1
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Zhu Y, Chen Y, Zhang F, Wang M, Lai Y, Pan J, Liu Y, Wang Q, Chen S. Novel ZFPL1::NUP98 fusion gene identified in an adult acute myeloid leukemia patient. Int J Lab Hematol 2024; 46:568-570. [PMID: 38318992 DOI: 10.1111/ijlh.14239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Accepted: 01/17/2024] [Indexed: 02/07/2024]
Affiliation(s)
- Yiyan Zhu
- National Clinical Research Center for Hematologic Diseases, Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, People's Republic of China
- Institute of Blood and Marrow Transplantation, Collaborative Innovation Center of Hematology, Soochow University, Suzhou, People's Republic of China
| | - Yu Chen
- Department of Hematology, The Second Affiliated Hospital of Wannan Medical College, Wuhu, People's Republic of China
| | - Fenghong Zhang
- National Clinical Research Center for Hematologic Diseases, Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, People's Republic of China
- Institute of Blood and Marrow Transplantation, Collaborative Innovation Center of Hematology, Soochow University, Suzhou, People's Republic of China
| | - Man Wang
- National Clinical Research Center for Hematologic Diseases, Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, People's Republic of China
- Institute of Blood and Marrow Transplantation, Collaborative Innovation Center of Hematology, Soochow University, Suzhou, People's Republic of China
| | - Yueyun Lai
- National Clinical Research Center for Hematologic Diseases, Beijing Key Laboratory of Hematopoietic Stem Cell Transplantation, Peking University Institute of Hematology, Peking University People's Hospital, Peking University, Beijing, People's Republic of China
| | - Jinlan Pan
- National Clinical Research Center for Hematologic Diseases, Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, People's Republic of China
- Institute of Blood and Marrow Transplantation, Collaborative Innovation Center of Hematology, Soochow University, Suzhou, People's Republic of China
| | - Yizi Liu
- National Clinical Research Center for Hematologic Diseases, Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, People's Republic of China
- Institute of Blood and Marrow Transplantation, Collaborative Innovation Center of Hematology, Soochow University, Suzhou, People's Republic of China
| | - Qian Wang
- National Clinical Research Center for Hematologic Diseases, Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, People's Republic of China
- Institute of Blood and Marrow Transplantation, Collaborative Innovation Center of Hematology, Soochow University, Suzhou, People's Republic of China
| | - Suning Chen
- National Clinical Research Center for Hematologic Diseases, Jiangsu Institute of Hematology, The First Affiliated Hospital of Soochow University, Suzhou, People's Republic of China
- Institute of Blood and Marrow Transplantation, Collaborative Innovation Center of Hematology, Soochow University, Suzhou, People's Republic of China
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2
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Ugur B, Schueder F, Shin J, Hanna MG, Wu Y, Leonzino M, Su M, McAdow AR, Wilson C, Postlethwait J, Solnica-Krezel L, Bewersdorf J, De Camilli P. VPS13B is localized at the cis-trans Golgi complex interface and is a functional partner of FAM177A1. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.18.572081. [PMID: 38187698 PMCID: PMC10769246 DOI: 10.1101/2023.12.18.572081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2024]
Abstract
Mutations in VPS13B, a member of a protein family implicated in bulk lipid transport between adjacent membranes, cause Cohen syndrome. VPS13B is known to be concentrated in the Golgi complex, but its precise location within this organelle and thus the site(s) where it achieves lipid transport remains unclear. Here we show that VPS13B is localized at the interface between cis and trans Golgi sub-compartments and that Golgi complex re-formation after Brefeldin A (BFA) induced disruption is delayed in VPS13B KO cells. This delay is phenocopied by loss of FAM177A1, a Golgi complex protein of unknown function reported to be a VPS13B interactor and whose mutations also result in a developmental disorder. In zebrafish, the vps13b orthologue, not previously annotated in this organism, genetically interacts with fam177a1. Collectively, these findings raise the possibility that bulk lipid transport by VPS13B may play a role in expanding Golgi membranes and that VPS13B may be assisted in this function by FAM177A1.
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Affiliation(s)
- Berrak Ugur
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA
- Program in Cellular Neuroscience, Neurodegeneration, and Repair, Yale University School of Medicine, New Haven, CT, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD, USA
- HHMI, Yale University School of Medicine, New Haven, CT, USA
| | - Florian Schueder
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA
| | - Jimann Shin
- Department of Developmental Biology, Washington University School of Medicine, St Louis, MO, USA
| | - Michael G. Hanna
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA
- Program in Cellular Neuroscience, Neurodegeneration, and Repair, Yale University School of Medicine, New Haven, CT, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD, USA
- HHMI, Yale University School of Medicine, New Haven, CT, USA
| | - Yumei Wu
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA
- Program in Cellular Neuroscience, Neurodegeneration, and Repair, Yale University School of Medicine, New Haven, CT, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD, USA
- HHMI, Yale University School of Medicine, New Haven, CT, USA
| | - Marianna Leonzino
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA
- Program in Cellular Neuroscience, Neurodegeneration, and Repair, Yale University School of Medicine, New Haven, CT, USA
- HHMI, Yale University School of Medicine, New Haven, CT, USA
| | - Maohan Su
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
| | - Anthony R. McAdow
- Department of Developmental Biology, Washington University School of Medicine, St Louis, MO, USA
| | - Catherine Wilson
- Institute of Neuroscience, University of Oregon, Eugene, OR, USA
| | | | - Lilianna Solnica-Krezel
- Department of Developmental Biology, Washington University School of Medicine, St Louis, MO, USA
| | - Joerg Bewersdorf
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
- Nanobiology Institute, Yale University, West Haven, CT, USA
- Department of Biomedical Engineering, Yale University, New Haven, CT, USA
- Department of Physics, Yale University, New Haven, CT, USA
| | - Pietro De Camilli
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA
- Program in Cellular Neuroscience, Neurodegeneration, and Repair, Yale University School of Medicine, New Haven, CT, USA
- Aligning Science Across Parkinson’s (ASAP) Collaborative Research Network, Chevy Chase, MD, USA
- HHMI, Yale University School of Medicine, New Haven, CT, USA
- Department of Microbial Pathogenesis, Yale University School of Medicine, New Haven, CT, USA
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3
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Pascual-Alonso A, Xiol C, Smirnov D, Kopajtich R, Prokisch H, Armstrong J. Identification of molecular signatures and pathways involved in Rett syndrome using a multi-omics approach. Hum Genomics 2023; 17:85. [PMID: 37710353 PMCID: PMC10503149 DOI: 10.1186/s40246-023-00532-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2023] [Accepted: 09/03/2023] [Indexed: 09/16/2023] Open
Abstract
BACKGROUND Rett syndrome (RTT) is a neurodevelopmental disorder mainly caused by mutations in the methyl-CpG-binding protein 2 gene (MECP2). MeCP2 is a multi-functional protein involved in many cellular processes, but the mechanisms by which its dysfunction causes disease are not fully understood. The duplication of the MECP2 gene causes a distinct disorder called MECP2 duplication syndrome (MDS), highlighting the importance of tightly regulating its dosage for proper cellular function. Additionally, some patients with mutations in genes other than MECP2 exhibit phenotypic similarities with RTT, indicating that these genes may also play a role in similar cellular functions. The purpose of this study was to characterise the molecular alterations in patients with RTT in order to identify potential biomarkers or therapeutic targets for this disorder. METHODS We used a combination of transcriptomics (RNAseq) and proteomics (TMT mass spectrometry) to characterise the expression patterns in fibroblast cell lines from 22 patients with RTT and detected mutation in MECP2, 15 patients with MDS, 12 patients with RTT-like phenotypes and 13 healthy controls. Transcriptomics and proteomics data were used to identify differentially expressed genes at both RNA and protein levels, which were further inspected via enrichment and upstream regulator analyses and compared to find shared features in patients with RTT. RESULTS We identified molecular alterations in cellular functions and pathways that may contribute to the disease phenotype in patients with RTT, such as deregulated cytoskeletal components, vesicular transport elements, ribosomal subunits and mRNA processing machinery. We also compared RTT expression profiles with those of MDS seeking changes in opposite directions that could lead to the identification of MeCP2 direct targets. Some of the deregulated transcripts and proteins were consistently affected in patients with RTT-like phenotypes, revealing potentially relevant molecular processes in patients with overlapping traits and different genetic aetiology. CONCLUSIONS The integration of data in a multi-omics analysis has helped to interpret the molecular consequences of MECP2 dysfunction, contributing to the characterisation of the molecular landscape in patients with RTT. The comparison with MDS provides knowledge of MeCP2 direct targets, whilst the correlation with RTT-like phenotypes highlights processes potentially contributing to the pathomechanism leading these disorders.
