 06/09/2021] [Accepted: 06/11/2021] [Indexed: 01/09/2023] Open
Abstract
Purpose To evaluate the safety and efficacy of N-acetylmannosamine (ManNAc) in GNE myopathy, a genetic muscle disease caused by deficiency of the rate-limiting enzyme in N-acetylneuraminic acid (Neu5Ac) biosynthesis. Methods We conducted an open-label, phase 2, single-center (NIH, USA) study to evaluate oral ManNAc in 12 patients with GNE myopathy (ClinicalTrials.gov NCT02346461). Primary endpoints were safety and biochemical efficacy as determined by change in plasma Neu5Ac and sarcolemmal sialylation. Clinical efficacy was evaluated using secondary outcome measures as part of study extensions, and a disease progression model (GNE-DPM) was tested as an efficacy analysis method. Results Most drug-related adverse events were gastrointestinal, and there were no serious adverse events. Increased plasma Neu5Ac (+2,159 nmol/L, p < 0.0001) and sarcolemmal sialylation (p = 0.0090) were observed at day 90 compared to baseline. A slower rate of decline was observed for upper extremity strength (p = 0.0139), lower extremity strength (p = 0.0006), and the Adult Myopathy Assessment Tool (p = 0.0453), compared to natural history. Decreased disease progression was estimated at 12 (γ = 0.61 [95% CI: 0.09, 1.27]) and 18 months (γ = 0.55 [95% CI: 0.12, 1.02]) using the GNE-DPM. Conclusion ManNAc showed long-term safety, biochemical efficacy consistent with the intended mechanism of action, and preliminary evidence clinical efficacy in patients with GNE myopathy.
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Hou R, Huo X, Zhang S, Xu C, Huang Y, Xu X. Elevated levels of lead exposure and impact on the anti-inflammatory ability of oral sialic acids among preschool children in e-waste areas. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 699:134380. [PMID: 31678878 DOI: 10.1016/j.scitotenv.2019.134380] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Revised: 07/24/2019] [Accepted: 09/08/2019] [Indexed: 02/05/2023]
Abstract
The oral health of preschool children in an electronic waste (e-waste) area is susceptible to lead (Pb) exposure increasing the risk of dental caries and causing periodontitis and other oral diseases. The aim of the present study is to investigate the relationship between chronic exposure to Pb and oral anti-inflammatory potential of preschool children. For this analysis, 574 preschool children from 2.5 to 6 years of age were recruited between November and December 2017, in which 357 preschool children were from Guiyu (n = 357), an e-waste-contaminated town, and 217 from Haojiang Shantou. We measured the levels of child blood Pb, salivary sialic acid, serum interleukin-6 (IL-6) and serum tumor necrosis factor-α (TNF-α), and investigated the prevalence of dental caries in deciduous teeth. The medians of blood Pb levels, serum IL-6 and TNF-α were significantly higher in the Guiyu children than in Haojiang children. Concomitantly, salivary sialic acids were lower in the Guiyu children [9.58 (3.97, 18.42) mg/dL] than in Haojiang [17.57 (5.95, 24.23) mg/dL]. Additionally, the prevalence of dental caries in deciduous teeth was significantly higher in the Guiyu children than in Haojiang (62.5% vs. 53.9%). Blood Pb levels were negatively correlated with salivary sialic acids, in which IL-6 played as a mediator of the association between blood Pb levels and saliva sialic acid concentrations according to the mediation model. To our knowledge, this is the first report on the potential association between chronic Pb exposure and the anti-inflammatory ability of oral sialic acids among preschool children. These results suggest that the chronic Pb exposure can reduce salivary sialic acid levels, attenuate oral anti-inflammatory potential and increase the potential risk of dental caries in deciduous teeth among preschool children in an e-waste site.
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Affiliation(s)
- Ruikun Hou
- Laboratory of Environmental Medicine and Developmental Toxicology, Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Shantou University Medical College, Shantou 515041, Guangdong, China
| | - Xia Huo
- Laboratory of Environmental Medicine and Developmental Toxicology, Guangdong Key Laboratory of Environmental Pollution and Health, School of Environment, Jinan University, Guangzhou 510632, Guangdong, China
| | - Shaocheng Zhang
- Laboratory of Environmental Medicine and Developmental Toxicology, Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Shantou University Medical College, Shantou 515041, Guangdong, China
| | - Cheng Xu
- Laboratory of Environmental Medicine and Developmental Toxicology, Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Shantou University Medical College, Shantou 515041, Guangdong, China
| | - Yu Huang
- Laboratory of Environmental Medicine and Developmental Toxicology, Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Shantou University Medical College, Shantou 515041, Guangdong, China
| | - Xijing Xu
- Laboratory of Environmental Medicine and Developmental Toxicology, Guangdong Provincial Key Laboratory of Infectious Diseases and Molecular Immunopathology, Shantou University Medical College, Shantou 515041, Guangdong, China; Department of Cell Biology and Genetics, Shantou University Medical College, Shantou 515041, Guangdong, China.
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Sui Z, Sun H, Weng Y, Zhang X, Sun M, Sun R, Zhao B, Liang Z, Zhang Y, Li C, Zhang L. Quantitative proteomics analysis of deer antlerogenic periosteal cells reveals potential bioactive factors in velvet antlers. J Chromatogr A 2020; 1609:460496. [DOI: 10.1016/j.chroma.2019.460496] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 08/17/2019] [Accepted: 08/28/2019] [Indexed: 01/15/2023]
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Milcheva R, Janega P, Celec P, Petkova S, Hurniková Z, Izrael-Vlková B, Todorova K, Babál P. Accumulation of α-2,6-sialyoglycoproteins in the Muscle Sarcoplasm Due to Trichinella Sp. Invasion. Open Life Sci 2019; 14:470-481. [PMID: 33817183 PMCID: PMC7874827 DOI: 10.1515/biol-2019-0053] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 07/30/2019] [Indexed: 01/02/2023] Open
Abstract
The sialylation of the glycoproteins in skeletal muscle tissue is not well investigated, even though the essential role of the sialic acids for the proper muscular function has been proven by many researchers. The invasion of the parasitic nematode Trichinella spiralis in the muscles with subsequent formation of Nurse cell-parasite complex initiates increased accumulation of sialylated glycoproteins within the affected area of the muscle fiber. The aim of this study is to describe some details of the α-2,6-sialylation in invaded muscle cells. Asynchronous invasion with infectious T. spiralis larvae was experimentally induced in mice. The areas of the occupied sarcoplasm were reactive towards α-2,6-sialic acid specific Sambucus nigra agglutinin during the whole process of transformation to a Nurse cell.The cytoplasm of the developing Nurse cell reacted with Helix pomatia agglutinin, Arachis hypogea agglutinin and Vicia villosa lectin-B4 after neuraminidase pretreatment.Up-regulation of the enzyme ST6GalNAc1 and down-regulation of the enzyme ST6GalNAc3 were detected throughout the course of this study. The results from our study assumed accumulation of sialyl-Tn-Ag, 6`-sialyl lactosamine, SiA-α-2,6-Gal-β-1,3-GalNAc-α-Ser/Thr and Gal-β-1,3-GalNAc(SiA-α-2,6-)-α-1-Ser/Thr oligosaccharide structures into the occupied sarcoplasm. Further investigations in this domain will develop the understanding about the amazing adaptive capabilities of skeletal muscle tissue.
