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Gerashchenko T, Skitchenko R, Korobeynikova A, Kuanysheva K, Khozyainova A, Vorobiev R, Rodionov E, Miller S, Topolnitsky E, Shefer N, Anisimenko M, Zhuikova L, Vashisth M, Pankova O, Perelmuter V, Rezapova V, Artomov M, Denisov E. Whole-exome sequencing reveals an association of rs112065068 in TGOLN2 gene with distant metastasis of non-small cell lung cancer. Gene 2024; 920:148507. [PMID: 38670394 DOI: 10.1016/j.gene.2024.148507] [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: 02/19/2024] [Revised: 04/01/2024] [Accepted: 04/23/2024] [Indexed: 04/28/2024]
Abstract
Early prediction and prevention of recurring illness is critical for improving the survival rates of patients with non-small cell lung cancer (NSCLC). Previously, we demonstrated that the presence of premalignant epithelial changes in the small bronchi distant to the primary tumor is associated with NSCLC progression: isolated basal cell hyperplasia (iBCH) indicates a high risk of distant metastasis, BCH combined with squamous metaplasia (BCHSM) - a high risk of locoregional recurrence. Here, we aimed to identify germline single nucleotide variants (SNVs) and insertions and deletions (InDels) associated with distant metastasis and locoregional recurrence in cases with iBCH and BCHSM using whole-exome sequencing of 172 NSCLC patients. The rs112065068 of the TGOLN2 gene was identified only in iBCH patients and was associated with a high risk of distant metastasis (P < .001) and worse metastasis-free survival (HR = 4.19 (95 %CI 1.97-8.93); P < .001). This variant was validated in a group of 109 NSCLC patients using real-time PCR and Sanger sequencing analyses. To our knowledge, this study is the first to identify a germline variant associated with NSCLC distant metastasis.
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Affiliation(s)
- Tatiana Gerashchenko
- Laboratory of Cancer Progression Biology, Cancer Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, Kooperativny Str. 5, Tomsk 634009, Russia; Laboratory of Single Cell Biology, Research Institute of Molecular and Cellular Medicine, Peoples' Friendship University of Russia (RUDN University), Miklukho-Maklaya Str. 6, Moscow 117198, Russia
| | | | - Anastasia Korobeynikova
- Laboratory of Cancer Progression Biology, Cancer Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, Kooperativny Str. 5, Tomsk 634009, Russia; Laboratory of Single Cell Biology, Research Institute of Molecular and Cellular Medicine, Peoples' Friendship University of Russia (RUDN University), Miklukho-Maklaya Str. 6, Moscow 117198, Russia
| | - Kristina Kuanysheva
- Laboratory of Cancer Progression Biology, Cancer Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, Kooperativny Str. 5, Tomsk 634009, Russia
| | - Anna Khozyainova
- Laboratory of Cancer Progression Biology, Cancer Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, Kooperativny Str. 5, Tomsk 634009, Russia
| | - Rostislav Vorobiev
- Laboratory of Cancer Progression Biology, Cancer Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, Kooperativny Str. 5, Tomsk 634009, Russia
| | - Evgeny Rodionov
- Department of Thoracic Oncology, Cancer Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, Kooperativny Str. 5, Tomsk 634009, Russia
| | - Sergey Miller
- Department of Thoracic Oncology, Cancer Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, Kooperativny Str. 5, Tomsk 634009, Russia
| | - Evgeny Topolnitsky
- Department of Surgery with a Course of Mobilization Training and Disaster Medicine, Siberian State Medical University, Moskovskiy Tract 2, Tomsk 634050, Russia
| | - Nikolay Shefer
- Department of Surgery with a Course of Mobilization Training and Disaster Medicine, Siberian State Medical University, Moskovskiy Tract 2, Tomsk 634050, Russia
| | - Maxim Anisimenko
- Federal Research Center Institute of Cytology and Genetics, Siberian Branch of Russian Academy of Sciences, Ac. Lavrentieva Ave. 10, Novosibirsk 630090, Russia
| | - Lilia Zhuikova
- Laboratory of Epidemiology, Cancer Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, Kooperativny Str. 5, Tomsk 634009, Russia
| | - Mrinal Vashisth
- Tomsk State University, Lenina Ave. 36, Tomsk 634050, Russia
| | - Olga Pankova
- Department of General and Molecular Pathology, Cancer Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, Kooperativny Str. 5, Tomsk 634009, Russia
| | - Vladimir Perelmuter
- Department of General and Molecular Pathology, Cancer Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, Kooperativny Str. 5, Tomsk 634009, Russia
| | - Valeria Rezapova
- ITMO, Kronverksky Pr. 49, Bldg. A, St. Petersburg, 197101, Russia; University Cote D'Azur, Grand Château 28 Avenue de Valrose, Nice 06103, France
| | - Mykyta Artomov
- The Steve and Cindy Rasmussen Institute for Genomic Medicine, Nationwide Children's Hospital, Columbus, OH 43205, USA; Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH 43215, USA
| | - Evgeny Denisov
- Laboratory of Cancer Progression Biology, Cancer Research Institute, Tomsk National Research Medical Center, Russian Academy of Sciences, Kooperativny Str. 5, Tomsk 634009, Russia; Laboratory of Single Cell Biology, Research Institute of Molecular and Cellular Medicine, Peoples' Friendship University of Russia (RUDN University), Miklukho-Maklaya Str. 6, Moscow 117198, Russia.
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Brockmöller S, Worek F, Rothmiller S. Protein networking: nicotinic acetylcholine receptors and their protein-protein-associations. Mol Cell Biochem 2024:10.1007/s11010-024-05032-x. [PMID: 38771378 DOI: 10.1007/s11010-024-05032-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Accepted: 05/04/2024] [Indexed: 05/22/2024]
Abstract
Nicotinic acetylcholine receptors (nAChR) are complex transmembrane proteins involved in neurotransmission in the nervous system and at the neuromuscular junction. nAChR disorders may lead to severe, potentially fatal pathophysiological states. To date, the receptor has been the focus of basic and applied research to provide novel therapeutic interventions. Since most studies have investigated only the nAChR itself, it is necessary to consider the receptor as part of its protein network to understand or elucidate-specific pathways. On its way through the secretory pathway, the receptor interacts with several chaperones and proteins. This review takes a closer look at these molecular interactions and focuses especially on endoplasmic reticulum biogenesis, secretory pathway sorting, Golgi maturation, plasma membrane presentation, retrograde internalization, and recycling. Additional knowledge regarding the nAChR protein network may lead to a more detailed comprehension of the fundamental pathomechanisms of diseases or may lead to the discovery of novel therapeutic drug targets.
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Affiliation(s)
- Sabrina Brockmöller
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Bavaria, Germany.
| | - Franz Worek
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Bavaria, Germany
| | - Simone Rothmiller
- Bundeswehr Institute of Pharmacology and Toxicology, Munich, Bavaria, Germany
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3
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G. Dornan L, C. Simpson J. Rab6-mediated retrograde trafficking from the Golgi: the trouble with tubules. Small GTPases 2023; 14:26-44. [PMID: 37488775 PMCID: PMC10392741 DOI: 10.1080/21541248.2023.2238330] [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: 06/15/2023] [Revised: 07/13/2023] [Accepted: 07/15/2023] [Indexed: 07/26/2023] Open
Abstract
Next year marks one-quarter of a century since the discovery of the so-called COPI-independent pathway, which operates between the Golgi apparatus and the endoplasmic reticulum (ER) in eukaryotic cells. Unlike almost all other intracellular trafficking pathways, this pathway is not regulated by the physical accumulation of multisubunit proteinaceous coat molecules, but instead by the small GTPase Rab6. What also sets it apart from other pathways is that the transport carriers themselves often take the form of tubules, rather than conventional vesicles. In this review, we assess the relevant literature that has accumulated to date, in an attempt to provide a concerted description of how this pathway is regulated. We discuss the possible cargo molecules that are carried in this pathway, and the likely mechanism of Rab6 tubule biogenesis, including how the cargo itself may play a critical role. We also provide perspective surrounding the various molecular motors of the kinesin, myosin and dynein families that have been implicated in driving Rab6-coated tubular membranes long distances through the cell prior to delivering their cargo to the ER. Finally, we also raise several important questions that require resolution, if we are to ultimately provide a comprehensive molecular description of how the COPI-independent pathway is controlled.
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Affiliation(s)
- Lucy G. Dornan
- Cell Screening Laboratory, UCD School of Biology & Environmental Science, University College Dublin, Dublin, Ireland
| | - Jeremy C. Simpson
- Cell Screening Laboratory, UCD School of Biology & Environmental Science, University College Dublin, Dublin, Ireland
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Marsilia C, Batra M, Pokrovskaya ID, Wang C, Chaput D, Naumova DA, Lupashin VV, Suvorova ES. Essential role of the conserved oligomeric Golgi complex in Toxoplasma gondii. mBio 2023; 14:e0251323. [PMID: 37966241 PMCID: PMC10746232 DOI: 10.1128/mbio.02513-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 10/05/2023] [Indexed: 11/16/2023] Open
Abstract
IMPORTANCE The Golgi is an essential eukaryotic organelle and a major place for protein sorting and glycosylation. Among apicomplexan parasites, Toxoplasma gondii retains the most developed Golgi structure and produces many glycosylated factors necessary for parasite survival. Despite its importance, Golgi function received little attention in the past. In the current study, we identified and characterized the conserved oligomeric Golgi complex and its novel partners critical for protein transport in T. gondii tachyzoites. Our results suggest that T. gondii broadened the role of the conserved elements and reinvented the missing components of the trafficking machinery to accommodate the specific needs of the opportunistic parasite T. gondii.
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Affiliation(s)
- Clem Marsilia
- Division of Infectious Diseases, Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - Mrinalini Batra
- Division of Infectious Diseases, Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - Irina D. Pokrovskaya
- Department of Physiology and Cell Biology, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Changqi Wang
- College of Public Health, University of South Florida, Tampa, Florida, USA
| | - Dale Chaput
- Proteomics Core, College of Arts and Sciences, University of South Florida, Tampa, Florida, USA
| | - Daria A. Naumova
- Division of Infectious Diseases, Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - Vladimir V. Lupashin
- Department of Physiology and Cell Biology, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Elena S. Suvorova
- Division of Infectious Diseases, Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
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Mohan AG, Calenic B, Ghiurau NA, Duncea-Borca RM, Constantinescu AE, Constantinescu I. The Golgi Apparatus: A Voyage through Time, Structure, Function and Implication in Neurodegenerative Disorders. Cells 2023; 12:1972. [PMID: 37566051 PMCID: PMC10417163 DOI: 10.3390/cells12151972] [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: 06/14/2023] [Revised: 07/27/2023] [Accepted: 07/29/2023] [Indexed: 08/12/2023] Open
Abstract
This comprehensive review article dives deep into the Golgi apparatus, an essential organelle in cellular biology. Beginning with its discovery during the 19th century until today's recognition as an important contributor to cell function. We explore its unique organization and structure as well as its roles in protein processing, sorting, and lipid biogenesis, which play key roles in maintaining homeostasis in cellular biology. This article further explores Golgi biogenesis, exploring its intricate processes and dynamics that contribute to its formation and function. One key focus is its role in neurodegenerative diseases like Parkinson's, where changes to the structure or function of the Golgi apparatus may lead to their onset or progression, emphasizing its key importance in neuronal health. At the same time, we examine the intriguing relationship between Golgi stress and endoplasmic reticulum (ER) stress, providing insights into their interplay as two major cellular stress response pathways. Such interdependence provides a greater understanding of cellular reactions to protein misfolding and accumulation, hallmark features of many neurodegenerative diseases. In summary, this review offers an exhaustive examination of the Golgi apparatus, from its historical background to its role in health and disease. Additionally, this examination emphasizes the necessity of further research in this field in order to develop targeted therapeutic approaches for Golgi dysfunction-associated conditions. Furthermore, its exploration is an example of scientific progress while simultaneously offering hope for developing innovative treatments for neurodegenerative disorders.
