1
|
Chua SCJH, Cui J, Sachaphibulkij K, Tan ISL, Tan HQ, Lim HM, Engelberg D, Lim LHK. The ER-Golgi transport of influenza virus through NS1-Sec13 association during virus replication. Microbiol Spectr 2024; 12:e0260923. [PMID: 38038453 PMCID: PMC10782970 DOI: 10.1128/spectrum.02609-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 10/30/2023] [Indexed: 12/02/2023] Open
Abstract
IMPORTANCE Influenza A virus is a respiratory virus that can cause complications such as acute bronchitis and secondary bacterial pneumonia. Drug therapies and vaccines are available against influenza, albeit limited by drug resistance and the non-universal vaccine administration. Hence there is a need for host-targeted therapies against influenza to provide an effective alternative therapeutic target. Sec13 was identified as a novel host interactor of influenza. Endoplasmic reticulum-to-Golgi transport is an important pathway of influenza virus replication and viral export. Specifically, Sec13 has a functional role in influenza replication and virulence.
Collapse
Affiliation(s)
- Sonja C. J. H. Chua
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- NUS Immunology Program, Life Sciences Institute, National University of Singapore, Singapore, Singapore
- NUSMED Immunology Translational Research Programme, National University of Singapore, Singapore, Singapore
- CREATE-NUS-HUJ Molecular Mechanisms of Inflammatory Diseases Programme, National University of Singapore, Singapore, Singapore
- Department of Biological Chemistry, The Institute of Life Science, The Hebrew University of Jerusalem, Jerusalem, Israel
| | - Jianzhou Cui
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- NUS Immunology Program, Life Sciences Institute, National University of Singapore, Singapore, Singapore
- NUSMED Immunology Translational Research Programme, National University of Singapore, Singapore, Singapore
| | - Karishma Sachaphibulkij
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- NUS Immunology Program, Life Sciences Institute, National University of Singapore, Singapore, Singapore
- NUSMED Immunology Translational Research Programme, National University of Singapore, Singapore, Singapore
| | - Isabelle Siang Ling Tan
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- NUS Immunology Program, Life Sciences Institute, National University of Singapore, Singapore, Singapore
- NUSMED Immunology Translational Research Programme, National University of Singapore, Singapore, Singapore
| | - Hui Qing Tan
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- NUS Immunology Program, Life Sciences Institute, National University of Singapore, Singapore, Singapore
- NUSMED Immunology Translational Research Programme, National University of Singapore, Singapore, Singapore
| | - Hong Meng Lim
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- NUS Immunology Program, Life Sciences Institute, National University of Singapore, Singapore, Singapore
- NUSMED Immunology Translational Research Programme, National University of Singapore, Singapore, Singapore
| | - David Engelberg
- CREATE-NUS-HUJ Molecular Mechanisms of Inflammatory Diseases Programme, National University of Singapore, Singapore, Singapore
- Department of Biological Chemistry, The Institute of Life Science, The Hebrew University of Jerusalem, Jerusalem, Israel
- Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Lina H. K. Lim
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
- NUS Immunology Program, Life Sciences Institute, National University of Singapore, Singapore, Singapore
- NUSMED Immunology Translational Research Programme, National University of Singapore, Singapore, Singapore
| |
Collapse
|
2
|
Tang VT, Ginsburg D. Cargo selection in endoplasmic reticulum-to-Golgi transport and relevant diseases. J Clin Invest 2023; 133:163838. [PMID: 36594468 PMCID: PMC9797344 DOI: 10.1172/jci163838] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Most proteins destined for the extracellular space or various intracellular compartments must traverse the intracellular secretory pathway. The first step is the recruitment and transport of cargoes from the endoplasmic reticulum (ER) lumen to the Golgi apparatus by coat protein complex II (COPII), consisting of five core proteins. Additional ER transmembrane proteins that aid cargo recruitment are referred to as cargo receptors. Gene duplication events have resulted in multiple COPII paralogs present in the mammalian genome. Here, we review the functions of each COPII protein, human disorders associated with each paralog, and evidence for functional conservation between paralogs. We also provide a summary of current knowledge regarding two prototypical cargo receptors in mammals, LMAN1 and SURF4, and their roles in human health and disease.
Collapse
Affiliation(s)
- Vi T. Tang
- Department of Molecular and Integrative Physiology,,Life Sciences Institute
| | - David Ginsburg
- Life Sciences Institute,,Department of Internal Medicine,,Department of Human Genetics,,Department of Pediatrics and Communicable Diseases, and,Howard Hughes Medical Institute, University of Michigan, Ann Arbor, Michigan, USA
| |
Collapse
|
3
|
Wei W, Liu Z, Zhang C, Khoriaty R, Zhu M, Zhang B. A common human missense mutation of vesicle coat protein SEC23B leads to growth restriction and chronic pancreatitis in mice. J Biol Chem 2021; 298:101536. [PMID: 34954140 PMCID: PMC8760524 DOI: 10.1016/j.jbc.2021.101536] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 12/17/2021] [Accepted: 12/18/2021] [Indexed: 11/16/2022] Open
Affiliation(s)
- Wei Wei
- Genomic Medicine Institute, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio, USA
| | - Zhigang Liu
- Genomic Medicine Institute, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio, USA
| | - Chao Zhang
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Rami Khoriaty
- Departments of Internal Medicine, Cell and Developmental Biology and Rogel Cancer Center, University of Michigan, Ann Arbor, Michigan, USA
| | - Min Zhu
- Department of Pathology, Xinjiang Key Laboratory of Clinical Genetic Testing and Biomedical Information, Karamay Central Hospital, Karamay, China.
| | - Bin Zhang
- Genomic Medicine Institute, Lerner Research Institute of Cleveland Clinic, Cleveland, Ohio, USA.
| |
Collapse
|
4
|
Bisnett BJ, Condon BM, Linhart NA, Lamb CH, Huynh DT, Bai J, Smith TJ, Hu J, Georgiou GR, Boyce M. Evidence for nutrient-dependent regulation of the COPII coat by O-GlcNAcylation. Glycobiology 2021; 31:1102-1120. [PMID: 34142147 PMCID: PMC8457363 DOI: 10.1093/glycob/cwab055] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2020] [Revised: 06/01/2021] [Accepted: 06/03/2021] [Indexed: 12/18/2022] Open
Abstract
O-linked β-N-acetylglucosamine (O-GlcNAc) is a dynamic form of intracellular glycosylation common in animals, plants and other organisms. O-GlcNAcylation is essential in mammalian cells and is dysregulated in myriad human diseases, such as cancer, neurodegeneration and metabolic syndrome. Despite this pathophysiological significance, key aspects of O-GlcNAc signaling remain incompletely understood, including its impact on fundamental cell biological processes. Here, we investigate the role of O-GlcNAcylation in the coat protein II complex (COPII), a system universally conserved in eukaryotes that mediates anterograde vesicle trafficking from the endoplasmic reticulum. We identify new O-GlcNAcylation sites on Sec24C, Sec24D and Sec31A, core components of the COPII system, and provide evidence for potential nutrient-sensitive pathway regulation through site-specific glycosylation. Our work suggests a new connection between metabolism and trafficking through the conduit of COPII protein O-GlcNAcylation.
Collapse
Affiliation(s)
- Brittany J Bisnett
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
| | - Brett M Condon
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
| | - Noah A Linhart
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
| | - Caitlin H Lamb
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
| | - Duc T Huynh
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
| | - Jingyi Bai
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
| | - Timothy J Smith
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
| | - Jimin Hu
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
| | - George R Georgiou
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
| | - Michael Boyce
- Department of Biochemistry, Duke University School of Medicine, Durham, NC 27710, USA
| |
Collapse
|
5
|
Nakagawa H, Komori M, Nishimura K. Carbon tetrachloride suppresses ER-Golgi transport by inhibiting COPII vesicle formation on the ER membrane in the RLC-16 hepatocyte cell line. Cell Biol Int 2021; 45:633-641. [PMID: 33247607 DOI: 10.1002/cbin.11510] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 10/20/2020] [Accepted: 11/21/2020] [Indexed: 01/14/2023]
Abstract
Carbon tetrachloride (CCl4 ) causes hepatotoxicity in mammals, with its hepatocytic metabolism producing radicals that attack the intracellular membrane system and destabilize intracellular vesicle transport. Inhibition of intracellular transport causes lipid droplet retention and abnormal protein distribution. The intracellular transport of synthesized lipids and proteins from the endoplasmic reticulum (ER) to the Golgi apparatus is performed by coat complex II (COPII) vesicle transport, but how CCl4 inhibits COPII vesicle transport has not been elucidated. COPII vesicle formation on the ER membrane is initiated by the recruitment of Sar1 protein from the cytoplasm to the ER membrane, followed by that of the COPII coat constituent proteins (Sec23, Sec24, Sec13, and Sec31). In this study, we evaluated the effect of CCl4 on COPII vesicle formation using the RLC-16 rat hepatocyte cell line. Our results showed that CCl4 suppressed ER-Golgi transport in RLC-16 cells. Using a reconstituted system of rat liver tissue-derived cytoplasm and RLC-16 cell-derived ER membranes, CCl4 treatment inhibited the recruitment of Sar1 and Sec13 from the cytosolic fraction to ER membranes. CCl4 -induced changes in the ER membrane accordingly inhibited the accumulation of COPII vesicle-coated constituent proteins on the ER membrane, as well as the formation of COPII vesicles, which suppressed lipid and protein transport between the ER and Golgi apparatus. Our data suggest that CCl4 inhibits ER-Golgi intracellular transport by inhibiting COPII vesicle formation on the ER membrane in hepatocytes.
Collapse
Affiliation(s)
- Hiroshi Nakagawa
- Laboratory of Toxicology, Graduate School of Veterinary Sciences, Osaka Prefecture University, Izumisano, Osaka, Japan
| | - Masayuki Komori
- Laboratory of Cellular and Molecular Biology, Graduate School of Veterinary Sciences, Osaka Prefecture University, Izumisano, Osaka, Japan
| | - Kazuhiko Nishimura
- Laboratory of Toxicology, Graduate School of Veterinary Sciences, Osaka Prefecture University, Izumisano, Osaka, Japan
| |
Collapse
|
6
|
Abstract
The functions of coat protein complex II (COPII) coats in cargo packaging and the creation of vesicles at the endoplasmic reticulum are conserved in eukaryotic protein secretion. Standard COPII vesicles, however, cannot handle the secretion of metazoan-specific cargoes such as procollagens, apolipoproteins, and mucins. Metazoans have thus evolved modules centered on proteins like TANGO1 (transport and Golgi organization 1) to engage COPII coats and early secretory pathway membranes to engineer a novel mode of cargo export at the endoplasmic reticulum.