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Affiliation(s)
- Rositsa Milcheva
- Department of Pathology, IEMPAM, Bulgarian Academy of Sciences, ‘’Acad. G. Bonchev’’ Str. 25, 1113, Sofia, Bulgaria
- Institute of Experimental Morphology, Pathology and Anthropology with Museum (IEMPAM), Bulgarian Academy of Sciences, “Acad. G. Bonchev” Str. 25, 1113Sofia, Bulgaria
| | - Pavol Janega
- Department of Pathology, Faculty of Medicine, Comenius University in Bratislava, Sasinkova 4, 81372Bratislava, Slovakia
| | - Peter Celec
- Department of Molecular Biomedicine, Faculty of Medicine, Comenius University in Bratislava, Sasinkova 4, 81372Bratislava, Slovakia
| | - Svetlozara Petkova
- Institute of Experimental Morphology, Pathology and Anthropology with Museum (IEMPAM), Bulgarian Academy of Sciences, “Acad. G. Bonchev” Str. 25, 1113Sofia, Bulgaria
| | - Zuzana Hurniková
- Institute of Parasitology, Slovak Academy of Sciences, Hlinkova 3, 040 01Košice, Slovak Republic
| | - Barbora Izrael-Vlková
- Department of Molecular Biomedicine, Faculty of Medicine, Comenius University in Bratislava, Sasinkova 4, 81372Bratislava, Slovakia
| | - Katerina Todorova
- Institute of Experimental Morphology, Pathology and Anthropology with Museum (IEMPAM), Bulgarian Academy of Sciences, “Acad. G. Bonchev” Str. 25, 1113Sofia, Bulgaria
| | - Pavel Babál
- Department of Pathology, Faculty of Medicine, Comenius University in Bratislava, Sasinkova 4, 81372Bratislava, Slovakia
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Carrillo N, Malicdan MC, Huizing M. GNE Myopathy: Etiology, Diagnosis, and Therapeutic Challenges. Neurotherapeutics 2018; 15:900-914. [PMID: 30338442 PMCID: PMC6277305 DOI: 10.1007/s13311-018-0671-y] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
GNE myopathy, previously known as hereditary inclusion body myopathy (HIBM), or Nonaka myopathy, is a rare autosomal recessive muscle disease characterized by progressive skeletal muscle atrophy. It has an estimated prevalence of 1 to 9:1,000,000. GNE myopathy is caused by mutations in the GNE gene which encodes the rate-limiting enzyme of sialic acid biosynthesis. The pathophysiology of the disease is not entirely understood, but hyposialylation of muscle glycans is thought to play an essential role. The typical presentation is bilateral foot drop caused by weakness of the anterior tibialis muscles with onset in early adulthood. The disease slowly progresses over the next decades to involve skeletal muscles throughout the body, with relative sparing of the quadriceps until late stages of the disease. The diagnosis of GNE myopathy should be considered in young adults presenting with bilateral foot drop. Histopathologic findings on muscle biopsies include fiber size variation, atrophic fibers, lack of inflammation, and the characteristic "rimmed" vacuoles on modified Gomori trichome staining. The diagnosis is confirmed by the presence of pathogenic (mostly missense) mutations in both alleles of the GNE gene. Although there is no approved therapy for this disease, preclinical and clinical studies of several potential therapies are underway, including substrate replacement and gene therapy-based strategies. However, developing therapies for GNE myopathy is complicated by several factors, including the rare incidence of disease, limited preclinical models, lack of reliable biomarkers, and slow disease progression.
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Affiliation(s)
- Nuria Carrillo
- Medical Genetics Branch, National Human Genome Research Institute (NHGRI), National Institutes of Health, Bethesda, MD, 20892, USA.
| | - May C Malicdan
- Medical Genetics Branch, National Human Genome Research Institute (NHGRI), National Institutes of Health, Bethesda, MD, 20892, USA
| | - Marjan Huizing
- Medical Genetics Branch, National Human Genome Research Institute (NHGRI), National Institutes of Health, Bethesda, MD, 20892, USA
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Brasil S, Pascoal C, Francisco R, Marques-da-Silva D, Andreotti G, Videira PA, Morava E, Jaeken J, Dos Reis Ferreira V. CDG Therapies: From Bench to Bedside. Int J Mol Sci 2018; 19:ijms19051304. [PMID: 29702557 PMCID: PMC5983582 DOI: 10.3390/ijms19051304] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 04/14/2018] [Accepted: 04/21/2018] [Indexed: 12/20/2022] Open
Abstract
Congenital disorders of glycosylation (CDG) are a group of genetic disorders that affect protein and lipid glycosylation and glycosylphosphatidylinositol synthesis. More than 100 different disorders have been reported and the number is rapidly increasing. Since glycosylation is an essential post-translational process, patients present a large range of symptoms and variable phenotypes, from very mild to extremely severe. Only for few CDG, potentially curative therapies are being used, including dietary supplementation (e.g., galactose for PGM1-CDG, fucose for SLC35C1-CDG, Mn2+ for TMEM165-CDG or mannose for MPI-CDG) and organ transplantation (e.g., liver for MPI-CDG and heart for DOLK-CDG). However, for the majority of patients, only symptomatic and preventive treatments are in use. This constitutes a burden for patients, care-givers and ultimately the healthcare system. Innovative diagnostic approaches, in vitro and in vivo models and novel biomarkers have been developed that can lead to novel therapeutic avenues aiming to ameliorate the patients’ symptoms and lives. This review summarizes the advances in therapeutic approaches for CDG.
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Affiliation(s)
- Sandra Brasil
- Portuguese Association for Congenital Disorders of Glycosylation (CDG), Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2820-287 Lisboa, Portugal.