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Affiliation(s)
- Aurel George Mohan
- Department of Neurosurgery, Bihor County Emergency Clinical Hospital, 410167 Oradea, Romania;
- Faculty of Medicine, Oradea University, 410610 Oradea, Romania
| | - Bogdan Calenic
- Immunology and Transplant Immunology, Carol Davila University of Medicine and Pharmacy, 020021 Bucharest, Romania;
- Centre of Immunogenetics and Virology, Fundeni Clinical Institute, 022328 Bucharest, Romania
| | - Nicu Adrian Ghiurau
- Department of Surgical Disciplines, Faculty of Medicine and Pharmacy, University of Oradea, 410610 Oradea, Romania;
| | | | | | - Ileana Constantinescu
- Immunology and Transplant Immunology, Carol Davila University of Medicine and Pharmacy, 020021 Bucharest, Romania;
- Centre of Immunogenetics and Virology, Fundeni Clinical Institute, 022328 Bucharest, Romania
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6
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Sumya FT, Pokrovskaya ID, Lupashin VV. Rapid COG Depletion in Mammalian Cell by Auxin-Inducible Degradation System. Methods Mol Biol 2023; 2557:365-390. [PMID: 36512227 PMCID: PMC10019459 DOI: 10.1007/978-1-0716-2639-9_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Conserved oligomeric Golgi (COG) complex orchestrates intra-Golgi retrograde trafficking and glycosylation of macromolecules, but the detailed mechanism of COG action is unknown. Previous studies employed prolonged protein knockout and knockdown approaches which may potentially generate off-target and indirect mutant phenotypes. To achieve a fast depletion of COG subunits in human cells, the auxin-inducible degradation system was employed. This method of protein regulation allows a very fast and efficient depletion of COG subunits, which provides the ability to accumulate COG complex dependent (CCD) vesicles and investigate initial cellular defects associated with the acute depletion of COG complex subunits. This protocol is applicable to other vesicle tethering complexes and can be utilized to investigate anterograde and retrograde intracellular membrane trafficking pathways.
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Affiliation(s)
- Farhana Taher Sumya
- Department of Physiology and Cell Biology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Irina D Pokrovskaya
- Department of Physiology and Cell Biology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Vladimir V Lupashin
- Department of Physiology and Cell Biology, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
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7
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Rui Q, Tan X, Liu F, Bao Y. An Update on the Key Factors Required for Plant Golgi Structure Maintenance. FRONTIERS IN PLANT SCIENCE 2022; 13:933283. [PMID: 35837464 PMCID: PMC9274083 DOI: 10.3389/fpls.2022.933283] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Accepted: 05/30/2022] [Indexed: 06/15/2023]
Abstract
Plant Golgi apparatus serves as the central station of the secretory pathway and is the site where protein modification and cell wall matrix polysaccharides synthesis occur. The polarized and stacked cisternal structure is a prerequisite for Golgi function. Our understanding of Golgi structure maintenance and trafficking are largely obtained from mammals and yeast, yet, plant Golgi has many different aspects. In this review, we summarize the key players in Golgi maintenance demonstrated by genetic studies in plants, which function in ER-Golgi, intra-Golgi and post-Golgi transport pathways. Among these, we emphasize on players in intra-Golgi trafficking.
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8
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Wang S, Ma C. Neuronal SNARE complex assembly guided by Munc18-1 and Munc13-1. FEBS Open Bio 2022; 12:1939-1957. [PMID: 35278279 PMCID: PMC9623535 DOI: 10.1002/2211-5463.13394] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Revised: 02/28/2022] [Accepted: 03/10/2022] [Indexed: 01/25/2023] Open
Abstract
Neurotransmitter release by Ca2+ -triggered synaptic vesicle exocytosis is essential for information transmission in the nervous system. The soluble N-ethylmaleimide sensitive factor attachment protein receptors (SNAREs) syntaxin-1, SNAP-25, and synaptobrevin-2 form the SNARE complex to bring synaptic vesicles and the plasma membranes together and to catalyze membrane fusion. Munc18-1 and Munc13-1 regulate synaptic vesicle priming via orchestrating neuronal SNARE complex assembly. In this review, we summarize recent advances toward the functions and molecular mechanisms of Munc18-1 and Munc13-1 in guiding neuronal SNARE complex assembly, and discuss the functional similarities and differences between Munc18-1 and Munc13-1 in neurons and their homologs in other intracellular membrane trafficking systems.
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Affiliation(s)
- Shen Wang
- Key Laboratory of Molecular Biophysics of the Ministry of EducationCollege of Life Science and TechnologyHuazhong University of Science and TechnologyWuhanChina
| | - Cong Ma
- Key Laboratory of Molecular Biophysics of the Ministry of EducationCollege of Life Science and TechnologyHuazhong University of Science and TechnologyWuhanChina
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9
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D’Souza Z, Sumya FT, Khakurel A, Lupashin V. Getting Sugar Coating Right! The Role of the Golgi Trafficking Machinery in Glycosylation. Cells 2021; 10:cells10123275. [PMID: 34943782 PMCID: PMC8699264 DOI: 10.3390/cells10123275] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 11/17/2021] [Accepted: 11/19/2021] [Indexed: 12/18/2022] Open
Abstract
The Golgi is the central organelle of the secretory pathway and it houses the majority of the glycosylation machinery, which includes glycosylation enzymes and sugar transporters. Correct compartmentalization of the glycosylation machinery is achieved by retrograde vesicular trafficking as the secretory cargo moves forward by cisternal maturation. The vesicular trafficking machinery which includes vesicular coats, small GTPases, tethers and SNAREs, play a major role in coordinating the Golgi trafficking thereby achieving Golgi homeostasis. Glycosylation is a template-independent process, so its fidelity heavily relies on appropriate localization of the glycosylation machinery and Golgi homeostasis. Mutations in the glycosylation enzymes, sugar transporters, Golgi ion channels and several vesicle tethering factors cause congenital disorders of glycosylation (CDG) which encompass a group of multisystem disorders with varying severities. Here, we focus on the Golgi vesicle tethering and fusion machinery, namely, multisubunit tethering complexes and SNAREs and their role in Golgi trafficking and glycosylation. This review is a comprehensive summary of all the identified CDG causing mutations of the Golgi trafficking machinery in humans.
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Focus on the Small GTPase Rab1: A Key Player in the Pathogenesis of Parkinson's Disease. Int J Mol Sci 2021; 22:ijms222112087. [PMID: 34769517 PMCID: PMC8584362 DOI: 10.3390/ijms222112087] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 11/04/2021] [Accepted: 11/06/2021] [Indexed: 12/19/2022] Open
Abstract
Parkinson’s disease (PD) is the second most frequent neurodegenerative disease. It is characterized by the loss of dopaminergic neurons in the substantia nigra and the formation of large aggregates in the survival neurons called Lewy bodies, which mainly contain α-synuclein (α-syn). The cause of cell death is not known but could be due to mitochondrial dysfunction, protein homeostasis failure, and alterations in the secretory/endolysosomal/autophagic pathways. Survival nigral neurons overexpress the small GTPase Rab1. This protein is considered a housekeeping Rab that is necessary to support the secretory pathway, the maintenance of the Golgi complex structure, and the regulation of macroautophagy from yeast to humans. It is also involved in signaling, carcinogenesis, and infection for some pathogens. It has been shown that it is directly linked to the pathogenesis of PD and other neurodegenerative diseases. It has a protective effect against α–σψν toxicity and has recently been shown to be a substrate of LRRK2, which is the most common cause of familial PD and the risk of sporadic disease. In this review, we analyze the key aspects of Rab1 function in dopamine neurons and its implications in PD neurodegeneration/restauration. The results of the current and former research support the notion that this GTPase is a good candidate for therapeutic strategies.
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11
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Sumya FT, Pokrovskaya ID, Lupashin V. Development and Initial Characterization of Cellular Models for COG Complex-Related CDG-II Diseases. Front Genet 2021; 12:733048. [PMID: 34603392 PMCID: PMC8484713 DOI: 10.3389/fgene.2021.733048] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 09/06/2021] [Indexed: 12/12/2022] Open
Abstract
Conserved Oligomeric Golgi (COG) is an octameric protein complex that orchestrates intra-Golgi trafficking of glycosylation enzymes. Over a hundred individuals with 31 different COG mutations have been identified until now. The cellular phenotypes and clinical presentations of COG-CDGs are heterogeneous, and patients primarily represent neurological, skeletal, and hepatic abnormalities. The establishment of a cellular COG disease model will benefit the molecular study of the disease, explaining the detailed sequence of the interplay between the COG complex and the trafficking machinery. Moreover, patient fibroblasts are not a good representative of all the organ systems and cell types that are affected by COG mutations. We developed and characterized cellular models for human COG4 mutations, specifically in RPE1 and HEK293T cell lines. Using a combination of CRISPR/Cas9 and lentiviral transduction technologies, both myc-tagged wild-type and mutant (G516R and R729W) COG4 proteins were expressed under the endogenous COG4 promoter. Constructed isogenic cell lines were comprehensively characterized using biochemical, microscopy (superresolution and electron), and proteomics approaches. The analysis revealed similar stability and localization of COG complex subunits, wild-type cell growth, and normal Golgi morphology in all three cell lines. Importantly, COG4-G516R cells demonstrated increased HPA-647 binding to the plasma membrane glycoconjugates, while COG4-R729W cells revealed high GNL-647 binding, indicating specific defects in O- and N-glycosylation. Both mutant cell lines express an elevated level of heparin sulfate proteoglycans. Moreover, a quantitative mass-spectrometry analysis of proteins secreted by COG-deficient cell lines revealed abnormal secretion of SIL1 and ERGIC-53 proteins by COG4-G516R cells. Interestingly, the clinical phenotype of patients with congenital mutations in the SIL1 gene (Marinesco-Sjogren syndrome) overlaps with the phenotype of COG4-G516R patients (Saul-Wilson syndrome). Our work is the first compressive study involving the creation of different COG mutations in different cell lines other than the patient's fibroblast. It may help to address the underlying cause of the phenotypic defects leading to the discovery of a proper treatment guideline for COG-CDGs.
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Affiliation(s)
| | | | - Vladimir Lupashin
- Department of Physiology and Cell Biology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
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12
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Klink VP, Darwish O, Alkharouf NW, Lawaju BR, Khatri R, Lawrence KS. Conserved oligomeric Golgi (COG) complex genes functioning in defense are expressed in root cells undergoing a defense response to a pathogenic infection and exhibit regulation my MAPKs. PLoS One 2021; 16:e0256472. [PMID: 34437620 PMCID: PMC8389442 DOI: 10.1371/journal.pone.0256472] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Accepted: 08/06/2021] [Indexed: 12/21/2022] Open
Abstract
The conserved oligomeric Golgi (COG) complex maintains correct Golgi structure and function during retrograde trafficking. Glycine max has 2 paralogs of each COG gene, with one paralog of each gene family having a defense function to the parasitic nematode Heterodera glycines. Experiments presented here show G. max COG paralogs functioning in defense are expressed specifically in the root cells (syncytia) undergoing the defense response. The expressed defense COG gene COG7-2-b is an alternate splice variant, indicating specific COG variants are important to defense. Transcriptomic experiments examining RNA isolated from COG overexpressing and RNAi roots show some COG genes co-regulate the expression of other COG complex genes. Examining signaling events responsible for COG expression, transcriptomic experiments probing MAPK overexpressing roots show their expression influences the relative transcript abundance of COG genes as compared to controls. COG complex paralogs are shown to be found in plants that are agriculturally relevant on a world-wide scale including Manihot esculenta, Zea mays, Oryza sativa, Triticum aestivum, Hordeum vulgare, Sorghum bicolor, Brassica rapa, Elaes guineensis and Saccharum officinalis and in additional crops significant to U.S. agriculture including Beta vulgaris, Solanum tuberosum, Solanum lycopersicum and Gossypium hirsutum. The analyses provide basic information on COG complex biology, including the coregulation of some COG genes and that MAPKs functioning in defense influence their expression. Furthermore, it appears in G. max and likely other crops that some level of neofunctionalization of the duplicated genes is occurring. The analysis has identified important avenues for future research broadly in plants.
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Affiliation(s)
- Vincent P. Klink
- USDA ARS NEA BARC Molecular Plant Pathology Laboratory, Beltsville, MD, United States of America
| | - Omar Darwish
- Department of Mathematics Computer Science, Texas Woman’s University, Denton, TX, United States of America
| | - Nadim W. Alkharouf
- Department of Computer and Information Sciences, Towson University, Towson, MD, United States of America
| | - Bisho R. Lawaju
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL, United States of America
| | - Rishi Khatri
- Department of Biological Sciences, Mississippi State University, Mississippi, MS, United States of America
| | - Kathy S. Lawrence
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL, United States of America
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13
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Khakurel A, Kudlyk T, Bonifacino JS, Lupashin VV. The Golgi-associated retrograde protein (GARP) complex plays an essential role in the maintenance of the Golgi glycosylation machinery. Mol Biol Cell 2021; 32:1594-1610. [PMID: 34161137 PMCID: PMC8351751 DOI: 10.1091/mbc.e21-04-0169] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 05/24/2021] [Accepted: 06/14/2021] [Indexed: 11/18/2022] Open
Abstract
The Golgi complex is a central hub for intracellular protein trafficking and glycosylation. Steady-state localization of glycosylation enzymes is achieved by a combination of mechanisms involving retention and recycling, but the machinery governing these mechanisms is poorly understood. Herein we show that the Golgi-associated retrograde protein (GARP) complex is a critical component of this machinery. Using multiple human cell lines, we show that depletion of GARP subunits impairs Golgi modification of N- and O-glycans and reduces the stability of glycoproteins and Golgi enzymes. Moreover, GARP-knockout (KO) cells exhibit reduced retention of glycosylation enzymes in the Golgi. A RUSH assay shows that, in GARP-KO cells, the enzyme beta-1,4-galactosyltransferase 1 is not retained at the Golgi complex but instead is missorted to the endolysosomal system. We propose that the endosomal system is part of the trafficking itinerary of Golgi enzymes or their recycling adaptors and that the GARP complex is essential for recycling and stabilization of the Golgi glycosylation machinery. [Media: see text].