Collapse
Affiliation(s)
- I Raote
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona 08003, Spain; ,
| | - V Malhotra
- Centre for Genomic Regulation (CRG), The Barcelona Institute of Science and Technology, Barcelona 08003, Spain; , .,Universitat Pompeu Fabra (UPF), Barcelona 08002, Spain.,Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona 08010, Spain
| |
Collapse
|
7
|
Dieterich IA, Cui Y, Braun MM, Lawton AJ, Robinson NH, Peotter JL, Yu Q, Casler JC, Glick BS, Audhya A, Denu JM, Li L, Puglielli L. Acetyl-CoA flux from the cytosol to the ER regulates engagement and quality of the secretory pathway. Sci Rep 2021; 11:2013. [PMID: 33479349 PMCID: PMC7820588 DOI: 10.1038/s41598-021-81447-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 01/05/2021] [Indexed: 12/18/2022] Open
Abstract
Nε-lysine acetylation in the ER is an essential component of the quality control machinery. ER acetylation is ensured by a membrane transporter, AT-1/SLC33A1, which translocates cytosolic acetyl-CoA into the ER lumen, and two acetyltransferases, ATase1 and ATase2, which acetylate nascent polypeptides within the ER lumen. Dysfunctional AT-1, as caused by gene mutation or duplication events, results in severe disease phenotypes. Here, we used two models of AT-1 dysregulation to investigate dynamics of the secretory pathway: AT-1 sTg, a model of systemic AT-1 overexpression, and AT-1S113R/+, a model of AT-1 haploinsufficiency. The animals displayed reorganization of the ER, ERGIC, and Golgi apparatus. In particular, AT-1 sTg animals displayed a marked delay in Golgi-to-plasma membrane protein trafficking, significant alterations in Golgi-based N-glycan modification, and a marked expansion of the lysosomal network. Collectively our results indicate that AT-1 is essential to maintain proper organization and engagement of the secretory pathway.
Collapse
Affiliation(s)
- Inca A Dieterich
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.,Waisman Center, University of Wisconsin-Madison, Madison, WI, USA.,Neuroscience Training Program, University of Wisconsin-Madison, Madison, WI, USA
| | - Yusi Cui
- School of Pharmacy and Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - Megan M Braun
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.,Waisman Center, University of Wisconsin-Madison, Madison, WI, USA.,Neuroscience Training Program, University of Wisconsin-Madison, Madison, WI, USA
| | - Alexis J Lawton
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI, USA.,Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI, USA
| | - Nicklaus H Robinson
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA.,Waisman Center, University of Wisconsin-Madison, Madison, WI, USA
| | - Jennifer L Peotter
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - Qing Yu
- School of Pharmacy and Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA.,Harvard Medical School, Boston, MA, USA
| | - Jason C Casler
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL, USA
| | - Benjamin S Glick
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, IL, USA
| | - Anjon Audhya
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - John M Denu
- Department of Biomolecular Chemistry, University of Wisconsin-Madison, Madison, WI, USA.,Wisconsin Institute for Discovery, University of Wisconsin-Madison, Madison, WI, USA
| | - Lingjun Li
- School of Pharmacy and Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA.
| | - Luigi Puglielli
- Department of Medicine, University of Wisconsin-Madison, Madison, WI, USA. .,Waisman Center, University of Wisconsin-Madison, Madison, WI, USA. .,Geriatric Research Education Clinical Center, Veterans Affairs Medical Center, Madison, WI, USA. .,Department of Neuroscience, University of Wisconsin-Madison, Madison, WI, USA.
| |
Collapse
|
8
|
Westrate LM, Hoyer MJ, Nash MJ, Voeltz GK. Vesicular and uncoated Rab1-dependent cargo carriers facilitate ER to Golgi transport. J Cell Sci 2020; 133:jcs239814. [PMID: 32616562 PMCID: PMC7390636 DOI: 10.1242/jcs.239814] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Accepted: 06/19/2020] [Indexed: 01/24/2023] Open
Abstract
Secretory cargo is recognized, concentrated and trafficked from endoplasmic reticulum (ER) exit sites (ERES) to the Golgi. Cargo export from the ER begins when a series of highly conserved COPII coat proteins accumulate at the ER and regulate the formation of cargo-loaded COPII vesicles. In animal cells, capturing live de novo cargo trafficking past this point is challenging; it has been difficult to discriminate whether cargo is trafficked to the Golgi in a COPII-coated vesicle. Here, we describe a recently developed live-cell cargo export system that can be synchronously released from ERES to illustrate de novo trafficking in animal cells. We found that components of the COPII coat remain associated with the ERES while cargo is extruded into COPII-uncoated, non-ER associated, Rab1 (herein referring to Rab1a or Rab1b)-dependent carriers. Our data suggest that, in animal cells, COPII coat components remain stably associated with the ER at exit sites to generate a specialized compartment, but once cargo is sorted and organized, Rab1 labels these export carriers and facilitates efficient forward trafficking.This article has an associated First Person interview with the first author of the paper.
Collapse
Affiliation(s)
- Laura M Westrate
- Department of Chemistry and Biochemistry, Calvin University, Grand Rapids, MI 49546, USA
| | - Melissa J Hoyer
- Howard Hughes Medical Institute, Department of Molecular, Cellular, and Developmental Biology, University of Colorado-Boulder, Boulder, CO 80309, USA
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado-Boulder, Boulder, CO 80309, USA
| | - Michael J Nash
- Howard Hughes Medical Institute, Department of Molecular, Cellular, and Developmental Biology, University of Colorado-Boulder, Boulder, CO 80309, USA
| | - Gia K Voeltz
- Howard Hughes Medical Institute, Department of Molecular, Cellular, and Developmental Biology, University of Colorado-Boulder, Boulder, CO 80309, USA
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado-Boulder, Boulder, CO 80309, USA
| |
Collapse
|
9
|
Jennings W, Epand RM. CDP-diacylglycerol, a critical intermediate in lipid metabolism. Chem Phys Lipids 2020; 230:104914. [PMID: 32360136 DOI: 10.1016/j.chemphyslip.2020.104914] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 04/01/2020] [Accepted: 04/13/2020] [Indexed: 12/13/2022]
Abstract
The roles of lipids expand beyond the basic building blocks of biological membranes. In addition to forming complex and dynamic barriers, the thousands of different lipid species in the cell contribute to essentially all the processes of life. Specific lipids are increasingly identified in cellular processes, including signal transduction, membrane trafficking, metabolic control and protein regulation. Tight control of their synthesis and degradation is essential for homeostasis. Most of the lipid molecules in the cell originate from a small number of critical intermediates. Thus, regulating the synthesis of intermediates is essential for lipid homeostasis and optimal biological functions. Cytidine diphosphate diacylglycerol (CDP-DAG) is an intermediate which occupies a branch point in lipid metabolism. CDP-DAG is incorporated into different synthetic pathways to form distinct phospholipid end-products depending on its location of synthesis. Identification and characterization of CDP-DAG synthases which catalyze the synthesis of CDP-DAG has been hampered by difficulties extracting these membrane-bound enzymes for purification. Recent developments have clarified the cellular localization of the CDP-DAG synthases and identified a new unrelated CDP-DAG synthase enzyme. These findings have contributed to a deeper understanding of the extensive synthetic and signaling networks stemming from this key lipid intermediate.
Collapse
Affiliation(s)
- William Jennings
- Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada
| | - Richard M Epand
- Department of Biochemistry and Biomedical Sciences, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada.
| |
Collapse
|
10
|
The Role of Secretory Pathways in Candida albicans Pathogenesis. J Fungi (Basel) 2020; 6:jof6010026. [PMID: 32102426 PMCID: PMC7151058 DOI: 10.3390/jof6010026] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 02/19/2020] [Accepted: 02/20/2020] [Indexed: 12/17/2022] Open
Abstract
Candida albicans is a fungus that is a commensal organism and a member of the normal human microbiota. It has the ability to transition into an opportunistic invasive pathogen. Attributes that support pathogenesis include secretion of virulence-associated proteins, hyphal formation, and biofilm formation. These processes are supported by secretion, as defined in the broad context of membrane trafficking. In this review, we examine the role of secretory pathways in Candida virulence, with a focus on the model opportunistic fungal pathogen, Candida albicans.
Collapse
|
11
|
Sun MS, Zhang J, Jiang LQ, Pan YX, Tan JY, Yu F, Guo L, Yin L, Shen C, Shu HB, Liu Y. TMED2 Potentiates Cellular IFN Responses to DNA Viruses by Reinforcing MITA Dimerization and Facilitating Its Trafficking. Cell Rep 2019; 25:3086-3098.e3. [PMID: 30540941 DOI: 10.1016/j.celrep.2018.11.048] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 10/22/2018] [Accepted: 11/12/2018] [Indexed: 02/06/2023] Open
Abstract
Mediator of IRF3 activation (MITA), also known as stimulator of interferon genes (STING), plays a vital role in the innate immune responses to cytosolic dsDNA. The trafficking of MITA from the ER to perinuclear vesicles is necessary for its activation of the downstream molecules, which lead to the production of interferons and pro-inflammatory cytokines. However, the exact mechanism of MITA activation remains elusive. Here, we report that transmembrane emp24 protein transport domain containing 2 (TMED2) potentiates DNA virus-induced MITA signaling. The suppression or deletion of TMED2 markedly impairs the production of type I IFNs upon HSV-1 infection. TMED2-deficient cells harbor greater HSV-1 load than the control cells. Mechanistically, TMED2 associates with MITA only upon viral stimulation, and this process potentiates MITA activation by reinforcing its dimerization and facilitating its trafficking. These findings suggest an essential role of TMED2 in cellular IFN responses to DNA viruses.