- Professionals and Patient Associations International Network (CDG & Allies-PPAIN), Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2820-287 Lisboa, Portugal.
| | - Carlota Pascoal
- Portuguese Association for Congenital Disorders of Glycosylation (CDG), Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2820-287 Lisboa, Portugal.
- Professionals and Patient Associations International Network (CDG & Allies-PPAIN), Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2820-287 Lisboa, Portugal.
- Research Unit on Applied Molecular Biosciences (UCIBIO), Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516 Lisboa, Portugal.
| | - Rita Francisco
- Portuguese Association for Congenital Disorders of Glycosylation (CDG), Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2820-287 Lisboa, Portugal.
- Professionals and Patient Associations International Network (CDG & Allies-PPAIN), Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2820-287 Lisboa, Portugal.
- Research Unit on Applied Molecular Biosciences (UCIBIO), Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516 Lisboa, Portugal.
| | - Dorinda Marques-da-Silva
- Portuguese Association for Congenital Disorders of Glycosylation (CDG), Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2820-287 Lisboa, Portugal.
- Professionals and Patient Associations International Network (CDG & Allies-PPAIN), Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2820-287 Lisboa, Portugal.
- Research Unit on Applied Molecular Biosciences (UCIBIO), Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516 Lisboa, Portugal.
| | - Giuseppina Andreotti
- Istituto di Chimica Biomolecolare-Consiglio Nazionale delle Ricerche (CNR), 80078 Pozzuoli, Italy.
| | - Paula A Videira
- Portuguese Association for Congenital Disorders of Glycosylation (CDG), Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2820-287 Lisboa, Portugal.
- Professionals and Patient Associations International Network (CDG & Allies-PPAIN), Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2820-287 Lisboa, Portugal.
- Research Unit on Applied Molecular Biosciences (UCIBIO), Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2829-516 Lisboa, Portugal.
| | - Eva Morava
- Professionals and Patient Associations International Network (CDG & Allies-PPAIN), Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2820-287 Lisboa, Portugal.
- Department of Clinical Genomics, Mayo Clinic, Rochester, MN 55905, USA.
| | - Jaak Jaeken
- Professionals and Patient Associations International Network (CDG & Allies-PPAIN), Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2820-287 Lisboa, Portugal.
- Center for Metabolic Diseases, Universitaire Ziekenhuizen (UZ) and Katholieke Universiteit (KU) Leuven, 3000 Leuven, Belgium.
| | - Vanessa Dos Reis Ferreira
- Portuguese Association for Congenital Disorders of Glycosylation (CDG), Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2820-287 Lisboa, Portugal.
- Professionals and Patient Associations International Network (CDG & Allies-PPAIN), Departamento Ciências da Vida, Faculdade de Ciências e Tecnologia, Universidade NOVA de Lisboa, 2820-287 Lisboa, Portugal.
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Abeln M, Borst KM, Cajic S, Thiesler H, Kats E, Albers I, Kuhn M, Kaever V, Rapp E, Münster-Kühnel A, Weinhold B. Sialylation Is Dispensable for Early Murine Embryonic Development in Vitro. Chembiochem 2017; 18:1305-1316. [PMID: 28374933 PMCID: PMC5502888 DOI: 10.1002/cbic.201700083] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Indexed: 12/19/2022]
Abstract
The negatively charged nonulose sialic acid (Sia) is essential for murine development in vivo. In order to elucidate the impact of sialylation on differentiation processes in the absence of maternal influences, we generated mouse embryonic stem cell (mESC) lines that lack CMP‐Sia synthetase (CMAS) and thereby the ability to activate Sia to CMP‐Sia. Loss of CMAS activity resulted in an asialo cell surface accompanied by an increase in glycoconjugates with terminal galactosyl and oligo‐LacNAc residues, as well as intracellular accumulation of free Sia. Remarkably, these changes did not impact intracellular metabolites or the morphology and transcriptome of pluripotent mESC lines. Moreover, the capacity of Cmas−/− mESCs for undirected differentiation into embryoid bodies, germ layer formation and even the generation of beating cardiomyocytes provides first and conclusive evidence that pluripotency and differentiation of mESC in vitro can proceed in the absence of (poly)sialoglycans.
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Affiliation(s)
- Markus Abeln
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625, Hannover, Germany
| | - Kristina M Borst
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625, Hannover, Germany
| | - Samanta Cajic
- Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstrasse 1, 39106, Magdeburg, Germany
| | - Hauke Thiesler
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625, Hannover, Germany
| | - Elina Kats
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625, Hannover, Germany
| | - Iris Albers
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625, Hannover, Germany
| | - Maike Kuhn
- TWINCORE Centre for Experimental and Clinical Infection Research GmbH, A joint venture between Hannover Medical School, Feodor-Lynen-Strasse 7, 30625, Hannover, Germany.,Helmholtz Centre for Infection Research, Inhoffenstrasse 7, 38124, Braunschweig, Germany
| | - Volkhard Kaever
- Research Core Unit Metabolomics, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625, Hannover, Germany
| | - Erdmann Rapp
- Max Planck Institute for Dynamics of Complex Technical Systems, Sandtorstrasse 1, 39106, Magdeburg, Germany.,glyXera GmbH, Leipziger Strasse 44, 39120, Magdeburg, Germany
| | - Anja Münster-Kühnel
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625, Hannover, Germany
| | - Birgit Weinhold
- Institute of Clinical Biochemistry, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625, Hannover, Germany
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11
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Pham ND, Pang PC, Krishnamurthy S, Wands AM, Grassi P, Dell A, Haslam SM, Kohler JJ. Effects of altered sialic acid biosynthesis on N-linked glycan branching and cell surface interactions. J Biol Chem 2017; 292:9637-9651. [PMID: 28424265 PMCID: PMC5465488 DOI: 10.1074/jbc.m116.764597] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Revised: 04/17/2017] [Indexed: 12/22/2022] Open
Abstract
GNE (UDP-GlcNAc 2-epimerase/ManNAc kinase) myopathy is a rare muscle disorder associated with aging and is related to sporadic inclusion body myositis, the most common acquired muscle disease of aging. Although the cause of sporadic inclusion body myositis is unknown, GNE myopathy is associated with mutations in GNE. GNE harbors two enzymatic activities required for biosynthesis of sialic acid in mammalian cells. Mutations to both GNE domains are linked to GNE myopathy. However, correlation between mutation-associated reductions in sialic acid production and disease severity is imperfect. To investigate other potential effects of GNE mutations, we compared sialic acid production in cell lines expressing wild type or mutant forms of GNE. Although we did not detect any differences attributable to disease-associated mutations, lectin binding and mass spectrometry analysis revealed that GNE deficiency is associated with unanticipated effects on the structure of cell-surface glycans. In addition to exhibiting low levels of sialylation, GNE-deficient cells produced distinct N-linked glycan structures with increased branching and extended poly-N-acetyllactosamine. GNE deficiency may affect levels of UDP-GlcNAc, a key metabolite in the nutrient-sensing hexosamine biosynthetic pathway, but this modest effect did not fully account for the change in N-linked glycan structure. Furthermore, GNE deficiency and glucose supplementation acted independently and additively to increase N-linked glycan branching. Notably, N-linked glycans produced by GNE-deficient cells displayed enhanced binding to galectin-1, indicating that changes in GNE activity can alter affinity of cell-surface glycoproteins for the galectin lattice. These findings suggest an unanticipated mechanism by which GNE activity might affect signaling through cell-surface receptors.