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Affiliation(s)
- Ainhoa Pascual-Alonso
- Fundació Per La Recerca Sant Joan de Déu, Esplugues de Llobregat, Spain
- Institut de Recerca Sant Joan de Déu, Esplugues de Llobregat, Spain
| | - Clara Xiol
- Fundació Per La Recerca Sant Joan de Déu, Esplugues de Llobregat, Spain
- Institut de Recerca Sant Joan de Déu, Esplugues de Llobregat, Spain
| | - Dmitrii Smirnov
- Institute of Human Genetics, Technical University of Munich, Munich, Germany
- Institute of Neurogenomics, Helmholtz Zentrum München, Munich, Germany
| | - Robert Kopajtich
- Institute of Human Genetics, Technical University of Munich, Munich, Germany
- Institute of Neurogenomics, Helmholtz Zentrum München, Munich, Germany
| | - Holger Prokisch
- Institute of Human Genetics, Technical University of Munich, Munich, Germany
- Institute of Neurogenomics, Helmholtz Zentrum München, Munich, Germany
| | - Judith Armstrong
- Institut de Recerca Sant Joan de Déu, Esplugues de Llobregat, Spain.
- CIBER-ER (Biomedical Network Research Center for Rare Diseases), Instituto de Salud Carlos III (ISCIII), Madrid, Spain.
- Genomic Unit, Molecular and Genetic Medicine Section, Hospital Sant Joan de Déu, Barcelona, Spain.
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4
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Buzuk L, Hellerschmied D. Ubiquitin-mediated degradation at the Golgi apparatus. Front Mol Biosci 2023; 10:1197921. [PMID: 37484530 PMCID: PMC10357820 DOI: 10.3389/fmolb.2023.1197921] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Accepted: 06/26/2023] [Indexed: 07/25/2023] Open
Abstract
The Golgi apparatus is an essential organelle of the secretory pathway in eukaryotic cells. It processes secretory and transmembrane proteins and orchestrates their transport to other endomembrane compartments or the plasma membrane. The Golgi apparatus thereby shapes the cell surface, controlling cell polarity, cell-cell communication, and immune signaling. The cytosolic face of the Golgi hosts and regulates signaling cascades, impacting most notably the DNA damage response and mitosis. These essential functions strongly depend on Golgi protein homeostasis and Golgi integrity. Golgi fragmentation and consequent malfunction is associated with neurodegenerative diseases and certain cancer types. Recent studies provide first insight into the critical role of ubiquitin signaling in maintaining Golgi integrity and in Golgi protein quality control. Similar to well described pathways at the endoplasmic reticulum, ubiquitin-dependent degradation of non-native proteins prevents the accumulation of toxic protein aggregates at the Golgi. Moreover, ubiquitination regulates Golgi structural rearrangements in response to cellular stress. Advances in elucidating ubiquitination and degradation events at the Golgi are starting to paint a picture of the molecular machinery underlying Golgi (protein) homeostasis.
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5
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Masud N, Aldahish A, Iczkowski KA, Kale A, Shah GV. Zinc finger protein‑like 1 is a novel neuroendocrine biomarker for prostate cancer. Int J Oncol 2023; 62:38. [PMID: 36799165 PMCID: PMC9937688 DOI: 10.3892/ijo.2023.5486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 07/26/2022] [Indexed: 02/08/2023] Open
Abstract
Prostate‑derived calcitonin (CT) and its receptor induce tumorigenicity and increase metastatic potential of prostate cancer (PC). CT‑inducible genes in human prostate were identified by subtraction hybridization. Among these genes, zinc finger protein like 1 (ZFPL1) protein was interesting since it was abundantly expressed in malignant prostates but was almost absent in benign prostates. ZFPL1 expression was upregulated by CT and androgens, and ZFPL1 protein was secreted by prostate tumor cells through exosomal secretion. Serum levels of ZFPL1 in cancer patients were at least 4‑fold higher than those in the sera of cancer‑free individuals. Cell biology of ZFPL1 suggests its localization in Golgi bodies and exosomes, and its colocalization with chromogranin A and CD44. These results suggested that ZFPL1 is secreted by tumor cells of neuroendocrine (NE)/stem cell phenotype. The knockdown of endogenous ZFPL1 in (PC) cells led to a remarkable decrease in cell proliferation, and invasion while increasing their apoptosis. As expected, the overexpression of ZFPL1 in prostate cells had an opposite effect on these functions. The knockdown of ZFPL1 in PC cells also decreased Akt phosphorylation, suggesting the actions of ZFPL1 may be mediated through the PI3K‑Akt pathway. Moreover, the present results revealed that ZFPL1 is released by tumors cells of NE or androgen‑independent phenotype and its serum levels are significantly higher in cancer patients, suggesting that it may serve as a blood‑based non‑invasive biomarker of aggressive PC.
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Affiliation(s)
- Neshat Masud
- Pharmacology, College of Pharmacy, University of Louisiana at Monroe, Monroe, LA 71209, USA
| | - Afaf Aldahish
- Pharmacology, College of Pharmacy, University of Louisiana at Monroe, Monroe, LA 71209, USA
- Department of Pharmacology and Toxicology, College of Pharmacy, King Khalid University, Abha 61421, Saudi Arabia
| | - Kenneth A. Iczkowski
- Pathology and Laboratory Medicine, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Ajay Kale
- Pharmacology, College of Pharmacy, University of Louisiana at Monroe, Monroe, LA 71209, USA
| | - Girish V. Shah
- Pharmacology, College of Pharmacy, University of Louisiana at Monroe, Monroe, LA 71209, USA
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6
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Arab M, Nayak SC, Vitali T, Lowe M. Immunofluorescence Microscopy of the Mammalian Golgi Apparatus. Methods Mol Biol 2022; 2557:101-111. [PMID: 36512212 DOI: 10.1007/978-1-0716-2639-9_8] [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
Immunofluorescence is a technique that uses antibodies and fluorophores to label structures inside cells. The cells are normally fixed and permeabilized, and then structures are labelled using primary antibodies directly conjugated to fluorophores, or, more commonly, first with an antibody against an antigen of interest followed by a secondary antibody conjugated to a fluorophore that binds to the primary antibody. Fluorescence can be visualized using widefield, confocal, or super-resolution microscopy. Here we focus on labelling of the Golgi apparatus and show that different fixation and permeabilization conditions can significantly affect labelling of Golgi proteins and describe how to optimize fluorescent detection of Golgi proteins.