Collapse
Affiliation(s)
- Ming-Shun Sun
- State Key Laboratory of Virology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Jie Zhang
- State Key Laboratory of Virology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Li-Qun Jiang
- State Key Laboratory of Virology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Yi-Xi Pan
- State Key Laboratory of Virology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Jiao-Yi Tan
- State Key Laboratory of Virology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Fang Yu
- Department of Pathology, Zhongnan Hospital of Wuhan University, Wuhan 430072, China
| | - Lin Guo
- State Key Laboratory of Virology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Lei Yin
- State Key Laboratory of Virology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Chao Shen
- State Key Laboratory of Virology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China
| | - Hong-Bing Shu
- State Key Laboratory of Virology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China; Medical Research Institute of Wuhan University, Wuhan University, Wuhan 430072, China
| | - Yu Liu
- State Key Laboratory of Virology, Hubei Key Laboratory of Cell Homeostasis, College of Life Sciences, Wuhan University, Wuhan 430072, China.
| |
Collapse
|
12
|
Anderson NS, Barlowe C. Conserved juxtamembrane domains in the yeast golgin Coy1 drive assembly of a megadalton-sized complex and mediate binding to tethering and SNARE proteins. J Biol Chem 2019; 294:9690-9705. [PMID: 31073031 DOI: 10.1074/jbc.ra119.008107] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2019] [Revised: 04/26/2019] [Indexed: 12/13/2022] Open
Abstract
The architecture and organization of the Golgi complex depend on a family of coiled-coil proteins called golgins. Golgins are thought to form extended homodimers that are C-terminally anchored to Golgi membranes, whereas their N termini extend into the cytoplasm to initiate vesicle capture. Previously, we reported that the Saccharomyces cerevisiae golgin Coy1 contributes to intra-Golgi retrograde transport and binds to the conserved oligomeric Golgi (COG) complex and multiple retrograde Golgi Q-SNAREs (where SNARE is soluble NSF-attachment protein receptor). Here, using various engineered yeast strains, membrane protein extraction and fractionation methods, and in vitro binding assays, we mapped the Coy1 regions responsible for these activities. We also report that Coy1 assembles into a megadalton-size complex and that assembly of this complex depends on the most C-terminal coiled-coil and a conserved region between this coiled-coil and the transmembrane domain of Coy1. We found that this conserved region is necessary and sufficient for binding the SNARE protein Sed5 and the COG complex. Mutagenesis of conserved arginine residues within the C-terminal coiled-coil disrupted oligomerization, binding, and function of Coy1. Our findings indicate that the stable incorporation of Coy1 into a higher-order oligomer is required for its interactions and role in maintaining Golgi homeostasis. We propose that Coy1 assembles into a docking platform that directs COG-bound vesicles toward cognate SNAREs on the Golgi membrane.
Collapse
Affiliation(s)
- Nadine S Anderson
- From the Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755
| | - Charles Barlowe
- From the Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire 03755
| |
Collapse
|
13
|
Zamponi N, Zamponi E, Mayol GF, Lanfredi-Rangel A, Svärd SG, Touz MC. Endoplasmic reticulum is the sorting core facility in the Golgi-lacking protozoanGiardia lamblia. Traffic 2017; 18:604-621. [DOI: 10.1111/tra.12501] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Revised: 07/02/2017] [Accepted: 07/06/2017] [Indexed: 01/13/2023]
Affiliation(s)
- Nahuel Zamponi
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC - CONICET; Universidad Nacional de Córdoba; Córdoba Argentina
| | - Emiliano Zamponi
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC - CONICET; Universidad Nacional de Córdoba; Córdoba Argentina
| | - Gonzalo F. Mayol
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC - CONICET; Universidad Nacional de Córdoba; Córdoba Argentina
| | | | - Staffan G. Svärd
- Department of Cell and Molecular Biology; Uppsala University; Uppsala Sweden
| | - María C. Touz
- Instituto de Investigación Médica Mercedes y Martín Ferreyra, INIMEC - CONICET; Universidad Nacional de Córdoba; Córdoba Argentina
| |
Collapse
|
14
|
Inhibition of PLD1 activity causes ER stress via regulation of COPII vesicle formation. Biochem Biophys Res Commun 2017. [DOI: 10.1016/j.bbrc.2017.06.137] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
15
|
Yavuz S, Warren G. A role for Sar1 and ARF1 GTPases during Golgi biogenesis in the protozoan parasite Trypanosoma brucei. Mol Biol Cell 2017; 28:1782-1791. [PMID: 28495798 PMCID: PMC5491186 DOI: 10.1091/mbc.e17-03-0151] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 05/01/2017] [Accepted: 05/05/2017] [Indexed: 11/11/2022] Open
Abstract
A single Golgi stack is duplicated and partitioned into two daughter cells during the cell cycle of the protozoan parasite Trypanosoma brucei The source of components required to generate the new Golgi and the mechanism by which it forms are poorly understood. Using photoactivatable GFP, we show that the existing Golgi supplies components directly to the newly forming Golgi in both intact and semipermeabilized cells. The movement of a putative glycosyltransferase, GntB, requires the Sar1 and ARF1 GTPases in intact cells. In addition, we show that transfer of GntB from the existing Golgi to the new Golgi can be recapitulated in semipermeabilized cells and is sensitive to the GTP analogue GTPγS. We suggest that the existing Golgi is a key source of components required to form the new Golgi and that this process is regulated by small GTPases.
Collapse
Affiliation(s)
- Sevil Yavuz
- Max F. Perutz Laboratories, University of Vienna, and Medical University of Vienna, Vienna Biocenter, Vienna A-1030, Austria
| | - Graham Warren
- Max F. Perutz Laboratories, University of Vienna, and Medical University of Vienna, Vienna Biocenter, Vienna A-1030, Austria
| |
Collapse
|
16
|
Amodio G, Margarucci L, Moltedo O, Casapullo A, Remondelli P. Identification of Cysteine Ubiquitylation Sites on the Sec23A Protein of the COPII Complex Required for Vesicle Formation from the ER. Open Biochem J 2017; 11:36-46. [PMID: 28553408 PMCID: PMC5427705 DOI: 10.2174/1874091x01711010036] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 02/09/2017] [Accepted: 03/17/2017] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND COPII is a multiprotein complex that surrounds carrier vesicles budding from the Endoplasmic Reticulum and allows the recruitment of secretory proteins. The Sec23a protein plays a crucial role in the regulation of the dynamics of COPII formation ensuring the proper function of the secretory pathway. OBJECTIVE Since few evidences suggest that ubiquitylation could have a role in the COPII regulation, the present study was aimed to establish whether the Sec23a component of the vesicular envelope COPII could be ubiquitylated. METHOD Sec23a ubiquitylation was revealed by co-immunoprecipitation experiments. Recombinant Sec23a was gel-purified and analyzed by mass spectrometry subjected to trypsin proteolysis. Signature peptides were identified by the presence of Gly-Gly remnants from the C-terminus of the ubiquitin attached to the amino acid residues of the substrate. Recombinant Sec23a proteins bearing mutations in the ubiquitylation sites were used to evaluate the effect of ubiquitylation in the formation of COPII. RESULTS We identified two cysteine ubiquitylation sites showed at position 432 and 449 of the Sec23a protein sequence. Interestingly, we revealed that the amino acid residues of Sec23a joined to ubiquitin were cysteine instead of the conventional lysine residues. This unconventional ubiquitylation consists of the addition of one single ubiquitin moiety that is not required for Sec23a degradation. Immunofluorescence results showed that Sec23a ubiquitylation might influence COPII formation by modulating Sec23a interaction with the ER membrane. Presumably, this regulation could occur throughout continual ubiquitylation/de-ubiquityliation cycles. CONCLUSION Our results suggest a novel regulatory mechanism for the Sec23a function that could be crucial in several pathophysiological events known to alter COPII recycling.
Collapse
Affiliation(s)
- Giuseppina Amodio
- Dipartimento di Medicina, Chirurgia e Odontoiatria "Scuola Medica Salernitana", Università degli Studi di Salerno, 84084 Baronissi-Salerno, Italy
| | - Luigi Margarucci
- Dipartimento di Farmacia, Università degli Studi di Salerno, 84034 Fisciano-Salerno, Italy
| | - Ornella Moltedo
- Dipartimento di Farmacia, Università degli Studi di Salerno, 84034 Fisciano-Salerno, Italy
| | - Agostino Casapullo
- Dipartimento di Farmacia, Università degli Studi di Salerno, 84034 Fisciano-Salerno, Italy
| | - Paolo Remondelli
- Dipartimento di Medicina, Chirurgia e Odontoiatria "Scuola Medica Salernitana", Università degli Studi di Salerno, 84084 Baronissi-Salerno, Italy
| |
Collapse
|
17
|
Khoriaty R, Everett L, Chase J, Zhu G, Hoenerhoff M, McKnight B, Vasievich MP, Zhang B, Tomberg K, Williams J, Maillard I, Ginsburg D. Pancreatic SEC23B deficiency is sufficient to explain the perinatal lethality of germline SEC23B deficiency in mice. Sci Rep 2016; 6:27802. [PMID: 27297878 PMCID: PMC4906273 DOI: 10.1038/srep27802] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Accepted: 05/25/2016] [Indexed: 01/18/2023] Open
Abstract
In humans, loss of function mutations in SEC23B result in Congenital Dyserythropoietic Anemia type II (CDAII), a disease limited to defective erythroid development. Patients with two nonsense SEC23B mutations have not been reported, suggesting that complete SEC23B deficiency might be lethal. We previously reported that SEC23B-deficient mice die perinatally, exhibiting massive pancreatic degeneration and that mice with hematopoietic SEC23B deficiency do not exhibit CDAII. We now show that SEC23B deficiency restricted to the pancreas is sufficient to explain the lethality observed in mice with global SEC23B-deficiency. Immunohistochemical stains demonstrate an acinar cell defect but normal islet cells. Mammalian genomes contain two Sec23 paralogs, Sec23A and Sec23B. The encoded proteins share ~85% amino acid sequence identity. We generate mice with pancreatic SEC23A deficiency and demonstrate that these mice survive normally, exhibiting normal pancreatic weights and histology. Taken together, these data demonstrate that SEC23B but not SEC23A is essential for murine pancreatic development. We also demonstrate that two BAC transgenes spanning Sec23b rescue the lethality of mice homozygous for a Sec23b gene trap allele, excluding a passenger gene mutation as the cause of the pancreatic lethality, and indicating that the regulatory elements critical for Sec23b pancreatic function reside within the BAC transgenes.