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Affiliation(s)
- Nam D Pham
- From the Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9038 and
| | - Poh-Choo Pang
- the Department of Life Sciences, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Soumya Krishnamurthy
- From the Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9038 and
| | - Amberlyn M Wands
- From the Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9038 and
| | - Paola Grassi
- the Department of Life Sciences, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Anne Dell
- the Department of Life Sciences, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Stuart M Haslam
- the Department of Life Sciences, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Jennifer J Kohler
- From the Department of Biochemistry, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9038 and
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12
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Bork K, Weidemann W, Berneck B, Kuchta M, Bennmann D, Thate A, Huber O, Gnanapragassam VS, Horstkorte R. The expression of sialyltransferases is regulated by the bioavailability and biosynthesis of sialic acids. Gene Expr Patterns 2017; 23-24:52-58. [DOI: 10.1016/j.gep.2017.03.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 03/14/2017] [Accepted: 03/23/2017] [Indexed: 11/25/2022]
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13
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Berger RP, Dookwah M, Steet R, Dalton S. Glycosylation and stem cells: Regulatory roles and application of iPSCs in the study of glycosylation-related disorders. Bioessays 2016; 38:1255-1265. [PMID: 27667795 PMCID: PMC5214967 DOI: 10.1002/bies.201600138] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Glycosylation refers to the co- and post-translational modification of protein and lipids by monosaccharides or oligosaccharide chains. The surface of mammalian cells is decorated by a heterogeneous and highly complex array of protein and lipid linked glycan structures that vary significantly between different cell types, raising questions about their roles in development and disease pathogenesis. This review will begin by focusing on recent findings that define roles for cell surface protein and lipid glycosylation in pluripotent stem cells and their functional impact during normal development. Then, we will describe how patient derived induced pluripotent stem cells are being used to model human diseases such as congenital disorders of glycosylation. Collectively, these studies indicate that cell surface glycans perform critical roles in human development and disease.
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Affiliation(s)
- Ryan P. Berger
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA
- Center for Molecular Medicine, University of Georgia, Athens, GA, USA
| | - Michelle Dookwah
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
| | - Richard Steet
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
| | - Stephen Dalton
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, USA
- Center for Molecular Medicine, University of Georgia, Athens, GA, USA
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14
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Wratil PR, Horstkorte R, Reutter W. Metabolic Glycoengineering with N-Acyl Side Chain Modified Mannosamines. Angew Chem Int Ed Engl 2016; 55:9482-512. [PMID: 27435524 DOI: 10.1002/anie.201601123] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2016] [Indexed: 12/14/2022]
Abstract
In metabolic glycoengineering (MGE), cells or animals are treated with unnatural derivatives of monosaccharides. After entering the cytosol, these sugar analogues are metabolized and subsequently expressed on newly synthesized glycoconjugates. The feasibility of MGE was first discovered for sialylated glycans, by using N-acyl-modified mannosamines as precursor molecules for unnatural sialic acids. Prerequisite is the promiscuity of the enzymes of the Roseman-Warren biosynthetic pathway. These enzymes were shown to tolerate specific modifications of the N-acyl side chain of mannosamine analogues, for example, elongation by one or more methylene groups (aliphatic modifications) or by insertion of reactive groups (bioorthogonal modifications). Unnatural sialic acids are incorporated into glycoconjugates of cells and organs. MGE has intriguing biological consequences for treated cells (aliphatic MGE) and offers the opportunity to visualize the topography and dynamics of sialylated glycans in vitro, ex vivo, and in vivo (bioorthogonal MGE).
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Affiliation(s)
- Paul R Wratil
- Institut für Laboratoriumsmedizin, Klinische Chemie und Pathobiochemie, Charité-Universitätsmedizin Berlin, Arnimallee 22, 14195, Berlin, Germany.
| | - Rüdiger Horstkorte
- Institut für Physiologische Chemie, Martin-Luther-Universität Halle-Wittenberg, Hollystrasse 1, 06114, Halle, Germany.
| | - Werner Reutter
- Institut für Laboratoriumsmedizin, Klinische Chemie und Pathobiochemie, Charité-Universitätsmedizin Berlin, Arnimallee 22, 14195, Berlin, Germany
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15
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Wratil PR, Horstkorte R, Reutter W. Metabolisches Glykoengineering mitN-Acyl-Seiten- ketten-modifizierten Mannosaminen. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201601123] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Paul R. Wratil
- Institut für Laboratoriumsmedizin, Klinische Chemie und Pathobiochemie; Charité - Universitätsmedizin Berlin; Arnimallee 22 14195 Berlin Deutschland
| | - Rüdiger Horstkorte
- Institut für Physiologische Chemie; Martin-Luther-Universität Halle-Wittenberg; Hollystraße 1 06114 Halle Deutschland
| | - Werner Reutter
- Institut für Laboratoriumsmedizin, Klinische Chemie und Pathobiochemie; Charité - Universitätsmedizin Berlin; Arnimallee 22 14195 Berlin Deutschland
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16
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Willems AP, van Engelen BGM, Lefeber DJ. Genetic defects in the hexosamine and sialic acid biosynthesis pathway. Biochim Biophys Acta Gen Subj 2015; 1860:1640-54. [PMID: 26721333 DOI: 10.1016/j.bbagen.2015.12.017] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Revised: 12/18/2015] [Accepted: 12/19/2015] [Indexed: 01/10/2023]
Abstract
BACKGROUND Congenital disorders of glycosylation are caused by defects in the glycosylation of proteins and lipids. Classically, gene defects with multisystem disease have been identified in the ubiquitously expressed glycosyltransferases required for protein N-glycosylation. An increasing number of defects are being described in sugar supply pathways for protein glycosylation with tissue-restricted clinical symptoms. SCOPE OF REVIEW In this review, we address the hexosamine and sialic acid biosynthesis pathways in sugar metabolism. GFPT1, PGM3 and GNE are essential for synthesis of nucleotide sugars uridine diphosphate N-acetylglucosamine (UDP-GlcNAc) and cytidine-5'-monophospho-N-acetylneuraminic acid (CMP-sialic acid) as precursors for various glycosylation pathways. Defects in these enzymes result in contrasting clinical phenotypes of congenital myasthenia, immunodeficiency or adult-onset myopathy, respectively. We therefore discuss the biochemical mechanisms of known genetic defects in the hexosamine and CMP-sialic acid synthesis pathway in relation to the clinical phenotypes. MAJOR CONCLUSIONS Both UDP-GlcNAc and CMP-sialic acid are important precursors for diverse protein glycosylation reactions and for conversion into other nucleotide-sugars. Defects in the synthesis of these nucleotide sugars might affect a wide range of protein glycosylation reactions. Involvement of multiple glycosylation pathways might contribute to disease phenotype, but the currently available biochemical information on sugar metabolism is insufficient to understand why defects in these pathways present with tissue-specific phenotypes. GENERAL SIGNIFICANCE Future research on the interplay between sugar metabolism and different glycosylation pathways in a tissue- and cell-specific manner will contribute to elucidation of disease mechanisms and will create new opportunities for therapeutic intervention. This article is part of a Special Issue entitled "Glycans in personalised medicine" Guest Editor: Professor Gordan Lauc.