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Affiliation(s)
- Amrita Khakurel
- University of Arkansas for Medical Sciences, Department of Physiology and Cell Biology, Little Rock, AR 72205
| | - Tetyana Kudlyk
- University of Arkansas for Medical Sciences, Department of Physiology and Cell Biology, Little Rock, AR 72205
| | - Juan S. Bonifacino
- Neurosciences and Cellular and Structural Biology Division, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892
| | - Vladimir V. Lupashin
- University of Arkansas for Medical Sciences, Department of Physiology and Cell Biology, Little Rock, AR 72205
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14
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Adusumalli R, Åsheim HC, Lupashin V, Blackburn JB, Prydz K. Proteoglycan synthesis in conserved oligomeric Golgi subunit deficient HEK293T cells is affected differently, depending on the lacking subunit. Traffic 2021; 22:230-239. [PMID: 34053170 DOI: 10.1111/tra.12804] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 05/26/2021] [Accepted: 05/27/2021] [Indexed: 01/08/2023]
Abstract
The Conserved Oligomeric Golgi (COG) complex is an eight subunit protein complex associated with Golgi membranes. Genetic defects affecting individual COG subunits cause congenital disorders of glycosylation (CDGs), due to mislocalization of Golgi proteins involved in glycosylation mechanisms. While the resulting defects in N-and O-glycosylation have been extensively studied, no corresponding study of proteoglycan (PG) synthesis has been undertaken. We here show that glycosaminoglycan (GAG) modification of PGs is significantly reduced, regardless which COG subunit that is missing in HEK293T cells. Least reduction was observed for cells lacking COG1 and COG8 subunits, that bridge the A and B lobes of the complex. Lack of these subunits did not reduce GAG chain lengths of secreted PGs, which was reduced in cells lacking any other subunit (COG2-7). COG3 knock out (KO) cells had particularly reduced ability to polymerize GAG chains. For cell-associated GAGs, the mutant cell lines, except COG4 and COG7 KO, displayed longer GAG chains than wild-type cells, indicating that COG subunits play a role in cellular turnover of PGs. In light of the important roles PGs play in animal development, the effects KO of individual COG subunits have on GAG synthesis could explain the variable severity of COG associated CDGs.
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Affiliation(s)
| | | | - Vladimir Lupashin
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Jessica B Blackburn
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA.,Department of Medicine, Division of Allergy, Vanderbilt University Medical Center, Pulmonary and Critical Care Medicine, Nashville, Tennessee, USA
| | - Kristian Prydz
- Department of Biosciences, University of Oslo, Oslo, Norway
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15
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Santana-Molina C, Gutierrez F, Devos DP. Homology and Modular Evolution of CATCHR at the Origin of the Eukaryotic Endomembrane System. Genome Biol Evol 2021; 13:6290715. [PMID: 34061181 PMCID: PMC8290106 DOI: 10.1093/gbe/evab125] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/27/2021] [Indexed: 01/02/2023] Open
Abstract
The membrane trafficking is an essential process of eukaryotic cells, as it manages vesicular trafficking toward different parts of the cell. In this process, membrane fusions between vesicles and target membranes are mediated by several factors, including the multisubunit tethering complexes. One type of multisubunit tethering complex, the complexes associated with tethering containing helical rods (CATCHR), encompasses the exocyst, COG, GARP, and DSL1 complexes. The CATCHR share similarities at sequence, structural, and protein-complex organization level although their actual relationship is still poorly understood. In this study, we have re-evaluated CATCHR at different levels, demonstrating that gene duplications followed by neofunctionalization, were key for their origin. Our results, reveals that there are specific homology relationships and parallelism within and between the CATCHR suggesting that most of these complexes are composed by modular tetramers of four different kinds of proteins, three of them having a clear common origin. The extension of CATCHR family occurred concomitantly with the protein family expansions of their molecular partners, such as small GTPases and SNAREs, among others, and likely providing functional specificity. Our results provide novel insights into the structural organization and mechanism of action of CATCHR, with implications for the evolution of the endomembrane system of eukaryotes and promoting CATCHR as ideal candidates to study the evolution of multiprotein complexes.
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Affiliation(s)
- Carlos Santana-Molina
- Centro Andaluz de Biología del Desarrollo, Consejo Superior de Investigaciones Científicas/Universidad Pablo de Olavide/Junta de Andalucía, Seville, Spain
| | - Fernando Gutierrez
- Centro Andaluz de Biología del Desarrollo, Consejo Superior de Investigaciones Científicas/Universidad Pablo de Olavide/Junta de Andalucía, Seville, Spain.,Departamento de Genética Molecular y Microbiología, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Damien P Devos
- Centro Andaluz de Biología del Desarrollo, Consejo Superior de Investigaciones Científicas/Universidad Pablo de Olavide/Junta de Andalucía, Seville, Spain
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16
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Klim J, Zielenkiewicz U, Skoneczny M, Skoneczna A, Kurlandzka A, Kaczanowski S. Genetic interaction network has a very limited impact on the evolutionary trajectories in continuous culture-grown populations of yeast. BMC Ecol Evol 2021; 21:99. [PMID: 34039270 PMCID: PMC8157726 DOI: 10.1186/s12862-021-01830-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 05/19/2021] [Indexed: 11/30/2022] Open
Abstract
Background The impact of genetic interaction networks on evolution is a fundamental issue. Previous studies have demonstrated that the topology of the network is determined by the properties of the cellular machinery. Functionally related genes frequently interact with one another, and they establish modules, e.g., modules of protein complexes and biochemical pathways. In this study, we experimentally tested the hypothesis that compensatory evolutionary modifications, such as mutations and transcriptional changes, occur frequently in genes from perturbed modules of interacting genes. Results Using Saccharomyces cerevisiae haploid deletion mutants as a model, we investigated two modules lacking COG7 or NUP133, which are evolutionarily conserved genes with many interactions. We performed laboratory evolution experiments with these strains in two genetic backgrounds (with or without additional deletion of MSH2), subjecting them to continuous culture in a non-limiting minimal medium. Next, the evolved yeast populations were characterized through whole-genome sequencing and transcriptome analyses. No obvious compensatory changes resulting from inactivation of genes already included in modules were identified. The supposedly compensatory inactivation of genes in the evolved strains was only rarely observed to be in accordance with the established fitness effect of the genetic interaction network. In fact, a substantial majority of the gene inactivations were predicted to be neutral in the experimental conditions used to determine the interaction network. Similarly, transcriptome changes during continuous culture mostly signified adaptation to growth conditions rather than compensation of the absence of the COG7, NUP133 or MSH2 genes. However, we noticed that for genes whose inactivation was deleterious an upregulation of transcription was more common than downregulation. Conclusions Our findings demonstrate that the genetic interactions and the modular structure of the network described by others have very limited effects on the evolutionary trajectory following gene deletion of module elements in our experimental conditions and has no significant impact on short-term compensatory evolution. However, we observed likely compensatory evolution in functionally related (albeit non-interacting) genes. Supplementary Information The online version contains supplementary material available at 10.1186/s12862-021-01830-9.
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Affiliation(s)
- Joanna Klim
- Department of Microbial Biochemistry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106, Warsaw, Poland
| | - Urszula Zielenkiewicz
- Department of Microbial Biochemistry, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106, Warsaw, Poland
| | - Marek Skoneczny
- Department of Genetics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106, Warsaw, Poland
| | - Adrianna Skoneczna
- Laboratory of Mutagenesis and DNA Repair, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106, Warsaw, Poland
| | - Anna Kurlandzka
- Department of Genetics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106, Warsaw, Poland
| | - Szymon Kaczanowski
- Department of Bioinformatics, Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawińskiego 5a, 02-106, Warsaw, Poland.
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17
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Rizzo R, Russo D, Kurokawa K, Sahu P, Lombardi B, Supino D, Zhukovsky MA, Vocat A, Pothukuchi P, Kunnathully V, Capolupo L, Boncompain G, Vitagliano C, Zito Marino F, Aquino G, Montariello D, Henklein P, Mandrich L, Botti G, Clausen H, Mandel U, Yamaji T, Hanada K, Budillon A, Perez F, Parashuraman S, Hannun YA, Nakano A, Corda D, D'Angelo G, Luini A. Golgi maturation-dependent glycoenzyme recycling controls glycosphingolipid biosynthesis and cell growth via GOLPH3. EMBO J 2021; 40:e107238. [PMID: 33749896 DOI: 10.15252/embj.2020107238] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 01/24/2021] [Accepted: 02/10/2021] [Indexed: 01/08/2023] Open
Abstract
Glycosphingolipids are important components of the plasma membrane where they modulate the activities of membrane proteins including signalling receptors. Glycosphingolipid synthesis relies on competing reactions catalysed by Golgi-resident enzymes during the passage of substrates through the Golgi cisternae. The glycosphingolipid metabolic output is determined by the position and levels of the enzymes within the Golgi stack, but the mechanisms that coordinate the intra-Golgi localisation of the enzymes are poorly understood. Here, we show that a group of sequentially-acting enzymes operating at the branchpoint among glycosphingolipid synthetic pathways binds the Golgi-localised oncoprotein GOLPH3. GOLPH3 sorts these enzymes into vesicles for intra-Golgi retro-transport, acting as a component of the cisternal maturation mechanism. Through these effects, GOLPH3 controls the sub-Golgi localisation and the lysosomal degradation rate of specific enzymes. Increased GOLPH3 levels, as those observed in tumours, alter glycosphingolipid synthesis and plasma membrane composition thereby promoting mitogenic signalling and cell proliferation. These data have medical implications as they outline a novel oncogenic mechanism of action for GOLPH3 based on glycosphingolipid metabolism.
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Affiliation(s)
- Riccardo Rizzo
- Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy.,Institute of Nanotechnology, National Research Council (CNR-NANOTEC), Lecce, Italy
| | - Domenico Russo
- Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | - Kazuo Kurokawa
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, Saitama, Japan
| | - Pranoy Sahu
- Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | - Bernadette Lombardi
- Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | - Domenico Supino
- Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | - Mikhail A Zhukovsky
- Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | - Anthony Vocat
- École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Prathyush Pothukuchi
- Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | - Vidya Kunnathully
- Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | - Laura Capolupo
- École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | | | - Carlo Vitagliano
- Istituto Nazionale Tumori Fondazione G. Pascale-IRCCS, Naples, Italy
| | | | - Gabriella Aquino
- Istituto Nazionale Tumori Fondazione G. Pascale-IRCCS, Naples, Italy
| | - Daniela Montariello
- Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | - Petra Henklein
- Humboldt-Universität zu Berlin, and Berlin Institute of Health, Institute of Biochemistry, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Berlin, Germany
| | - Luigi Mandrich
- Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | - Gerardo Botti
- Istituto Nazionale Tumori Fondazione G. Pascale-IRCCS, Naples, Italy
| | - Henrik Clausen
- Faculty of Health Sciences, Centre for Glycomics, Department of Cellular and Molecular Medicine Nørre Alle 20, University of Copenhagen, Copenhagen N, Denmark
| | - Ulla Mandel
- Faculty of Health Sciences, Centre for Glycomics, Department of Cellular and Molecular Medicine Nørre Alle 20, University of Copenhagen, Copenhagen N, Denmark
| | - Toshiyuki Yamaji
- Department of Biochemistry & Cell Biology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Kentaro Hanada
- Department of Biochemistry & Cell Biology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Alfredo Budillon
- Istituto Nazionale Tumori Fondazione G. Pascale-IRCCS, Naples, Italy
| | - Franck Perez
- Institute Curie - CNRS UMR1 44, Research Center, Paris, France
| | | | - Yusuf A Hannun
- Stony Brook University Medical Center, New York, NY, USA
| | - Akihiko Nakano
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, Saitama, Japan
| | - Daniela Corda
- Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | - Giovanni D'Angelo
- Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy.,École Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Alberto Luini
- Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
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18
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Liu J, Huang Y, Li T, Jiang Z, Zeng L, Hu Z. The role of the Golgi apparatus in disease (Review). Int J Mol Med 2021; 47:38. [PMID: 33537825 PMCID: PMC7891830 DOI: 10.3892/ijmm.2021.4871] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Accepted: 01/15/2021] [Indexed: 02/07/2023] Open
Abstract
The Golgi apparatus is known to underpin many important cellular homeostatic functions, including trafficking, sorting and modifications of proteins or lipids. These functions are dysregulated in neurodegenerative diseases, cancer, infectious diseases and cardiovascular diseases, and the number of disease-related genes associated with Golgi apparatus is on the increase. Recently, many studies have suggested that the mutations in the genes encoding Golgi resident proteins can trigger the occurrence of diseases. By summarizing the pathogenesis of these genetic diseases, it was found that most of these diseases have defects in membrane trafficking. Such defects typically result in mislocalization of proteins, impaired glycosylation of proteins, and the accumulation of undegraded proteins. In the present review, we aim to understand the patterns of mutations in the genes encoding Golgi resident proteins and decipher the interplay between Golgi resident proteins and membrane trafficking pathway in cells. Furthermore, the detection of Golgi resident protein in human serum samples has the potential to be used as a diagnostic tool for diseases, and its central role in membrane trafficking pathways provides possible targets for disease therapy. Thus, we also introduced the clinical value of Golgi apparatus in the present review.