Collapse
Affiliation(s)
- Rami Khoriaty
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Lesley Everett
- University of Michigan Medical School, Ann Arbor, MI, USA
| | - Jennifer Chase
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
| | - Guojing Zhu
- Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
| | - Mark Hoenerhoff
- In Vivo Animal Core, Unit for Laboratory Animal Medicine, University of Michigan, Ann Arbor, MI, USA
| | - Brooke McKnight
- College of Literature Science and the Arts, University of Michigan, Ann Arbor, MI, USA
| | | | - Bin Zhang
- Genomic Medicine Institute, Cleveland Clinic Lerner Research Institute, Cleveland, OH, USA
| | - Kärt Tomberg
- Department of Human Genetics, University of Michigan, Ann Arbor, MI, USA
| | - John Williams
- Department of Physiology, University of Michigan, Ann Arbor, MI, USA
| | - Ivan Maillard
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA.,Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA
| | - David Ginsburg
- Department of Internal Medicine, University of Michigan, Ann Arbor, MI, USA.,Life Sciences Institute, University of Michigan, Ann Arbor, MI, USA.,Department of Human Genetics, University of Michigan, Ann Arbor, MI, USA.,Department of Pediatrics and Communicable Diseases, University of Michigan, Ann Arbor, MI, USA.,Howard Hughes Medical Institute, University of Michigan, Ann Arbor, MI, USA
| |
Collapse
|
18
|
Hu H, Gourguechon S, Wang CC, Li Z. The G1 Cyclin-dependent Kinase CRK1 in Trypanosoma brucei Regulates Anterograde Protein Transport by Phosphorylating the COPII Subunit Sec31. J Biol Chem 2016; 291:15527-39. [PMID: 27252375 PMCID: PMC4957039 DOI: 10.1074/jbc.m116.715185] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Indexed: 01/02/2023] Open
Abstract
Transport of secretory proteins from the endoplasmic reticulum to the Golgi is mediated by the coat protein II (COPII) complex comprising a Sec23-Sec24 heterodimer and a Sec13-Sec31 heterotetramer. The mechanisms underlying COPII-mediated protein trafficking have been well defined, but the extent of regulation of this secretory machinery by cellular signaling pathways remains poorly understood. Here, we report that CRK1, a G1 cyclin-dependent kinase in Trypanosoma brucei, regulates anterograde protein trafficking by phosphorylating Sec31. Depletion of CRK1 abolished anterograde transport of the secretory protein and disrupted the localization of multiple Golgi proteins, reminiscent of Sec31 depletion. CRK1 phosphorylates Sec31 at multiple serine/threonine sites, and mutation of these phosphosites to alanine recapitulates the protein trafficking defects caused by Sec31 depletion. Mutation of these CRK1 phosphosites to aspartate restored Sec31 function. Taken together, these results uncover a novel function of CRK1 in anterograde protein trafficking and elucidate the mechanistic role of CRK1 in protein trafficking through regulation of the COPII subunit Sec31.
Collapse
Affiliation(s)
- Huiqing Hu
- From the Department of Microbiology and Molecular Genetics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas 77030 and
| | - Stéphane Gourguechon
- the Department of Pharmaceutical Chemistry, University of California at San Francisco, San Francisco, California 94158
| | - Ching C Wang
- the Department of Pharmaceutical Chemistry, University of California at San Francisco, San Francisco, California 94158
| | - Ziyin Li
- From the Department of Microbiology and Molecular Genetics, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, Texas 77030 and
| |
Collapse
|
19
|
Yehia L, Niazi F, Ni Y, Ngeow J, Sankunny M, Liu Z, Wei W, Mester J, Keri R, Zhang B, Eng C. Germline Heterozygous Variants in SEC23B Are Associated with Cowden Syndrome and Enriched in Apparently Sporadic Thyroid Cancer. Am J Hum Genet 2015; 97:661-76. [PMID: 26522472 DOI: 10.1016/j.ajhg.2015.10.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2015] [Accepted: 09/30/2015] [Indexed: 12/12/2022] Open
Abstract
Cancer-predisposing genes associated with inherited cancer syndromes help explain mechanisms of sporadic carcinogenesis and often inform normal development. Cowden syndrome (CS) is an autosomal-dominant disorder characterized by high lifetime risks of epithelial cancers, such that ∼50% of affected individuals are wild-type for known cancer-predisposing genes. Using whole-exome and Sanger sequencing of a multi-generation CS family affected by thyroid and other cancers, we identified a pathogenic missense heterozygous SEC23B variant (c.1781T>G [p.Val594Gly]) that segregates with the phenotype. We also found germline heterozygous SEC23B variants in 3/96 (3%) unrelated mutation-negative CS probands with thyroid cancer and in The Cancer Genome Atlas (TCGA), representing apparently sporadic cancers. We note that the TCGA thyroid cancer dataset is enriched with unique germline deleterious SEC23B variants associated with a significantly younger age of onset. SEC23B encodes Sec23 homolog B (S. cerevisiae), a component of coat protein complex II (COPII), which transports proteins from the endoplasmic reticulum (ER) to the Golgi apparatus. Interestingly, germline homozygous or compound-heterozygous SEC23B mutations cause an unrelated disorder, congenital dyserythropoietic anemia type II, and SEC23B-deficient mice suffer from secretory organ degeneration due to ER-stress-associated apoptosis. By characterizing the p.Val594Gly variant in a normal thyroid cell line, we show that it is a functional alteration that results in ER-stress-mediated cell-colony formation and survival, growth, and invasion, which reflect aspects of a cancer phenotype. Our findings suggest a different role for SEC23B, whereby germline heterozygous variants associate with cancer predisposition potentially mediated by ER stress "addiction."
Collapse
|
20
|
Springer S, Malkus P, Borchert B, Wellbrock U, Duden R, Schekman R. Regulated Oligomerization Induces Uptake of a Membrane Protein into COPII Vesicles Independent of Its Cytosolic Tail. Traffic 2014; 15:531-45. [DOI: 10.1111/tra.12157] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Revised: 01/07/2014] [Accepted: 01/30/2014] [Indexed: 12/22/2022]
Affiliation(s)
| | - Per Malkus
- Department of Systems Biology; Harvard Medical School; Boston MA 02115 USA
| | - Britta Borchert
- Biochemistry and Cell Biology; Jacobs University Bremen; Bremen Germany
| | - Ursula Wellbrock
- Biochemistry and Cell Biology; Jacobs University Bremen; Bremen Germany
| | - Rainer Duden
- Centre for Structural and Cell Biology in Medicine, Institute of Biology; University of Lübeck; Lübeck Germany
| | - Randy Schekman
- Howard Hughes Medical Institute and Department of Molecular and Cell Biology; University of California, Berkeley; Berkeley CA 94720 USA
| |
Collapse
|
21
|
Karim S, Aronsson H. The puzzle of chloroplast vesicle transport - involvement of GTPases. FRONTIERS IN PLANT SCIENCE 2014; 5:472. [PMID: 25295043 PMCID: PMC4171996 DOI: 10.3389/fpls.2014.00472] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2014] [Accepted: 08/28/2014] [Indexed: 05/04/2023]
Abstract
In the cytosol of plant cells vesicle transport occurs via secretory pathways among the endoplasmic reticulum network, Golgi bodies, secretory granules, endosome, and plasma membrane. Three systems transfer lipids, proteins and other important molecules through aqueous spaces to membrane-enclosed compartments, via vesicles that bud from donor membranes, being coated and uncoated before tethered and fused with acceptor membranes. In addition, molecular, biochemical and ultrastructural evidence indicates presence of a vesicle transport system in chloroplasts. Little is known about the protein components of this system. However, as chloroplasts harbor the photosynthetic apparatus that ultimately supports most organisms on the planet, close attention to their pathways is warranted. This may also reveal novel diversification and/or distinct solutions to the problems posed by the targeted intra-cellular trafficking of important molecules. To date two homologs to well-known yeast cytosolic vesicle transport proteins, CPSAR1 and CPRabA5e (CP, chloroplast localized), have been shown to have roles in chloroplast vesicle transport, both being GTPases. Bioinformatic data indicate that several homologs of cytosolic vesicle transport system components are putatively chloroplast-localized and in addition other proteins have been implicated to participate in chloroplast vesicle transport, including vesicle-inducing protein in plastids 1, thylakoid formation 1, snowy cotyledon 2/cotyledon chloroplast biogenesis factor, curvature thylakoid 1 proteins, and a dynamin like GTPase FZO-like protein. Several putative potential cargo proteins have also been identified, including building blocks of the photosynthetic apparatus. Here we discuss details of the largely unknown putative chloroplast vesicle transport system, focusing on GTPase-related components.
Collapse
Affiliation(s)
| | - Henrik Aronsson
- *Correspondence: Henrik Aronsson, Department of Biological and Environmental Sciences, University of Gothenburg, Box 461, 405 30 Gothenburg, Sweden e-mail:
| |
Collapse
|
22
|
Takagi J, Renna L, Takahashi H, Koumoto Y, Tamura K, Stefano G, Fukao Y, Kondo M, Nishimura M, Shimada T, Brandizzi F, Hara-Nishimura I. MAIGO5 functions in protein export from Golgi-associated endoplasmic reticulum exit sites in Arabidopsis. THE PLANT CELL 2013; 25:4658-75. [PMID: 24280388 PMCID: PMC3875742 DOI: 10.1105/tpc.113.118158] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2013] [Revised: 10/08/2013] [Accepted: 10/22/2013] [Indexed: 05/19/2023]
Abstract
Plant cells face unique challenges to efficiently export cargo from the endoplasmic reticulum (ER) to mobile Golgi stacks. Coat protein complex II (COPII) components, which include two heterodimers of Secretory23/24 (Sec23/24) and Sec13/31, facilitate selective cargo export from the ER; however, little is known about the mechanisms that regulate their recruitment to the ER membrane, especially in plants. Here, we report a protein transport mutant of Arabidopsis thaliana, named maigo5 (mag5), which abnormally accumulates precursor forms of storage proteins in seeds. mag5-1 has a deletion in the putative ortholog of the Saccharomyces cerevisiae and Homo sapiens Sec16, which encodes a critical component of ER exit sites (ERESs). mag mutants developed abnormal structures (MAG bodies) within the ER and exhibited compromised ER export. A functional MAG5/SEC16A-green fluorescent protein fusion localized at Golgi-associated cup-shaped ERESs and cycled on and off these sites at a slower rate than the COPII coat. MAG5/SEC16A interacted with SEC13 and SEC31; however, in the absence of MAG5/SEC16A, recruitment of the COPII coat to ERESs was accelerated. Our results identify a key component of ER export in plants by demonstrating that MAG5/SEC16A is required for protein export at ERESs that are associated with mobile Golgi stacks, where it regulates COPII coat turnover.
