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Zhang Y, Wu D, Yu T, Liu Y, Zhao C, Xue R. Prognostic value of TMTC1 in pan-cancer analysis. Heliyon 2024; 10:e38308. [PMID: 39397950 PMCID: PMC11471174 DOI: 10.1016/j.heliyon.2024.e38308] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 09/20/2024] [Accepted: 09/22/2024] [Indexed: 10/15/2024] Open
Abstract
Background Transmembrane and tetratricopeptide repeat containing 1 (TMTC1) is a recently discovered enzyme involved in the O-mannosylation of cadherins and protocadherins. It has been implicated in various types of cancer, but the overall prognostic significance of TMTC1 in pan-cancer and its potential as an immunotherapeutic target remain unclear. Methods We applied various bioinformatics methods to investigate the potential oncogenic roles of TMTC1 using public databases. This analysis involved examining the expression, prognosis, genetic alterations, immune infiltration, immunotherapy response, drug sensitivity, and regulatory mechanisms of the TMTC1 gene in diverse cancer types. Results In this study, we observed that TMTC1 expression is reduced in 19 types of cancer (ACC, BLCA, BRCA, CESC, COAD, ESCA, GBM, KICH, KIRC, KIRP, LAML, LUAD, LUSC, PRAD, READ, STAD, THCA, UCEC, and UCS) compared to normal tissues. Conversely, TMTC1 expression is elevated in OV and PAAD relative to normal tissues. Moreover, our analysis revealed that high expression of TMTC1 was associated with worse overall survival (OS) outcomes in patients with ACC, BLCA, COAD, GBM, KIRP, OV, STAD, and UCEC, but better OS outcomes in patients with CESC, KIRC, LUSC, and PAAD. Notably, patients with TMTC1 mutations or deep deletions demonstrated longer OS, while those with TMTC1 amplification showed shorter OS. There was a significant correlation between the expression level of TMTC1 and the infiltration of cancer-associated fibroblasts (CAFs) and endothelial cells. Using data from six real-world immunotherapy cohorts of BLCA, SKCM and RCC, we discovered that high TMTC1 expression was associated with better OS or progression-free survival (PFS). Lastly, through TMTC1-related gene enrichment analysis, some biological processes and pathways were found to be significantly enriched, such as vascular endothelial growth factor receptor signaling pathway and ECM-receptor interaction. Conclusions Our study demonstrates the prognostic significance of TMTC1 in pan-cancer and highlights its potential as an immunotherapeutic target.
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Affiliation(s)
- Ying Zhang
- The International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Labouratory of Embryo Original Diseases, 200030, Shanghai, China
- Institute of Birth Defects and Rare Diseases, School of Medicine, Shanghai Jiao Tong University, 200030, Shanghai, China
| | - Dan Wu
- Department of Obstrics and Gynecology, The First People's Hospital of Jiande, Hangzhou, China
| | - Tiantian Yu
- The International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Labouratory of Embryo Original Diseases, 200030, Shanghai, China
- Institute of Birth Defects and Rare Diseases, School of Medicine, Shanghai Jiao Tong University, 200030, Shanghai, China
| | - Yao Liu
- The International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Labouratory of Embryo Original Diseases, 200030, Shanghai, China
- Institute of Birth Defects and Rare Diseases, School of Medicine, Shanghai Jiao Tong University, 200030, Shanghai, China
| | - Chunbo Zhao
- Department of Obstrics and Gynecology, The First People's Hospital of Jiande, Hangzhou, China
| | - Ruihong Xue
- The International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
- Shanghai Key Labouratory of Embryo Original Diseases, 200030, Shanghai, China
- Institute of Birth Defects and Rare Diseases, School of Medicine, Shanghai Jiao Tong University, 200030, Shanghai, China
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Povolo L, Tian W, Vakhrushev SY, Halim A. Global View of Domain-Specific O-Linked Mannose Glycosylation in Glycoengineered Cells. Mol Cell Proteomics 2024; 23:100796. [PMID: 38851451 PMCID: PMC11292533 DOI: 10.1016/j.mcpro.2024.100796] [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: 01/16/2024] [Revised: 06/03/2024] [Accepted: 06/05/2024] [Indexed: 06/10/2024] Open
Abstract
Protein O-linked mannose (O-Man) glycosylation is an evolutionary conserved posttranslational modification that fulfills important biological roles during embryonic development. Three nonredundant enzyme families, POMT1/POMT2, TMTC1-4, and TMEM260, selectively coordinate the initiation of protein O-Man glycosylation on distinct classes of transmembrane proteins, including α-dystroglycan, cadherins, and plexin receptors. However, a systematic investigation of their substrate specificities is lacking, in part due to the ubiquitous expression of O-Man glycosyltransferases in cells, which precludes analysis of pathway-specific O-Man glycosylation on a proteome-wide scale. Here, we apply a targeted workflow for membrane glycoproteomics across five human cell lines to extensively map O-Man substrates and genetically deconstruct O-Man initiation by individual and combinatorial knockout of O-Man glycosyltransferase genes. We established a human cell library for the analysis of substrate specificities of individual O-Man initiation pathways by quantitative glycoproteomics. Our results identify 180 O-Man glycoproteins, demonstrate new protein targets for the POMT1/POMT2 pathway, and show that TMTC1-4 and TMEM260 pathways widely target distinct Ig-like protein domains of plasma membrane proteins involved in cell-cell and cell-extracellular matrix interactions. The identification of O-Man on Ig-like folds adds further knowledge on the emerging concept of domain-specific O-Man glycosylation which opens for functional studies of O-Man-glycosylated adhesion molecules and receptors.
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Affiliation(s)
- Lorenzo Povolo
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen N, Denmark
| | - Weihua Tian
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen N, Denmark
| | - Sergey Y Vakhrushev
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen N, Denmark
| | - Adnan Halim
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen N, Denmark.
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3
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Cerdà P, Castillo SD, Aguilera C, Iriarte A, Rocamora JL, Larrinaga AM, Viñals F, Graupera M, Riera-Mestre A. New genetic drivers in hemorrhagic hereditary telangiectasia. Eur J Intern Med 2024; 119:99-108. [PMID: 37689549 DOI: 10.1016/j.ejim.2023.08.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 08/21/2023] [Accepted: 08/24/2023] [Indexed: 09/11/2023]
Abstract
BACKGROUND Hereditary hemorrhagic telangiectasia (HHT) is a rare vascular disease inherited in an autosomal dominant manner. Disease-causing variants in endoglin (ENG) and activin A receptor type II-like 1 (ACVRL1) genes are detected in around 90% of the patients; also 2% of patients harbor pathogenic variants at SMAD4 and GDF2. Importantly, the genetic cause of 8% of patients with clinical HHT remains unknown. Here, we present new putative genetic drivers of HHT. METHODS To identify new HHT genetic drivers, we performed exome sequencing of 19 HHT patients and relatives with unknown HHT genetic etiology. We applied a multistep filtration strategy to catalog deleterious variants and prioritize gene candidates based on their known relevance in endothelial cell biology. Additionally, we performed in vitro validation of one of the identified variants. RESULTS We identified variants in the INHA, HIF1A, JAK2, DNM2, POSTN, ANGPTL4, FOXO1 and SMAD6 genes as putative drivers in HHT. We have identified the SMAD6 p.(Glu407Lys) variant in one of the families; this is a loss-of-function variant leading to the activation of the BMP/TGFβ signaling in endothelial cells. CONCLUSIONS Variants in these genes should be considered for genetic testing in patients with HHT phenotype and negative for ACVRL1/ENG mutations.
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Affiliation(s)
- Pau Cerdà
- HHT Unit, Hospital Universitari de Bellvitge, L'Hospitalet de Llobregat, Spain; Internal Medicine Department, Hospital Universitari de Bellvitge, L'Hospitalet de Llobregat, Spain; Institut d'Investigació Biomèdica de Bellvitge (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Spain
| | - Sandra D Castillo
- Endothelial Pathobiology and Microenvironment Group, Josep Carreras Leukaemia Research Institute, Badalona, Spain
| | - Cinthia Aguilera
- HHT Unit, Hospital Universitari de Bellvitge, L'Hospitalet de Llobregat, Spain; Institut d'Investigació Biomèdica de Bellvitge (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Spain; Genetics Laboratory, Laboratori Clínic Territorial Metropolitana Sud, Hospital Universitari de Bellvitge, L'Hospitalet de Llobregat, Spain
| | - Adriana Iriarte
- HHT Unit, Hospital Universitari de Bellvitge, L'Hospitalet de Llobregat, Spain; Internal Medicine Department, Hospital Universitari de Bellvitge, L'Hospitalet de Llobregat, Spain; Institut d'Investigació Biomèdica de Bellvitge (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Spain
| | - José Luis Rocamora
- HHT Unit, Hospital Universitari de Bellvitge, L'Hospitalet de Llobregat, Spain; Molecular Signaling Group, Molecular Mechanisms and Experimental Therapy in Oncology Program (Oncobell), Institut d'Investigacio Biomedica de Bellvitge (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Spain
| | - Ane M Larrinaga
- Endothelial Pathobiology and Microenvironment Group, Josep Carreras Leukaemia Research Institute, Badalona, Spain
| | - Francesc Viñals
- Molecular Signaling Group, Molecular Mechanisms and Experimental Therapy in Oncology Program (Oncobell), Institut d'Investigacio Biomedica de Bellvitge (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Spain; Department of Physiological Sciences, Faculty of Medicine and Health Sciences, Universitat de Barcelona (UB), L'Hospitalet de Llobregat, Spain; Program Against Cancer Therapeutic Resistance (ProCURE), Institut Catala d'Oncologia (ICO), L'Hospitalet de Llobregat, Spain
| | - Mariona Graupera
- Endothelial Pathobiology and Microenvironment Group, Josep Carreras Leukaemia Research Institute, Badalona, Spain; CIBERONC, Instituto de Salud Carlos III, Madrid, Spain; ICREA, Institució Catalana de Recerca i Estudis Avançats, Barcelona, Spain
| | - Antoni Riera-Mestre
- HHT Unit, Hospital Universitari de Bellvitge, L'Hospitalet de Llobregat, Spain; Internal Medicine Department, Hospital Universitari de Bellvitge, L'Hospitalet de Llobregat, Spain; Institut d'Investigació Biomèdica de Bellvitge (IDIBELL), L'Hospitalet de Llobregat, Barcelona, Spain; Department of Clinical Sciences, Faculty of Medicine and Health Sciences, Universitat de Barcelona (UB), L'Hospitalet de Llobregat, Spain.