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Affiliation(s)
- Maryam Arab
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Sanjeev Chavan Nayak
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Teresa Vitali
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK
| | - Martin Lowe
- School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, UK.
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7
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Rusilowicz-Jones EV, Brazel AJ, Frigenti F, Urbé S, Clague MJ. Membrane compartmentalisation of the ubiquitin system. Semin Cell Dev Biol 2022; 132:171-184. [PMID: 34895815 DOI: 10.1016/j.semcdb.2021.11.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 11/12/2021] [Accepted: 11/15/2021] [Indexed: 12/15/2022]
Abstract
We now have a comprehensive inventory of ubiquitin system components. Understanding of any system also needs an appreciation of how components are organised together. Quantitative proteomics has provided us with a census of their relative populations in several model cell types. Here, by examining large scale unbiased data sets, we seek to identify and map those components, which principally reside on the major organelles of the endomembrane system. We present the consensus distribution of > 50 ubiquitin modifying enzymes, E2s, E3s and DUBs, that possess transmembrane domains. This analysis reveals that the ER and endosomal compartments have a diverse cast of resident E3s, whilst the Golgi and mitochondria operate with a more restricted palette. We describe key functions of ubiquitylation that are specific to each compartment and relate this to their signature complement of ubiquitin modifying components.
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Affiliation(s)
- Emma V Rusilowicz-Jones
- Dept. of Molecular Physiology and Cell Signaling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 3BX, UK
| | - Ailbhe J Brazel
- Dept. of Molecular Physiology and Cell Signaling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 3BX, UK; Department of Biology, Maynooth University, Maynooth W23 F2K6, Ireland
| | - Francesca Frigenti
- Dept. of Molecular Physiology and Cell Signaling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 3BX, UK
| | - Sylvie Urbé
- Dept. of Molecular Physiology and Cell Signaling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 3BX, UK.
| | - Michael J Clague
- Dept. of Molecular Physiology and Cell Signaling, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool L69 3BX, UK.
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8
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Gaspar CJ, Vieira LC, Santos CC, Christianson JC, Jakubec D, Strisovsky K, Adrain C, Domingos PM. EMC is required for biogenesis of Xport-A, an essential chaperone of Rhodopsin-1 and the TRP channel. EMBO Rep 2022; 23:e53210. [PMID: 34918864 PMCID: PMC8728618 DOI: 10.15252/embr.202153210] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 10/26/2021] [Accepted: 11/10/2021] [Indexed: 01/07/2023] Open
Abstract
The ER membrane protein complex (EMC) is required for the biogenesis of a subset of tail anchored (TA) and polytopic membrane proteins, including Rhodopsin-1 (Rh1) and the TRP channel. To understand the physiological implications of EMC-dependent membrane protein biogenesis, we perform a bioinformatic identification of Drosophila TA proteins. From 254 predicted TA proteins, screening in larval eye discs identified two proteins that require EMC for their biogenesis: fan and Xport-A. Fan is required for male fertility in Drosophila and we show that EMC is also required for this process. Xport-A is essential for the biogenesis of both Rh1 and TRP, raising the possibility that disruption of Rh1 and TRP biogenesis in EMC mutants is secondary to the Xport-A defect. We show that EMC is required for Xport-A TMD membrane insertion and that EMC-independent Xport-A mutants rescue Rh1 and TRP biogenesis in EMC mutants. Finally, our work also reveals a role for Xport-A in a glycosylation-dependent triage mechanism during Rh1 biogenesis in the endoplasmic reticulum.
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Affiliation(s)
- Catarina J Gaspar
- Instituto de Tecnologia Química e Biológica da Universidade Nova de Lisboa (ITQB‐NOVA)OeirasPortugal
- Membrane Traffic LabInstituto Gulbenkian de Ciência (IGC)OeirasPortugal
| | - Lígia C Vieira
- Instituto de Tecnologia Química e Biológica da Universidade Nova de Lisboa (ITQB‐NOVA)OeirasPortugal
- Present address:
Center for Genomics and Systems BiologyNew York University Abu DhabiAbu DhabiUnited Arab Emirates
| | - Cristiana C Santos
- Instituto de Tecnologia Química e Biológica da Universidade Nova de Lisboa (ITQB‐NOVA)OeirasPortugal
| | - John C Christianson
- Nuffield Department of Orthopaedics, Rheumatology and Musculoskeletal SciencesBotnar Research CentreUniversity of OxfordOxfordUK
| | - David Jakubec
- Institute of Organic Chemistry and BiochemistryCzech Academy of SciencesPragueCzech Republic
| | - Kvido Strisovsky
- Institute of Organic Chemistry and BiochemistryCzech Academy of SciencesPragueCzech Republic
| | - Colin Adrain
- Membrane Traffic LabInstituto Gulbenkian de Ciência (IGC)OeirasPortugal
- Patrick G Johnston Centre for Cancer ResearchQueen’s UniversityBelfastUK
| | - Pedro M Domingos
- Instituto de Tecnologia Química e Biológica da Universidade Nova de Lisboa (ITQB‐NOVA)OeirasPortugal
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9
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Congenital disorder of glycosylation caused by starting site-specific variant in syntaxin-5. Nat Commun 2021; 12:6227. [PMID: 34711829 PMCID: PMC8553859 DOI: 10.1038/s41467-021-26534-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Accepted: 10/05/2021] [Indexed: 12/26/2022] Open
Abstract
The SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor) protein syntaxin-5 (Stx5) is essential for Golgi transport. In humans, the STX5 mRNA encodes two protein isoforms, Stx5 Long (Stx5L) from the first starting methionine and Stx5 Short (Stx5S) from an alternative starting methionine at position 55. In this study, we identify a human disorder caused by a single missense substitution in the second starting methionine (p.M55V), resulting in complete loss of the short isoform. Patients suffer from an early fatal multisystem disease, including severe liver disease, skeletal abnormalities and abnormal glycosylation. Primary human dermal fibroblasts isolated from these patients show defective glycosylation, altered Golgi morphology as measured by electron microscopy, mislocalization of glycosyltransferases, and compromised ER-Golgi trafficking. Measurements of cognate binding SNAREs, based on biotin-synchronizable forms of Stx5 (the RUSH system) and Förster resonance energy transfer (FRET), revealed that the short isoform of Stx5 is essential for intra-Golgi transport. Alternative starting codons of Stx5 are thus linked to human disease, demonstrating that the site of translation initiation is an important new layer of regulating protein trafficking.
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10
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Pérez-Rodriguez S, Wulff T, Voldborg BG, Altamirano C, Trujillo-Roldán MA, Valdez-Cruz NA. Compartmentalized Proteomic Profiling Outlines the Crucial Role of the Classical Secretory Pathway during Recombinant Protein Production in Chinese Hamster Ovary Cells. ACS OMEGA 2021; 6:12439-12458. [PMID: 34056395 PMCID: PMC8154153 DOI: 10.1021/acsomega.0c06030] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 02/24/2021] [Indexed: 05/11/2023]
Abstract
Different cellular processes that contribute to protein production in Chinese hamster ovary (CHO) cells have been previously investigated by proteomics. However, although the classical secretory pathway (CSP) has been well documented as a bottleneck during recombinant protein (RP) production, it has not been well represented in previous proteomic studies. Hence, the significance of this pathway for production of RP was assessed by identifying its own proteins that were associated to changes in RP production, through subcellular fractionation coupled to shot-gun proteomics. Two CHO cell lines producing a monoclonal antibody with different specific productivities were used as cellular models, from which 4952 protein groups were identified, which represent a coverage of 59% of the Chinese hamster proteome. Data are available via ProteomeXchange with identifier PXD021014. By using SAM and ROTS algorithms, 493 proteins were classified as differentially expressed, of which about 80% was proposed as novel targets and one-third were assigned to the CSP. Endoplasmic reticulum (ER) stress, unfolded protein response, calcium homeostasis, vesicle traffic, glycosylation, autophagy, proteasomal activity, protein synthesis and translocation into ER lumen, and secretion of extracellular matrix components were some of the affected processes that occurred in the secretory pathway. Processes from other cellular compartments, such as DNA replication, transcription, cytoskeleton organization, signaling, and metabolism, were also modified. This study gives new insights into the molecular traits of higher producer cells and provides novel targets for development of new sub-lines with improved phenotypes for RP production.