Collapse
Affiliation(s)
- Junpei Takagi
- Department of Botany, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Luciana Renna
- Department of Energy, Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824
| | - Hideyuki Takahashi
- Department of Botany, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Yasuko Koumoto
- Department of Botany, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Kentaro Tamura
- Department of Botany, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Giovanni Stefano
- Department of Energy, Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824
| | - Yoichiro Fukao
- Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma 630-0101, Japan
| | - Maki Kondo
- Department of Cell Biology, National Institute for Basic Biology, Okazaki 444-8585, Japan
| | - Mikio Nishimura
- Department of Cell Biology, National Institute for Basic Biology, Okazaki 444-8585, Japan
| | - Tomoo Shimada
- Department of Botany, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
| | - Federica Brandizzi
- Department of Energy, Plant Research Laboratory, Michigan State University, East Lansing, Michigan 48824
| | - Ikuko Hara-Nishimura
- Department of Botany, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto 606-8502, Japan
- Address correspondence to
| |
Collapse
|
23
|
Tanaka Y, Nishimura K, Kawamukai M, Oshima A, Nakagawa T. Redundant function of two Arabidopsis COPII components, AtSec24B and AtSec24C, is essential for male and female gametogenesis. PLANTA 2013; 238:561-75. [PMID: 23779001 DOI: 10.1007/s00425-013-1913-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 06/05/2013] [Indexed: 05/08/2023]
Abstract
Anterograde vesicle transport from the endoplasmic reticulum to the Golgi apparatus is the start of protein transport through the secretory pathway, in which the transport is mediated by coat protein complex II (COPII)-coated vesicles. Therefore, most proteins synthesized on the endoplasmic reticulum are loaded as cargo into COPII vesicles. The COPII is composed of the small GTPase Sar1 and two types of protein complexes (Sec23/24 and Sec13/31). Of these five COPII components, Sec24 is thought to recognize cargo that is incorporated into COPII vesicles by directly interacting with the cargo. The Arabidopsis genome encodes three types of Sec24 homologs (AtSec24A, AtSec24B, and AtSec24C). The subcellular dynamics and function of AtSec24A have been characterized. The intracellular distributions and functions of other AtSec24 proteins are not known, and the functional differences among the three AtSec24s remain unclear. Here, we found that all three AtSec24s were expressed in similar parts of the plant body and showed the same subcellular localization pattern. AtSec24B knockout plant, but not AtSec24C knockdown plant, showed mild male sterility with reduction of pollen germination. Significant decrease of AtSec24B and AtSec24C expression affected male and female gametogenesis in Arabidopsis thaliana. Our results suggested that the redundant function of AtSec24B and AtSec24C is crucial for the development of plant reproductive cells. We propose that the COPII transport is involved in male and female gametogenesis in planta.
Collapse
Affiliation(s)
- Yuji Tanaka
- Department of Molecular and Functional Genomics, Center for Integrated Research in Science, Shimane University, Nishikawatsu 1060, Matsue, 690-8504, Japan
| | | | | | | | | |
Collapse
|
24
|
Vesicle coats: structure, function, and general principles of assembly. Trends Cell Biol 2013; 23:279-88. [DOI: 10.1016/j.tcb.2013.01.005] [Citation(s) in RCA: 139] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2012] [Revised: 12/27/2012] [Accepted: 01/10/2013] [Indexed: 01/03/2023]
|
25
|
Cutrona MB, Beznoussenko GV, Fusella A, Martella O, Moral P, Mironov AA. Silencing of mammalian Sar1 isoforms reveals COPII-independent protein sorting and transport. Traffic 2013; 14:691-708. [PMID: 23433038 DOI: 10.1111/tra.12060] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Revised: 02/16/2013] [Accepted: 02/21/2013] [Indexed: 01/01/2023]
Abstract
The Sar1 GTPase coordinates the assembly of coat protein complex-II (COPII) at specific sites of the endoplasmic reticulum (ER). COPII is required for ER-to-Golgi transport, as it provides a structural and functional framework to ship out protein cargoes produced in the ER. To investigate the requirement of COPII-mediated transport in mammalian cells, we used small interfering RNA (siRNA)-mediated depletion of Sar1A and Sar1B. We report that depletion of these two mammalian forms of Sar1 disrupts COPII assembly and the cells fail to organize transitional elements that coordinate classical ER-to-Golgi protein transfer. Under these conditions, minimal Golgi stacks are seen in proximity to juxtanuclear ER membranes that contain elements of the intermediate compartment, and from which these stacks coordinate biosynthetic transport of protein cargo, such as the vesicular stomatitis virus G protein and albumin. Here, transport of procollagen-I is inhibited. These data provide proof-of-principle for the contribution of alternative mechanisms that support biosynthetic trafficking in mammalian cells, providing evidence of a functional boundary associated with a bypass of COPII.
Collapse
Affiliation(s)
- Meritxell B Cutrona
- Department of Cellular and Translational Pharmacology, Consorzio Mario Negri Sud, Via Nazionale 8/A, 66030 Santa Maria Imbaro, Chieti, Italy.
| | | | | | | | | | | |
Collapse
|
26
|
Noble AJ, Zhang Q, O'Donnell J, Hariri H, Bhattacharya N, Marshall AG, Stagg SM. A pseudoatomic model of the COPII cage obtained from cryo-electron microscopy and mass spectrometry. Nat Struct Mol Biol 2013; 20:167-73. [PMID: 23262493 PMCID: PMC3565055 DOI: 10.1038/nsmb.2467] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Accepted: 11/09/2012] [Indexed: 12/23/2022]
Abstract
COPII vesicles transport proteins from the endoplasmic reticulum to the Golgi apparatus. Previous COPII-cage cryo-EM structures lacked the resolution necessary to determine the residues of Sec13 and Sec31 that mediate assembly and flexibility of the COPII cage. Here we present a 12-Å structure of the human COPII cage, where the tertiary structure of Sec13 and Sec31 is clearly identifiable. We employ this structure and a homology model of the Sec13-Sec31 complex to create a reliable pseudoatomic model of the COPII cage. We combined this model with hydrogen/deuterium-exchange MS analysis to characterize four distinct contact regions at the vertices of the COPII cage. Furthermore, we found that the two-fold symmetry of the Sec31 dimeric region in Sec13-Sec31 is broken upon cage formation and that the resulting hinge is essential to form the proper edge geometry in COPII cages.
Collapse
Affiliation(s)
- Alex J Noble
- Department of Physics, Florida State University, Tallahassee, Florida, USA
| | | | | | | | | | | | | |
Collapse
|
27
|
Abstract
Steady increase in the incidence of atherosclerosis is becoming a major concern not only in the United States but also in other countries. One of the major risk factors for the development of atherosclerosis is high concentrations of plasma low-density lipoprotein, which are metabolic products of very low-density lipoprotein (VLDL). VLDLs are synthesized and secreted by the liver. In this review, we discuss various stages through which VLDL particles go from their biogenesis to secretion in the circulatory system. Once VLDLs are synthesized in the lumen of the endoplasmic reticulum, they are transported to the Golgi. The transport of nascent VLDLs from the endoplasmic reticulum to Golgi is a complex multistep process, which is mediated by a specialized transport vesicle, the VLDL transport vesicle. The VLDL transport vesicle delivers VLDLs to the cis-Golgi lumen where nascent VLDLs undergo a number of essential modifications. The mature VLDL particles are then transported to the plasma membrane and secreted in the circulatory system. Understanding of molecular mechanisms and identification of factors regulating the complex intracellular VLDL trafficking will provide insight into the pathophysiology of various metabolic disorders associated with abnormal VLDL secretion and identify potential new therapeutic targets.
Collapse
Affiliation(s)
- Samata Tiwari
- Burnett School of Biomedical Sciences, College of Medicine, University of Central Florida, 6900 Lake Nona Boulevard, Orlando, FL 32827, USA
| | | |
Collapse
|
28
|
Abstract
Multiple diseases, hematologic and nonhematologic, result from defects in the early secretory pathway. Congenital dyserythropoietic anemia type II (CDAII) and combined deficiency of coagulation factors V and VIII (F5F8D) are the 2 known hematologic diseases that result from defects in the endoplasmic reticulum (ER)-to-Golgi transport system. CDAII is caused by mutations in the SEC23B gene, which encodes a core component of the coat protein complex II (COPII). F5F8D results from mutations in either LMAN1 (lectin mannose-binding protein 1) or MCFD2 (multiple coagulation factor deficiency protein 2), which encode the ER cargo receptor complex LMAN1-MCFD2. These diseases and their molecular pathogenesis are the focus of this review.
Collapse
|
29
|
Bhattacharya N, O Donnell J, Stagg SM. The structure of the Sec13/31 COPII cage bound to Sec23. J Mol Biol 2012; 420:324-34. [PMID: 22543240 DOI: 10.1016/j.jmb.2012.04.024] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Revised: 04/03/2012] [Accepted: 04/23/2012] [Indexed: 02/03/2023]
Abstract
Structural studies have revealed some of the organizing principles and mechanisms involved in the assembly of the COPII coat including the location of the Sec23/24 adapter layer. Previous studies, however, were unable to unambiguously determine the positions of Sec23 and Sec24 in the coat. Here, we have determined a cryogenic electron microscopic structure of Sec13/31 together with Sec23. Electron tomography revealed that the binding of Sec23 induces Sec13/31 to form a variety of different geometries including a cuboctahedron, as was previously characterized for Sec13/31 alone. Single-particle reconstruction of the Sec13/31-23 cuboctahedra revealed that the binding of Sec23 induces a conformational change in Sec13/31, resulting in a more extended conformation. Docking Sec23 crystal structures into the electron microscopy map suggested that Sec24 projects its cargo binding surface out into the large open faces of the coat. These results have implications for the mechanisms by which COPII transports large cargos, cargos with large intracellular domains, and for tethering complexes that must project out of the coat in order to interact with their binding partners. Furthermore, Sec23 binds Sec13/31 at two unique sites in the coat, which suggests that each site may have unique roles in the mechanisms of COPII vesiculation.