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Koff M, Monagas-Valentin P, Novikov B, Chandel I, Panin V. Protein O-mannosylation: one sugar, several pathways, many functions. Glycobiology 2023; 33:911-926. [PMID: 37565810 PMCID: PMC10859634 DOI: 10.1093/glycob/cwad067] [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: 07/16/2023] [Revised: 07/23/2023] [Accepted: 07/31/2023] [Indexed: 08/12/2023] Open
Abstract
Recent research has unveiled numerous important functions of protein glycosylation in development, homeostasis, and diseases. A type of glycosylation taking the center stage is protein O-mannosylation, a posttranslational modification conserved in a wide range of organisms, from yeast to humans. In animals, protein O-mannosylation plays a crucial role in the nervous system, whereas protein O-mannosylation defects cause severe neurological abnormalities and congenital muscular dystrophies. However, the molecular and cellular mechanisms underlying protein O-mannosylation functions and biosynthesis remain not well understood. This review outlines recent studies on protein O-mannosylation while focusing on the functions in the nervous system, summarizes the current knowledge about protein O-mannosylation biosynthesis, and discusses the pathologies associated with protein O-mannosylation defects. The evolutionary perspective revealed by studies in the Drosophila model system are also highlighted. Finally, the review touches upon important knowledge gaps in the field and discusses critical questions for future research on the molecular and cellular mechanisms associated with protein O-mannosylation functions.
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Affiliation(s)
- Melissa Koff
- Department of Biochemistry and Biophysics, AgriLife Research, Texas A&M University, College Station, College Station, TX 77843, United States
| | - Pedro Monagas-Valentin
- Department of Biochemistry and Biophysics, AgriLife Research, Texas A&M University, College Station, College Station, TX 77843, United States
| | - Boris Novikov
- Department of Biochemistry and Biophysics, AgriLife Research, Texas A&M University, College Station, College Station, TX 77843, United States
| | - Ishita Chandel
- Department of Biochemistry and Biophysics, AgriLife Research, Texas A&M University, College Station, College Station, TX 77843, United States
| | - Vladislav Panin
- Department of Biochemistry and Biophysics, AgriLife Research, Texas A&M University, College Station, College Station, TX 77843, United States
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5
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Yamaguchi M, Huynh MA, Chiyonobu T, Yoshida H. Knockdown of Chronophage in the nervous system mimics features of neurodevelopmental disorders caused by BCL11A/B variants. Exp Cell Res 2023; 433:113827. [PMID: 37926342 DOI: 10.1016/j.yexcr.2023.113827] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 10/18/2023] [Accepted: 10/19/2023] [Indexed: 11/07/2023]
Abstract
Neurodevelopmental disorders (NDD) are a group of disorders that include intellectual disability. Although several genes have been implicated in NDD, the molecular mechanisms underlying its pathogenesis remain unclear. Therefore, it is important to develop novel models to analyze the functions of NDD-causing genes in vivo. Recently, rare pathogenic variants of the B-cell lymphoma/leukemia11A/B (BCL11A/B) gene have been identified in several patients with NDD. Drosophila carries the Chronophage (Cph) gene, which has been predicted to be a homolog of BCL11A/B based on the conservation of the amino acid sequence. In the present study, we investigated whether nervous system-specific knockdown of Cph mimics NDD phenotypes in Drosophila. Nervous system-specific knockdown of Cph induced learning and locomotor defects in larvae and epilepsy-like behaviors in adults. The number of synaptic branches was also elevated in the larval neuromuscular junction without a corresponding increase in the number of boutons. Furthermore, the expression levels of putative target genes that are Drosophila homologs of the mammalian BCL11 target genes were decreased in Cph knockdown flies. These results suggest that Cph knockdown flies are a promising model for investigating the pathology of NDD-induced BCL11A/B dysfunction.
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Affiliation(s)
- Mizuki Yamaguchi
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan.
| | - Man Anh Huynh
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan
| | - Tomohiro Chiyonobu
- Department of Molecular Diagnostics and Therapeutics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-hirokoji, Kamigyo-ku, Kyoto, 602-8566, Japan
| | - Hideki Yoshida
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan; Advanced Insect Research Promotion Center, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan.
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6
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Rocha JJ, Jayaram SA, Stevens TJ, Muschalik N, Shah RD, Emran S, Robles C, Freeman M, Munro S. Functional unknomics: Systematic screening of conserved genes of unknown function. PLoS Biol 2023; 21:e3002222. [PMID: 37552676 PMCID: PMC10409296 DOI: 10.1371/journal.pbio.3002222] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 06/27/2023] [Indexed: 08/10/2023] Open
Abstract
The human genome encodes approximately 20,000 proteins, many still uncharacterised. It has become clear that scientific research tends to focus on well-studied proteins, leading to a concern that poorly understood genes are unjustifiably neglected. To address this, we have developed a publicly available and customisable "Unknome database" that ranks proteins based on how little is known about them. We applied RNA interference (RNAi) in Drosophila to 260 unknown genes that are conserved between flies and humans. Knockdown of some genes resulted in loss of viability, and functional screening of the rest revealed hits for fertility, development, locomotion, protein quality control, and resilience to stress. CRISPR/Cas9 gene disruption validated a component of Notch signalling and 2 genes contributing to male fertility. Our work illustrates the importance of poorly understood genes, provides a resource to accelerate future research, and highlights a need to support database curation to ensure that misannotation does not erode our awareness of our own ignorance.
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Affiliation(s)
- João J. Rocha
- MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | | | - Tim J. Stevens
- MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | | | - Rajen D. Shah
- Centre for Mathematical Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Sahar Emran
- MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Cristina Robles
- MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Matthew Freeman
- MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
- Sir William Dunn School of Pathology, University of Oxford, Oxford, United Kingdom
| | - Sean Munro
- MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
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7
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Larsen ISB, Povolo L, Zhou L, Tian W, Mygind KJ, Hintze J, Jiang C, Hartill V, Prescott K, Johnson CA, Mullegama SV, McConkie-Rosell A, McDonald M, Hansen L, Vakhrushev SY, Schjoldager KT, Clausen H, Worzfeld T, Joshi HJ, Halim A. The SHDRA syndrome-associated gene TMEM260 encodes a protein-specific O-mannosyltransferase. Proc Natl Acad Sci U S A 2023; 120:e2302584120. [PMID: 37186866 PMCID: PMC10214176 DOI: 10.1073/pnas.2302584120] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 04/21/2023] [Indexed: 05/17/2023] Open
Abstract
Mutations in the TMEM260 gene cause structural heart defects and renal anomalies syndrome, but the function of the encoded protein remains unknown. We previously reported wide occurrence of O-mannose glycans on extracellular immunoglobulin, plexin, transcription factor (IPT) domains found in the hepatocyte growth factor receptor (cMET), macrophage-stimulating protein receptor (RON), and plexin receptors, and further demonstrated that two known protein O-mannosylation systems orchestrated by the POMT1/2 and transmembrane and tetratricopeptide repeat-containing proteins 1-4 gene families were not required for glycosylation of these IPT domains. Here, we report that the TMEM260 gene encodes an ER-located protein O-mannosyltransferase that selectively glycosylates IPT domains. We demonstrate that disease-causing TMEM260 mutations impair O-mannosylation of IPT domains and that TMEM260 knockout in cells results in receptor maturation defects and abnormal growth of 3D cell models. Thus, our study identifies the third protein-specific O-mannosylation pathway in mammals and demonstrates that O-mannosylation of IPT domains serves critical functions during epithelial morphogenesis. Our findings add a new glycosylation pathway and gene to a growing group of congenital disorders of glycosylation.