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Affiliation(s)
- Saumel Pérez-Rodriguez
- Programa
de Investigación de Producción de Biomoléculas,
Departamento de Biología Molecular y Biotecnología,
Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Coyoacán 04510 Ciudad de
México, México
| | - Tune Wulff
- The
Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kgs. Lyngby 2800, Denmark
| | - Bjørn G. Voldborg
- The
Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Kgs. Lyngby 2800, Denmark
| | - Claudia Altamirano
- Laboratorio
de Cultivos Celulares, Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, Avenida Brasil 2085 Valparaíso, Chile
| | - Mauricio A. Trujillo-Roldán
- Programa
de Investigación de Producción de Biomoléculas,
Departamento de Biología Molecular y Biotecnología,
Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Coyoacán 04510 Ciudad de
México, México
| | - Norma A. Valdez-Cruz
- Programa
de Investigación de Producción de Biomoléculas,
Departamento de Biología Molecular y Biotecnología,
Instituto de Investigaciones Biomédicas, Universidad Nacional Autónoma de México, Ciudad Universitaria, Coyoacán 04510 Ciudad de
México, México
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11
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Blunsom NJ, Gomez-Espinosa E, Ashlin TG, Cockcroft S. Sustained phospholipase C stimulation of H9c2 cardiomyoblasts by vasopressin induces an increase in CDP-diacylglycerol synthase 1 (CDS1) through protein kinase C and cFos. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1864:1072-1082. [PMID: 30862571 PMCID: PMC6495107 DOI: 10.1016/j.bbalip.2019.03.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 02/28/2019] [Accepted: 03/06/2019] [Indexed: 01/18/2023]
Abstract
Chronic stimulation (24 h) with vasopressin leads to hypertrophy in H9c2 cardiomyoblasts and this is accompanied by continuous activation of phospholipase C. Consequently, vasopressin stimulation leads to a depletion of phosphatidylinositol levels. The substrate for phospholipase C is phosphatidylinositol (4, 5) bisphosphate (PIP2) and resynthesis of phosphatidylinositol and its subsequent phosphorylation maintains the supply of PIP2. The resynthesis of PI requires the conversion of phosphatidic acid to CDP-diacylglycerol catalysed by CDP-diacylglycerol synthase (CDS) enzymes. To examine whether the resynthesis of PI is regulated by vasopressin stimulation, we focussed on the CDS enzymes. Three CDS enzymes are present in mammalian cells: CDS1 and CDS2 are integral membrane proteins localised at the endoplasmic reticulum and TAMM41 is a peripheral protein localised in the mitochondria. Vasopressin selectively stimulates an increase CDS1 mRNA that is dependent on protein kinase C, and can be inhibited by the AP-1 inhibitor, T-5224. Vasopressin also stimulates an increase in cFos protein which is inhibited by a protein kinase C inhibitor. We conclude that vasopressin stimulates CDS1 mRNA through phospholipase C, protein kinase C and cFos and provides a potential mechanism for maintenance of phosphatidylinositol levels during long-term phospholipase C signalling.
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Affiliation(s)
- Nicholas J Blunsom
- Dept. of Neuroscience, Physiology and Pharmacology, Division of Biosciences, University College London, London WC1E 6JJ, UK
| | - Evelyn Gomez-Espinosa
- Dept. of Neuroscience, Physiology and Pharmacology, Division of Biosciences, University College London, London WC1E 6JJ, UK
| | - Tim G Ashlin
- Dept. of Neuroscience, Physiology and Pharmacology, Division of Biosciences, University College London, London WC1E 6JJ, UK
| | - Shamshad Cockcroft
- Dept. of Neuroscience, Physiology and Pharmacology, Division of Biosciences, University College London, London WC1E 6JJ, UK.
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12
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Wehrle A, Witkos TM, Unger S, Schneider J, Follit JA, Hermann J, Welting T, Fano V, Hietala M, Vatanavicharn N, Schoner K, Spranger J, Schmidts M, Zabel B, Pazour GJ, Bloch-Zupan A, Nishimura G, Superti-Furga A, Lowe M, Lausch E. Hypomorphic mutations of TRIP11 cause odontochondrodysplasia. JCI Insight 2019; 4:124701. [PMID: 30728324 PMCID: PMC6413787 DOI: 10.1172/jci.insight.124701] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 12/20/2018] [Indexed: 12/24/2022] Open
Abstract
Odontochondrodysplasia (ODCD) is an unresolved genetic disorder of skeletal and dental development. Here, we show that ODCD is caused by hypomorphic TRIP11 mutations, and we identify ODCD as the nonlethal counterpart to achondrogenesis 1A (ACG1A), the known null phenotype in humans. TRIP11 encodes Golgi-associated microtubule-binding protein 210 (GMAP-210), an essential tether protein of the Golgi apparatus that physically interacts with intraflagellar transport 20 (IFT20), a component of the ciliary intraflagellar transport complex B. This association and extraskeletal disease manifestations in ODCD point to a cilium-dependent pathogenesis. However, our functional studies in patient-derived primary cells clearly support a Golgi-based disease mechanism. In spite of reduced abundance, residual GMAP variants maintain partial Golgi integrity, normal global protein secretion, and subcellular distribution of IFT20 in ODCD. These functions are lost when GMAP-210 is completely abrogated in ACG1A. However, a similar defect in chondrocyte maturation is observed in both disorders, which produces a cellular achondrogenesis phenotype of different severity, ensuing from aberrant glycan processing and impaired extracellular matrix proteoglycan secretion by the Golgi apparatus. Bi-allelic mutations of TRIP11 cause a spectrum of skeletal phenotypes whose severity is primarily based on impaired secretory trafficking and aberrant glycan processing.