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Affiliation(s)
- Jianyang Liu
- Department of Neurology, Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, P.R. China
| | - Yan Huang
- Department of Neurology, Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, P.R. China
| | - Ting Li
- Department of Neurology, Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, P.R. China
| | - Zheng Jiang
- Department of Neurology, Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, P.R. China
| | - Liuwang Zeng
- Department of Neurology, Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, P.R. China
| | - Zhiping Hu
- Department of Neurology, Second Xiangya Hospital, Central South University, Changsha, Hunan 410011, P.R. China
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19
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The Close Relationship between the Golgi Trafficking Machinery and Protein Glycosylation. Cells 2020; 9:cells9122652. [PMID: 33321764 PMCID: PMC7764369 DOI: 10.3390/cells9122652] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2020] [Revised: 12/04/2020] [Accepted: 12/07/2020] [Indexed: 12/12/2022] Open
Abstract
Glycosylation is the most common post-translational modification of proteins; it mediates their correct folding and stability, as well as their transport through the secretory transport. Changes in N- and O-linked glycans have been associated with multiple pathological conditions including congenital disorders of glycosylation, inflammatory diseases and cancer. Glycoprotein glycosylation at the Golgi involves the coordinated action of hundreds of glycosyltransferases and glycosidases, which are maintained at the correct location through retrograde vesicle trafficking between Golgi cisternae. In this review, we describe the molecular machinery involved in vesicle trafficking and tethering at the Golgi apparatus and the effects of mutations in the context of glycan biosynthesis and human diseases.
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20
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Genome-Wide CRISPR-Cas9 Screen Reveals the Importance of the Heparan Sulfate Pathway and the Conserved Oligomeric Golgi Complex for Synthetic Double-Stranded RNA Uptake and Sindbis Virus Infection. mSphere 2020; 5:5/6/e00914-20. [PMID: 33177215 PMCID: PMC7657590 DOI: 10.1128/msphere.00914-20] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
When facing a viral infection, the organism has to put in place a number of defense mechanisms in order to clear the pathogen from the cell. At the early phase of this preparation for fighting against the invader, the innate immune response is triggered by the sensing of danger signals. Among those molecular cues, double-stranded RNA (dsRNA) is a very potent inducer of different reactions at the cellular level that can ultimately lead to cell death. Using a genome-wide screening approach, we set to identify genes involved in dsRNA entry, sensing, and apoptosis induction in human cells. This allowed us to determine that the heparan sulfate pathway and the conserved oligomeric Golgi complex are key determinants allowing entry of both dsRNA and viral nucleic acid leading to cell death. Double-stranded RNA (dsRNA) is the hallmark of many viral infections. dsRNA is produced either by RNA viruses during replication or by DNA viruses upon convergent transcription. Synthetic dsRNA is also able to mimic viral-induced activation of innate immune response and cell death. In this study, we employed a genome-wide CRISPR-Cas9 loss-of-function screen based on cell survival in order to identify genes implicated in the host response to dsRNA. By challenging HCT116 human cells with either synthetic dsRNA or Sindbis virus (SINV), we identified the heparan sulfate (HS) pathway as a crucial factor for dsRNA entry, and we validated SINV dependency on HS. Interestingly, we uncovered a novel role for COG4, a component of the conserved oligomeric Golgi (COG) complex, as a factor involved in cell survival to both dsRNA and SINV in human cells. We showed that COG4 knockout led to a decrease of extracellular HS that specifically affected dsRNA transfection efficiency and reduced viral production, which explains the increased cell survival of these mutants. IMPORTANCE When facing a viral infection, the organism has to put in place a number of defense mechanisms in order to clear the pathogen from the cell. At the early phase of this preparation for fighting against the invader, the innate immune response is triggered by the sensing of danger signals. Among those molecular cues, double-stranded RNA (dsRNA) is a very potent inducer of different reactions at the cellular level that can ultimately lead to cell death. Using a genome-wide screening approach, we set to identify genes involved in dsRNA entry, sensing, and apoptosis induction in human cells. This allowed us to determine that the heparan sulfate pathway and the conserved oligomeric Golgi complex are key determinants allowing entry of both dsRNA and viral nucleic acid leading to cell death.
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21
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D'Souza Z, Taher FS, Lupashin VV. Golgi inCOGnito: From vesicle tethering to human disease. Biochim Biophys Acta Gen Subj 2020; 1864:129694. [PMID: 32730773 PMCID: PMC7384418 DOI: 10.1016/j.bbagen.2020.129694] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/21/2020] [Accepted: 07/23/2020] [Indexed: 12/11/2022]
Abstract
The Conserved Oligomeric Golgi (COG) complex, a multi-subunit vesicle tethering complex of the CATCHR (Complexes Associated with Tethering Containing Helical Rods) family, controls several aspects of cellular homeostasis by orchestrating retrograde vesicle traffic within the Golgi. The COG complex interacts with all key players regulating intra-Golgi trafficking, namely SNAREs, SNARE-interacting proteins, Rabs, coiled-coil tethers, and vesicular coats. In cells, COG deficiencies result in the accumulation of non-tethered COG-complex dependent (CCD) vesicles, dramatic morphological and functional abnormalities of the Golgi and endosomes, severe defects in N- and O- glycosylation, Golgi retrograde trafficking, sorting and protein secretion. In humans, COG mutations lead to severe multi-systemic diseases known as COG-Congenital Disorders of Glycosylation (COG-CDG). In this report, we review the current knowledge of the COG complex and analyze COG-related trafficking and glycosylation defects in COG-CDG patients.
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Affiliation(s)
- Zinia D'Souza
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Farhana S Taher
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Vladimir V Lupashin
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
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22
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Abstract
La glycosylation est un processus cellulaire complexe conduisant à des transferts successifs de monosaccharides sur une molécule acceptrice, le plus souvent une protéine ou un lipide. Ce processus est universel chez tous les organismes vivants et est très conservé au cours de l’évolution. Chez l’homme, des perturbations survenant au cours d’une ou plusieurs réactions de glycosylation sont à l’origine de glycopathologies génétiques rares, appelées anomalies congénitales de la glycosylation ou congenital disorders of glycosylation (CDG). Cette revue propose de revisiter ces CDG, de 1980 à aujourd’hui, en présentant leurs découvertes, leurs diagnostics, leurs causes biochimiques et les traitements actuellement disponibles.
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23
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Modeling Glycan Processing Reveals Golgi-Enzyme Homeostasis upon Trafficking Defects and Cellular Differentiation. Cell Rep 2020; 27:1231-1243.e6. [PMID: 31018136 PMCID: PMC6486481 DOI: 10.1016/j.celrep.2019.03.107] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 01/24/2019] [Accepted: 03/27/2019] [Indexed: 01/11/2023] Open
Abstract
The decoration of proteins by carbohydrates is essential for eukaryotic life yet heterogeneous due to a lack of biosynthetic templates. This complex carbohydrate mixture—the glycan profile—is generated in the compartmentalized Golgi, in which level and localization of glycosylation enzymes are key determinants. Here, we develop and validate a computational model for glycan biosynthesis to probe how the biosynthetic machinery creates different glycan profiles. We combined stochastic modeling with Bayesian fitting that enables rigorous comparison to experimental data despite starting with uncertain initial parameters. This is an important development in the field of glycan modeling, which revealed biological insights about the glycosylation machinery in altered cellular states. We experimentally validated changes in N-linked glycan-modifying enzymes in cells with perturbed intra-Golgi-enzyme sorting and the predicted glycan-branching activity during osteogenesis. Our model can provide detailed information on altered biosynthetic paths, with potential for advancing treatments for glycosylation-related diseases and glyco-engineering of cells. Developed a stochastic model of N-glycosylation coupled with Bayesian fitting Validated predicted changes of Golgi organization in trafficking mutants Model pinpointed functionally relevant glycan alterations in osteogenesis
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24
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Smith EP, Cotto-Rosario A, Borghesan E, Held K, Miller CN, Celli J. Epistatic Interplay between Type IV Secretion Effectors Engages the Small GTPase Rab2 in the Brucella Intracellular Cycle. mBio 2020; 11:e03350-19. [PMID: 32234817 PMCID: PMC7157780 DOI: 10.1128/mbio.03350-19] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 03/06/2020] [Indexed: 11/20/2022] Open
Abstract
Intracellular bacterial pathogens remodel cellular functions during their infectious cycle via the coordinated actions of effector molecules delivered through dedicated secretion systems. While the function of many individual effectors is known, how they interact to promote pathogenesis is rarely understood. The zoonotic bacterium Brucella abortus, the causative agent of brucellosis, delivers effector proteins via its VirB type IV secretion system (T4SS) which mediate biogenesis of the endoplasmic reticulum (ER)-derived replicative Brucella-containing vacuole (rBCV). Here, we show that T4SS effectors BspB and RicA display epistatic interactions in Brucella replication. Defects in rBCV biogenesis and Brucella replication caused by deletion of bspB were dependent on the host GTPase Rab2a and suppressed by the deletion of ricA, indicating a role of Rab2-binding effector RicA in these phenotypic defects. Rab2a requirements for rBCV biogenesis and Brucella intracellular replication were abolished upon deletion of both bspB and ricA, demonstrating that the functional interaction of these effectors engages Rab2-dependent transport in the Brucella intracellular cycle. Expression of RicA impaired host secretion and caused Golgi fragmentation. While BspB-mediated changes in ER-to-Golgi transport were independent of RicA and Rab2a, BspB-driven alterations in Golgi vesicular traffic also involved RicA and Rab2a, defining BspB and RicA's functional interplay at the Golgi interface. Altogether, these findings support a model where RicA modulation of Rab2a functions impairs Brucella replication but is compensated by BspB-mediated remodeling of Golgi apparatus-associated vesicular transport, revealing an epistatic interaction between these T4SS effectors.IMPORTANCE Bacterial pathogens with an intracellular lifestyle modulate many host cellular processes to promote their infectious cycle. They do so by delivering effector proteins into host cells via dedicated secretion systems that target specific host functions. While the roles of many individual effectors are known, how their modes of action are coordinated is rarely understood. Here, we show that the zoonotic bacterium Brucella abortus delivers the BspB effector that mitigates the negative effect on bacterial replication that the RicA effector exerts via modulation of the host small GTPase Rab2. These findings provide an example of functional integration between bacterial effectors that promotes proliferation of pathogens.