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Affiliation(s)
- Ida Signe Bohse Larsen
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, University of Copenhagen, 2200Copenhagen N, Denmark
| | - Lorenzo Povolo
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, University of Copenhagen, 2200Copenhagen N, Denmark
| | - Luping Zhou
- Faculty of Medicine, Institute of Pharmacology, University of Marburg, 35043Marburg, Germany
| | - Weihua Tian
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, University of Copenhagen, 2200Copenhagen N, Denmark
| | - Kasper Johansen Mygind
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, University of Copenhagen, 2200Copenhagen N, Denmark
| | - John Hintze
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, University of Copenhagen, 2200Copenhagen N, Denmark
| | - Chen Jiang
- Faculty of Medicine, Institute of Pharmacology, University of Marburg, 35043Marburg, Germany
| | - Verity Hartill
- Leeds Institute of Medical Research, University of Leeds, St James’ University Hospital, LeedsLS2 9JT, United Kingdom
- Yorkshire Regional Genetics Service, Chapel Allerton Hospital, LeedsLS7 4SA, United Kingdom
| | - Katrina Prescott
- Yorkshire Regional Genetics Service, Chapel Allerton Hospital, LeedsLS7 4SA, United Kingdom
| | - Colin A. Johnson
- Leeds Institute of Medical Research, University of Leeds, St James’ University Hospital, LeedsLS2 9JT, United Kingdom
| | | | - Allyn McConkie-Rosell
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center, Durham, NC27710
| | - Marie McDonald
- Division of Medical Genetics, Department of Pediatrics, Duke University Medical Center, Durham, NC27710
| | - Lars Hansen
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, University of Copenhagen, 2200Copenhagen N, Denmark
| | - Sergey Y. Vakhrushev
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, University of Copenhagen, 2200Copenhagen N, Denmark
| | - Katrine T. Schjoldager
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, University of Copenhagen, 2200Copenhagen N, Denmark
| | - Henrik Clausen
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, University of Copenhagen, 2200Copenhagen N, Denmark
| | - Thomas Worzfeld
- Faculty of Medicine, Institute of Pharmacology, University of Marburg, 35043Marburg, Germany
- Max-Planck-Institute for Heart and Lung Research, 61231Bad Nauheim, Germany
| | - Hiren J. Joshi
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, University of Copenhagen, 2200Copenhagen N, Denmark
| | - Adnan Halim
- Copenhagen Center for Glycomics, Department of Cellular and Molecular Medicine, University of Copenhagen, 2200Copenhagen N, Denmark
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8
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Hu X, Guo B, Sun T, Wang W. Inhibition of glycolysis represses the growth and alleviates the endoplasmic reticulum stress of breast cancer cells by regulating TMTC3. Open Med (Wars) 2023; 18:20230635. [PMID: 37069941 PMCID: PMC10105522 DOI: 10.1515/med-2023-0635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 12/05/2022] [Accepted: 12/11/2022] [Indexed: 04/19/2023] Open
Abstract
Considering the role of glycolysis inhibition as a novel therapeutic strategy for cancer, including breast cancer (BC), we wondered whether glycolysis could affect BC progression by regulating transmembrane O-mannosyltransferase-targeting cadherins 3 (TMTC3). Following the intervention, lactic acid production in BC cells was monitored, and viability, proliferation, and apoptosis assays were performed. The expressions of TMTC3 and endoplasmic reticulum (ER) stress- and apoptosis-related factors Caspase-12, C/EBP homologous protein (CHOP), glucose-regulated protein 78 (GRP78), B-cell lymphoma-2 (Bcl-2), and Bcl-2 associated X (Bax) were quantified. TMTC3 was lowly expressed in BC tissue and cell. The promotion of glycolysis via glucose represses TMTC3 expression and apoptosis yet enhances lactic acid production and growth of BC cell, along with promoted levels of Caspase-12, CHOP, GRP78, and Bcl-2 yet repressed level of Bax, while the contrary results were evidenced after 2-deoxyglycouse intervention. Overexpressed TMTC3 additionally abrogated the effects of glycolysis on increasing the viability and proliferation yet inhibiting the apoptosis of BC cells, with the increased expressions of Caspase-12, CHOP, and GRP78, and Bcl-2 yet decreased level of Bax. Collectively, inhibiting glycolysis restrained the growth and attenuated the ER stress of BC cell by regulating TMTC3.
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Affiliation(s)
- Xue Hu
- Department of Breast Surgery, China-Japan Union Hospital of Jilin University, Changchun City, Jilin Province, 130033, China
| | - Baoliang Guo
- Department of General Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin City, Heilongjiang Province, China
| | - Tong Sun
- Department of Breast Surgery, China-Japan Union Hospital of Jilin University, Changchun City, Jilin Province, 130033, China
| | - Wan Wang
- Department of Breast Surgery, China-Japan Union Hospital of Jilin University, No. 126 Xiantai
Avenue, Nanguan District, Changchun City, Jilin Province, 130033, China
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A Drosophila model of the neurological symptoms in Mpv17-related diseases. Sci Rep 2022; 12:22632. [PMID: 36587049 PMCID: PMC9805426 DOI: 10.1038/s41598-022-27329-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Accepted: 12/30/2022] [Indexed: 01/01/2023] Open
Abstract
Mutations in the Mpv17 gene are responsible for MPV17-related hepatocerebral mitochondrial DNA depletion syndrome and Charcot-Marie-Tooth (CMT) disease. Although several models including mouse, zebrafish, and cultured human cells, have been developed, the models do not show any neurological defects, which are often observed in patients. Therefore, we knocked down CG11077 (Drosophila Mpv17; dMpv17), an ortholog of human MPV17, in the nervous system in Drosophila melanogaster and investigated the behavioral and cellular phenotypes. The resulting dMpv17 knockdown larvae showed impaired locomotor activity and learning ability consistent with mitochondrial defects suggested by the reductions in mitochondrial DNA and ATP production and the increases in the levels of lactate and reactive oxygen species. Furthermore, an abnormal morphology of the neuromuscular junction, at the presynaptic terminal, was observed in dMpv17 knockdown larvae. These results reproduce well the symptoms of human diseases and partially reproduce the phenotypes of Mpv17-deficient model organisms. Therefore, we suggest that neuron-specific dMpv17 knockdown in Drosophila is a useful model for investigation of MPV17-related hepatocerebral mitochondrial DNA depletion syndrome and CMT caused by Mpv17 dysfunction.
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10
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Lee JH. Invertebrate Model Organisms as a Platform to Investigate Rare Human Neurological Diseases. Exp Neurobiol 2022; 31:1-16. [PMID: 35256540 PMCID: PMC8907251 DOI: 10.5607/en22003] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 02/07/2022] [Accepted: 02/07/2022] [Indexed: 01/16/2023] Open
Abstract
Patients suffering from rare human diseases often go through a painful journey for finding a definite molecular diagnosis prerequisite of appropriate cures. With a novel variant isolated from a single patient, determination of its pathogenicity to end such "diagnostic odyssey" requires multi-step processes involving experts in diverse areas of interest, including clinicians, bioinformaticians and research scientists. Recent efforts in building large-scale genomic databases and in silico prediction platforms have facilitated identification of potentially pathogenic variants causative of rare human diseases of a Mendelian basis. However, the functional significance of individual variants remains elusive in many cases, thus requiring incorporation of versatile and rapid model organism (MO)-based platforms for functional analyses. In this review, the current scope of rare disease research is briefly discussed. In addition, an overview of invertebrate MOs for their key features relevant to rare neurological diseases is provided, with the characteristics of two representative invertebrate MOs, Drosophila melanogaster and Caenorhabditis elegans, as well as the challenges against them. Finally, recently developed research networks integrating these MOs in collaborative research are portraited with an array of bioinformatical analyses embedded. A comprehensive survey of MO-based research activities provided in this review will help us to design a wellstructured analysis of candidate genes or potentially pathogenic variants for their roles in rare neurological diseases in future.
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Affiliation(s)
- Ji-Hye Lee
- Department of Oral Pathology & Life Science in Dentistry, School of Dentistry, Pusan National University, Yangsan 50612, Korea.,Dental Life Science Institute, Pusan National University, Yangsan 50612, Korea.,Periodontal Disease Signaling Network Research Center, Pusan National University, Yangsan 50612, Korea
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11
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Ecovoiu AA, Ratiu AC, Micheu MM, Chifiriuc MC. Inter-Species Rescue of Mutant Phenotype-The Standard for Genetic Analysis of Human Genetic Disorders in Drosophila melanogaster Model. Int J Mol Sci 2022; 23:2613. [PMID: 35269756 PMCID: PMC8909942 DOI: 10.3390/ijms23052613] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 02/23/2022] [Accepted: 02/24/2022] [Indexed: 11/16/2022] Open
Abstract
Drosophila melanogaster (the fruit fly) is arguably a superstar of genetics, an astonishing versatile experimental model which fueled no less than six Nobel prizes in medicine. Nowadays, an evolving research endeavor is to simulate and investigate human genetic diseases in the powerful D. melanogaster platform. Such a translational experimental strategy is expected to allow scientists not only to understand the molecular mechanisms of the respective disorders but also to alleviate or even cure them. In this regard, functional gene orthology should be initially confirmed in vivo by transferring human or vertebrate orthologous transgenes in specific mutant backgrounds of D. melanogaster. If such a transgene rescues, at least partially, the mutant phenotype, then it qualifies as a strong candidate for modeling the respective genetic disorder in the fruit fly. Herein, we review various examples of inter-species rescue of relevant mutant phenotypes of the fruit fly and discuss how these results recommend several human genes as candidates to study and validate genetic variants associated with human diseases. We also consider that a wider implementation of this evolutionist exploratory approach as a standard for the medicine of genetic disorders would allow this particular field of human health to advance at a faster pace.
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Affiliation(s)
- Alexandru Al. Ecovoiu
- Department of Genetics, Faculty of Biology, University of Bucharest, 060101 Bucharest, Romania;
| | - Attila Cristian Ratiu
- Department of Genetics, Faculty of Biology, University of Bucharest, 060101 Bucharest, Romania;
| | - Miruna Mihaela Micheu
- Department of Cardiology, Clinical Emergency Hospital of Bucharest, 014461 Bucharest, Romania;
| | - Mariana Carmen Chifiriuc
- The Research Institute of the University of Bucharest and Faculty of Biology, University of Bucharest, 050095 Bucharest, Romania;
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12
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Hang J, Wang J, Lu M, Xue Y, Qiao J, Tao L. Protein O-mannosylation across kingdoms and related diseases: From glycobiology to glycopathology. Biomed Pharmacother 2022; 148:112685. [PMID: 35149389 DOI: 10.1016/j.biopha.2022.112685] [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: 12/06/2021] [Revised: 01/29/2022] [Accepted: 02/01/2022] [Indexed: 11/18/2022] Open
Abstract
The post-translational glycosylation of proteins by O-linked α-mannose is conserved from bacteria to humans. Due to advances in high-throughput mass spectrometry-based approaches, a variety of glycoproteins are identified to be O-mannosylated. Various proteins with O-mannosylation are involved in biological processes, providing essential necessity for proper growth and development. In this review, we summarize the process and regulation of O-mannosylation. The multi-step O-mannosylation procedures are quite dynamic and complex, especially when considering the structural and functional inspection of the involved enzymes. The widely studied O-mannosylated proteins in human include α-Dystroglycan (α-DG), cadherins, protocadherins, and plexin, and their aberrant O-mannosylation are associated with many diseases. In addition, O-mannosylation also contributes to diverse functions in lower eukaryotes and prokaryotes. Finally, we present the relationship between O-mannosylation and gut microbiota (GM), and elucidate that O-mannosylation in microbiome is of great importance in the dynamic balance of GM. Our study provides an overview of the processes of O-mannosylation in mammalian cells and other organisms, and also associated regulated enzymes and biological functions, which could contribute to the understanding of newly discovered O-mannosylated glycoproteins.