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Affiliation(s)
- Anika Wehrle
- Department of Pediatrics, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Tomasz M Witkos
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Sheila Unger
- Division of Genetic Medicine, University of Lausanne, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Judith Schneider
- Department of Pediatrics, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - John A Follit
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Johannes Hermann
- Department of Pediatrics, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Tim Welting
- Laboratory for Experimental Orthopedics, Department of Orthopaedic Surgery, Maastricht University Medical Centre, Maastricht, the Netherlands
| | - Virginia Fano
- Hospital de Pediatria JP Garrahan, Buenos Aires, Argentina
| | - Marja Hietala
- Medical Biochemistry and Genetics, University of Turku, Turku, Finland
| | | | - Katharina Schoner
- Institute of Pathology, Philipps-University Marburg, Marburg, Germany
| | - Jürgen Spranger
- Department of Pediatrics, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Miriam Schmidts
- Department of Pediatrics, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Bernhard Zabel
- Department of Pediatrics, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Gregory J Pazour
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, USA
| | - Agnes Bloch-Zupan
- Centre de Référence des Manifestations Odontologiques des Maladies Rares, Pôle de Médecine et Chirurgie Bucco-dentaires, Hôpitaux Universitaires de Strasbourg (HUS), Faculté de Chirurgie Dentaire, Université de Strasbourg, Strasbourg, France.,Université de Strasbourg, Faculté de Chirurgie Dentaire, Institute of Advanced Studies, USIAS, Strasbourg, France.,HUS, Pôle de Médecine et Chirurgie Bucco-dentaires Hôpital Civil, Centre de référence des maladies rares orales et dentaires, O-Rares, Filière Santé Maladies rares TETE COU, European Reference Network ERN CRANIO, Strasbourg, France.,Université de Strasbourg, Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), CERBM, INSERM U1258, CNRS- UMR7104, Illkirch, France
| | - Gen Nishimura
- Department of Radiology and Medical Imaging, Tokyo Metropolitan Kiyose Children's Hospital, Kiyose, Japan
| | - Andrea Superti-Furga
- Division of Genetic Medicine, University of Lausanne, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Martin Lowe
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Ekkehart Lausch
- Department of Pediatrics, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
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13
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Abstract
The Golgi apparatus is a central intracellular membrane-bound organelle with key functions in trafficking, processing, and sorting of newly synthesized membrane and secretory proteins and lipids. To best perform these functions, Golgi membranes form a unique stacked structure. The Golgi structure is dynamic but tightly regulated; it undergoes rapid disassembly and reassembly during the cell cycle of mammalian cells and is disrupted under certain stress and pathological conditions. In the past decade, significant amount of effort has been made to reveal the molecular mechanisms that regulate the Golgi membrane architecture and function. Here we review the major discoveries in the mechanisms of Golgi structure formation, regulation, and alteration in relation to its functions in physiological and pathological conditions to further our understanding of Golgi structure and function in health and diseases.
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Affiliation(s)
- Jie Li
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Erpan Ahat
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Yanzhuang Wang
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, MI, USA.
- Department of Neurology, University of Michigan School of Medicine, Ann Arbor, MI, USA.
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14
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Wehrle A, Witkos TM, Schneider JC, Hoppmann A, Behringer S, Köttgen A, Elting M, Spranger J, Lowe M, Lausch E. A common pathomechanism in GMAP-210- and LBR-related diseases. JCI Insight 2018; 3:121150. [PMID: 30518689 PMCID: PMC6328090 DOI: 10.1172/jci.insight.121150] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 10/29/2018] [Indexed: 12/20/2022] Open
Abstract
Biallelic loss-of-function mutations in TRIP11, encoding the golgin GMAP-210, cause the lethal human chondrodysplasia achondrogenesis 1A (ACG1A). We now find that a homozygous splice-site mutation of the lamin B receptor (LBR) gene results in the same phenotype. Intrigued by the genetic heterogeneity, we compared GMAP-210- and LBR-deficient primary cells to unravel how particular mutations in LBR cause a phenocopy of ACG1A. We could exclude a regulatory interaction between LBR and GMAP-210 in patients' cells. However, we discovered a common disruption of Golgi apparatus architecture that was accompanied by decreased secretory trafficking in both cases. Deficiency of Golgi-dependent glycan processing indicated a similar downstream effect of the disease-causing mutations upon Golgi function. Unexpectedly, our results thus point to a common pathogenic mechanism in GMAP-210- and LBR-related diseases attributable to defective secretory trafficking at the Golgi apparatus.
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Affiliation(s)
- Anika Wehrle
- Department of Pediatrics, Medical Centre-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Tomasz M. Witkos
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Judith C. Schneider
- Department of Pediatrics, Medical Centre-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Anselm Hoppmann
- Department of Pediatrics, Medical Centre-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
- Institute of Genetic Epidemiology, Medical Centre-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Sidney Behringer
- Department of Pediatrics, Medical Centre-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Anna Köttgen
- Institute of Genetic Epidemiology, Medical Centre-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Mariet Elting
- Department of Clinical Genetics, VU University Medical Center, Amsterdam, Netherlands
| | - Jürgen Spranger
- Department of Pediatrics, Medical Centre-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Martin Lowe
- Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Ekkehart Lausch
- Department of Pediatrics, Medical Centre-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
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15
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RING domain of zinc finger protein like 1 is essential for cell proliferation in endometrial cancer cell line RL95-2. Gene 2018; 677:17-23. [DOI: 10.1016/j.gene.2018.07.053] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 07/10/2018] [Accepted: 07/19/2018] [Indexed: 01/31/2023]
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16
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Papillomaviruses and Endocytic Trafficking. Int J Mol Sci 2018; 19:ijms19092619. [PMID: 30181457 PMCID: PMC6163501 DOI: 10.3390/ijms19092619] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Revised: 08/24/2018] [Accepted: 08/29/2018] [Indexed: 12/14/2022] Open
Abstract
Endocytic trafficking plays a major role in transport of incoming human papillomavirus (HPVs) from plasma membrane to the trans Golgi network (TGN) and ultimately into the nucleus. During this infectious entry, several cellular sorting factors are recruited by the viral capsid protein L2, which plays a critical role in ensuring successful transport of the L2/viral DNA complex to the nucleus. Later in the infection cycle, two viral oncoproteins, E5 and E6, have also been shown to modulate different aspects of endocytic transport pathways. In this review, we highlight how HPV makes use of and perturbs normal endocytic transport pathways, firstly to achieve infectious virus entry, secondly to produce productive infection and the completion of the viral life cycle and, finally, on rare occasions, to bring about the development of malignancy.
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17
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Barlow LD, Nývltová E, Aguilar M, Tachezy J, Dacks JB. A sophisticated, differentiated Golgi in the ancestor of eukaryotes. BMC Biol 2018; 16:27. [PMID: 29510703 PMCID: PMC5840792 DOI: 10.1186/s12915-018-0492-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2017] [Accepted: 01/25/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The Golgi apparatus is a central meeting point for the endocytic and exocytic systems in eukaryotic cells, and the organelle's dysfunction results in human disease. Its characteristic morphology of multiple differentiated compartments organized into stacked flattened cisternae is one of the most recognizable features of modern eukaryotic cells, and yet how this is maintained is not well understood. The Golgi is also an ancient aspect of eukaryotes, but the extent and nature of its complexity in the ancestor of eukaryotes is unclear. Various proteins have roles in organizing the Golgi, chief among them being the golgins. RESULTS We address Golgi evolution by analyzing genome sequences from organisms which have lost stacked cisternae as a feature of their Golgi and those that have not. Using genomics and immunomicroscopy, we first identify Golgi in the anaerobic amoeba Mastigamoeba balamuthi. We then searched 87 genomes spanning eukaryotic diversity for presence of the most prominent proteins implicated in Golgi structure, focusing on golgins. We show some candidates as animal specific and others as ancestral to eukaryotes. CONCLUSIONS None of the proteins examined show a phyletic distribution that correlates with the morphology of stacked cisternae, suggesting the possibility of stacking as an emergent property. Strikingly, however, the combination of golgins conserved among diverse eukaryotes allows for the most detailed reconstruction of the organelle to date, showing a sophisticated Golgi with differentiated compartments and trafficking pathways in the common eukaryotic ancestor.
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Affiliation(s)
- Lael D Barlow
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, 5-31 Medical Sciences Building, Edmonton, Alberta, T6G 2H7, Canada
| | - Eva Nývltová
- Department of Parasitology (BIOCEV), Faculty of Science, Charles University, Průmyslová 595, 252 42, Vestec, Czech Republic.,Department of Neurology, University of Miami Miller School of Medicine, 1600 NW 10th Avenue, Rosenstiel Medical Science Building (RMSB) # 2067, Miami, Florida, 33136, USA
| | - Maria Aguilar
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, 5-31 Medical Sciences Building, Edmonton, Alberta, T6G 2H7, Canada
| | - Jan Tachezy
- Department of Parasitology (BIOCEV), Faculty of Science, Charles University, Průmyslová 595, 252 42, Vestec, Czech Republic
| | - Joel B Dacks
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, 5-31 Medical Sciences Building, Edmonton, Alberta, T6G 2H7, Canada. .,Department of Life Sciences, The Natural History Museum, Cromwell Road, London, SW7 5BD, UK.