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Affiliation(s)
- Anke P Willems
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Centre, Box 9101, 6500 HB Nijmegen, The Netherlands; Department of Laboratory Medicine, Translational Metabolic Laboratory, Radboudumc Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands
| | - Baziel G M van Engelen
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Centre, Box 9101, 6500 HB Nijmegen, The Netherlands
| | - Dirk J Lefeber
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Centre, Box 9101, 6500 HB Nijmegen, The Netherlands; Department of Laboratory Medicine, Translational Metabolic Laboratory, Radboudumc Institute for Molecular Life Sciences, Radboud University Medical Center, 6525 GA Nijmegen, The Netherlands.
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17
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Lange-Consiglio A, Accogli G, Cremonesi F, Desantis S. Cell Surface Glycan Changes in the Spontaneous Epithelial-Mesenchymal Transition of Equine Amniotic Multipotent Progenitor Cells. Cells Tissues Organs 2015; 200:212-26. [PMID: 26337136 DOI: 10.1159/000433420] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/19/2015] [Indexed: 11/19/2022] Open
Abstract
Amniotic epithelial cells (AECs) spontaneously transform into amniotic mesenchymal cells (AMCs) in vitro during cell culture. Glycocalyx was analyzed to identify the glycan pattern in AECs, AMCs and epithelial-mesenchymal transdifferentiated cells (EMTCs). Pure cell cultures were derived using cloned AEC and AMC cell lines obtained by the dilution technique from amniotic membranes. Mesenchymal cells generated by differentiation of clonal epithelial cells were considered transdifferentiated. Immunocytoscreen, in vitro multipotent differentiation and molecular characterization of EMTCs were performed. In combination with saponification and sialidase digestion, a panel of 12 lectins was used to analyze the glycan pattern of AEC, AMC and EMTC glycocalyx. Cytokeratin cell markers were lost in EMTCs and typical mesenchymal markers, such as vimentin, appeared. These cells retained their differentiation potential. Lectin histochemistry revealed a cell-specific glycan profile. Galactose (Gal)β1,4GlcNAc, Neu5Acα2,6Gal/GalNAc and N-acetyl neuraminic (sialic) acid (NeuNAc)α2,3Galβ1,3(±NeuNAcα2,6)GalNAc were highly expressed on the surface of all the amniotic cell cultures. AECs expressed asialoglycans with terminal GalNAc and GlcNAc. More highly mannosylated N-linked glycans and NeuNAcα2,3Galβ1,3GalNAc in O-linked glycans were expressed by EMTCs, but these cells had fewer glycans ending with fucose (Fuc), Gal, GlcNAc and GalNAc than AECs. GlcNAc- and GalNAc-terminating glycans were similarly expressed on the glycocalyx of the mesenchymal cell populations (EMTCs and AMCs). These results demonstrate for the first time that the spontaneous epithelial-mesenchymal transition (EMT) of equine amnion cells is characterized by cell surface glycan remodeling and that glycosylation changes result in a cell type-specific glycan profile. The glycopattern of equine amnion spontaneous EMTCs differs from EMT of tumoral cells.
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Affiliation(s)
- Anna Lange-Consiglio
- Reproduction Unit, Large Animal Hospital, Universitx00E0; degli Studi di Milano, Lodi, Italy
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18
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Singh R, Arya R. GNE Myopathy and Cell Apoptosis: A Comparative Mutation Analysis. Mol Neurobiol 2015; 53:3088-3101. [PMID: 25976366 DOI: 10.1007/s12035-015-9191-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Accepted: 04/22/2015] [Indexed: 10/23/2022]
Abstract
In a number of genetic disorders such as GNE myopathy, it is not clear how mutations in target genes result in disease phenotype. GNE myopathy is a progressive neuro-degenerative disorder associated with homozygous or compound heterozygous missense mutations in either epimerase or kinase domain of UDP-GlcNAc 2-epimerase/ManNAc kinase (GNE). This bifunctional enzyme catalyses the rate limiting step in sialic acid biosynthesis. Many mechanisms have been suggested as possible cause of muscle degeneration. These include hyposialylation of critical proteins, defects in cytoskeletal network, sarcomere organization and apoptosis. In order to elucidate the role of GNE in cell apoptosis, we have used HEK cell-based model system overexpressing pathologically relevant GNE mutations. These cells display a reduction in the levels of sialic acid-bound glycoconjugates. These mutants GNE overexpressing cells have defect in cell proliferation as compared to vector or wild-type GNE (wtGNE) controls. Moreover, effect of different GNE mutations on cell apoptosis was also observed using staining with annexin V-FITC and TUNEL assay. The downstream apoptosis signalling pathway involving activation of caspases and increased PARP cleavage were observed in all GNE mutant cell lines. In addition, morpho-structural changes in mitochondria in cells overexpressing different GNE mutants were noticed by transmission electron microscopy, and mitochondrial transmembrane potential was found to be altered in absence of functional GNE. Our results clearly indicate role of GNE in mitochondria-dependent cell apoptosis and provide insights into the pathomechanism of GNE myopathy.
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Affiliation(s)
- Reema Singh
- School of Biotechnology, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Ranjana Arya
- School of Biotechnology, Jawaharlal Nehru University, New Delhi, 110067, India.