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Affiliation(s)
- Jing Hang
- Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing 100191, China; National Clinical Research Center for Obstetrics and Gynecology (Peking University Third Hospital), Beijing 100191, China; Key Laboratory of Assisted Reproduction (Peking University), Ministry of Education, Beijing 100191, China; Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology, Beijing 100191, China
| | - Jinpeng Wang
- Department of Orthopedics, First Hospital of China Medical University, Shenyang 110001, China
| | - Minzhen Lu
- Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing 100191, China; National Clinical Research Center for Obstetrics and Gynecology (Peking University Third Hospital), Beijing 100191, China; Key Laboratory of Assisted Reproduction (Peking University), Ministry of Education, Beijing 100191, China; Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology, Beijing 100191, China
| | - Yuchuan Xue
- The First Department of Clinical Medicine, China Medical University, Shenyang 110001, China
| | - Jie Qiao
- Center for Reproductive Medicine, Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing 100191, China; National Clinical Research Center for Obstetrics and Gynecology (Peking University Third Hospital), Beijing 100191, China; Key Laboratory of Assisted Reproduction (Peking University), Ministry of Education, Beijing 100191, China; Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproductive Technology, Beijing 100191, China.
| | - Lin Tao
- Department of Orthopedics, First Hospital of China Medical University, Shenyang 110001, China.
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13
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Vriend I, Oegema R. Genetic causes underlying grey matter heterotopia. Eur J Paediatr Neurol 2021; 35:82-92. [PMID: 34666232 DOI: 10.1016/j.ejpn.2021.09.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 09/21/2021] [Indexed: 11/15/2022]
Abstract
Grey matter heterotopia (GMH) can cause of seizures and are associated with a wide range of neurodevelopmental disorders and syndromes. They are caused by a failure of neuronal migration during fetal development, leading to clusters of neurons that have not reached their final destination in the cerebral cortex. We have performed an extensive literature search in Pubmed, OMIM, and Google scholar and provide an overview of known genetic associations with periventricular nodular heterotopia (PNVH), subcortical band heterotopia (SBH) and other subcortical heterotopia (SUBH). We classified the heterotopias as PVNH, SBH, SUBH or other and collected the genetic information, frequency, imaging features and salient features in tables for every subtype of heterotopia. This resulted in 105 PVNH, 16 SBH and 25 SUBH gene/locus associations, making a total of 146 genes and chromosomal loci. Our study emphasizes the extreme genetic heterogeneity underlying GMH. It will aid the clinician in establishing an differential diagnosis and eventually a molecular diagnosis in GMH patients. A diagnosis enables proper counseling of prognosis and recurrence risks, and enables individualized patient management.
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Affiliation(s)
- Ilona Vriend
- Department of Genetics, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
| | - Renske Oegema
- Department of Genetics, University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands.
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14
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Lu YT, Hsu CY, Liu YT, Chan CK, Chuang YC, Lin CH, Chang KP, Ho CJ, Ng CC, Lim KS, Tsai MH. The clinical and imaging features of FLNA positive and negative periventricular nodular heterotopia. Biomed J 2021; 45:542-548. [PMID: 35660364 PMCID: PMC9421925 DOI: 10.1016/j.bj.2021.05.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Revised: 04/10/2021] [Accepted: 05/13/2021] [Indexed: 11/30/2022] Open
Affiliation(s)
- Yan-Ting Lu
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Chung-Yao Hsu
- Department of Neurology, Kaohsiung Medical University Hospital, Kaohsiung, Taiwan
| | - Yo-Tsen Liu
- Division of Epilepsy, Department of Neurology Neurological Institute, Taipei Veterans General Hospital, Taipei, Taiwan; Department of Neurology, National Yang-Ming University School of Medicine, Taipei, Taiwan; Institute of Brain Science, National Yang-Ming University, Taipei, Taiwan; Brain Research Center, National Yang-Ming University, Taipei, Taiwan
| | - Chung-Kin Chan
- Genetics and Molecular Biology, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
| | - Yao-Chung Chuang
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Chih-Hsiang Lin
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Kai-Ping Chang
- Department of Pediatric, Wei-Gong Memorial Hospital, Miaoli, Taiwan; Department of Pediatric, National Yang-Ming University School of Medicine, Taipei, Taiwan
| | - Chen-Jui Ho
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Ching-Ching Ng
- Genetics and Molecular Biology, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia
| | - Kheng-Seang Lim
- Division of Neurology, Department of Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Meng-Han Tsai
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan; College of Medicine, Chang Gung University, Taoyuan, Taiwan.
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15
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Eisenhaber B, Sinha S, Jadalanki CK, Shitov VA, Tan QW, Sirota FL, Eisenhaber F. Conserved sequence motifs in human TMTC1, TMTC2, TMTC3, and TMTC4, new O-mannosyltransferases from the GT-C/PMT clan, are rationalized as ligand binding sites. Biol Direct 2021; 16:4. [PMID: 33436046 PMCID: PMC7801869 DOI: 10.1186/s13062-021-00291-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Accepted: 01/04/2021] [Indexed: 12/05/2022] Open
Abstract
BACKGROUND The human proteins TMTC1, TMTC2, TMTC3 and TMTC4 have been experimentally shown to be components of a new O-mannosylation pathway. Their own mannosyl-transferase activity has been suspected but their actual enzymatic potential has not been demonstrated yet. So far, sequence analysis of TMTCs has been compromised by evolutionary sequence divergence within their membrane-embedded N-terminal region, sequence inaccuracies in the protein databases and the difficulty to interpret the large functional variety of known homologous proteins (mostly sugar transferases and some with known 3D structure). RESULTS Evolutionary conserved molecular function among TMTCs is only possible with conserved membrane topology within their membrane-embedded N-terminal regions leading to the placement of homologous long intermittent loops at the same membrane side. Using this criterion, we demonstrate that all TMTCs have 11 transmembrane regions. The sequence segment homologous to Pfam model DUF1736 is actually just a loop between TM7 and TM8 that is located in the ER lumen and that contains a small hydrophobic, but not membrane-embedded helix. Not only do the membrane-embedded N-terminal regions of TMTCs share a common fold and 3D structural similarity with subgroups of GT-C sugar transferases. The conservation of residues critical for catalysis, for binding of a divalent metal ion and of the phosphate group of a lipid-linked sugar moiety throughout enzymatically and structurally well-studied GT-Cs and sequences of TMTCs indicates that TMTCs are actually sugar-transferring enzymes. We present credible 3D structural models of all four TMTCs (derived from their closest known homologues 5ezm/5f15) and find observed conserved sequence motifs rationalized as binding sites for a metal ion and for a dolichyl-phosphate-mannose moiety. CONCLUSIONS With the results from both careful sequence analysis and structural modelling, we can conclusively say that the TMTCs are enzymatically active sugar transferases belonging to the GT-C/PMT superfamily. The DUF1736 segment, the loop between TM7 and TM8, is critical for catalysis and lipid-linked sugar moiety binding. Together with the available indirect experimental data, we conclude that the TMTCs are not only part of an O-mannosylation pathway in the endoplasmic reticulum of upper eukaryotes but, actually, they are the sought mannosyl-transferases.
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Affiliation(s)
- Birgit Eisenhaber
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Republic of Singapore.
- Genome Institute of Singapore (BII), Agency for Science, Technology and Research (A*STAR), 60 Biopolis Street, Singapore, 138672, Republic of Singapore.
| | - Swati Sinha
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Republic of Singapore
| | - Chaitanya K Jadalanki
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Republic of Singapore
| | - Vladimir A Shitov
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Republic of Singapore
- Siberian State Medical University, Moskovskiy Trakt, 2, Tomsk, Tomsk Oblast, 634050, Russia
| | - Qiao Wen Tan
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Republic of Singapore
- School of Biological Science (SBS), Nanyang Technological University (NTU), 60 Nanyang Drive, Singapore, 637551, Republic of Singapore
| | - Fernanda L Sirota
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Republic of Singapore
| | - Frank Eisenhaber
- Bioinformatics Institute (BII), Agency for Science, Technology and Research (A*STAR), 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Republic of Singapore.
- Genome Institute of Singapore (BII), Agency for Science, Technology and Research (A*STAR), 60 Biopolis Street, Singapore, 138672, Republic of Singapore.
- School of Biological Science (SBS), Nanyang Technological University (NTU), 60 Nanyang Drive, Singapore, 637551, Republic of Singapore.
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16
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Mealer RG, Williams SE, Daly MJ, Scolnick EM, Cummings RD, Smoller JW. Glycobiology and schizophrenia: a biological hypothesis emerging from genomic research. Mol Psychiatry 2020; 25:3129-3139. [PMID: 32377000 PMCID: PMC8081046 DOI: 10.1038/s41380-020-0753-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 04/09/2020] [Accepted: 04/22/2020] [Indexed: 12/12/2022]
Abstract
Advances in genomics are opening new windows into the biology of schizophrenia. Though common variants individually have small effects on disease risk, GWAS provide a powerful opportunity to explore pathways and mechanisms contributing to pathophysiology. Here, we highlight an underappreciated biological theme emerging from GWAS: the role of glycosylation in schizophrenia. The strongest coding variant in schizophrenia GWAS is a missense mutation in the manganese transporter SLC39A8, which is associated with altered glycosylation patterns in humans. Furthermore, variants near several genes encoding glycosylation enzymes are unambiguously associated with schizophrenia: FUT9, MAN2A1, TMTC1, GALNT10, and B3GAT1. Here, we summarize the known biological functions, target substrates, and expression patterns of these enzymes as a primer for future studies. We also highlight a subset of schizophrenia-associated proteins critically modified by glycosylation including glutamate receptors, voltage-gated calcium channels, the dopamine D2 receptor, and complement glycoproteins. We hypothesize that common genetic variants alter brain glycosylation and play a fundamental role in the development of schizophrenia. Leveraging these findings will advance our mechanistic understanding of disease and may provide novel avenues for treatment development.