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Affiliation(s)
- Erin P Smith
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, Washington, USA
| | - Alexis Cotto-Rosario
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, Washington, USA
| | - Elizabeth Borghesan
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, Washington, USA
| | - Kiara Held
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, Washington, USA
| | - Cheryl N Miller
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, Washington, USA
| | - Jean Celli
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, Washington, USA
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25
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Defining the clinical phenotype of Saul-Wilson syndrome. Genet Med 2020; 22:857-866. [PMID: 31949312 PMCID: PMC7205587 DOI: 10.1038/s41436-019-0737-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 12/16/2019] [Accepted: 12/17/2019] [Indexed: 11/29/2022] Open
Abstract
Purpose: Four patients with Saul-Wilson syndrome were reported between 1982 and 1994, but no additional individuals were described until 2018, when the molecular etiology of the disease was elucidated. Hence, the clinical phenotype of the disease remains poorly defined. We address this shortcoming by providing a detailed characterization of its phenotype. Methods: Retrospective chart reviews were performed and primary radiographs assessed for all 14 individuals. Four individuals underwent detailed ophthalmologic examination by the same physician. Two individuals underwent gynecologic evaluation. Z-scores for height, weight, head circumference and BMI were calculated at different ages. Results: All patients exhibited short stature, with sharp decline from the mean within the first months of life, and a final height Z-score between −4 and −8.5 standard deviations. The facial and radiographic features evolved over time. Intermittent neutropenia was frequently observed. Novel findings included elevation of liver transaminases, skeletal fragility, rod-cone dystrophy, and cystic macular changes. Conclusion: Saul-Wilson syndrome presents a remarkably uniform phenotype, and the comprehensive description of our cohort allows for improved understanding of the long-term morbidity of the condition, establishment of follow-up recommendations for affected individuals, and documentation of the natural history into adulthood for comparison with treated patients, when therapeutics become available.
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Lawaju BR, Niraula P, Lawrence GW, Lawrence KS, Klink VP. The Glycine max Conserved Oligomeric Golgi (COG) Complex Functions During a Defense Response to Heterodera glycines. FRONTIERS IN PLANT SCIENCE 2020; 11:564495. [PMID: 33262774 PMCID: PMC7686354 DOI: 10.3389/fpls.2020.564495] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 10/02/2020] [Indexed: 05/07/2023]
Abstract
The conserved oligomeric Golgi (COG) complex, functioning in retrograde trafficking, is a universal structure present among eukaryotes that maintains the correct Golgi structure and function. The COG complex is composed of eight subunits coalescing into two sub-complexes. COGs1-4 compose Sub-complex A. COGs5-8 compose Sub-complex B. The observation that COG interacts with the syntaxins, suppressors of the erd2-deletion 5 (Sed5p), is noteworthy because Sed5p also interacts with Sec17p [alpha soluble NSF attachment protein (α-SNAP)]. The α-SNAP gene is located within the major Heterodera glycines [soybean cyst nematode (SCN)] resistance locus (rhg1) and functions in resistance. The study presented here provides a functional analysis of the Glycine max COG complex. The analysis has identified two paralogs of each COG gene. Functional transgenic studies demonstrate at least one paralog of each COG gene family functions in G. max during H. glycines resistance. Furthermore, treatment of G. max with the bacterial effector harpin, known to function in effector triggered immunity (ETI), leads to the induced transcription of at least one member of each COG gene family that has a role in H. glycines resistance. In some instances, altered COG gene expression changes the relative transcript abundance of syntaxin 31. These results indicate that the G. max COG complex functions through processes involving ETI leading to H. glycines resistance.
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Affiliation(s)
- Bisho Ram Lawaju
- Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, Starkville, MS, United States
| | - Prakash Niraula
- Department of Biological Sciences, Mississippi State University, Starkville, MS, United States
| | - Gary W. Lawrence
- Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, Starkville, MS, United States
| | - Kathy S. Lawrence
- Department of Entomology and Plant Pathology, Auburn University, Auburn, AL, United States
| | - Vincent P. Klink
- Department of Biochemistry, Molecular Biology, Entomology and Plant Pathology, Mississippi State University, Starkville, MS, United States
- Department of Biological Sciences, Mississippi State University, Starkville, MS, United States
- Center for Computational Sciences High Performance Computing Collaboratory, Mississippi State University, Starkville, MS, United States
- *Correspondence: Vincent P. Klink, ;
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Cruz MD, Kim K. The inner workings of intracellular heterotypic and homotypic membrane fusion mechanisms. J Biosci 2019; 44:91. [PMID: 31502569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Intracellular trafficking is a field that has been intensively studied for years and yet there remains much to be learned. Part of the reason that there is so much obscurity remaining in this field is due to all the pathways and the stages that define cellular trafficking. One of the major steps in cellular trafficking is fusion. Fusion is defined as the terminal step that occurs when a cargo-laden vesicle arrives at the proper destination. There are two types of fusion within a cell: homotypic and heterotypic fusion. Homotypic fusion occurs when the two membranes merging together are of the same type such as vacuole to vacuole fusion. Heterotypic fusion occurs when the two membranes at play are of different types such as when an endosomal membrane fuses with a Golgi membrane. In this review, we will focus on all the protein components - Rabs, Golgins, Multisubunit tethers, GTPases, protein phosphatases and SNAREs - that have been known to function in both of these types of fusion. We hope to develop a model of how all of these constituents function together to achieve membrane fusion. Membrane fusion is a biological process absolutely necessary for proper intracellular trafficking. Due to the degree of importance multiple proteins are required for it to be properly carried through. Whether we are talking about heterotypic or homotypic fusion, any defects in the fusion machinery can result in disease states such as Parkinson's and Alzheimer's disease. Although much research has significantly expanded our knowledge of fusion, there is still much more to be learned.
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Blackburn JB, D'Souza Z, Lupashin VV. Maintaining order: COG complex controls Golgi trafficking, processing, and sorting. FEBS Lett 2019; 593:2466-2487. [PMID: 31381138 PMCID: PMC6771879 DOI: 10.1002/1873-3468.13570] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 07/31/2019] [Accepted: 08/01/2019] [Indexed: 12/31/2022]
Abstract
The conserved oligomeric Golgi (COG) complex, a multisubunit tethering complex of the CATCHR (complexes associated with tethering containing helical rods) family, controls membrane trafficking and ensures Golgi homeostasis by orchestrating retrograde vesicle targeting within the Golgi. In humans, COG defects lead to severe multisystemic diseases known as COG‐congenital disorders of glycosylation (COG‐CDG). The COG complex both physically and functionally interacts with all classes of molecules maintaining intra‐Golgi trafficking, namely SNAREs, SNARE‐interacting proteins, Rabs, coiled‐coil tethers, and vesicular coats. Here, we review our current knowledge of COG‐related trafficking and glycosylation defects in humans and model organisms, and analyze possible scenarios for the molecular mechanism of the COG orchestrated vesicle targeting.
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Affiliation(s)
- Jessica B Blackburn
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Zinia D'Souza
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Vladimir V Lupashin
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, AR, USA
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Pantazopoulou A, Glick BS. A Kinetic View of Membrane Traffic Pathways Can Transcend the Classical View of Golgi Compartments. Front Cell Dev Biol 2019; 7:153. [PMID: 31448274 PMCID: PMC6691344 DOI: 10.3389/fcell.2019.00153] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 07/22/2019] [Indexed: 01/07/2023] Open
Abstract
A long-standing assumption is that the cisternae of the Golgi apparatus can be grouped into functionally distinct compartments, yet the molecular identities of those compartments have not been clearly described. The concept of a compartmentalized Golgi is challenged by the cisternal maturation model, which postulates that cisternae form de novo and then undergo progressive biochemical changes. Cisternal maturation can potentially be reconciled with Golgi compartmentation by defining compartments as discrete kinetic stages in the maturation process. These kinetic stages are distinguished by the traffic pathways that are operating. For example, a major transition occurs when a cisterna stops producing COPI vesicles and begins producing clathrin-coated vesicles. This transition separates one kinetic stage, the "early Golgi," from a subsequent kinetic stage, the "late Golgi" or "trans-Golgi network (TGN)." But multiple traffic pathways drive Golgi maturation, and the periods of operation for different traffic pathways can partially overlap, so there is no simple way to define a full set of Golgi compartments in terms of kinetic stages. Instead, we propose that the focus should be on the series of transitions experienced by a Golgi cisterna as various traffic pathways are switched on and off. These traffic pathways drive changes in resident transmembrane protein composition. Transitions in traffic pathways seem to be the fundamental, conserved determinants of Golgi organization. According to this view, the initial goal is to identify the relevant traffic pathways and place them on the kinetic map of Golgi maturation, and the ultimate goal is to elucidate the logic circuit that switches individual traffic pathways on and off as a cisterna matures.
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Affiliation(s)
- Areti Pantazopoulou
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL, United States
| | - Benjamin S Glick
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL, United States
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30
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Delgado Cruz M, Kim K. The inner workings of intracellular heterotypic and homotypic membrane fusion mechanisms. J Biosci 2019. [DOI: 10.1007/s12038-019-9913-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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31
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Linders PT, Horst CVD, Beest MT, van den Bogaart G. Stx5-Mediated ER-Golgi Transport in Mammals and Yeast. Cells 2019; 8:cells8080780. [PMID: 31357511 PMCID: PMC6721632 DOI: 10.3390/cells8080780] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2019] [Revised: 07/25/2019] [Accepted: 07/25/2019] [Indexed: 01/12/2023] Open
Abstract
The soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) syntaxin 5 (Stx5) in mammals and its ortholog Sed5p in Saccharomyces cerevisiae mediate anterograde and retrograde endoplasmic reticulum (ER)-Golgi trafficking. Stx5 and Sed5p are structurally highly conserved and are both regulated by interactions with other ER-Golgi SNARE proteins, the Sec1/Munc18-like protein Scfd1/Sly1p and the membrane tethering complexes COG, p115, and GM130. Despite these similarities, yeast Sed5p and mammalian Stx5 are differently recruited to COPII-coated vesicles, and Stx5 interacts with the microtubular cytoskeleton, whereas Sed5p does not. In this review, we argue that these different Stx5 interactions contribute to structural differences in ER-Golgi transport between mammalian and yeast cells. Insight into the function of Stx5 is important given its essential role in the secretory pathway of eukaryotic cells and its involvement in infections and neurodegenerative diseases.
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Affiliation(s)
- Peter Ta Linders
- Tumor Immunology Lab, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Geert Grooteplein 28, 6525 GA Nijmegen, The Netherlands
| | - Chiel van der Horst
- Tumor Immunology Lab, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Geert Grooteplein 28, 6525 GA Nijmegen, The Netherlands
| | - Martin Ter Beest
- Tumor Immunology Lab, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Geert Grooteplein 28, 6525 GA Nijmegen, The Netherlands
| | - Geert van den Bogaart
- Tumor Immunology Lab, Radboud University Medical Center, Radboud Institute for Molecular Life Sciences, Geert Grooteplein 28, 6525 GA Nijmegen, The Netherlands.
- Department of Molecular Immunology, Groningen Biomolecular Sciences and Biotechnology Institute, University of Groningen, Nijenborgh 7, 9747 AG Groningen, The Netherlands.
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D'Souza Z, Blackburn JB, Kudlyk T, Pokrovskaya ID, Lupashin VV. Defects in COG-Mediated Golgi Trafficking Alter Endo-Lysosomal System in Human Cells. Front Cell Dev Biol 2019; 7:118. [PMID: 31334232 PMCID: PMC6616090 DOI: 10.3389/fcell.2019.00118] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Accepted: 06/11/2019] [Indexed: 12/27/2022] Open
Abstract
The conserved oligomeric complex (COG) is a multi-subunit vesicle tethering complex that functions in retrograde trafficking at the Golgi. We have previously demonstrated that the formation of enlarged endo-lysosomal structures (EELSs) is one of the major glycosylation-independent phenotypes of cells depleted for individual COG complex subunits. Here, we characterize the EELSs in HEK293T cells using microscopy and biochemical approaches. Our analysis revealed that the EELSs are highly acidic and that vATPase-dependent acidification is essential for the maintenance of this enlarged compartment. The EELSs are accessible to both trans-Golgi enzymes and endocytic cargo. Moreover, the EELSs specifically accumulate endolysosomal proteins Lamp2, CD63, Rab7, Rab9, Rab39, Vamp7, and STX8 on their surface. The EELSs are distinct from lysosomes and do not accumulate active Cathepsin B. Retention using selective hooks (RUSH) experiments revealed that biosynthetic cargo mCherry-Lamp1 reaches the EELSs much faster as compared to both receptor-mediated and soluble endocytic cargo, indicating TGN origin of the EELSs. In support to this hypothesis, EELSs are enriched with TGN specific lipid PI4P. Additionally, analysis of COG4/VPS54 double KO cells revealed that the activity of the GARP tethering complex is necessary for EELSs’ accumulation, indicating that protein mistargeting and the imbalance of Golgi-endosome membrane flow leads to the formation of EELSs in COG-deficient cells. The EELSs are likely to serve as a degradative storage hybrid organelle for mistargeted Golgi enzymes and underglycosylated glycoconjugates. To our knowledge this is the first report of the formation of an enlarged hybrid endosomal compartment in a response to malfunction of the intra-Golgi trafficking machinery.