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18
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Xie YZ, Ma WL, Meng JM, Ren XQ. Knockdown of ZFPL1 results in increased autophagy and autophagy‑related cell death in NCI‑N87 and BGC‑823 human gastric carcinoma cell lines. Mol Med Rep 2017; 15:2633-2642. [PMID: 28447717 DOI: 10.3892/mmr.2017.6300] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 09/28/2016] [Indexed: 11/06/2022] Open
Abstract
Macroautophagy, which will hereafter be referred to as autophagy, is an evolutionarily conserved process, during which cells recycle and remove damaged organelles and proteins in response to cellular stress. However, the mechanisms underlying the regulation of autophagy remain to be fully elucidated. The present study demonstrated that knockdown of zinc finger protein like 1 (ZFPL1) induces autophagy and increases autophagic cell death in NCI‑N87 and BGC‑823 human gastric carcinoma cell lines. To examine the role of ZFPL1 in gastric carcinoma cells, ZFPL1 expression was downregulated by lentiviral infection. Zinc finger domain‑FLAG was used to compete with ZFPL1 for golgin A2/GM130 binding. Autophagy was analyzed by red fluorescent protein‑microtubule‑associated protein 1A/1B‑light chain 3 (LC3) puncta, LC3I to LC3II conversion, and p62 expression. The results demonstrated that knockdown of ZFPL1 was able to significantly increase cell death rate. However, ZFPL1 knockdown exerted almost no effect on the expression of apoptosis‑associated markers, including B cell lymphoma 2 (Bcl‑2), Bcl‑x, Bcl‑2‑associated X protein, BH3 interacting domain death agonist, p53, and the classical caspase family members, caspase‑3, caspase‑8 and caspase‑9. An endogenous ZFPL1‑GM130 association was identified in NCI‑N87 cells and BGC‑823 cells by co‑immunoprecipitation. Furthermore, cell death was restricted following treatment of ZFPL1 knockdown cells with an autophagy inhibitor. Therefore, knockdown of ZFPL1 expression may induce cell death via autophagy, rather than apoptosis. These results suggest that ZFPL1 may serve an important role in regulating autophagy in NCI‑N87 and BGC‑823 cells.
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Affiliation(s)
- Yong-Zheng Xie
- Department of General Surgery, Huaihe Hospital of Henan University, Kaifeng, Henan 475000, P.R. China
| | - Wan-Li Ma
- Department of General Surgery, Huaihe Hospital of Henan University, Kaifeng, Henan 475000, P.R. China
| | - Ji-Ming Meng
- Department of General Surgery, Huaihe Hospital of Henan University, Kaifeng, Henan 475000, P.R. China
| | - Xue-Qun Ren
- Department of General Surgery, Huaihe Hospital of Henan University, Kaifeng, Henan 475000, P.R. China
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19
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Wong M, Gillingham AK, Munro S. The golgin coiled-coil proteins capture different types of transport carriers via distinct N-terminal motifs. BMC Biol 2017; 15:3. [PMID: 28122620 PMCID: PMC5267433 DOI: 10.1186/s12915-016-0345-3] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Accepted: 12/21/2016] [Indexed: 12/13/2022] Open
Abstract
Background The internal organization of cells depends on mechanisms to ensure that transport carriers, such as vesicles, fuse only with the correct destination organelle. Several types of proteins have been proposed to confer specificity to this process, and we have recently shown that a set of coiled-coil proteins on the Golgi, called golgins, are able to capture specific classes of carriers when relocated to an ectopic location. Results Mapping of six different golgins reveals that, in each case, a short 20–50 residue region is necessary and sufficient to capture specific carriers. In all six of GMAP-210, golgin-84, TMF, golgin-97, golgin-245, and GCC88, this region is located at the extreme N-terminus of the protein. The vesicle-capturing regions of GMAP-210, golgin-84, and TMF capture intra-Golgi vesicles and share some sequence features, suggesting that they act in a related, if distinct, manner. In the case of GMAP-210, this shared feature is in addition to a previously characterized “amphipathic lipid-packing sensor” motif that can capture highly curved membranes, with the two motifs being apparently involved in capturing distinct types of vesicles. Of the three GRIP domain golgins that capture endosome-to-Golgi carriers, golgin-97 and golgin-245 share a closely related capture motif, whereas that in GCC88 is distinct, suggesting that it works by a different mechanism and raising the possibility that the three golgins capture different classes of endosome-derived carriers that share many cargos but have distinct features for recognition at the Golgi. Conclusions For six different golgins, the capture of carriers is mediated by a short region at the N-terminus of the protein. There appear to be at least four different types of motif, consistent with specific golgins capturing specific classes of carrier and implying the existence of distinct receptors present on each of these different carrier classes.
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Affiliation(s)
- Mie Wong
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Alison K Gillingham
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK
| | - Sean Munro
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge, CB2 0QH, UK.
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20
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Wong M, Munro S. Membrane trafficking. The specificity of vesicle traffic to the Golgi is encoded in the golgin coiled-coil proteins. Science 2014; 346:1256898. [PMID: 25359980 DOI: 10.1126/science.1256898] [Citation(s) in RCA: 192] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The Golgi apparatus is a multicompartment central sorting station at the intersection of secretory and endocytic vesicular traffic. The mechanisms that permit cargo-loaded transport vesicles from different origins to selectively access different Golgi compartments are incompletely understood. We developed a rerouting and capture assay to investigate systematically the vesicle-tethering activities of 10 widely conserved golgin coiled-coil proteins. We find that subsets of golgins with distinct localizations on the Golgi surface have capture activities toward vesicles of different origins. These findings demonstrate that golgins act as tethers in vivo, and hence the specificity we find to be encoded in this tethering is likely to make a major contribution to the organization of membrane traffic at the Golgi apparatus.
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Affiliation(s)
- Mie Wong
- MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
| | - Sean Munro
- MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK.
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21
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Ahmedli NB, Gribanova Y, Njoku CC, Naidu A, Young A, Mendoza E, Yamashita CK, Özgül RK, Johnson JE, Fox DA, Farber DB. Dynamics of the rhomboid-like protein RHBDD2 expression in mouse retina and involvement of its human ortholog in retinitis pigmentosa. J Biol Chem 2013; 288:9742-9754. [PMID: 23386608 DOI: 10.1074/jbc.m112.419960] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The novel rhomboid-like protein RHBDD2 is distantly related to rhomboid proteins, a group of highly specialized membrane-bound proteases that catalyze regulated intramembrane proteolysis. In retina, RHBDD2 is expressed from embryonic stages to adulthood, and its levels show age-dependent changes. RHBDD2 is distinctly abundant in the perinuclear region of cells, and it localizes to their Golgi. A glycine zipper motif present in one of the transmembrane domains of RHBDD2 is important for its packing into the Golgi membranes. Its deletion causes dislodgment of RHBDD2 from the Golgi. A specific antibody against RHBDD2 recognizes two forms of the protein, one with low (39 kDa; RHBDD2(L)) and the other with high (117 kDa; RHBDD2H) molecular masses in mouse retinal extracts. RHBDD2(L) seems to be ubiquitously expressed in all retinal cells. In contrast, RHBDD2H seems to be present only in the outer segments of cone photoreceptors and may correspond to a homotrimer of RHBDD2(L). This protein consistently co-localizes with S- and M-types of cone opsins. We identified a homozygous mutation in the human RHBDD2 gene, R85H, that co-segregates with disease in affected members of a family with autosomal recessive retinitis pigmentosa. Our findings suggest that the RHBDD2 protein plays important roles in the development and normal function of the retina.