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Affiliation(s)
- Robert G. Mealer
- Massachusetts General Hospital, Department of Psychiatry.,The Stanley Center for Psychiatric Research at Broad Institute.,Department of Surgery, Beth Israel Deaconess Medical Center. Harvard Medical School, Boston MA.,Corresponding Author: Robert Gene Mealer, M.D., Ph.D., Richard B. Simches Research Center, 185 Cambridge St, 6th Floor, Boston, MA 02114, Tel: +1 (617) 724-9076,
| | - Sarah E. Williams
- Massachusetts General Hospital, Department of Psychiatry.,Department of Surgery, Beth Israel Deaconess Medical Center. Harvard Medical School, Boston MA
| | - Mark J. Daly
- Massachusetts General Hospital, Department of Psychiatry.,The Stanley Center for Psychiatric Research at Broad Institute
| | - Edward M. Scolnick
- Massachusetts General Hospital, Department of Psychiatry.,The Stanley Center for Psychiatric Research at Broad Institute
| | - Richard D. Cummings
- Department of Surgery, Beth Israel Deaconess Medical Center. Harvard Medical School, Boston MA
| | - Jordan W. Smoller
- Massachusetts General Hospital, Department of Psychiatry.,The Stanley Center for Psychiatric Research at Broad Institute
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17
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A Report on a Family with TMTC3-Related Syndrome and Review. Case Rep Med 2020; 2020:7163038. [PMID: 33293961 PMCID: PMC7714604 DOI: 10.1155/2020/7163038] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 10/12/2020] [Accepted: 10/22/2020] [Indexed: 11/17/2022] Open
Abstract
Recessive mutations in the TMTC3 gene have been reported in thirteen patients to date exhibiting development delay, intellectual disability (ID), seizures, and muscular hypotonia, accompanied occasionally by neuronal migration defects expressed as either cobblestone lissencephaly or periventricular hypertopia. Here, we report a new case of a TMTC3-related syndrome in a Lebanese family with two affected siblings showing severe psychomotor retardation, intellectual disability, microcephaly, absence of speech, muscular hypotonia, and seizures. Whole exome sequencing revealed a homozygous pathogenic variant c.211 C > T (p.R71C) in the TMTC3 gene in both siblings. A review of the literature on TMTC3-related syndrome and its causal mutations is provided.
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18
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Takai A, Chiyonobu T, Ueoka I, Tanaka R, Tozawa T, Yoshida H, Morimoto M, Hosoi H, Yamaguchi M. A novel Drosophila model for neurodevelopmental disorders associated with Shwachman-Diamond syndrome. Neurosci Lett 2020; 739:135449. [PMID: 33115644 DOI: 10.1016/j.neulet.2020.135449] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 09/19/2020] [Accepted: 10/08/2020] [Indexed: 10/23/2022]
Abstract
Genetic defects in ribosome biogenesis result in a group of diseases called ribosomopathies. Patients with ribosomopathies manifest multiorgan phenotypes, including neurological impairments. A well-characterized ribosomopathy, Shwachman-Diamond syndrome (SDS), is mainly associated with loss-of-function mutations in the causal gene SBDS. Children with SDS have neurodevelopmental disorders; however, the neurological consequences of SBDS dysfunction remain poorly defined. In the present study, we investigated the phenotype of Drosophila melanogaster following knockdown of CG8549, the Drosophila ortholog of human SBDS, to provide evidence for the neurological consequences of reduction in physiological SBDS functions. The pan-neuron-specific knockdown of CG8549 was associated with locomotive disabilities, mechanically induced seizures, hyperactivity, learning impairments, and anatomical defects in presynaptic terminals. These results provide the first evidence of a direct link between a reduction in physiological SBDS function and neurological impairments.
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Affiliation(s)
- Akari Takai
- Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan
| | - Tomohiro Chiyonobu
- Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.
| | - Ibuki Ueoka
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan
| | - Ryo Tanaka
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan
| | - Takenori Tozawa
- Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan
| | - Hideki Yoshida
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan.
| | - Masafumi Morimoto
- Department of Medical Science, School of Nursing, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-hirokoji, Kamigyo-ku, Kyoto, 602-8566, Japan
| | - Hajime Hosoi
- Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan
| | - Masamitsu Yamaguchi
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan
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19
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Ferent J, Zaidi D, Francis F. Extracellular Control of Radial Glia Proliferation and Scaffolding During Cortical Development and Pathology. Front Cell Dev Biol 2020; 8:578341. [PMID: 33178693 PMCID: PMC7596222 DOI: 10.3389/fcell.2020.578341] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 09/08/2020] [Indexed: 01/14/2023] Open
Abstract
During the development of the cortex, newly generated neurons migrate long-distances in the expanding tissue to reach their final positions. Pyramidal neurons are produced from dorsal progenitors, e.g., radial glia (RGs) in the ventricular zone, and then migrate along RG processes basally toward the cortex. These neurons are hence dependent upon RG extensions to support their migration from apical to basal regions. Several studies have investigated how intracellular determinants are required for RG polarity and subsequent formation and maintenance of their processes. Fewer studies have identified the influence of the extracellular environment on this architecture. This review will focus on extracellular factors which influence RG morphology and pyramidal neuronal migration during normal development and their perturbations in pathology. During cortical development, RGs are present in different strategic positions: apical RGs (aRGs) have their cell bodies located in the ventricular zone with an apical process contacting the ventricle, while they also have a basal process extending radially to reach the pial surface of the cortex. This particular conformation allows aRGs to be exposed to long range and short range signaling cues, whereas basal RGs (bRGs, also known as outer RGs, oRGs) have their cell bodies located throughout the cortical wall, limiting their access to ventricular factors. Long range signals impacting aRGs include secreted molecules present in the embryonic cerebrospinal fluid (e.g., Neuregulin, EGF, FGF, Wnt, BMP). Secreted molecules also contribute to the extracellular matrix (fibronectin, laminin, reelin). Classical short range factors include cell to cell signaling, adhesion molecules and mechano-transduction mechanisms (e.g., TAG1, Notch, cadherins, mechanical tension). Changes in one or several of these components influencing the RG extracellular environment can disrupt the development or maintenance of RG architecture on which neuronal migration relies, leading to a range of cortical malformations. First, we will detail the known long range signaling cues impacting RG. Then, we will review how short range cell contacts are also important to instruct the RG framework. Understanding how RG processes are structured by their environment to maintain and support radial migration is a critical part of the investigation of neurodevelopmental disorders.
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Affiliation(s)
- Julien Ferent
- Inserm, U 1270, Paris, France.,Sorbonne University, UMR-S 1270, IFM, Paris, France.,Institut du Fer á Moulin, Paris, France
| | - Donia Zaidi
- Inserm, U 1270, Paris, France.,Sorbonne University, UMR-S 1270, IFM, Paris, France.,Institut du Fer á Moulin, Paris, France
| | - Fiona Francis
- Inserm, U 1270, Paris, France.,Sorbonne University, UMR-S 1270, IFM, Paris, France.,Institut du Fer á Moulin, Paris, France
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20
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Liu G, Zhou Q, Lin H, Li N, Ye H, Wang J. Novel compound variants of the TMTC3 gene cause cobblestone lissencephaly-like syndrome: A case report. Exp Ther Med 2020; 20:97. [PMID: 32973946 PMCID: PMC7507045 DOI: 10.3892/etm.2020.9226] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Accepted: 08/07/2020] [Indexed: 11/06/2022] Open
Abstract
Biallelic variants in the transmembrane O-mannosyltransferase targeting cadherins 3 (TMTC3) gene have been reported to cause two distinct types of neuron migration defect diseases, known as cobblestone lissencephaly (COB) and periventricular nodular heterotopia (PVNH), combined with intellectual disability and nocturnal seizures. The aim of the current study was to identify the genetic cause of a 22-month-old Chinese boy who presented with white matter plaques, a small frontal lobe, myelin dysplasia, microcephaly, psychomotor delay, language development delay, truncal hypotonia, intractable epilepsy, infantile spasm and bilateral single transverse palmar creases. Whole-exome sequencing revealed novel heterozygous variant compounds in the TMTC3 gene (c.1123G>A, p.Glu375Lys and c.1126_1129del, p.Arg376Tyrfs*13). Most of the clinical features of the patient are consistent with COB. However, the deformities in the brain (white matter plaques, small frontal lobe and myelin dysplasia) in the patient were more severe compared with those generally exhibited by PVNH, but less severe compared with those presented by COB. Moreover, the patient exhibited bilateral single transverse palmar creases, which, to the best of our knowledge, have not been described previously in patients with a TMTC3 variation. In summary, the current study reported a pediatric Chinese patient with COB-like syndrome caused by TMTC3 gene variations. The present results indicated that variation in the TMTC3 gene can lead to highly variable clinical phenotypes.