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19
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N-Acetylmannosamine Improves Object Recognition and Hippocampal Cell Proliferation in Middle-Aged Mice. Biosci Biotechnol Biochem 2014; 76:2249-54. [DOI: 10.1271/bbb.120536] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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20
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Daya A, Vatine GD, Becker-Cohen M, Tal-Goldberg T, Friedmann A, Gothilf Y, Du SJ, Mitrani-Rosenbaum S. Gne depletion during zebrafish development impairs skeletal muscle structure and function. Hum Mol Genet 2014; 23:3349-61. [PMID: 24488768 DOI: 10.1093/hmg/ddu045] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
GNE Myopathy is a rare recessively inherited neuromuscular disorder caused by mutations in the GNE gene, which codes for the key enzyme in the metabolic pathway of sialic acid synthesis. The process by which GNE mutations lead to myopathy is not well understood. By in situ hybridization and gne promoter-driven fluorescent transgenic fish generation, we have characterized the spatiotemporal expression pattern of the zebrafish gne gene and have shown that it is highly conserved compared with the human ortholog. We also show the deposition of maternal gne mRNA and maternal GNE protein at the earliest embryonic stage, emphasizing the critical role of gne in embryonic development. Injection of morpholino (MO)-modified antisense oligonucleotides specifically designed to knockdown gne, into one-cell embryos lead to a variety of phenotypic severity. Characterization of the gne knockdown morphants showed a significantly reduced locomotor activity as well as distorted muscle integrity, including a reduction in the number of muscle myofibers, even in mild or intermediate phenotype morphants. These findings were further confirmed by electron microscopy studies, where large gaps between sarcolemmas were visualized, although normal sarcomeric structures were maintained. These results demonstrate a critical novel role for gne in embryonic development and particularly in myofiber development, muscle integrity and activity.
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Affiliation(s)
- Alon Daya
- Goldyne Savad Institute of Gene Therapy, Hadassah Hebrew University Medical Center, Jerusalem 91240, Israel, School of Marine Sciences, Ruppin Academic Center, Michmoret 40297, Israel
| | - Gad David Vatine
- Department of Neurobiology, The George S. Wise Faculty of Life Sciences and
| | - Michal Becker-Cohen
- Goldyne Savad Institute of Gene Therapy, Hadassah Hebrew University Medical Center, Jerusalem 91240, Israel
| | - Tzukit Tal-Goldberg
- Goldyne Savad Institute of Gene Therapy, Hadassah Hebrew University Medical Center, Jerusalem 91240, Israel
| | - Adam Friedmann
- School of Marine Sciences, Ruppin Academic Center, Michmoret 40297, Israel
| | - Yoav Gothilf
- Department of Neurobiology, The George S. Wise Faculty of Life Sciences and Sagol School of Neuroscience, Tel-Aviv University, Tel Aviv 69978, Israel
| | - Shao Jun Du
- Institute of Marine and Environmental Technology, Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, MD 21201, USA
| | - Stella Mitrani-Rosenbaum
- Goldyne Savad Institute of Gene Therapy, Hadassah Hebrew University Medical Center, Jerusalem 91240, Israel,
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The key enzyme of the sialic acid metabolism is involved in embryoid body formation and expression of marker genes of germ layer formation. Int J Mol Sci 2013; 14:20555-63. [PMID: 24129184 PMCID: PMC3821630 DOI: 10.3390/ijms141020555] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2013] [Revised: 09/24/2013] [Accepted: 09/27/2013] [Indexed: 12/31/2022] Open
Abstract
The bi-functional enzyme UDP-N-acetyl-2-epimerase/N-acetylmannosamine kinase (GNE) is the key enzyme of the sialic acid biosynthesis. Sialic acids are negatively charged nine carbon amino sugars and are found on most glycoproteins and many glycolipids in terminal positions, where they are involved in a variety of biological important molecular interactions. Inactivation of the GNE by homologous recombination results in early embryonic lethality in mice. Here, we report that GNE-deficient embryonic stem cells express less differentiation markers compared to wild-type embryonic stem cells. As a result, GNE-deficient embryonic stem cells fail to form proper embryoid bodies (EB) within the first day of culture. However, when culturing these cells in the presence of sialic acids for three days, also GNE-deficient embryonic stem cells form normal EBs. In contrast, when culturing these cells in sialic acid reduced medium, GNE-deficient embryonic stem cells proliferate faster and form larger EBs without any change in the expression of markers of the germ layers.
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22
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Stimulation of human peripheral blood mononuclear cells by the sialic acid precursor N-propanoylmannosamine. Glycoconj J 2013; 30:813-8. [DOI: 10.1007/s10719-013-9485-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Revised: 05/23/2013] [Accepted: 06/17/2013] [Indexed: 01/08/2023]
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23
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Artificial and natural sialic acid precursors influence the angiogenic capacity of human umbilical vein endothelial cells. Molecules 2013; 18:2571-86. [PMID: 23442933 PMCID: PMC6269824 DOI: 10.3390/molecules18032571] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Revised: 02/06/2013] [Accepted: 02/19/2013] [Indexed: 02/02/2023] Open
Abstract
N-acetylneuraminic acid (Neu5Ac) represents the most common terminal carbohydrate residue in many mammalian glycoconjugates and is directly involved in a number of different physiological as well as pathological cellular processes. Endogenous sialic acids derive from the biosynthetic precursor molecule N-acetyl-D-mannosamine (ManNAc). Interestingly, N-acyl-analogues of D-mannosamine (ManN) can also be incorporated and converted into corresponding artificial sialic acids by eukaryotic cells. Within this study, we optimized a protocol for the chemical synthesis of various peracetylated ManN derivatives resulting in yields of approximately 100%. Correct molecular structures of the obtained products ManNAc, N-propanoyl-ManN (ManNProp) and N-butyl-ManN (ManNBut) were verified by GC-, ESI-MS- and NMR-analyses. By applying these substances to human umbilical vein endothelial cells (HUVECs), we could show that each derivative was metabolized to the corresponding N-acylneuraminic acid variant and subsequently incorporated into nascent glycoproteins. To investigate whether natural and/or artificial sialic acid precursors are able to modulate the angiogenic capacity of HUVECs, a spheroid assay was performed. By this means, an increase in total capillary length has been observed when cells incorporated N-butylneuraminic acid (Neu5But) into their glycoconjugates. In contrast, the natural precursor ManNAc inhibited the growth of capillaries. Thus, sialic acid precursors may represent useful agents to modulate blood vessel formation.