Collapse
|
30
|
Wu S, Avila-Sakar A, Kim J, Booth DS, Greenberg CH, Rossi A, Liao M, Li X, Alian A, Griner SL, Juge N, Yu Y, Mergel CM, Chaparro-Riggers J, Strop P, Tampé R, Edwards RH, Stroud RM, Craik CS, Cheng Y. Fabs enable single particle cryoEM studies of small proteins. Structure 2012; 20:582-92. [PMID: 22483106 PMCID: PMC3322386 DOI: 10.1016/j.str.2012.02.017] [Citation(s) in RCA: 128] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2011] [Revised: 01/31/2012] [Accepted: 02/17/2012] [Indexed: 01/08/2023]
Abstract
In spite of its recent achievements, the technique of single particle electron cryomicroscopy (cryoEM) has not been widely used to study proteins smaller than 100 kDa, although it is a highly desirable application of this technique. One fundamental limitation is that images of small proteins embedded in vitreous ice do not contain adequate features for accurate image alignment. We describe a general strategy to overcome this limitation by selecting a fragment antigen binding (Fab) to form a stable and rigid complex with a target protein, thus providing a defined feature for accurate image alignment. Using this approach, we determined a three-dimensional structure of an ∼65 kDa protein by single particle cryoEM. Because Fabs can be readily generated against a wide range of proteins by phage display, this approach is generally applicable to study many small proteins by single particle cryoEM.
Collapse
Affiliation(s)
- Shenping Wu
- The W.M. Keck Advanced Microscopy Laboratory, Department of Biochemistry and Biophysics, University of California San Francisco, 600 16th Street, San Francisco, CA 94158
| | - Agustin Avila-Sakar
- The W.M. Keck Advanced Microscopy Laboratory, Department of Biochemistry and Biophysics, University of California San Francisco, 600 16th Street, San Francisco, CA 94158
| | - JungMin Kim
- Department of Pharmaceutical Chemistry, University of California San Francisco, 600 16th Street, San Francisco, CA 94158
| | - David S. Booth
- The W.M. Keck Advanced Microscopy Laboratory, Department of Biochemistry and Biophysics, University of California San Francisco, 600 16th Street, San Francisco, CA 94158
- Graduate Group in Biophysics, University of California San Francisco, 600 16th Street, San Francisco, CA 94158
| | - Charles H. Greenberg
- The W.M. Keck Advanced Microscopy Laboratory, Department of Biochemistry and Biophysics, University of California San Francisco, 600 16th Street, San Francisco, CA 94158
- Graduate Group in Biophysics, University of California San Francisco, 600 16th Street, San Francisco, CA 94158
| | - Andrea Rossi
- Rinat Labs, Pfizer Inc., 230 East Grand Ave, South San Francisco, CA 94080
| | - Maofu Liao
- The W.M. Keck Advanced Microscopy Laboratory, Department of Biochemistry and Biophysics, University of California San Francisco, 600 16th Street, San Francisco, CA 94158
| | - Xueming Li
- The W.M. Keck Advanced Microscopy Laboratory, Department of Biochemistry and Biophysics, University of California San Francisco, 600 16th Street, San Francisco, CA 94158
| | - Akram Alian
- Faculty of Biology, Technion-Israel Institute of Technology, Haifa 32000, Israel
| | - Sarah L. Griner
- Department of Biochemistry and Biophysics, University of California San Francisco, 600 16th Street, San Francisco, CA 94158
| | - Narinobu Juge
- Department of Physiology and Department of Neurology, University of California San Francisco, 600 16th Street, San Francisco, CA 94158
| | - Yadong Yu
- The W.M. Keck Advanced Microscopy Laboratory, Department of Biochemistry and Biophysics, University of California San Francisco, 600 16th Street, San Francisco, CA 94158
| | - Claudia M. Mergel
- Institute of Biochemistry, Biocenter, Goethe-University Frankfurt, Max-von-Laue-Str. 9, D-60438 Frankfurt am Main, Germany
| | | | - Pavel Strop
- Rinat Labs, Pfizer Inc., 230 East Grand Ave, South San Francisco, CA 94080
| | - Robert Tampé
- Institute of Biochemistry, Biocenter, Goethe-University Frankfurt, Max-von-Laue-Str. 9, D-60438 Frankfurt am Main, Germany
| | - Robert H. Edwards
- Department of Physiology and Department of Neurology, University of California San Francisco, 600 16th Street, San Francisco, CA 94158
- California Institute of Quantitative Biosciences (QB3), University of California San Francisco, 600 16th Street, San Francisco, CA 94158
| | - Robert M. Stroud
- Department of Biochemistry and Biophysics, University of California San Francisco, 600 16th Street, San Francisco, CA 94158
- California Institute of Quantitative Biosciences (QB3), University of California San Francisco, 600 16th Street, San Francisco, CA 94158
| | - Charles S. Craik
- Department of Pharmaceutical Chemistry, University of California San Francisco, 600 16th Street, San Francisco, CA 94158
- California Institute of Quantitative Biosciences (QB3), University of California San Francisco, 600 16th Street, San Francisco, CA 94158
| | - Yifan Cheng
- The W.M. Keck Advanced Microscopy Laboratory, Department of Biochemistry and Biophysics, University of California San Francisco, 600 16th Street, San Francisco, CA 94158
- California Institute of Quantitative Biosciences (QB3), University of California San Francisco, 600 16th Street, San Francisco, CA 94158
| |
Collapse
|
31
|
Two Sec13p homologs, AtSec13A and AtSec13B, redundantly contribute to the formation of COPII transport vesicles in Arabidopsis thaliana. Biosci Biotechnol Biochem 2011; 75:1848-52. [PMID: 21897010 DOI: 10.1271/bbb.110331] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
COPII vesicles mediate protein transport from ER to Golgi. Sec13 makes up lattice structure with Sec31 to form COPII vesicles. We analyzed expression of two Arabidopsis thaliana Sec13 homologs, AtSec13A and AtSec13B. AtSec13A was expressed in most parts of seedlings, while AtSec13B was partially expressed. Interaction of AtSec13A or AtSec13B with Sec31 homolog was demonstrated by bimolecular fluorescence complementation (BiFC).
Collapse
|
32
|
Demmel L, Melak M, Kotisch H, Fendos J, Reipert S, Warren G. Differential selection of Golgi proteins by COPII Sec24 isoforms in procyclic Trypanosoma brucei. Traffic 2011; 12:1575-91. [PMID: 21801288 DOI: 10.1111/j.1600-0854.2011.01257.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The Sec24 subunit of the coat protein complex II (COPII) has been implicated in selecting newly synthesized cargo from the endoplasmic reticulum (ER) for delivery to the Golgi. The protozoan parasite, Trypanosoma brucei, contains two paralogs, TbSec24.1 and TbSec24.2, which were depleted using RNA interference in the insect form of the parasite. Depletion of either TbSec24.1 or TbSec24.2 resulted in growth arrest and modest inhibition of anterograde transport of the putative Golgi enzyme, TbGntB, and the secretory marker, BiPNAVRG-HA9. In contrast, depletion of TbSec24.1, but not TbSec24.2, led to reversible mislocalization of the Golgi stack proteins, TbGRASP and TbGolgin63. The latter accumulated in the ER. The localization of the COPI coatomer subunit, TbεCOP, and the trans Golgi network (TGN) protein, TbGRIP70, was largely unaffected, although the latter was preferentially lost from those Golgi that were not associated with the bilobe, a structure previously implicated in Golgi biogenesis. Together, these data suggest that TbSec24 paralogs can differentiate among proteins destined for the Golgi.
Collapse
Affiliation(s)
- Lars Demmel
- Max F. Perutz Laboratories, University of Vienna, Medical University of Vienna, Dr. Bohrgasse 9, A-1030 Vienna, Austria
| | | | | | | | | | | |
Collapse
|
33
|
García IA, Martinez HE, Alvarez C. Rab1b regulates COPI and COPII dynamics in mammalian cells. CELLULAR LOGISTICS 2011; 1:159-163. [PMID: 22279615 DOI: 10.4161/cl.1.4.18221] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Revised: 09/25/2011] [Accepted: 09/26/2011] [Indexed: 02/02/2023]
Abstract
Rabs GTPases are key regulatory factors that specifically associate to organelles that integrate membrane transport pathways. Rabs, through their interactions with diverse effector proteins, regulate the formation, movement, tethering and fusion of transport carriers (vesicles and/or tubules). The mammalian Rab1b GTPase is required for ER to Golgi transport and interacts with multiple effectors localized at the ER-Golgi interface. Here, we focus on interactions between Rab1b and effectors that play essential roles in COPII and COPI vesicle formation/function. Based on evidence to date, we propose a model of Rab1b action at the ER exit sites.
Collapse
Affiliation(s)
- Iris A García
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET); Departamento Bioquímica Clínica; Facultad de Ciencias Químicas; Universidad Nacional de Córdoba; Córdoba, Argentina
| | | | | |
Collapse
|
34
|
Suntio T, Shiryaev SA, Makarow M. ATPase activity of a yeast secretory glycoprotein allows ER exit during inactivation of COPII components Sec24p and Sec13p. Yeast 2011; 28:453-65. [PMID: 21446055 DOI: 10.1002/yea.1850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2010] [Accepted: 02/15/2011] [Indexed: 11/07/2022] Open
Abstract
Proteins exit the endoplasmic reticulum (ER) in vesicles pinching off from the membrane at sites covered by the COPII coat, which consists of Sec23/24p and Sec13/31p. We have shown that the glycoprotein Hsp150 exits the ER in the absence of Sec13p or any member of the Sec24p family. The determinant responsible for this resides in the C-terminal domain of Hsp150 (CTD). Here, A- and B-type Walker motifs were identified in the CTD. Authentic Hsp150 from the yeast culture medium, as well as Hsp150 and the CTD fragment produced in Escherichia coli, exhibited ATPase activity nearly three times higher than the published activity of the ER chaperone Kar2p/BiP. Deletion of the Walker motif, and a K335A mutation in it, abolished the ATPase activity. Hsp150 homologues Pir3p and Pir4p, differing in critical amino acids of the Walker motif, also lacked ATPase activity. Unexpectedly, inactivation of the ATPase activity blocked ER exit of Hsp150 in the absence of Sec24p or Sec13p function, whereas secretion in normal cells was not compromised. To our knowledge this is the first documentation of the ATPase activity of a protein serving an intracellular transport function.