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Affiliation(s)
- Guanghua Liu
- Department of Pediatric Internal Medicine, Fujian Maternity and Child Health Hospital, Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350001, P.R. China
| | - Qing Zhou
- Department of Pediatric Internal Medicine, Fujian Maternity and Child Health Hospital, Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350001, P.R. China
| | - Han Lin
- Department of Pediatric Internal Medicine, Fujian Maternity and Child Health Hospital, Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350001, P.R. China
| | - Niu Li
- Department of Medical Genetics and Molecular Diagnostic Laboratory, Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai 200127, P.R. China
| | - Hong Ye
- Department of Pediatric Internal Medicine, Fujian Maternity and Child Health Hospital, Affiliated Hospital of Fujian Medical University, Fuzhou, Fujian 350001, P.R. China
| | - Jian Wang
- Department of Medical Genetics and Molecular Diagnostic Laboratory, Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai 200127, P.R. China
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21
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Takai A, Yamaguchi M, Yoshida H, Chiyonobu T. Investigating Developmental and Epileptic Encephalopathy Using Drosophila melanogaster. Int J Mol Sci 2020; 21:ijms21176442. [PMID: 32899411 PMCID: PMC7503973 DOI: 10.3390/ijms21176442] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Revised: 08/30/2020] [Accepted: 09/01/2020] [Indexed: 12/16/2022] Open
Abstract
Developmental and epileptic encephalopathies (DEEs) are the spectrum of severe epilepsies characterized by early-onset, refractory seizures occurring in the context of developmental regression or plateauing. Early infantile epileptic encephalopathy (EIEE) is one of the earliest forms of DEE, manifesting as frequent epileptic spasms and characteristic electroencephalogram findings in early infancy. In recent years, next-generation sequencing approaches have identified a number of monogenic determinants underlying DEE. In the case of EIEE, 85 genes have been registered in Online Mendelian Inheritance in Man as causative genes. Model organisms are indispensable tools for understanding the in vivo roles of the newly identified causative genes. In this review, we first present an overview of epilepsy and its genetic etiology, especially focusing on EIEE and then briefly summarize epilepsy research using animal and patient-derived induced pluripotent stem cell (iPSC) models. The Drosophila model, which is characterized by easy gene manipulation, a short generation time, low cost and fewer ethical restrictions when designing experiments, is optimal for understanding the genetics of DEE. We therefore highlight studies with Drosophila models for EIEE and discuss the future development of their practical use.
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Affiliation(s)
- Akari Takai
- Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan;
| | - Masamitsu Yamaguchi
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 603-8585, Japan; (M.Y.); (H.Y.)
- Kansai Gakken Laboratory, Kankyo Eisei Yakuhin Co. Ltd., Kyoto 619-0237, Japan
| | - Hideki Yoshida
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 603-8585, Japan; (M.Y.); (H.Y.)
| | - Tomohiro Chiyonobu
- Department of Pediatrics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kyoto 602-8566, Japan;
- Correspondence:
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22
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Hegele RA, Dron JS. 2019 George Lyman Duff Memorial Lecture: Three Decades of Examining DNA in Patients With Dyslipidemia. Arterioscler Thromb Vasc Biol 2020; 40:1970-1981. [PMID: 32762461 DOI: 10.1161/atvbaha.120.313065] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Dyslipidemias include both rare single gene disorders and common conditions that have a complex underlying basis. In London, ON, there is fortuitous close physical proximity between the Lipid Genetics Clinic and the London Regional Genomics Centre. For >30 years, we have applied DNA sequencing of clinical samples to help answer scientific questions. More than 2000 patients referred with dyslipidemias have participated in an ongoing translational research program. In 2013, we transitioned to next-generation sequencing; our targeted panel is designed to concurrently assess both monogenic and polygenic contributions to dyslipidemias. Patient DNA is screened for rare variants underlying 25 mendelian dyslipidemias, including familial hypercholesterolemia, hepatic lipase deficiency, abetalipoproteinemia, and familial chylomicronemia syndrome. Furthermore, polygenic scores for LDL (low-density lipoprotein) and HDL (high-density lipoprotein) cholesterol, and triglycerides are calculated for each patient. We thus simultaneously document both rare and common genetic variants, allowing for a broad view of genetic predisposition for both individual patients and cohorts. For instance, among patients referred with severe hypertriglyceridemia, defined as ≥10 mmol/L (≥885 mg/dL), <1% have a mendelian disorder (ie, autosomal recessive familial chylomicronemia syndrome), ≈15% have heterozygous rare variants (a >3-fold increase over normolipidemic individuals), and ≈35% have an extreme polygenic score (a >3-fold increase over normolipidemic individuals). Other dyslipidemias show a different mix of genetic determinants. Genetic results are discussed with patients and can support clinical decision-making. Integrating DNA testing into clinical care allows for a bidirectional flow of information, which facilitates scientific discoveries and clinical translation.
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Affiliation(s)
- Robert A Hegele
- From the Department of Medicine (R.A.H.), Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
- Department of Biochemistry (R.A.H., J.S.D.), Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
- Robarts Research Institute (R.A.H., J.S.D.), Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
| | - Jacqueline S Dron
- Department of Biochemistry (R.A.H., J.S.D.), Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
- Robarts Research Institute (R.A.H., J.S.D.), Schulich School of Medicine and Dentistry, Western University, London, ON, Canada
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23
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Boycott KM, Campeau PM, Howley HE, Pavlidis P, Rogic S, Oriel C, Berman JN, Hamilton RM, Hicks GG, Lipshitz HD, Masson JY, Shoubridge EA, Junker A, Leroux MR, McMaster CR, Michaud JL, Turvey SE, Dyment D, Innes AM, van Karnebeek CD, Lehman A, Cohn RD, MacDonald IM, Rachubinski RA, Frosk P, Vandersteen A, Wozniak RW, Pena IA, Wen XY, Lacaze-Masmonteil T, Rankin C, Hieter P. The Canadian Rare Diseases Models and Mechanisms (RDMM) Network: Connecting Understudied Genes to Model Organisms. Am J Hum Genet 2020; 106:143-152. [PMID: 32032513 DOI: 10.1016/j.ajhg.2020.01.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 01/10/2020] [Indexed: 01/14/2023] Open
Abstract
Advances in genomics have transformed our ability to identify the genetic causes of rare diseases (RDs), yet we have a limited understanding of the mechanistic roles of most genes in health and disease. When a novel RD gene is first discovered, there is minimal insight into its biological function, the pathogenic mechanisms of disease-causing variants, and how therapy might be approached. To address this gap, the Canadian Rare Diseases Models and Mechanisms (RDMM) Network was established to connect clinicians discovering new disease genes with Canadian scientists able to study equivalent genes and pathways in model organisms (MOs). The Network is built around a registry of more than 500 Canadian MO scientists, representing expertise for over 7,500 human genes. RDMM uses a committee process to identify and evaluate clinician-MO scientist collaborations and approve 25,000 Canadian dollars in catalyst funding. To date, we have made 85 clinician-MO scientist connections and funded 105 projects. These collaborations help confirm variant pathogenicity and unravel the molecular mechanisms of RD, and also test novel therapies and lead to long-term collaborations. To expand the impact and reach of this model, we made the RDMM Registry open-source, portable, and customizable, and we freely share our committee structures and processes. We are currently working with emerging networks in Europe, Australia, and Japan to link international RDMM networks and registries and enable matches across borders. We will continue to create meaningful collaborations, generate knowledge, and advance RD research locally and globally for the benefit of patients and families living with RD.
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Affiliation(s)
- Kym M Boycott
- CHEO Research Institute, University of Ottawa, Ottawa, ON K1H 8L1, Canada.
| | - Philippe M Campeau
- Centre de Recherche du CHU Ste-Justine, Department of Pediatrics, Université de Montréal, Montréal, QC H3T 1C5, Canada
| | - Heather E Howley
- CHEO Research Institute, University of Ottawa, Ottawa, ON K1H 8L1, Canada
| | - Paul Pavlidis
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; Department of Psychiatry, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Sanja Rogic
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada; Department of Psychiatry, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Christine Oriel
- Maternal Infant Child and Youth Research Network (MICYRN), Vancouver, BC V5Z 4H4, Canada
| | - Jason N Berman
- CHEO Research Institute, University of Ottawa, Ottawa, ON K1H 8L1, Canada
| | - Robert M Hamilton
- Labatt Family Heart Centre and Translational Medicine, Hospital for Sick Children, Toronto, ON M5G 1X8, Canada
| | - Geoffrey G Hicks
- Regenerative Medicine Program, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB R3E 3P5, Canada; Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB R3E 3P5, Canada
| | - Howard D Lipshitz
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Jean-Yves Masson
- Oncology Division, CHU de Québec-Université Laval, Laval University Cancer Research Center, Quebec City, QC, G1R 3S3, Canada
| | - Eric A Shoubridge
- Department of Human Genetics, Montreal Neurological Institute, McGill University, Montreal, QC H3A 2B4, Canada
| | - Anne Junker
- Department of Pediatrics, British Columbia Children's Hospital Research Institute, University of British Columbia, Vancouver, BC V6H 3N1, Canada
| | - Michel R Leroux
- Department of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC V5A 1S6, Canada
| | | | - Jaques L Michaud
- Centre de Recherche du CHU Ste-Justine, Department of Pediatrics, Université de Montréal, Montréal, QC H3T 1C5, Canada
| | - Stuart E Turvey
- Department of Human Genetics, Montreal Neurological Institute, McGill University, Montreal, QC H3A 2B4, Canada
| | - David Dyment
- CHEO Research Institute, University of Ottawa, Ottawa, ON K1H 8L1, Canada
| | - A Micheil Innes
- Department of Medical Genetics, Cumming School of Medicine, University of Calgary, Alberta Children's Hospital, Calgary, AB T2N 4N1, Canada
| | - Clara D van Karnebeek
- Department of Human Genetics, Montreal Neurological Institute, McGill University, Montreal, QC H3A 2B4, Canada; Department of Pediatrics, Amsterdam University Medical Centres, Amsterdam, the Netherlands; Department of Clinical Genetics, Amsterdam University Medical Centres, Amsterdam, the Netherlands
| | - Anna Lehman
- Department of Medical Genetics, University of British Columbia, Vancouver, BC V6H 3N1, Canada
| | - Ronald D Cohn
- Genetics and Genome Biology Program, SickKids Research Institute, Department of Paediatrics and Molecular Genetics, University of Toronto, Toronto, ON M5G 0A4, Canada
| | - Ian M MacDonald
- Department of Ophthalmology and Visual Sciences, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2R7, Canada
| | - Richard A Rachubinski
- Genetics and Genome Biology Program, SickKids Research Institute, Department of Paediatrics and Molecular Genetics, University of Toronto, Toronto, ON M5G 0A4, Canada
| | - Patrick Frosk
- Department of Pediatrics and Child Health, University of Manitoba, Winnipeg, MB R3A 1S1, Canada
| | - Anthony Vandersteen
- Department of Pediatrics, Maritime Medical Genetics Service, Dalhousie University, IWK Health Centre, Halifax, NS B3K 6R8, Canada
| | - Richard W Wozniak
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Izabella A Pena
- CHEO Research Institute, University of Ottawa, Ottawa, ON K1H 8L1, Canada
| | - Xiao-Yan Wen
- Zebrafish Centre for Advanced Drug Discovery, Keenan Research Centre for Biomedical Science, St Michael's Hospital, Unity Health Toronto, Department of Medicine, University of Toronto, Toronto, ON M5B 1T8
| | - Thierry Lacaze-Masmonteil
- Maternal Infant Child and Youth Research Network (MICYRN), Vancouver, BC V5Z 4H4, Canada; Department of Pediatrics, Cumming School of Medicine, University of Calgary, Calgary, AB T2N 4N1, Canada
| | - Catharine Rankin
- Department of Psychology, University of British Columbia, Vancouver, BC V6T 1Z4, Canada
| | - Philip Hieter
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
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24
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Graham JB, Sunryd JC, Mathavan K, Weir E, Larsen ISB, Halim A, Clausen H, Cousin H, Alfandari D, Hebert DN. Endoplasmic reticulum transmembrane protein TMTC3 contributes to O-mannosylation of E-cadherin, cellular adherence, and embryonic gastrulation. Mol Biol Cell 2020; 31:167-183. [PMID: 31851597 PMCID: PMC7001481 DOI: 10.1091/mbc.e19-07-0408] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 10/29/2019] [Accepted: 12/12/2019] [Indexed: 01/17/2023] Open
Abstract
Protein glycosylation plays essential roles in protein structure, stability, and activity such as cell adhesion. The cadherin superfamily of adhesion molecules carry O-linked mannose glycans at conserved sites and it was recently demonstrated that the transmembrane and tetratricopeptide repeat-containing proteins 1-4 (TMTC1-4) gene products contribute to the addition of these O-linked mannoses. Here, biochemical, cell biological, and organismal analysis was used to determine that TMTC3 supports the O-mannosylation of E-cadherin, cellular adhesion, and embryonic gastrulation. Using genetically engineered cells lacking all four TMTC genes, overexpression of TMTC3 rescued O-linked glycosylation of E-cadherin and cell adherence. The knockdown of the Tmtcs in Xenopus laevis embryos caused a delay in gastrulation that was rescued by the addition of human TMTC3. Mutations in TMTC3 have been linked to neuronal cell migration diseases including Cobblestone lissencephaly. Analysis of TMTC3 mutations associated with Cobblestone lissencephaly found that three of the variants exhibit reduced stability and missence mutations were unable to complement TMTC3 rescue of gastrulation in Xenopus embryo development. Our study demonstrates that TMTC3 regulates O-linked glycosylation and cadherin-mediated adherence, providing insight into its effect on cellular adherence and migration, as well the basis of TMTC3-associated Cobblestone lissencephaly.