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24
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Amano M, Eriksson H, Manning JC, Detjen KM, André S, Nishimura SI, Lehtiö J, Gabius HJ. Tumour suppressor p16(INK4a) - anoikis-favouring decrease in N/O-glycan/cell surface sialylation by down-regulation of enzymes in sialic acid biosynthesis in tandem in a pancreatic carcinoma model. FEBS J 2013; 279:4062-80. [PMID: 22943525 DOI: 10.1111/febs.12001] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Tumour suppressor p16(INK4a) is known to exert cell-cycle control via cyclin-dependent kinases. An emerging aspect of its functionality is the orchestrated modulation of N/O-glycosylation and galectin expression to induce anoikis in human Capan-1 pancreatic carcinoma cells. Using chemoselective N/O-glycan enrichment technology (glycoblotting) and product characterization, we first verified a substantial decrease in sialylation. Tests combining genetic (i.e. transfection with α2,6-sialyltransferase-specific cDNA) or metabolic (i.e. medium supplementation with N-acetylmannosamine to track down a bottleneck in sialic acid biosynthesis) engineering with cytofluorometric analysis of lectin binding indicated a role of limited substrate availability, especially for α2,6-sialylation, which switches off reactivity for anoikis-triggering homodimeric galectin-1. Quantitative MS analysis of protein level changes confirmed an enhanced galectin-1 presence along with an influence on glycosyltransferases (β1,4-galactosyltransferase-IV, α2,3-sialyltransferase-I) and detected p16(INK4a) -dependent down-regulation of two enzymes in the biosynthesis pathway for sialic acid [i.e. the bifunctional UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE) and N-acetylneuraminic acid 9-phosphate synthase] (P < 0.001). By contrast, quantitative assessment for the presence of nuclear CMP-N-acetylneuraminic acid synthase (which is responsible for providing the donor for enzymatic sialylation that also acts as feedback inhibitor of the epimerase activity of GNE) revealed a trend for an increase. Partial restoration of sialylation in GNE-transfected cells supports the implied role of sialic acid availability for the glycophenotype. Fittingly, the extent of anoikis was reduced in double-transfected (p16(INK4a) /GNE) cells. Thus, a second means of modulating cell reactivity to the growth effector galectin-1 is established in addition to the common route of altering α2,6-sialyltransferase expression: regulating enzymes of the pathway for sialic acid biosynthesis.
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Affiliation(s)
- Maho Amano
- Field of Drug Discovery Research, Graduate School of Life Sciences, Hokkaido University, Sapporo, Japan.
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Hinderlich S, Weidemann W, Yardeni T, Horstkorte R, Huizing M. UDP-GlcNAc 2-Epimerase/ManNAc Kinase (GNE): A Master Regulator of Sialic Acid Synthesis. Top Curr Chem (Cham) 2013; 366:97-137. [PMID: 23842869 DOI: 10.1007/128_2013_464] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase is the key enzyme of sialic acid biosynthesis in vertebrates. It catalyzes the first two steps of the cytosolic formation of CMP-N-acetylneuraminic acid from UDP-N-acetylglucosamine. In this review we give an overview of structure, biochemistry, and genetics of the bifunctional enzyme and its complex regulation. Furthermore, we will focus on diseases related to UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase.
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Affiliation(s)
- Stephan Hinderlich
- Department of Life Sciences and Technology, Beuth Hochschule für Technik Berlin, University of Applied Sciences, Berlin, Germany,
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Kemmner W, Kessel P, Sanchez-Ruderisch H, Möller H, Hinderlich S, Schlag PM, Detjen K. Loss of UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE) induces apoptotic processes in pancreatic carcinoma cells. FASEB J 2011; 26:938-46. [PMID: 22049060 DOI: 10.1096/fj.11-186700] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Early invasive growth and metastasis are features of pancreatic cancer that rely on its resistance to anoikis, an apoptosis program activated on loss of matrix anchorage. How anoikis is regulated is unclear. UDP-N-acetylglucosamine-2-epimerase/N-acetylmannosamine-kinase (GNE) was silenced, or p16 was overexpressed, in human pancreatic carcinoma cells. Gene expression profiling, enzymatic assays, Western blotting, and cell cycle analysis were conducted. Silencing of GNE, the key enzyme of sialic acid biosynthesis, sensitizes pancreatic cancer cells to anoikis. Accordingly, we observed a loss of GNE enzyme activity in cells, which became anoikis susceptible after transfection with the tumor suppressor p16. Similarly, studies of another cell line with low GNE activity revealed strong anoikis susceptibility, confirming the association of low GNE activity and anoikis susceptibility. Gene expression profiling demonstrated that the loss of GNE triggered the transcriptional activation of the ATF4-ATF3-CHOP pathway, leading to apoptosis in the framework of the unfolded protein response. In silico analysis showed that GNE up-regulation occurred predominantly in pancreatic cancer but also in other malignancies. Delineation of GNE-dependent signaling pathways may provide targets that control anchorage dependence and/or restore drug efficacy, which is of utmost relevance for the treatment of pancreatic cancer.
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Affiliation(s)
- Wolfgang Kemmner
- Research Group Surgical Oncology, Experimental and Clinical Research Center, Charité Campus Buch, Berlin, Germany.
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Weidemann W, Reinhardt A, Thate A, Horstkorte R. Biochemical characterization of the M712T-mutation of the UDP-N-acetylglucosamine 2-epimerase/N-acetyl-mannosaminekinase in hereditary inclusion body myopathy. Neuromuscul Disord 2011; 21:824-31. [PMID: 21873062 DOI: 10.1016/j.nmd.2011.06.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2011] [Revised: 06/08/2011] [Accepted: 06/10/2011] [Indexed: 01/01/2023]
Abstract
Hereditary inclusion body myopathy is a neuromuscular disorder characterized by muscle weakness with a late onset and slow progression. It is caused by mutations of the gene encoding UDP-N-acetylglucosamine-2-epimerase/N-acetylmannosamine kinase (GNE). One of the most frequent mutations is an exchange of methionine to threonine at position 712 (M712T). Here we analyzed wildtype (wt) and M712T-mutated (M712T) GNE. We identified threonine 712 as an additional possible phosphorylation site and found by two-dimensional gel-electrophoresis a lower isoelectric point compared to wt-GNE. This lower isoelectric point could be partially reversed back to the wildtype isoelectric point after treatment with protein phosphatase. Furthermore, in contrast to wt-GNE, a significant fraction of M712T-GNE was in the insoluble fraction. Finally, by using bimolecular fluorescence complementation we demonstrate that the M712T mutation does not disrupt the formation of GNE-oligomers.