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Affiliation(s)
| | | | - Collins C Njoku
- Jules Stein Eye Institute, UCLA, Los Angeles, California 90095
| | - Akash Naidu
- Jules Stein Eye Institute, UCLA, Los Angeles, California 90095
| | - Alejandra Young
- Jules Stein Eye Institute, UCLA, Los Angeles, California 90095
| | | | | | - Riza Köksal Özgül
- Department of Molecular Biology, Hacettepe University, 06230 Beytepe-Ankara, Turkey
| | - Jerry E Johnson
- Department of Natural Sciences, University of Houston-Downtown, Houston, Texas 77002
| | - Donald A Fox
- College of Optometry, University of Houston, Houston, Texas 77004; Department of Biology and Biochemistry, University of Houston, Houston, Texas 77004; Department of Pharmacology and Pharmaceutical Sciences, University of Houston, Houston, Texas 77004
| | - Debora B Farber
- Jules Stein Eye Institute, UCLA, Los Angeles, California 90095; Molecular Biology Institute, UCLA, Los Angeles, California 90095; Brain Research Institute, UCLA, Los Angeles, California 90095
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22
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Xu J, Tian H, Wang W, Liang A. The zinc finger protein Zfr1p is localized specifically to conjugation junction and required for sexual development in Tetrahymena thermophila. PLoS One 2012; 7:e52799. [PMID: 23251712 PMCID: PMC3519685 DOI: 10.1371/journal.pone.0052799] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Accepted: 11/21/2012] [Indexed: 11/19/2022] Open
Abstract
Conjugation in Tetrahymena thermophila involves a developmental program consisting of three prezygotic nuclear divisions, pronuclear exchange and fusion, and postzygotic and exconjugant stages. The conjugation junction structure appears during the initiation of conjugation development, and disappears during the exconjugant stage. Many structural and functional proteins are involved in the establishment and maintenance of the junction structure in T. thermophila. In the present study, a zinc finger protein-encoding gene ZFR1 was found to be expressed specifically during conjugation and to localize specifically to the conjugation junction region. Truncated Zfr1p localized at the plasma membrane in ordered arrays and decorated Golgi apparatus located adjacent to basal body. The N-terminal zinc finger and C-terminal hydrophobic domains of Zfr1p were found to be required for its specific conjugation junction localization. Conjugation development of ZFR1 somatic knockout cells was aborted at the pronuclear exchange and fusion conjugation stages. Furthermore, Zfr1p was found to be important for conjugation junction stability during the prezygotic nuclear division stage. Taken together, our data reveal that Zfr1p is required for the stability and integrity of the conjugation junction structure and essential for the sexual life cycle of the Tetrahymena cell.
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Affiliation(s)
- Jing Xu
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan, China
| | - Huaru Tian
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan, China
| | - Wei Wang
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan, China
| | - Aihua Liang
- Key Laboratory of Chemical Biology and Molecular Engineering of Ministry of Education, Institute of Biotechnology, Shanxi University, Taiyuan, China
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23
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Abstract
As plant Golgi bodies move through the cell along the actin cytoskeleton, they face the need to maintain their polarized stack structure whilst receiving, processing and distributing protein cargo destined for secretion. Structural proteins, or Golgi matrix proteins, help to hold cisternae together and tethering factors direct cargo carriers to the correct target membranes. This review focuses on golgins, a protein family containing long coiled-coil regions, summarizes their known functions in animal cells and highlights recent findings about plant golgins and their putative roles in the plant secretory pathway.
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Affiliation(s)
- A Osterrieder
- Department of Biological and Medical Sciences, Faculty of Health and Life Sciences, Oxford Brookes University, Oxford, UK.
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Nakamura N. The Role of the Transmembrane RING Finger Proteins in Cellular and Organelle Function. MEMBRANES 2011; 1:354-93. [PMID: 24957874 PMCID: PMC4021871 DOI: 10.3390/membranes1040354] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/26/2011] [Revised: 11/24/2011] [Accepted: 12/05/2011] [Indexed: 01/08/2023]
Abstract
A large number of RING finger (RNF) proteins are present in eukaryotic cells and the majority of them are believed to act as E3 ubiquitin ligases. In humans, 49 RNF proteins are predicted to contain transmembrane domains, several of which are specifically localized to membrane compartments in the secretory and endocytic pathways, as well as to mitochondria and peroxisomes. They are thought to be molecular regulators of the organization and integrity of the functions and dynamic architecture of cellular membrane and membranous organelles. Emerging evidence has suggested that transmembrane RNF proteins control the stability, trafficking and activity of proteins that are involved in many aspects of cellular and physiological processes. This review summarizes the current knowledge of mammalian transmembrane RNF proteins, focusing on their roles and significance.
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Affiliation(s)
- Nobuhiro Nakamura
- Department of Biological Sciences, Tokyo Institute of Technology, 4259-B13 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan.
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Aletrari MO, McKibbin C, Williams H, Pawar V, Pietroni P, Lord JM, Flitsch SL, Whitehead R, Swanton E, High S, Spooner RA. Eeyarestatin 1 interferes with both retrograde and anterograde intracellular trafficking pathways. PLoS One 2011; 6:e22713. [PMID: 21799938 PMCID: PMC3143184 DOI: 10.1371/journal.pone.0022713] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2011] [Accepted: 06/28/2011] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND The small molecule Eeyarestatin I (ESI) inhibits the endoplasmic reticulum (ER)-cytosol dislocation and subsequent degradation of ERAD (ER associated protein degradation) substrates. Toxins such as ricin and Shiga/Shiga-like toxins (SLTx) are endocytosed and trafficked to the ER. Their catalytic subunits are thought to utilise ERAD-like mechanisms to dislocate from the ER into the cytosol, where a proportion uncouples from the ERAD process, recovers a catalytic conformation and destroys their cellular targets. We therefore investigated ESI as a potential inhibitor of toxin dislocation. METHODOLOGY AND PRINCIPAL FINDINGS Using cytotoxicity measurements, we found no role for ES(I) as an inhibitor of toxin dislocation from the ER, but instead found that for SLTx, ESI treatment of cells was protective by reducing the rate of toxin delivery to the ER. Microscopy of the trafficking of labelled SLTx and its B chain (lacking the toxic A chain) showed a delay in its accumulation at a peri-nuclear location, confirmed to be the Golgi by examination of SLTx B chain metabolically labelled in the trans-Golgi cisternae. The drug also reduced the rate of endosomal trafficking of diphtheria toxin, which enters the cytosol from acidified endosomes, and delayed the Golgi-specific glycan modifications and eventual plasma membrane appearance of tsO45 VSV-G protein, a classical marker for anterograde trafficking. CONCLUSIONS AND SIGNIFICANCE ESI acts on one or more components that function during vesicular transport, whilst at least one retrograde trafficking pathway, that of ricin, remains unperturbed.