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Affiliation(s)
- Jill B. Graham
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, Amherst, MA 01003
- Program in Molecular and Cellular Biology, University of Massachusetts, Amherst, Amherst, MA 01003
| | - Johan C. Sunryd
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, Amherst, MA 01003
- Program in Molecular and Cellular Biology, University of Massachusetts, Amherst, Amherst, MA 01003
| | - Ketan Mathavan
- Program in Molecular and Cellular Biology, University of Massachusetts, Amherst, Amherst, MA 01003
- Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, Amherst, MA 01003
| | - Emma Weir
- Program in Molecular and Cellular Biology, University of Massachusetts, Amherst, Amherst, MA 01003
- Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, Amherst, MA 01003
| | - Ida Signe Bohse Larsen
- Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen 2200, Denmark
- Copenhagen Center for Glycomics, University of Copenhagen, Copenhagen 2200, Denmark
| | - Adnan Halim
- Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen 2200, Denmark
- Copenhagen Center for Glycomics, University of Copenhagen, Copenhagen 2200, Denmark
| | - Henrik Clausen
- Department of Cellular and Molecular Medicine, University of Copenhagen, Copenhagen 2200, Denmark
- Copenhagen Center for Glycomics, University of Copenhagen, Copenhagen 2200, Denmark
| | - Hélène Cousin
- Program in Molecular and Cellular Biology, University of Massachusetts, Amherst, Amherst, MA 01003
- Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, Amherst, MA 01003
| | - Dominque Alfandari
- Program in Molecular and Cellular Biology, University of Massachusetts, Amherst, Amherst, MA 01003
- Department of Veterinary and Animal Sciences, University of Massachusetts, Amherst, Amherst, MA 01003
| | - Daniel N. Hebert
- Department of Biochemistry and Molecular Biology, University of Massachusetts, Amherst, Amherst, MA 01003
- Program in Molecular and Cellular Biology, University of Massachusetts, Amherst, Amherst, MA 01003
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25
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Graham JB, Canniff NP, Hebert DN. TPR-containing proteins control protein organization and homeostasis for the endoplasmic reticulum. Crit Rev Biochem Mol Biol 2019; 54:103-118. [PMID: 31023093 DOI: 10.1080/10409238.2019.1590305] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The endoplasmic reticulum (ER) is a complex, multifunctional organelle comprised of a continuous membrane and lumen that is organized into a number of functional regions. It plays various roles including protein translocation, folding, quality control, secretion, calcium signaling, and lipid biogenesis. Cellular protein homeostasis is maintained by a complicated chaperone network, and the largest functional family within this network consists of proteins containing tetratricopeptide repeats (TPRs). TPRs are well-studied structural motifs that mediate intermolecular protein-protein interactions, supporting interactions with a wide range of ligands or substrates. Seven TPR-containing proteins have thus far been shown to localize to the ER and control protein organization and homeostasis within this multifunctional organelle. Here, we discuss the roles of these proteins in controlling ER processes and organization. The crucial roles that TPR-containing proteins play in the ER are highlighted by diseases or defects associated with their mutation or disruption.
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Affiliation(s)
- Jill B Graham
- a Molecular Cellular Biology Program , University of Massachusetts , Amherst , MA , USA.,b Biochemistry and Molecular Biology Department , University of Massachusetts , Amherst , MA , USA
| | - Nathan P Canniff
- a Molecular Cellular Biology Program , University of Massachusetts , Amherst , MA , USA.,b Biochemistry and Molecular Biology Department , University of Massachusetts , Amherst , MA , USA
| | - Daniel N Hebert
- a Molecular Cellular Biology Program , University of Massachusetts , Amherst , MA , USA.,b Biochemistry and Molecular Biology Department , University of Massachusetts , Amherst , MA , USA
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26
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Larsen ISB, Narimatsu Y, Clausen H, Joshi HJ, Halim A. Multiple distinct O-Mannosylation pathways in eukaryotes. Curr Opin Struct Biol 2019; 56:171-178. [PMID: 30999272 DOI: 10.1016/j.sbi.2019.03.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 02/26/2019] [Accepted: 03/01/2019] [Indexed: 12/29/2022]
Abstract
Protein O-mannosylation (O-Man), originally discovered in yeast five decades ago, is an important post-translational modification (PTM) conserved from bacteria to humans, but not found in plants or nematodes. Until recently, the homologous family of ER-located protein O-mannosyl transferases (PMT1-7 in yeast; POMT1/POMT2 in humans), were the only known enzymes involved in directing O-Man biosynthesis in eukaryotes. However, recent studies demonstrate the existence of multiple distinct O-Man glycosylation pathways indicating that the genetic and biosynthetic regulation of O-Man in eukaryotes is more complex than previously envisioned. Introduction of sensitive glycoproteomics strategies provided an expansion of O-Man glycoproteomes in eukaryotes (yeast and mammalian cell lines) leading to the discovery of O-Man glycosylation on important mammalian cell adhesion (cadherin superfamily) and signaling (plexin family) macromolecules, and to the discovery of unique nucleocytoplasmic O-Man glycosylation in yeast. It is now evident that eukaryotes have multiple distinct O-Man glycosylation pathways including: i) the classical PMT1-7 and POMT1/POMT2 pathway conserved in all eukaryotes apart from plants; ii) a yet uncharacterized nucleocytoplasmic pathway only found in yeast; iii) an ER-located pathway directed by the TMTC1-4 genes found in metazoans and protists and primarily dedicated to the cadherin superfamily; and iv) a yet uncharacterized pathway found in metazoans primarily dedicated to plexins. O-Man glycosylation is thus emerging as a much more widespread and evolutionary diverse PTM with complex genetic and biosynthetic regulation. While deficiencies in the POMT1/POMT2 O-Man pathway underlie muscular dystrophies, the TMTC1-4 pathway appear to be involved in distinct congenital disorders with neurodevelopmental phenotypes. Here, we review and discuss the recent discoveries of the new non-classical O-Man glycosylation pathways, their substrates, functions and roles in disease.
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Affiliation(s)
- Ida Signe Bohse Larsen
- Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark
| | - Yoshiki Narimatsu
- Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark
| | - Henrik Clausen
- Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark
| | - Hiren J Joshi
- Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark.
| | - Adnan Halim
- Copenhagen Center for Glycomics, Departments of Cellular and Molecular Medicine, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen N, Denmark.
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27
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Mir YR, Kuchay RAH. Advances in identification of genes involved in autosomal recessive intellectual disability: a brief review. J Med Genet 2019; 56:567-573. [PMID: 30842223 DOI: 10.1136/jmedgenet-2018-105821] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2018] [Revised: 02/01/2019] [Accepted: 02/11/2019] [Indexed: 12/28/2022]
Abstract
Intellectual disability (ID) is a clinically and genetically heterogeneous disorder, affecting 1%-3% of the general population. The number of ID-causing genes is high. Many X-linked genes have been implicated in ID. Autosomal dominant genes have recently been the focus of several large-scale studies. The total number of autosomal recessive ID (ARID) genes is estimated to be very high, and most are still unknown. Although research into the genetic causes of ID has recently gained momentum, identification of pathogenic mutations that cause ARID has lagged behind, predominantly due to non-availability of sizeable families. A commonly used approach to identify genetic loci for recessive disorders in consanguineous families is autozygosity mapping and whole-exome sequencing. Combination of these two approaches has recently led to identification of many genes involved in ID. These genes have diverse function and control various biological processes. In this review, we will present an update regarding genes that have been recently implicated in ID with focus on ARID.