Collapse
Affiliation(s)
- Taina Suntio
- Programme in Cellular Biotechnology, Institute of Biotechnology, University of Helsinki, Finland.
| | | | | |
Collapse
|
35
|
Maccioni HJF, Quiroga R, Spessott W. Organization of the synthesis of glycolipid oligosaccharides in the Golgi complex. FEBS Lett 2011; 585:1691-8. [PMID: 21420403 DOI: 10.1016/j.febslet.2011.03.030] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Revised: 03/11/2011] [Accepted: 03/14/2011] [Indexed: 11/28/2022]
Abstract
Glycolipids constitute a complex family of amphipathic molecules structurally characterized by a hydrophilic mono- or oligo-saccharide moiety linked to a hydrophobic ceramide moiety. Due to their asymmetric distribution in cell membranes, exposing the saccharide moiety to the extracytoplasmic side of the cell, glycolipids participate in a variety of cell-cell and cell-ligand interactions. Here we summarize aspects of the cell biology of the stepwise synthesis of the saccharide moiety in the Golgi complex of cells from vertebrates. In particular we refer to the participant glycosyltransferases, with emphasis on their trafficking along the secretory pathway, their retention and organization in the Golgi complex membranes and their dependence on the Golgi complex ultra structural organization for proper function.
Collapse
Affiliation(s)
- Hugo J F Maccioni
- Centro de Investigaciones en Química Biológica de Córdoba, CIQUIBIC (UNC-CONICET), Departamento de Química Biológica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina.
| | | | | |
Collapse
|
36
|
Kodera C, Yorimitsu T, Nakano A, Sato K. Sed4p stimulates Sar1p GTP hydrolysis and promotes limited coat disassembly. Traffic 2011; 12:591-9. [PMID: 21291503 DOI: 10.1111/j.1600-0854.2011.01173.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The coat protein complex II (COPII) generates transport vesicles that mediate protein export from the endoplasmic reticulum (ER). The first step of COPII vesicle formation involves conversion of Sar1p-GDP to Sar1p-GTP by guanine-nucleotide-exchange factor (GEF) Sec12p. In Saccharomyces cerevisiae, Sed4p is a structural homolog of Sec12p, but no GEF activity toward Sar1p has been found. Although the role of Sed4p in COPII vesicle formation is implied by the genetic interaction with SAR1, the molecular basis by which Sed4p contributes to this process is unclear. This study showed that the cytoplasmic domain of Sed4p preferentially binds the nucleotide-free form of Sar1p and that Sed4p binding stimulates both the intrinsic and Sec23p GTPase-activating protein (GAP)-accelerated GTPase activity of Sar1p. This stimulation of Sec23p GAP activity by Sed4p leads to accelerated dissociation of coat proteins from membranes. However, Sed4p binding to Sar1p occurs only when cargo is not associated with Sar1p. On the basis of these findings, Sed4p appears to accelerate the dissociation of the Sec23/24p coat from the membrane, but the effect is limited to Sar1p molecules that do not capture cargo protein. We speculate that this restricted coat disassembly may contribute to the concentration of specific cargo molecules into the COPII vesicles.
Collapse
Affiliation(s)
- Chie Kodera
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | | | | | | |
Collapse
|
37
|
Slavin I, García IA, Monetta P, Martinez H, Romero N, Alvarez C. Role of Rab1b in COPII dynamics and function. Eur J Cell Biol 2010; 90:301-11. [PMID: 21093099 DOI: 10.1016/j.ejcb.2010.10.001] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2010] [Revised: 10/04/2010] [Accepted: 10/04/2010] [Indexed: 12/27/2022] Open
Abstract
In eukaryotic cells, proteins destined for secretion are translocated into the endoplasmic reticulum (ER) and packaged into so-called COPII-coated vesicles. In the ER exit sites (ERES), COPII has the capacity of deforming the lipid bilayer, where it modulates the selective sorting and concentration of cargo proteins. In this study, we analyze the involvement of Rab1b in COPII dynamics and function by expressing either the Rab1b negative-mutant (Rab1N121I) or the Rab1b GTP restricted mutant (Rab1Q67L), or performing short interference RNA-based knockdown. We show that Rab1b interacts with the COPII components Sec23, Sec24 and Sec31 and that Rab1b inhibition changes the COPII phenotype. FRAP assays reveal that Rab1b modulates COPII association/dissociation kinetics at the ERES interface. Furthermore, Rab1b inhibition delays cargo sorting at the ER exit sites. We postulate that Rab1b is a key regulatory component of COPII dynamics and function.
Collapse
Affiliation(s)
- Ileana Slavin
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Departamento Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba 5000, Argentina
| | | | | | | | | | | |
Collapse
|
38
|
Ong YS, Tang BL, Loo LS, Hong W. p125A exists as part of the mammalian Sec13/Sec31 COPII subcomplex to facilitate ER-Golgi transport. ACTA ACUST UNITED AC 2010; 190:331-45. [PMID: 20679433 PMCID: PMC2922642 DOI: 10.1083/jcb.201003005] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
p125A is an accessory protein for COPII-mediated vesicle budding that links the Sec13/Sec31 and Sec23/24 subcomplexes. Coat protein II (COPII)–mediated export from the endoplasmic reticulum (ER) involves sequential recruitment of COPII complex components, including the Sar1 GTPase, the Sec23/Sec24 subcomplex, and the Sec13/Sec31 subcomplex. p125A was originally identified as a Sec23A-interacting protein. Here we demonstrate that p125A also interacts with the C-terminal region of Sec31A. The Sec31A-interacting domain of p125A is between residues 260–600, and is therefore a distinct domain from that required for interaction with Sec23A. Gel filtration and immunodepletion studies suggest that the majority of cytosolic p125A exists as a ternary complex with the Sec13/Sec31A subcomplex, suggesting that Sec 13, Sec31A, and p125A exist in the cytosol primarily as preassembled Sec13/Sec31A/p125A heterohexamers. Golgi morphology and protein export from the ER were affected in p125A-silenced cells. Our results suggest that p125A is part of the Sec13/Sec31A subcomplex and facilitates ER export in mammalian cells.
Collapse
Affiliation(s)
- Yan Shan Ong
- Cancer and Developmental Cell Biology Division, Institute of Molecular and Cell Biology, Singapore 138673, Singapore
| | | | | | | |
Collapse
|
39
|
Quintero CA, Giraudo CG, Villarreal M, Montich G, Maccioni HJF. Identification of a site in Sar1 involved in the interaction with the cytoplasmic tail of glycolipid glycosyltransferases. J Biol Chem 2010; 285:30340-6. [PMID: 20650895 DOI: 10.1074/jbc.m110.128868] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Glycolipid glycosyltransferases (GGT) are transported from the endoplasmic reticulum (ER) to the Golgi, their site of residence, via COPII vesicles. An interaction of a (R/K)X(R/K) motif at their cytoplasmic tail (CT) with Sar1 is critical for the selective concentration in the transport vesicles. In this work using computational docking, we identify three putative binding pockets in Sar1 (sites A, B, and C) involved in the interaction with the (R/K)X(R/K) motif. Sar1 mutants with alanine replacement of amino acids in site A were tested in vitro and in cells. In vitro, mutant versions showed a reduced ability to bind immobilized peptides with the CT sequence of GalT2. In cells, Sar1 mutants (Sar1(D198A)) specifically affect the exiting of GGT from the ER, resulting in an ER/Golgi concentration ratio favoring the ER. Neither the typical Golgi localization of GM130 nor the exiting and transport of the G protein of the vesicular stomatitis virus were affected. The protein kinase inhibitor H89 produced accumulation of Sec23, Sar1, and GalT2 at the ER exit sites; Sar1(D189A) also accumulated at these sites, but in this case GalT2 remained disperse along ER membranes. The results indicate that amino acids in site A of Sar1 are involved in the interaction with the CT of GGT for concentration at ER exiting sites.
Collapse
Affiliation(s)
- Cristián A Quintero
- Departamento de Química Biológica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, Centro de Investigaciones en Química Biológica de Córdoba, X5000HUA Córdoba, Argentina
| | | | | | | | | |
Collapse
|
40
|
Lee C, Goldberg J. Structure of coatomer cage proteins and the relationship among COPI, COPII, and clathrin vesicle coats. Cell 2010; 142:123-32. [PMID: 20579721 PMCID: PMC2943847 DOI: 10.1016/j.cell.2010.05.030] [Citation(s) in RCA: 148] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2010] [Revised: 04/07/2010] [Accepted: 04/22/2010] [Indexed: 10/19/2022]
Abstract
COPI-coated vesicles form at the Golgi apparatus from two cytosolic components, ARF G protein and coatomer, a heptameric complex that can polymerize into a cage to deform the membrane into a bud. Although coatomer shares a common evolutionary origin with COPII and clathrin vesicle coat proteins, the architectural relationship among the three cages is unclear. Strikingly, the alphabeta'-COP core of coatomer crystallizes as a triskelion in which three copies of a beta'-COP beta-propeller domain converge through their axial ends. We infer that the trimer constitutes the vertex of the COPI cage. Our model proposes that the COPI cage is intermediate in design between COPII and clathrin: COPI shares with clathrin an arrangement of three curved alpha-solenoid legs radiating from a common center, and COPI shares with COPII highly similar vertex interactions involving the axial ends of beta-propeller domains.