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Affiliation(s)
- Mina-Olga Aletrari
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Craig McKibbin
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | - Helen Williams
- School of Chemistry, University of Manchester, Manchester, United Kingdom
| | - Vidya Pawar
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Paola Pietroni
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - J. Michael Lord
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
| | - Sabine L. Flitsch
- School of Chemistry, University of Manchester, Manchester, United Kingdom
- Manchester Interdisciplinary Biocentre, University of Manchester, Manchester, United Kingdom
| | - Roger Whitehead
- School of Chemistry, University of Manchester, Manchester, United Kingdom
| | - Eileithyia Swanton
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | - Stephen High
- Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
- * E-mail: (RAS); (SH)
| | - Robert A. Spooner
- School of Life Sciences, University of Warwick, Coventry, United Kingdom
- * E-mail: (RAS); (SH)
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Vitry S, Bruyère J, Hocquemiller M, Bigou S, Ausseil J, Colle MA, Prévost MC, Heard JM. Storage vesicles in neurons are related to Golgi complex alterations in mucopolysaccharidosis IIIB. THE AMERICAN JOURNAL OF PATHOLOGY 2010; 177:2984-99. [PMID: 21037080 DOI: 10.2353/ajpath.2010.100447] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The accumulation of intracellular storage vesicles is a hallmark of lysosomal storage diseases. Neither the identity nor origin of these implicated storage vesicles have yet been established. The vesicles are often considered as lysosomes, endosomes, and/or autophagosomes that are engorged with undigested materials. Our studies in the mouse model of mucopolysaccharidosis type IIIB, a lysosomal storage disease that induces neurodegeneration, showed that large storage vesicles in cortical neurons did not receive material from either the endocytic or autophagy pathway, which functioned normally. Storage vesicles expressed GM130, a Golgi matrix protein, which mediates vesicle tethering in both pre- and cis-Golgi compartments. However, other components of the tethering/fusion complex were not associated with GM130 on storage vesicles, likely accounting for both the resistance of the vesicles to brefeldin A and the alteration of Golgi ribbon architecture, which comprised distended cisterna connected to LAMP1-positive storage vesicles. We propose that alteration in the GM130-mediated control of vesicle trafficking in pre-Golgi and Golgi compartments affects Golgi biogenesis and gives rise to a dead-end storage compartment. Vesicle accumulation, Golgi disorganization, and alterations of other GM130 functions may account for neuron dysfunction and death.
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Affiliation(s)
- Sandrine Vitry
- Unité Rétrovirus et Transfert Génétique, INSERM U622, Department of Neuroscience, Institut Pasteur 28 rue du Dr Roux, 75015 Paris, France
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27
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Phosphorylation and membrane dissociation of the ARF exchange factor GBF1 in mitosis. Biochem J 2010; 427:401-12. [PMID: 20175751 DOI: 10.1042/bj20091681] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Secretory protein trafficking is arrested and the Golgi apparatus fragmented when mammalian cells enter mitosis. These changes are thought to facilitate cell-cycle progression and Golgi inheritance, and are brought about through the actions of mitotically active protein kinases. To better understand how the Golgi apparatus undergoes mitotic fragmentation we have sought to identify novel Golgi targets for mitotic kinases. We report in the present paper the identification of the ARF (ADP-ribosylation factor) exchange factor GBF1 (Golgi-specific brefeldin A-resistant guanine nucleotide-exchange factor 1) as a Golgi phosphoprotein. GBF1 is phosphorylated by CDK1 (cyclin-dependent kinase 1)-cyclin B in mitosis, which results in its dissociation from Golgi membranes. Consistent with a reduced level of GBF1 activity at the Golgi membrane there is a reduction in levels of membrane-associated GTP-bound ARF in mitotic cells. Despite the reduced levels of membrane-bound GBF1 and ARF, COPI (coat protein I) binding to the Golgi membrane appears unaffected in mitotic cells. Surprisingly, this pool of COPI is dependent upon GBF1 for its recruitment to the membrane, suggesting that a low level of GBF1 activity persists in mitosis. We propose that the phosphorylation and membrane dissociation of GBF1 and the consequent reduction in ARF-GTP levels in mitosis are important for changes in Golgi dynamics and possibly other mitotic events mediated through effectors other than the COPI vesicle coat.
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28
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Golgins and GRASPs: holding the Golgi together. Semin Cell Dev Biol 2009; 20:770-9. [PMID: 19508854 DOI: 10.1016/j.semcdb.2009.03.011] [Citation(s) in RCA: 111] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2009] [Revised: 03/16/2009] [Accepted: 03/17/2009] [Indexed: 12/28/2022]
Abstract
The GRASP and golgin families of proteins have emerged as key components of the Golgi apparatus, with major roles in both the structural organisation of this organelle and the trafficking that occurs there. Both types of protein participate in membrane tethering events that occur upstream of membrane fusion as well as contributing to the structural scaffold that defines Golgi architecture, referred to as the Golgi matrix. The importance of these proteins is highlighted by their targeting in mitosis, apoptosis, and pathogenic infections that cause dramatic structural and functional reorganisation of the Golgi apparatus. In this review we will discuss our current understanding of GRASP and golgin function, highlighting some of the common themes that have emerged as well as describing previously unsuspected roles for these proteins in various cellular processes.
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Sztul E, Lupashin V. Role of vesicle tethering factors in the ER-Golgi membrane traffic. FEBS Lett 2009; 583:3770-83. [PMID: 19887069 DOI: 10.1016/j.febslet.2009.10.083] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2009] [Revised: 10/29/2009] [Accepted: 10/30/2009] [Indexed: 12/27/2022]
Abstract
Tethers are a diverse group of loosely related proteins and protein complexes grouped into three families based on structural and functional similarities. A well-accepted role for tethering factors is the initial attachment of transport carriers to acceptor membranes prior to fusion. However, accumulating evidence indicates that tethers are more than static bridges. Tethers have been shown to interact with components of the fusion machinery and with components involved in vesicle formation. Tethers belonging to the three families act at the same stage of traffic, suggesting that they mediate distinct events during vesicle tethering. Thus, multiple tether-facilitated events are required to provide selectivity to vesicle fusion. In this review, we highlight findings that support this model.
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Affiliation(s)
- Elizabeth Sztul
- Department of Cell Biology, University of Alabama at Birmingham, 1918 University Boulevard, Birmingham, AL 35294, USA
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Palmer KJ, Hughes H, Stephens DJ. Specificity of cytoplasmic dynein subunits in discrete membrane-trafficking steps. Mol Biol Cell 2009; 20:2885-99. [PMID: 19386764 DOI: 10.1091/mbc.e08-12-1160] [Citation(s) in RCA: 101] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The cytoplasmic dynein motor complex is known to exist in multiple forms, but few specific functions have been assigned to individual subunits. A key limitation in the analysis of dynein in intact mammalian cells has been the reliance on gross perturbation of dynein function, e.g., inhibitory antibodies, depolymerization of the entire microtubule network, or the use of expression of dominant negative proteins that inhibit dynein indirectly. Here, we have used RNAi and automated image analysis to define roles for dynein subunits in distinct membrane-trafficking processes. Depletion of a specific subset of dynein subunits, notably LIC1 (DYNC1LI1) but not LIC2 (DYNC1LI2), recapitulates a direct block of ER export, revealing that dynein is required to maintain the steady-state composition of the Golgi, through ongoing ER-to-Golgi transport. Suppression of LIC2 but not of LIC1 results in a defect in recycling endosome distribution and cytokinesis. Biochemical analyses also define the role of each subunit in stabilization of the dynein complex; notably, suppression of DHC1 or IC2 results in concomitant loss of Tctex1. Our data demonstrate that LIC1 and LIC2 define distinct dynein complexes that function at the Golgi versus recycling endosomes, respectively, suggesting that functional populations of dynein mediate discrete intracellular trafficking pathways.
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Affiliation(s)
- Krysten J Palmer
- Cell Biology Laboratories, Department of Biochemistry, School of Medical Sciences, University of Bristol, Bristol BS81TD, United Kingdom
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