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Affiliation(s)
- Yaser Rafiq Mir
- Department of Biotechnology, Baba Ghulam Shah Badshah University, Rajouri, Jammu and Kashmir, India
| | - Raja Amir Hassan Kuchay
- Department of Biotechnology, Baba Ghulam Shah Badshah University, Rajouri, Jammu and Kashmir, India
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28
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van Tol W, Wessels H, Lefeber DJ. O-glycosylation disorders pave the road for understanding the complex human O-glycosylation machinery. Curr Opin Struct Biol 2019; 56:107-118. [PMID: 30708323 DOI: 10.1016/j.sbi.2018.12.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Revised: 12/16/2018] [Accepted: 12/18/2018] [Indexed: 01/17/2023]
Abstract
Over 100 human Congenital Disorders of Glycosylation (CDG) have been described. Of these, about 30% reside in the O-glycosylation pathway. O-glycosylation disorders are characterized by a high phenotypic variability, reflecting the large diversity of O-glycan structures. In contrast to N-glycosylation disorders, a generic biochemical screening test is lacking, which limits the identification of novel O-glycosylation disorders. The emergence of next generation sequencing (NGS) and O-glycoproteomics technologies have changed this situation, resulting in significant progress to link disease phenotypes with underlying biochemical mechanisms. Here, we review the current knowledge on O-glycosylation disorders, and discuss the biochemical lessons that we can learn on 1) novel glycosyltransferases and metabolic pathways, 2) tissue-specific O-glycosylation mechanisms, 3) O-glycosylation targets and 4) structure-function relationships. Additionally, we provide an outlook on how genetic disorders, O-glycoproteomics and biochemical methods can be combined to answer fundamental questions regarding O-glycan synthesis, structure and function.
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Affiliation(s)
- Walinka van Tol
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, The Netherlands; Translational Metabolic Laboratory, Department of Laboratory Medicine, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Hans Wessels
- Translational Metabolic Laboratory, Department of Laboratory Medicine, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Dirk J Lefeber
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Nijmegen, The Netherlands; Translational Metabolic Laboratory, Department of Laboratory Medicine, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Nijmegen, The Netherlands.
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29
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Buchsbaum IY, Cappello S. Neuronal migration in the CNS during development and disease: insights from in vivo and in vitro models. Development 2019; 146:146/1/dev163766. [DOI: 10.1242/dev.163766] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
ABSTRACT
Neuronal migration is a fundamental process that governs embryonic brain development. As such, mutations that affect essential neuronal migration processes lead to severe brain malformations, which can cause complex and heterogeneous developmental and neuronal migration disorders. Our fragmented knowledge about the aetiology of these disorders raises numerous issues. However, many of these can now be addressed through studies of in vivo and in vitro models that attempt to recapitulate human-specific mechanisms of cortical development. In this Review, we discuss the advantages and limitations of these model systems and suggest that a complementary approach, using combinations of in vivo and in vitro models, will broaden our knowledge of the molecular and cellular mechanisms that underlie defective neuronal positioning in the human cerebral cortex.
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Affiliation(s)
- Isabel Yasmin Buchsbaum
- Developmental Neurobiology, Max Planck Institute of Psychiatry, 80804 Munich, Germany
- Graduate School of Systemic Neurosciences, Ludwig-Maximilians-University Munich, 82152 Planegg, Germany
| | - Silvia Cappello
- Developmental Neurobiology, Max Planck Institute of Psychiatry, 80804 Munich, Germany
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30
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How Surrogate and Chemical Genetics in Model Organisms Can Suggest Therapies for Human Genetic Diseases. Genetics 2018; 208:833-851. [PMID: 29487144 PMCID: PMC5844338 DOI: 10.1534/genetics.117.300124] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Accepted: 12/26/2017] [Indexed: 12/12/2022] Open
Abstract
Genetic diseases are both inherited and acquired. Many genetic diseases fall under the paradigm of orphan diseases, a disease found in < 1 in 2000 persons. With rapid and cost-effective genome sequencing becoming the norm, many causal mutations for genetic diseases are being rapidly determined. In this regard, model organisms are playing an important role in validating if specific mutations identified in patients drive the observed phenotype. An emerging challenge for model organism researchers is the application of genetic and chemical genetic platforms to discover drug targets and drugs/drug-like molecules for potential treatment options for patients with genetic disease. This review provides an overview of how model organisms have contributed to our understanding of genetic disease, with a focus on the roles of yeast and zebrafish in gene discovery and the identification of compounds that could potentially treat human genetic diseases.
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31
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Oriel C, Lasko P. Recent Developments in Using Drosophila as a Model for Human Genetic Disease. Int J Mol Sci 2018; 19:E2041. [PMID: 30011838 PMCID: PMC6073706 DOI: 10.3390/ijms19072041] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 07/09/2018] [Accepted: 07/10/2018] [Indexed: 12/11/2022] Open
Abstract
Many insights into human disease have been built on experimental results in Drosophila, and research in fruit flies is often justified on the basis of its predictive value for questions related to human health. Additionally, there is now a growing recognition of the value of Drosophila for the study of rare human genetic diseases, either as a means of validating the causative nature of a candidate genetic variant found in patients, or as a means of obtaining functional information about a novel disease-linked gene when there is little known about it. For these reasons, funders in the US, Europe, and Canada have launched targeted programs to link human geneticists working on discovering new rare disease loci with researchers who work on the counterpart genes in Drosophila and other model organisms. Several of these initiatives are described here, as are a number of output publications that validate this new approach.
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Affiliation(s)
- Christine Oriel
- Maternal Infant Child Youth and Research Network, V2-230, 950 West 28th Ave, Vancouver, BC V5Z 4H4, Canada.
| | - Paul Lasko
- Department of Biology, McGill University, 3649 Promenade Sir-William-Osler, Montreal, QC H3G 0B1, Canada.
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32
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Wang LR, Radonjic A, Dilliott AA, McIntyre AD, Hegele RA. A De Novo POLD1 Mutation Associated With Mandibular Hypoplasia, Deafness, Progeroid Features, and Lipodystrophy Syndrome in a Family With Werner Syndrome. J Investig Med High Impact Case Rep 2018; 6:2324709618786770. [PMID: 30023403 PMCID: PMC6047234 DOI: 10.1177/2324709618786770] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Revised: 05/28/2018] [Accepted: 06/12/2018] [Indexed: 11/15/2022] Open
Abstract
Background. Mandibular hypoplasia, deafness, progeroid features, and lipodystrophy (MDPL) syndrome is a recently recognized genetic disorder comprised of mandibular hypoplasia, deafness, progeroid features, and lipodystrophy. It is caused by an autosomal dominant mutation in the POLD1 gene, with <20 genetically confirmed cases to date. Clinical overlap with other progeroid syndromes including Werner syndrome (WS) can present diagnostic challenges. Case. The proband is a 36-year-old male of Sicilian ancestry who was phenotypically normal at birth. Onset of lipodystrophic and progeroid features began at 18 months, with progressive loss of subcutaneous fat, prominent eyes, and pinched nose. Over the next 2 decades, he developed hearing loss, small fingers, joint contractures, hypogonadism, osteoporosis, and hypertriglyceridemia. Three of his 4 siblings had premature hair graying and loss, severe bilateral cataracts, skin changes, and varying degrees of age-related metabolic conditions, raising suspicion for a genetic progeroid syndrome. Genetic Analysis. A targeted sequencing panel identified a heterozygous WRN mutation in the proband’s genomic DNA. Sanger sequencing further revealed his parents and an asymptomatic brother to be carriers of this mutation, and in his 3 brothers affected with classic WS the mutation was identified in the homozygous state. Whole exome sequencing ultimately revealed the proband harbored the causative de novo in-frame deletion in POLD1 (p.Ser605del), which is the most common mutation in MDPL patients. Conclusion. We report the unusual convergence of 2 rare progeroid disorders in the same family: the proband displayed sporadic MDPL syndrome, while 3 brothers had classical autosomal recessive WS. Whole exome sequencing was invaluable in clarifying the molecular diagnoses in this family.
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Discovery of an O-mannosylation pathway selectively serving cadherins and protocadherins. Proc Natl Acad Sci U S A 2017; 114:11163-11168. [PMID: 28973932 DOI: 10.1073/pnas.1708319114] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The cadherin (cdh) superfamily of adhesion molecules carry O-linked mannose (O-Man) glycans at highly conserved sites localized to specific β-strands of their extracellular cdh (EC) domains. These O-Man glycans do not appear to be elongated like O-Man glycans found on α-dystroglycan (α-DG), and we recently demonstrated that initiation of cdh/protocadherin (pcdh) O-Man glycosylation is not dependent on the evolutionary conserved POMT1/POMT2 enzymes that initiate O-Man glycosylation on α-DG. Here, we used a CRISPR/Cas9 genetic dissection strategy combined with sensitive and quantitative O-Man glycoproteomics to identify a homologous family of four putative protein O-mannosyltransferases encoded by the TMTC1-4 genes, which were found to be imperative for cdh and pcdh O-Man glycosylation. KO of all four TMTC genes in HEK293 cells resulted in specific loss of cdh and pcdh O-Man glycosylation, whereas combined KO of TMTC1 and TMTC3 resulted in selective loss of O-Man glycans on specific β-strands of EC domains, suggesting that each isoenzyme serves a different function. In addition, O-Man glycosylation of IPT/TIG domains of plexins and hepatocyte growth factor receptor was not affected in TMTC KO cells, suggesting the existence of yet another O-Man glycosylation machinery. Our study demonstrates that regulation of O-mannosylation in higher eukaryotes is more complex than envisioned, and the discovery of the functions of TMTCs provide insight into cobblestone lissencephaly caused by deficiency in TMTC3.
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