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Affiliation(s)
- Zinia D'Souza
- Department of Physiology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Jessica Bailey Blackburn
- Department of Physiology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Tetyana Kudlyk
- Department of Physiology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Irina D Pokrovskaya
- Department of Physiology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Vladimir V Lupashin
- Department of Physiology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
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33
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Lowe M. The Physiological Functions of the Golgin Vesicle Tethering Proteins. Front Cell Dev Biol 2019; 7:94. [PMID: 31316978 PMCID: PMC6611411 DOI: 10.3389/fcell.2019.00094] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 05/16/2019] [Indexed: 01/02/2023] Open
Abstract
The golgins comprise a family of vesicle tethering proteins that act in a selective manner to tether transport vesicles at the Golgi apparatus. Tethering is followed by membrane fusion to complete the delivery of vesicle-bound cargo to the Golgi. Different golgins are localized to different regions of the Golgi, and their ability to selectively tether transport vesicles is important for the specificity of vesicle traffic in the secretory pathway. In recent years, our mechanistic understanding of golgin-mediated tethering has greatly improved. We are also beginning to appreciate how the loss of golgin function can impact upon physiological processes through the use of animal models and the study of human disease. These approaches have revealed that loss of a golgin causes tissue-restricted phenotypes, which can vary in severity and the cell types affected. In many cases, it is possible to attribute these phenotypes to a defect in vesicular traffic, although why certain tissues are sensitive to loss of a particular golgin is still, in most cases, unclear. Here, I will summarize recent progress in our understanding of golgins, focusing on the physiological roles of these proteins, as determined from animal models and the study of disease in humans. I will describe what these in vivo analyses have taught us, as well as highlight less understood aspects, and areas for future investigations.
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Affiliation(s)
- Martin Lowe
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
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34
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Ungermann C, Kümmel D. Structure of membrane tethers and their role in fusion. Traffic 2019; 20:479-490. [DOI: 10.1111/tra.12655] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 04/26/2019] [Accepted: 05/03/2019] [Indexed: 12/27/2022]
Affiliation(s)
- Christian Ungermann
- Biochemistry Section, Department of Biology/ChemistryUniversity of Osnabrück Osnabrück Germany
- Center for Cellular Nanoanalytics (CellNanOs)University of Osnabrück Osnabrück Germany
| | - Daniel Kümmel
- Biochemistry & Structural Biology Section, Institute of BiochemistryUniversity of Münster Münster Germany
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35
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Abstract
Bacteria of the genus Brucella colonize a wide variety of mammalian hosts, in which their infectious cycle and ability to cause disease predominantly rely on an intracellular lifestyle within phagocytes. Upon entry into host cells, Brucella organisms undergo a complex, multistage intracellular cycle in which they sequentially traffic through, and exploit functions of, the endocytic, secretory, and autophagic compartments via type IV secretion system (T4SS)-mediated delivery of bacterial effectors. These effectors modulate an array of host functions and machineries to first promote conversion of the initial endosome-like Brucella-containing vacuole (eBCV) into a replication-permissive organelle derived from the host endoplasmic reticulum (rBCV) and then to an autophagy-related vacuole (aBCV) that mediates bacterial egress. Here we detail and discuss our current knowledge of cellular and molecular events of the Brucella intracellular cycle. We discuss the importance of the endosomal stage in determining T4SS competency, the roles of autophagy in rBCV biogenesis and aBCV formation, and T4SS-driven mechanisms of modulation of host secretory traffic in rBCV biogenesis and bacterial egress.
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36
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Chang SJ, Jin SC, Jiao X, Galán JE. Unique features in the intracellular transport of typhoid toxin revealed by a genome-wide screen. PLoS Pathog 2019; 15:e1007704. [PMID: 30951565 PMCID: PMC6469816 DOI: 10.1371/journal.ppat.1007704] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 04/17/2019] [Accepted: 03/13/2019] [Indexed: 12/29/2022] Open
Abstract
Typhoid toxin is a virulence factor for Salmonella Typhi and Paratyphi, the cause of typhoid fever in humans. This toxin has a unique architecture in that its pentameric B subunit, made of PltB, is linked to two enzymatic A subunits, the ADP ribosyl transferase PltA and the deoxyribonuclease CdtB. Typhoid toxin is uniquely adapted to humans, recognizing surface glycoprotein sialoglycans terminated in acetyl neuraminic acid, which are preferentially expressed by human cells. The transport pathway to its cellular targets followed by typhoid toxin after receptor binding is currently unknown. Through a genome-wide CRISPR/Cas9-mediated screen we have characterized the mechanisms by which typhoid toxin is transported within human cells. We found that typhoid toxin hijacks specific elements of the retrograde transport and endoplasmic reticulum-associated degradation machineries to reach its subcellular destination within target cells. Our study reveals unique and common features in the transport mechanisms of bacterial toxins that could serve as the bases for the development of novel anti-toxin therapeutic strategies.
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Affiliation(s)
- Shu-Jung Chang
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Sheng Chih Jin
- Department of Genetics, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Xuyao Jiao
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, Connecticut, United States of America
| | - Jorge E Galán
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, Connecticut, United States of America
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37
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Witkos TM, Chan WL, Joensuu M, Rhiel M, Pallister E, Thomas-Oates J, Mould AP, Mironov AA, Biot C, Guerardel Y, Morelle W, Ungar D, Wieland FT, Jokitalo E, Tassabehji M, Kornak U, Lowe M. GORAB scaffolds COPI at the trans-Golgi for efficient enzyme recycling and correct protein glycosylation. Nat Commun 2019; 10:127. [PMID: 30631079 PMCID: PMC6328613 DOI: 10.1038/s41467-018-08044-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 12/06/2018] [Indexed: 01/08/2023] Open
Abstract
COPI is a key mediator of protein trafficking within the secretory pathway. COPI is recruited to the membrane primarily through binding to Arf GTPases, upon which it undergoes assembly to form coated transport intermediates responsible for trafficking numerous proteins, including Golgi-resident enzymes. Here, we identify GORAB, the protein mutated in the skin and bone disorder gerodermia osteodysplastica, as a component of the COPI machinery. GORAB forms stable domains at the trans-Golgi that, via interactions with the COPI-binding protein Scyl1, promote COPI recruitment to these domains. Pathogenic GORAB mutations perturb Scyl1 binding or GORAB assembly into domains, indicating the importance of these interactions. Loss of GORAB causes impairment of COPI-mediated retrieval of trans-Golgi enzymes, resulting in a deficit in glycosylation of secretory cargo proteins. Our results therefore identify GORAB as a COPI scaffolding factor, and support the view that defective protein glycosylation is a major disease mechanism in gerodermia osteodysplastica.
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Affiliation(s)
- Tomasz M Witkos
- School of Biology, Faculty of Biology, Medicine and Health, University of Manchester, The Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
| | - Wing Lee Chan
- Berlin-Brandenburg Centre for Regenerative Therapies (BCRT), Institut fuer Medizinische Genetik und Humangenetik, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, 13353, Germany
- FG Development & Disease, Max Planck Institut fuer Molekulare Genetik, Berlin, 14195, Germany
| | - Merja Joensuu
- Cell and Molecular Biology Program, Institute of Biotechnology, University of Helsinki, Helsinki, 00014, Finland
- Clem Jones Centre of Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, Brisbane, QLD 4072, Australia
- Minerva Foundation Institute for Medical Research, 00290, Helsinki, Finland
| | - Manuel Rhiel
- Heidelberg University Biochemistry Center, Heidelberg University, Heidelberg, 69120, Germany
| | - Ed Pallister
- Department of Chemistry, University of York, York, YO10 5DG, UK
| | | | - A Paul Mould
- School of Biology, Faculty of Biology, Medicine and Health, University of Manchester, The Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
| | - Alex A Mironov
- School of Biology, Faculty of Biology, Medicine and Health, University of Manchester, The Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
| | - Christophe Biot
- Univ. Lille, CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, F-59000, Lille, France
| | - Yann Guerardel
- Univ. Lille, CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, F-59000, Lille, France
| | - Willy Morelle
- Univ. Lille, CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, F-59000, Lille, France
| | - Daniel Ungar
- Department of Biology, University of York, York, YO10 5DD, UK
| | - Felix T Wieland
- Heidelberg University Biochemistry Center, Heidelberg University, Heidelberg, 69120, Germany
| | - Eija Jokitalo
- Cell and Molecular Biology Program, Institute of Biotechnology, University of Helsinki, Helsinki, 00014, Finland
| | - May Tassabehji
- School of Biology, Faculty of Biology, Medicine and Health, University of Manchester, The Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK
- Manchester Centre for Genomic Medicine, St. Mary's Hospital, Manchester Academic Health Sciences Centre (MAHSC), Manchester, M13 9WL, UK
| | - Uwe Kornak
- Berlin-Brandenburg Centre for Regenerative Therapies (BCRT), Institut fuer Medizinische Genetik und Humangenetik, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, 13353, Germany
- FG Development & Disease, Max Planck Institut fuer Molekulare Genetik, Berlin, 14195, Germany
| | - Martin Lowe
- School of Biology, Faculty of Biology, Medicine and Health, University of Manchester, The Michael Smith Building, Oxford Road, Manchester, M13 9PT, UK.
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Ferreira CR, Xia ZJ, Clément A, Parry DA, Davids M, Taylan F, Sharma P, Turgeon CT, Blanco-Sánchez B, Ng BG, Logan CV, Wolfe LA, Solomon BD, Cho MT, Douglas G, Carvalho DR, Bratke H, Haug MG, Phillips JB, Wegner J, Tiemeyer M, Aoki K, Nordgren A, Hammarsjö A, Duker AL, Rohena L, Hove HB, Ek J, Adams D, Tifft CJ, Onyekweli T, Weixel T, Macnamara E, Radtke K, Powis Z, Earl D, Gabriel M, Russi AHS, Brick L, Kozenko M, Tham E, Raymond KM, Phillips JA, Tiller GE, Wilson WG, Hamid R, Malicdan MC, Nishimura G, Grigelioniene G, Jackson A, Westerfield M, Bober MB, Gahl WA, Freeze HH, Gahl WA, Freeze HH. A Recurrent De Novo Heterozygous COG4 Substitution Leads to Saul-Wilson Syndrome, Disrupted Vesicular Trafficking, and Altered Proteoglycan Glycosylation. Am J Hum Genet 2018; 103:553-567. [PMID: 30290151 DOI: 10.1016/j.ajhg.2018.09.003] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Accepted: 08/31/2018] [Indexed: 12/18/2022] Open
Abstract
The conserved oligomeric Golgi (COG) complex is involved in intracellular vesicular transport, and is composed of eight subunits distributed in two lobes, lobe A (COG1-4) and lobe B (COG5-8). We describe fourteen individuals with Saul-Wilson syndrome, a rare form of primordial dwarfism with characteristic facial and radiographic features. All affected subjects harbored heterozygous de novo variants in COG4, giving rise to the same recurrent amino acid substitution (p.Gly516Arg). Affected individuals' fibroblasts, whose COG4 mRNA and protein were not decreased, exhibited delayed anterograde vesicular trafficking from the ER to the Golgi and accelerated retrograde vesicular recycling from the Golgi to the ER. This altered steady-state equilibrium led to a decrease in Golgi volume, as well as morphologic abnormalities with collapse of the Golgi stacks. Despite these abnormalities of the Golgi apparatus, protein glycosylation in sera and fibroblasts from affected subjects was not notably altered, but decorin, a proteoglycan secreted into the extracellular matrix, showed altered Golgi-dependent glycosylation. In summary, we define a specific heterozygous COG4 substitution as the molecular basis of Saul-Wilson syndrome, a rare skeletal dysplasia distinct from biallelic COG4-CDG.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - William A Gahl
- Office of the Clinical Director, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892, USA
| | - Hudson H Freeze
- Human Genetics Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
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Frappaolo A, Sechi S, Kumagai T, Karimpour-Ghahnavieh A, Tiemeyer M, Giansanti MG. Modeling Congenital Disorders of N-Linked Glycoprotein Glycosylation in Drosophila melanogaster. Front Genet 2018; 9:436. [PMID: 30333856 PMCID: PMC6176275 DOI: 10.3389/fgene.2018.00436] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 09/14/2018] [Indexed: 11/13/2022] Open
Abstract
Protein glycosylation, the enzymatic addition of N-linked or O-linked glycans to proteins, serves crucial functions in animal cells and requires the action of glycosyltransferases, glycosidases and nucleotide-sugar transporters, localized in the endoplasmic reticulum and Golgi apparatus. Congenital Disorders of Glycosylation (CDGs) comprise a family of multisystemic diseases caused by mutations in genes encoding proteins involved in glycosylation pathways. CDGs are classified into two large groups. Type I CDGs affect the synthesis of the dolichol-linked Glc3Man9GlcNac2 precursor of N-linked glycosylation or its transfer to acceptor proteins. Type II CDG (CDG-II) diseases impair either the trimming of the N-linked oligosaccharide, the addition of terminal glycans or the biosynthesis of O-linked oligosaccharides, which occur in the Golgi apparatus. So far, over 100 distinct forms of CDGs are known, with the majority of them characterized by neurological defects including mental retardation, seizures and hypotonia. Yet, it is unclear how defective glycosylation causes the pathology of CDGs. This issue can be only addressed by developing animal models of specific CDGs. Drosophila melanogaster is emerging as a highly suitable organism for analyzing glycan-dependent functions in the central nervous system (CNS) and the involvement of N-glycosylation in neuropathologies. In this review we illustrate recent work that highlights the genetic and neurobiologic advantages offered by D. melanogaster for dissecting glycosylation pathways and modeling CDG pathophysiology.