Collapse
Affiliation(s)
- Changwook Lee
- Howard Hughes Medical Institute, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10065, USA
| | | |
Collapse
|
41
|
Abstract
The absorption of dietary fat is of increasing concern given the rise of obesity not only in the United States but throughout the developed world. This review explores what happens to dietary fat within the enterocyte. Absorbed fatty acids and monoacylglycerols are required to be bound to intracellular proteins and/or to be rapidly converted to triacylglycerols to prevent cellular membrane disruption. The triacylglycerol produced at the level of the endoplasmic reticulum (ER) is either incorporated into prechylomicrons within the ER lumen or shunted to triacylglycerol storage pools. The prechylomicrons exit the ER in a specialized transport vesicle in the rate-limiting step in the intracellular transit of triacylglycerol across the enterocyte. The prechylomicrons are further processed in the Golgi and are transported to the basolateral membrane via a separate vesicular system for exocytosis into the intestinal lamina propria. Fatty acids and monoacylglycerols entering the enterocyte via the basolateral membrane are also incorporated into triacylglycerol, but the basolaterally entering lipid is much more likely to enter the triacylglycerol storage pool than the lipid entering via the apical membrane.
Collapse
Affiliation(s)
- Charles M Mansbach
- The University of Tennessee Health Science Center and the Veterans Administration Medical Center, Memphis, TN 38163, USA.
| | | |
Collapse
|
42
|
|
43
|
Budnik A, Stephens DJ. ER exit sites--localization and control of COPII vesicle formation. FEBS Lett 2009; 583:3796-803. [PMID: 19850039 DOI: 10.1016/j.febslet.2009.10.038] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2009] [Revised: 10/13/2009] [Accepted: 10/15/2009] [Indexed: 11/15/2022]
Abstract
The first membrane trafficking step in the biosynthetic secretory pathway, the export of proteins and lipids from the endoplasmic reticulum (ER), is mediated by COPII-coated vesicles. In mammalian cells, COPII vesicle budding occurs at specialized sites on the ER, the so-called transitional ER (tER). Here, we discuss aspects of the formation and maintenance of these sites, the mechanisms by which cargo becomes segregated within them, and the propagation of ER exit sites (ERES) during cell division. All of these features are inherently linked to the formation, maintenance and function of the Golgi apparatus underlining the importance of ERES to Golgi function and more widely in terms of intracellular organization and cellular function.
Collapse
Affiliation(s)
- Annika Budnik
- Cell Biology Laboratories, Department of Biochemistry, University of Bristol, School of Medical Sciences, University Walk, Bristol BS8 1TD, United Kingdom
| | | |
Collapse
|
44
|
Structure of a trimeric nucleoporin complex reveals alternate oligomerization states. Proc Natl Acad Sci U S A 2009; 106:17693-8. [PMID: 19805193 DOI: 10.1073/pnas.0909373106] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The heptameric Nup84 complex constitutes an evolutionarily conserved building block of the nuclear pore complex. Here, we present the crystal structure of the heterotrimeric Sec13 x Nup145C x Nup84 complex, the centerpiece of the heptamer, at 3.2-A resolution. Nup84 forms a U-shaped alpha-helical solenoid domain, topologically similar to two other members of the heptamer, Nup145C and Nup85. The interaction between Nup84 and Nup145C is mediated via a hydrophobic interface located in the kink regions of the two solenoids that is reinforced by additional interactions of two long Nup84 loops. The Nup84 binding site partially overlaps with the homo-dimerization interface of Nup145C, suggesting competing binding events. Fitting of the elongated Z-shaped heterotrimer into electron microscopy (EM) envelopes of the heptamer indicates that structural changes occur at the Nup145C x Nup84 interface. Docking the crystal structures of all heptamer components into the EM envelope constitutes a major advance toward the completion of the structural characterization of the Nup84 complex.
Collapse
|
45
|
Xie Z, Nair U, Geng J, Szefler MB, Rothman ED, Klionsky DJ. Indirect estimation of the area density of Atg8 on the phagophore. Autophagy 2009; 5:217-20. [PMID: 19088501 DOI: 10.4161/auto.5.2.7201] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Atg8 is a ubiquitin-like protein that controls the expansion of the phagophore during autophagosome formation. It is recruited to the phagophore during the expansion stage and released upon the completion of the autophagosome. One possible model explaining the function of Atg8 is that it acts as an adaptor of a coat complex. Here, we tested the coat-adaptor model by estimating the area density of Atg8 molecules on the phagophore. We developed a computational process to simulate the random sectioning of vesicles heterogeneous in size. This method can be applied to estimate the original sizes of intracellular vesicles from sizes of their random sections obtained through transmission electron microscopy. Using this method, we found that the estimated area density of Atg8 is comparable with that of proteins that form the COPII coat.
Collapse
Affiliation(s)
- Zhiping Xie
- Life Sciences Institute and Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109-2216, USA
| | | | | | | | | | | |
Collapse
|
46
|
Debler EW, Ma Y, Seo HS, Hsia KC, Noriega TR, Blobel G, Hoelz A. A fence-like coat for the nuclear pore membrane. Mol Cell 2009; 32:815-26. [PMID: 19111661 DOI: 10.1016/j.molcel.2008.12.001] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2008] [Revised: 11/21/2008] [Accepted: 12/02/2008] [Indexed: 01/11/2023]
Abstract
We recently proposed a cylindrical coat for the nuclear pore membrane in the nuclear pore complex (NPC). This scaffold is generated by multiple copies of seven nucleoporins. Here, we report three crystal structures of the nucleoporin pair Seh1*Nup85, which is part of the coat cylinder. The Seh1*Nup85 assembly bears resemblance in its shape and dimensions to that of another nucleoporin pair, Sec13*Nup145C. Furthermore, the Seh1*Nup85 structures reveal a hinge motion that may facilitate conformational changes in the NPC during import of integral membrane proteins and/or during nucleocytoplasmic transport. We propose that Seh1*Nup85 and Sec13*Nup145C form 16 alternating, vertical rods that are horizontally linked by the three remaining nucleoporins of the coat cylinder. Shared architectural and mechanistic principles with the COPII coat indicate a common evolutionary origin and support the notion that the NPC coat represents another class of membrane coats.
Collapse
Affiliation(s)
- Erik W Debler
- Laboratory of Cell Biology, Howard Hughes Medical Institute, The Rockefeller University, 1230 York Avenue, New York, NY 10065, USA
| | | | | | | | | | | | | |
Collapse
|
47
|
Field MC, Lumb JH, Adung'a VO, Jones NG, Engstler M. Chapter 1 Macromolecular Trafficking and Immune Evasion in African Trypanosomes. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2009; 278:1-67. [DOI: 10.1016/s1937-6448(09)78001-3] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
48
|
Castillon GA, Watanabe R, Taylor M, Schwabe TME, Riezman H. Concentration of GPI-anchored proteins upon ER exit in yeast. Traffic 2008; 10:186-200. [PMID: 19054390 DOI: 10.1111/j.1600-0854.2008.00857.x] [Citation(s) in RCA: 134] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Previous biochemical work has revealed two parallel routes of exit from the endoplasmic reticulum (ER) in the yeast Saccharomyces cerevisiae, one seemingly specific for glycosyl-phosphatidylinositol (GPI)-anchored proteins. Using the coat protein II (COPII) mutant sec31-1, we visualized ER exit sites (ERES) and identified three distinct ERES populations in vivo. One contains glycosylated pro-alpha-factor, the second contains the GPI-anchored proteins Cwp2p, Ccw14p and Tos6p and the third is enriched with the hexose transporter, Hxt1p. Concentration of GPI-anchored proteins prior to budding requires anchor remodeling, and Hxt1p incorporation into ERES requires the COPII components Sec12p and Sec16p. Additionally, we have found that GPI-anchored protein ER exit is controlled by the p24 family member Emp24p, whereas ER export of most transmembrane proteins requires the Cornichon homologue Erv14p.
Collapse
Affiliation(s)
- Guillaume A Castillon
- Department of Biochemistry, University of Geneva, Sciences II, 30 quai Ernest Ansermet, CH-1211 Geneva, Switzerland
| | | | | | | | | |
Collapse
|
49
|
Abstract
The secretion of vesicles for intracellular transport often relies on the aggregation of specialized membrane-bound proteins into a coat able to curve cell membranes. The nucleation and growth of a protein coat is a kinetic process that competes with the energy-consuming turnover of coat components between the membrane and the cytosol. We propose a generic kinetic description of coat assembly and the formation of coated vesicles and discuss its implication to the dynamics of COP vesicles that traffic within the Golgi and with the endoplasmic reticulum. We show that stationary coats of fixed area emerge from the competition between coat growth and the recycling of coat components, in a fashion resembling the treadmilling of cytoskeletal filaments. We further show that the turnover of coat components allows for a highly sensitive switching mechanism between a quiescent and a vesicle producing membrane, upon a slowing down of the exchange kinetics. We claim that the existence of this switching behavior, also triggered by factors, such as the presence of cargo and variation of the membrane mechanical tension, allows for efficient regulation of vesicle secretion. We propose a model, supported by different experimental observations, in which vesiculation of secretory membranes is impaired by the energy-consuming desorption of coat proteins, until the presence of cargo or other factors triggers a dynamical switch into a vesicle producing state.
Collapse
|
50
|
Protein interactions: analysis using allele libraries. ADVANCES IN BIOCHEMICAL ENGINEERING/BIOTECHNOLOGY 2008; 110:47-66. [PMID: 18528666 DOI: 10.1007/10_2008_102] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Interaction defective alleles (IDAs) are alleles that contain mutations affecting their ability to interact with their wild type binding partners. The locations of the mutations may lead to the identification of protein interaction domains and interaction interfaces. IDAs may also distinguish different binding interfaces of multidomain proteins that are part of large complexes, thus shedding light on large protein structures that have yet to be determined. IDAs may also be used in conjunction with RNAi to dissect protein interaction networks. Here, the wild type allele is knocked down and replaced with an IDA that has lost the ability to interact with a specific binding partner. As a result, interactions are disrupted rather than knocking out the entire gene. Thus, IDAs have the potential to be extremely valuable tools in protein interaction network analysis. IDAs can be isolated by reverse two-hybrid analysis, which was demonstrated over a decade ago, but high background levels caused by truncated IDAs have prevented its widespread adoption. We recently described a novel method for full-length allele library generation that eliminates this background and increases the efficiency of the reverse two-hybrid protocol (and IDA isolation) significantly. Here we discuss our strategy for allele library generation, the potential uses of IDAs as outlined above, and additional applications of allele libraries.
Collapse
|