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Affiliation(s)
- Wenke Weidemann
- Institute of Physiological Chemistry, Martin-Luther University of Halle-Wittenberg, Hollystr. 1, D-06114 Halle, Germany
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28
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GNE is involved in the early development of skeletal and cardiac muscle. PLoS One 2011; 6:e21389. [PMID: 21731727 PMCID: PMC3123316 DOI: 10.1371/journal.pone.0021389] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Accepted: 05/26/2011] [Indexed: 12/31/2022] Open
Abstract
UDP-N-acetylglucosamine 2 epimerase/N-acetylmannosamime kinase (GNE) is a bifunctional enzyme which catalyzes the two key sequential steps in the biosynthetic pathway of sialic acid, the most abundant terminal monosaccharide on glycoconjugates of eukaryotic cells. GNE knock out (GNE KO) mice are embryonically lethal at day E8.5. Although the role of GNE in the sialic pathway has been well established as well as the importance of sialylation in many diverse biological pathways, less is known about the involvement of GNE in muscle development. To address this issue we have studied the role of GNE during in vitro embryogenesis by comparing the developmental profile in culture of embryonic stem cells (ES) from wild type and from GNE KO E3.5 mice embryos, during 45 days. Neuronal cells appeared rarely in GNE KO ES cultures and did not reach an advanced differentiated stage. Although primary cardiac cells appeared at the same time in both normal and GNE KO ES cultures, GNE KO cardiac cells degraded very soon and their beating capacity decayed rapidly. Furthermore very rare skeletal muscle committed cells were detected in the GNE KO ES cultures at any stage of differentiation, as assessed by analysis of the expression of either Pax7, MyoD and MyHC markers. Beyond the supporting evidence that GNE plays an important role in neuronal cell and brain development, these results show that GNE is strongly involved in cardiac tissue and skeletal muscle early survival and organization. These findings could open new avenues in the understanding of muscle function mechanisms in health and in disease.
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de Mendoza A, Ruiz-Trillo I. The mysterious evolutionary origin for the GNE gene and the root of bilateria. Mol Biol Evol 2011; 28:2987-91. [PMID: 21616910 DOI: 10.1093/molbev/msr142] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Phylogenomic analyses have revealed several important metazoan clades, such as the Ecdysozoa and the Lophotrochozoa. However, the phylogenetic positions of a few taxa, such as ctenophores, chaetognaths, acoelomorphs, and Xenoturbella, remain contentious. Thus, the findings of qualitative markers or "rare genomic changes" seem ideal to independently test previous phylogenetic hypotheses. We here describe a rare genomic change, the presence of the gene UDP-GlcNAc 2-epimerase/N-acetylmannosamine kinase (GNE). We show that GNE is encoded in the genomes of deuterostomes, acoelomorphs and Xenoturbella, whereas it is absent in protostomes and nonbilaterians. Moreover, the GNE has a complex evolutionary origin involving unique lateral gene transfer events and/or extensive hidden paralogy for each protein domain. However, rather than using GNE as a phylogenetic character, we argue that rare genomic changes such as the one presented here should be used with caution.
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Affiliation(s)
- Alex de Mendoza
- Departament de Genètica, Universitat de Barcelona, Barcelona, Spain
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30
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Möller H, Böhrsch V, Lucka L, Hackenberger CPR, Hinderlich S. Efficient metabolic oligosaccharide engineering of glycoproteins by UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE) knock-down. MOLECULAR BIOSYSTEMS 2011; 7:2245-51. [PMID: 21584309 DOI: 10.1039/c1mb05059a] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Improving the accessibility and functions of therapeutic and diagnostic glycoproteins is one of the major goals of glycobiotechnology. Here we present that stable knock-down of UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase (GNE), the key enzyme in the sialic acid biosynthetic pathway, dramatically increases incorporation of N-acetylmannosamine analogues into glycoproteins of HEK293 cells. By means of these GNE-deficient cells highly sialylated glycoproteins can efficiently be decorated with reactive functional groups, which can be employed in bioorthogonal functionalization strategies for fluorescence labelling or biotinylation.
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Affiliation(s)
- Heinz Möller
- Beuth Hochschule für Technik Berlin (University of Applied Sciences), Department of Life Sciences and Technology, Seestrasse 64, 13347 Berlin, Germany
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31
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Wong DCF, Wong NSC, Goh JSY, May LM, Yap MGS. Profiling of N-glycosylation gene expression in CHO cell fed-batch cultures. Biotechnol Bioeng 2010; 107:516-28. [PMID: 20521304 DOI: 10.1002/bit.22828] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Danny Chee Furng Wong
- Bioprocessing Technology Institute, A*STAR (Agency for Science, Technology and Research), 20 Biopolis Way, #06-01, Singapore 138668, Singapore
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Horstkorte R, Reinke S, Bauer C, Reutter W, Kontou M. N-Propionylmannosamine-induced over-expression and secretion of thioredoxin leads to neurite outgrowth of PC12 cells. Biochem Biophys Res Commun 2010; 395:296-300. [DOI: 10.1016/j.bbrc.2010.03.113] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2010] [Accepted: 03/17/2010] [Indexed: 10/19/2022]
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Freeze HH, Sharma V. Metabolic manipulation of glycosylation disorders in humans and animal models. Semin Cell Dev Biol 2010; 21:655-62. [PMID: 20363348 DOI: 10.1016/j.semcdb.2010.03.011] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2009] [Revised: 03/24/2010] [Accepted: 03/26/2010] [Indexed: 12/11/2022]
Abstract
In the last decade, over 40 inherited human glycosylation disorders were identified. Most patients have hypomorphic, rather than null alleles. The phenotypic spectrum is broad and most of the disorders affect embryonic and early post-natal development; a few appear in adult life. Some deficiencies can be treated with simple dietary sugar (monosaccharide) supplements. Here we focus on four glycosylation disorders that have been treated with supplements in patients or in model systems, primarily the mouse. Surprisingly, small differences in the amount of exogenous sugar have a major impact on the diseases in specific cells or organs while others are unaffected. The underlying mechanisms are mostly unknown, but changes in the contributions of the de novo, salvage and dietary pathways may contribute to the beneficial outcome. Clearly, the metabolic chart is not flat; all arrows are not equally robust at all points of time and space. This metabolic perspective may help explain some of these observations and guide the development of other vertebrate models of glycosylation disorders that can respond to dietary manipulation.
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Affiliation(s)
- Hudson H Freeze
- Sanford-Burnham Medical Research Institute, La Jolla, CA 92037, USA.
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