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Affiliation(s)
- Anna Frappaolo
- Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Biologia e Biotecnologie, Sapienza - Università di Roma, Rome, Italy
| | - Stefano Sechi
- Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Biologia e Biotecnologie, Sapienza - Università di Roma, Rome, Italy
| | - Tadahiro Kumagai
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States
| | - Angela Karimpour-Ghahnavieh
- Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Biologia e Biotecnologie, Sapienza - Università di Roma, Rome, Italy
| | - Michael Tiemeyer
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, United States.,Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
| | - Maria Grazia Giansanti
- Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Biologia e Biotecnologie, Sapienza - Università di Roma, Rome, Italy
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40
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Hernández‐González M, Pantazopoulou A, Spanoudakis D, Seegers CL, Peñalva MA. Genetic dissection of the secretory route followed by a fungal extracellular glycosyl hydrolase. Mol Microbiol 2018; 109:781-800. [DOI: 10.1111/mmi.14073] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2018] [Revised: 06/15/2018] [Accepted: 07/02/2018] [Indexed: 01/16/2023]
Affiliation(s)
- Miguel Hernández‐González
- Department of Cellular and Molecular Biology and WhiteBiotech Interdepartmental Unit Centro de Investigaciones Biológicas CSIC Madrid Spain
| | - Areti Pantazopoulou
- Department of Cellular and Molecular Biology and WhiteBiotech Interdepartmental Unit Centro de Investigaciones Biológicas CSIC Madrid Spain
- Department of Molecular Genetics and Cell Biology The University of Chicago Chicago IL USA
| | - Dimitris Spanoudakis
- Department of Cellular and Molecular Biology and WhiteBiotech Interdepartmental Unit Centro de Investigaciones Biológicas CSIC Madrid Spain
| | - Christel L.C. Seegers
- Department of Cellular and Molecular Biology and WhiteBiotech Interdepartmental Unit Centro de Investigaciones Biológicas CSIC Madrid Spain
- Avebe UA Foxhol The Netherlands
| | - Miguel A. Peñalva
- Department of Cellular and Molecular Biology and WhiteBiotech Interdepartmental Unit Centro de Investigaciones Biológicas CSIC Madrid Spain
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41
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Blackburn JB, Kudlyk T, Pokrovskaya I, Lupashin VV. More than just sugars: Conserved oligomeric Golgi complex deficiency causes glycosylation-independent cellular defects. Traffic 2018; 19:463-480. [PMID: 29573151 PMCID: PMC5948163 DOI: 10.1111/tra.12564] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 03/14/2018] [Accepted: 03/15/2018] [Indexed: 01/03/2023]
Abstract
The conserved oligomeric Golgi (COG) complex controls membrane trafficking and ensures Golgi homeostasis by orchestrating retrograde vesicle trafficking within the Golgi. Human COG defects lead to severe multisystemic diseases known as COG-congenital disorders of glycosylation (COG-CDG). To gain better understanding of COG-CDGs, we compared COG knockout cells with cells deficient to 2 key enzymes, Alpha-1,3-mannosyl-glycoprotein 2-beta-N-acetylglucosaminyltransferase and uridine diphosphate-glucose 4-epimerase (GALE), which contribute to proper N- and O-glycosylation. While all knockout cells share similar defects in glycosylation, these defects only account for a small fraction of observed COG knockout phenotypes. Glycosylation deficiencies were not associated with the fragmented Golgi, abnormal endolysosomes, defective sorting and secretion or delayed retrograde trafficking, indicating that these phenotypes are probably not due to hypoglycosylation, but to other specific interactions or roles of the COG complex. Importantly, these COG deficiency specific phenotypes were also apparent in COG7-CDG patient fibroblasts, proving the human disease relevance of our CRISPR knockout findings. The knowledge gained from this study has important implications, both for understanding the physiological role of COG complex in Golgi homeostasis in eukaryotic cells, and for better understanding human diseases associated with COG/Golgi impairment.
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Affiliation(s)
- Jessica B Blackburn
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Tetyana Kudlyk
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Irina Pokrovskaya
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Vladimir V Lupashin
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
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42
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Zhang X, Wang L, Lak B, Li J, Jokitalo E, Wang Y. GRASP55 Senses Glucose Deprivation through O-GlcNAcylation to Promote Autophagosome-Lysosome Fusion. Dev Cell 2018; 45:245-261.e6. [PMID: 29689198 DOI: 10.1016/j.devcel.2018.03.023] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 02/06/2018] [Accepted: 03/26/2018] [Indexed: 12/01/2022]
Abstract
The Golgi apparatus is the central hub for protein trafficking and glycosylation in the secretory pathway. However, how the Golgi responds to glucose deprivation is so far unknown. Here, we report that GRASP55, the Golgi stacking protein located in medial- and trans-Golgi cisternae, is O-GlcNAcylated by the O-GlcNAc transferase OGT under growth conditions. Glucose deprivation reduces GRASP55 O-GlcNAcylation. De-O-GlcNAcylated GRASP55 forms puncta outside of the Golgi area, which co-localize with autophagosomes and late endosomes/lysosomes. GRASP55 depletion reduces autophagic flux and results in autophagosome accumulation, while expression of an O-GlcNAcylation-deficient mutant of GRASP55 accelerates autophagic flux. Biochemically, GRASP55 interacts with LC3-II on the autophagosomes and LAMP2 on late endosomes/lysosomes and functions as a bridge between LC3-II and LAMP2 for autophagosome and lysosome fusion; this function is negatively regulated by GRASP55 O-GlcNAcylation. Therefore, GRASP55 senses glucose levels through O-GlcNAcylation and acts as a tether to facilitate autophagosome maturation.
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Affiliation(s)
- Xiaoyan Zhang
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, 830 North University Avenue, Ann Arbor, MI 48109-1048, USA.
| | - Leibin Wang
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, 830 North University Avenue, Ann Arbor, MI 48109-1048, USA
| | - Behnam Lak
- Cell and Molecular Biology Program, Institute of Biotechnology, University of Helsinki, P.O. Box 56, Viikinkaari 9, Helsinki 00014, Finland
| | - Jie Li
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, 830 North University Avenue, Ann Arbor, MI 48109-1048, USA
| | - Eija Jokitalo
- Cell and Molecular Biology Program, Institute of Biotechnology, University of Helsinki, P.O. Box 56, Viikinkaari 9, Helsinki 00014, Finland
| | - Yanzhuang Wang
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, 830 North University Avenue, Ann Arbor, MI 48109-1048, USA; Department of Neurology, University of Michigan School of Medicine, Ann Arbor, MI 48109-1048, USA.
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43
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Hernández-González M, Bravo-Plaza I, Pinar M, de los Ríos V, Arst HN, Peñalva MA. Endocytic recycling via the TGN underlies the polarized hyphal mode of life. PLoS Genet 2018; 14:e1007291. [PMID: 29608571 PMCID: PMC5880334 DOI: 10.1371/journal.pgen.1007291] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 03/06/2018] [Indexed: 12/13/2022] Open
Abstract
Intracellular traffic in Aspergillus nidulans hyphae must cope with the challenges that the high rates of apical extension (1μm/min) and the long intracellular distances (>100 μm) impose. Understanding the ways in which the hyphal tip cell coordinates traffic to meet these challenges is of basic importance, but is also of considerable applied interest, as fungal invasiveness of animals and plants depends critically upon maintaining these high rates of growth. Rapid apical extension requires localization of cell-wall-modifying enzymes to hyphal tips. By combining genetic blocks in different trafficking steps with multidimensional epifluorescence microscopy and quantitative image analyses we demonstrate that polarization of the essential chitin-synthase ChsB occurs by indirect endocytic recycling, involving delivery/exocytosis to apices followed by internalization by the sub-apical endocytic collar of actin patches and subsequent trafficking to TGN cisternae, where it accumulates for ~1 min before being re-delivered to the apex by a RAB11/TRAPPII-dependent pathway. Accordingly, ChsB is stranded at the TGN by Sec7 inactivation but re-polarizes to the apical dome if the block is bypassed by a mutation in geaAgea1 that restores growth in the absence of Sec7. That polarization is independent of RAB5, that ChsB predominates at apex-proximal cisternae, and that upon dynein impairment ChsB is stalled at the tips in an aggregated endosome indicate that endocytosed ChsB traffics to the TGN via sorting endosomes functionally located upstream of the RAB5 domain and that this step requires dynein-mediated basipetal transport. It also requires RAB6 and its effector GARP (Vps51/Vps52/Vps53/Vps54), whose composition we determined by MS/MS following affinity chromatography purification. Ablation of any GARP component diverts ChsB to vacuoles and impairs growth and morphology markedly, emphasizing the important physiological role played by this pathway that, we propose, is central to the hyphal mode of growth. Filamentous fungi form long tubular cells, called hyphae, which grow rapidly by apical extension, enabling these sessile organisms to explore substrates and facilitating tissue invasion in the case of pathogenic species. Because the shape of the hyphae is determined by an external cell wall, hyphal growth requires that cell-wall sculpting enzymes polarize to the tips. Endocytosis is essential for hyphal growth, and it was suspected that this results from its participation in a recycling pathway that takes up cell-wall enzymes from the plasma membrane and re-delivers them to the apex. Here we track the trafficking of a chitin synthase (a cell-wall modifying enzyme) to demonstrate that it is polarized by endocytic recycling. This chitin synthase is delivered by exocytosis to the apex, but diffuses away until being captured by a subapical collar of actin patches (sites of endocytosis) from where it reaches a sorting endosome before undergoing transport to the nearest trans-Golgi cisternae and incorporating into secretory vesicles that re-deliver the enzyme to the apex. Because impairing transit across this pathway compromises apical extension markedly and results in severe morphological defects, the pathway could be manipulated to prevent fungal pathogenicity of plants and humans, an enormous burden on human welfare.
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Affiliation(s)
- Miguel Hernández-González
- Department of Cellular and Molecular Biology and Intradepartmental WhiteBiotech Unit, Centro de Investigaciones Biológicas del Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu, Madrid, Spain
| | - Ignacio Bravo-Plaza
- Department of Cellular and Molecular Biology and Intradepartmental WhiteBiotech Unit, Centro de Investigaciones Biológicas del Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu, Madrid, Spain
| | - Mario Pinar
- Department of Cellular and Molecular Biology and Intradepartmental WhiteBiotech Unit, Centro de Investigaciones Biológicas del Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu, Madrid, Spain
| | - Vivian de los Ríos
- Proteomics Facility, Centro de Investigaciones Biológicas del Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu, Madrid, Spain
| | - Herbert N. Arst
- Section of Microbiology, Imperial College London, Flowers Building, Armstrong Road, London, United Kingdom
| | - Miguel A. Peñalva
- Department of Cellular and Molecular Biology and Intradepartmental WhiteBiotech Unit, Centro de Investigaciones Biológicas del Consejo Superior de Investigaciones Científicas, Ramiro de Maeztu, Madrid, Spain
- * E-mail:
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44
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Climer LK, Pokrovskaya ID, Blackburn JB, Lupashin VV. Membrane detachment is not essential for COG complex function. Mol Biol Cell 2018; 29:964-974. [PMID: 29467253 PMCID: PMC5896934 DOI: 10.1091/mbc.e17-11-0694] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
COG is a multisubunit vesicle tethering complex in the Golgi. We demonstrate that both COG subcomplexes can be permanently attached to Golgi membranes and that major COG functions do not require cycling between the membrane and cytosol. The conserved oligomeric Golgi (COG) complex is a vesicle tether of the “complexes associated with tethering containing helical rods” family, which functions on the cytoplasmic side of Golgi. It is currently unknown whether COG function, or function of any multisubunit vesicular tether, depends on cycling between the membrane and cytosol. Therefore, we permanently anchored key subunits of COG subcomplexes (COG4, COG7, and COG8) to Golgi membranes using transmembrane protein TMEM115 (TMEM-COG). All TMEM-COG subunits tested were Golgi localized, integrated into the COG complex, and stabilized membrane association of endogenous subunits. Interestingly, TMEM-COG4 and TMEM-COG7 equally rescued COG function in organization of Golgi markers, glycosylation, and abundance of COG-sensitive proteins. In contrast, TMEM-COG8 was not as effective, indicating that N-terminal attachment of COG8 interfered with overall COG structure and function, and none of the TMEM-COG subunits rescued the abnormal Golgi architecture caused by COG knockout. Collectively, these data indicate that both subcomplexes of the COG complex can perform most of COG function when permanently attached to membranes and that the cytosolic pool of COG is not completely essential to COG function.
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Affiliation(s)
- Leslie K Climer
- College of Medicine, Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, AR 72205
| | - Irina D Pokrovskaya
- College of Medicine, Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, AR 72205
| | - Jessica B Blackburn
- College of Medicine, Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, AR 72205
| | - Vladimir V Lupashin
- College of Medicine, Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, AR 72205
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45
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Hussain S, Le Guezennec X, Yi W, Dong H, Chia J, Yiping K, Khoon LK, Bard F. Digging deep into Golgi phenotypic diversity with unsupervised machine learning. Mol Biol Cell 2017; 28:3686-3698. [PMID: 29021342 PMCID: PMC5706995 DOI: 10.1091/mbc.e17-06-0379] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 09/08/2017] [Accepted: 10/04/2017] [Indexed: 11/24/2022] Open
Abstract
Structural alterations of the Golgi apparatus may lead to phenotypes that human vision cannot easily discriminate. In this work, we present a high-content analysis framework including an unsupervised clustering step to automatically uncover Golgi phenotypic diversity. We use this deep phenotyping to quantitatively compare the effects of gene depletion. The synthesis of glycans and the sorting of proteins are critical functions of the Golgi apparatus and depend on its highly complex and compartmentalized architecture. High-content image analysis coupled to RNA interference screening offers opportunities to explore this organelle organization and the gene network underlying it. To date, image-based Golgi screens have based on a single parameter or supervised analysis with predefined Golgi structural classes. Here, we report the use of multiparametric data extracted from a single marker and a computational unsupervised analysis framework to explore Golgi phenotypic diversity more extensively. In contrast with the three visually definable phenotypes, our framework reproducibly identified 10 Golgi phenotypes. They were used to quantify and stratify phenotypic similarities among genetic perturbations. The derived phenotypic network partially overlaps previously reported protein–protein interactions as well as suggesting novel functional interactions. Our workflow suggests the existence of multiple stable Golgi organizational states and provides a proof of concept for the classification of drugs and genes using fine-grained phenotypic information.
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Affiliation(s)
| | | | - Wang Yi
- Institute of High Performance Computing, Singapore 138673
| | - Huang Dong
- Institute of High Performance Computing, Singapore 138673
| | - Joanne Chia
- Institute of Molecular and Cell Biology, Singapore 138673
| | - Ke Yiping
- School of Computer Science and Engineering, Nanyang Technological University, Singapore 639798
| | - Lee Kee Khoon
- Institute of High Performance Computing, Singapore 138673
| | - Frédéric Bard
- Institute of Molecular and Cell Biology, Singapore 138673
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46
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Wang T, Li L, Hong W. SNARE proteins in membrane trafficking. Traffic 2017; 18:767-775. [PMID: 28857378 DOI: 10.1111/tra.12524] [Citation(s) in RCA: 99] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 08/25/2017] [Accepted: 08/25/2017] [Indexed: 12/25/2022]
Abstract
SNAREs are the core machinery mediating membrane fusion. In this review, we provide an update on the recent progress on SNAREs regulating membrane fusion events, especially the more detailed fusion processes dissected by well-developed biophysical methods and in vitro single molecule analysis approaches. We also briefly summarize the relevant research from Chinese laboratories and highlight the significant contributions on our understanding of SNARE-mediated membrane trafficking from scientists in China.
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Affiliation(s)
- Tuanlao Wang
- School of Pharmaceutical Sciences, State Key Laboratory of Cellular Stress Biology, Xiamen University, Xiamen, China
| | - Liangcheng Li
- School of Pharmaceutical Sciences, State Key Laboratory of Cellular Stress Biology, Xiamen University, Xiamen, China
| | - Wanjin Hong
- School of Pharmaceutical Sciences, State Key Laboratory of Cellular Stress Biology, Xiamen University, Xiamen, China.,Institute of Molecular and Cell Biology, A*STAR (Agency for Science, Technology and Research), Singapore, Singapore
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47
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Dolat L, Valdivia RH. Bacterial Subversion of COG-Dependent Membrane Traffic. Trends Cell Biol 2017; 27:877-878. [PMID: 28988619 DOI: 10.1016/j.tcb.2017.09.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 09/22/2017] [Indexed: 11/25/2022]
Abstract
Intracellular bacterial pathogens thrive within eukaryotic cells by interacting with a range of organelles to establish a replicative niche. In a new study in Cell Host and Microbe, Miller et al. identify a Brucella abortus effector that subverts membrane and protein transport to the Golgi apparatus to promote bacterial replication.
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Affiliation(s)
- Lee Dolat
- Department of Molecular Genetics and Microbiology and Center for Host-Microbe Interactions, Duke University School of Medicine, Durham, NC, USA
| | - Raphael H Valdivia
- Department of Molecular Genetics and Microbiology and Center for Host-Microbe Interactions, Duke University School of Medicine, Durham, NC, USA.
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48
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Miller CN, Smith EP, Cundiff JA, Knodler LA, Bailey Blackburn J, Lupashin V, Celli J. A Brucella Type IV Effector Targets the COG Tethering Complex to Remodel Host Secretory Traffic and Promote Intracellular Replication. Cell Host Microbe 2017; 22:317-329.e7. [PMID: 28844886 PMCID: PMC5599354 DOI: 10.1016/j.chom.2017.07.017] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2017] [Revised: 06/16/2017] [Accepted: 07/27/2017] [Indexed: 10/19/2022]
Abstract
Many intracellular pathogens exploit host secretory trafficking to support their intracellular cycle, but knowledge of these pathogenic processes is limited. The bacterium Brucella abortus uses a type IV secretion system (VirB T4SS) to generate a replication-permissive Brucella-containing vacuole (rBCV) derived from the host ER, a process that requires host early secretory trafficking. Here we show that the VirB T4SS effector BspB contributes to rBCV biogenesis and Brucella replication by interacting with the conserved oligomeric Golgi (COG) tethering complex, a major coordinator of Golgi vesicular trafficking, thus remodeling Golgi membrane traffic and redirecting Golgi-derived vesicles to the BCV. Altogether, these findings demonstrate that Brucella modulates COG-dependent trafficking via delivery of a T4SS effector to promote rBCV biogenesis and intracellular proliferation, providing mechanistic insight into how bacterial exploitation of host secretory functions promotes pathogenesis.
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Affiliation(s)
- Cheryl N Miller
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA 99164, USA
| | - Erin P Smith
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA 99164, USA
| | - Jennifer A Cundiff
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA 99164, USA
| | - Leigh A Knodler
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA 99164, USA
| | - Jessica Bailey Blackburn
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Vladimir Lupashin
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | - Jean Celli
- Paul G. Allen School for Global Animal Health, Washington State University, Pullman, WA 99164, USA.
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49
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Frappaolo A, Sechi S, Kumagai T, Robinson S, Fraschini R, Karimpour-Ghahnavieh A, Belloni G, Piergentili R, Tiemeyer KH, Tiemeyer M, Giansanti MG. COG7 deficiency in Drosophila generates multifaceted developmental, behavioral and protein glycosylation phenotypes. J Cell Sci 2017; 130:3637-3649. [PMID: 28883096 DOI: 10.1242/jcs.209049] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Accepted: 09/04/2017] [Indexed: 12/14/2022] Open
Abstract
Congenital disorders of glycosylation (CDG) comprise a family of human multisystemic diseases caused by recessive mutations in genes required for protein N-glycosylation. More than 100 distinct forms of CDGs have been identified and most of them cause severe neurological impairment. The Conserved Oligomeric Golgi (COG) complex mediates tethering of vesicles carrying glycosylation enzymes across the Golgi cisternae. Mutations affecting human COG1, COG2 and COG4-COG8 cause monogenic forms of inherited, autosomal recessive CDGs. We have generated a Drosophila COG7-CDG model that closely parallels the pathological characteristics of COG7-CDG patients, including pronounced neuromotor defects associated with altered N-glycome profiles. Consistent with these alterations, larval neuromuscular junctions of Cog7 mutants exhibit a significant reduction in bouton numbers. We demonstrate that the COG complex cooperates with Rab1 and Golgi phosphoprotein 3 to regulate Golgi trafficking and that overexpression of Rab1 can rescue the cytokinesis and locomotor defects associated with loss of Cog7. Our results suggest that the Drosophila COG7-CDG model can be used to test novel potential therapeutic strategies by modulating trafficking pathways.
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Affiliation(s)
- Anna Frappaolo
- Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Biologia e Biotecnologie, Università Sapienza di Roma, Roma, Piazzale A. Moro 5, 00185 Roma, Italy
| | - Stefano Sechi
- Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Biologia e Biotecnologie, Università Sapienza di Roma, Roma, Piazzale A. Moro 5, 00185 Roma, Italy
| | - Tadahiro Kumagai
- Complex Carbohydrate Research Center, The University of Georgia, 315 Riverbend Rd., Athens, GA 30602, USA
| | - Sarah Robinson
- Complex Carbohydrate Research Center, The University of Georgia, 315 Riverbend Rd., Athens, GA 30602, USA
| | - Roberta Fraschini
- Dipartimento di Biotecnologie e Bioscienze, Università degli studi di Milano Bicocca, 20126 Milano, Italy
| | - Angela Karimpour-Ghahnavieh
- Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Biologia e Biotecnologie, Università Sapienza di Roma, Roma, Piazzale A. Moro 5, 00185 Roma, Italy
| | - Giorgio Belloni
- Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Biologia e Biotecnologie, Università Sapienza di Roma, Roma, Piazzale A. Moro 5, 00185 Roma, Italy
| | - Roberto Piergentili
- Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Biologia e Biotecnologie, Università Sapienza di Roma, Roma, Piazzale A. Moro 5, 00185 Roma, Italy
| | - Katherine H Tiemeyer
- Complex Carbohydrate Research Center, The University of Georgia, 315 Riverbend Rd., Athens, GA 30602, USA
| | - Michael Tiemeyer
- Complex Carbohydrate Research Center, The University of Georgia, 315 Riverbend Rd., Athens, GA 30602, USA .,Department of Biochemistry and Molecular Biology, The University of Georgia, B122 Life Sciences Building, Athens, GA 30602, USA
| | - Maria Grazia Giansanti
- Istituto di Biologia e Patologia Molecolari del CNR, Dipartimento di Biologia e Biotecnologie, Università Sapienza di Roma, Roma, Piazzale A. Moro 5, 00185 Roma, Italy
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50
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Haijes HA, Jaeken J, Foulquier F, van Hasselt PM. Hypothesis: lobe A (COG1–4)-CDG causes a more severe phenotype than lobe B (COG5–8)-CDG. J Med Genet 2017; 55:137-142. [DOI: 10.1136/jmedgenet-2017-104586] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Revised: 06/07/2017] [Accepted: 06/21/2017] [Indexed: 01/26/2023]
Abstract
The conserved oligomeric Golgi (COG) complex consists of eight subunits organized in two lobes: lobe A (COG1–4) and lobe B (COG5–8). The different functional roles of COG lobe A and lobe B might result in distinct clinical phenotypes in patients with COG-CDG (congenital disorders of glycosylation). This hypothesis is supported by three observations. First, knock-down of COG lobe A components affects Golgi morphology more severely than knock-down of COG lobe B components. Second, nearly all of the 27 patients with lobe B COG-CDG had bi-allelic truncating mutations, as compared with only one of the six patients with lobe A COG-CDG. This represents a frequency gap which suggests that bi-allelic truncating mutations in COG lobe A genes might be non-viable. Third, in support, large-scale exome data of healthy adults (Exome Aggregation Consortium (ExAC)) underline that COG lobe A genes are less tolerant to genetic variation than COG lobe B genes. Thus, comparable molecular defects are more detrimental in lobe A COG-CDG than in lobe B COG-CDG. In a larger perspective, clinical phenotypic severity corresponded nicely with tolerance to genetic variation. Therefore, genomic epidemiology can potentially be used as a photographic negative for mutational severity.
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