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Jadhav R, Mach RL, Mach-Aigner AR. Protein secretion and associated stress in industrially employed filamentous fungi. Appl Microbiol Biotechnol 2024; 108:92. [PMID: 38204136 PMCID: PMC10781871 DOI: 10.1007/s00253-023-12985-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 12/21/2023] [Accepted: 12/22/2023] [Indexed: 01/12/2024]
Abstract
Application of filamentous fungi for the production of commercial enzymes such as amylase, cellulase, or xylanase is on the rise due to the increasing demand to degrade several complex carbohydrates as raw material for biotechnological processes. Also, protein production by fungi for food and feed gains importance. In any case, the protein production involves both cellular synthesis and secretion outside of the cell. Unfortunately, the secretion of proteins or enzymes can be hampered due to accumulation of unfolded or misfolded proteins in the endoplasmic reticulum (ER) as a result of too high synthesis of enzymes or (heterologous) protein expression. To cope with this ER stress, the cell generates a response known as unfolded protein response (UPR). Even though this mechanism should re-establish the protein homeostasis equivalent to a cell under non-stress conditions, the enzyme expression might still suffer from repression under secretory stress (RESS). Among eukaryotes, Saccharomyces cerevisiae is the only fungus, which is studied quite extensively to unravel the UPR pathway. Several homologs of the proteins involved in this signal transduction cascade are also found in filamentous fungi. Since RESS seems to be absent in S. cerevisiae and was only reported in Trichoderma reesei in the presence of folding and glycosylation inhibitors such as dithiothreitol and tunicamycin, more in-depth study about this mechanism, specifically in filamentous fungi, is the need of the hour. Hence, this review article gives an overview on both, protein secretion and associated stress responses in fungi. KEY POINTS: • Enzymes produced by filamentous fungi are crucial in industrial processes • UPR mechanism is conserved among many fungi, but mediated by different proteins • RESS is not fully understood or studied in industrially relevant filamentous fungi.
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Affiliation(s)
- Reshma Jadhav
- Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Gumpendorfer Str. 1a, A-1060, Vienna, Austria
- Christian Doppler Laboratory for Optimized Expression of Carbohydrate-Active Enzymes, Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Gumpendorfer Str. 1a, A-1060, Vienna, Austria
| | - Robert L Mach
- Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Gumpendorfer Str. 1a, A-1060, Vienna, Austria
| | - Astrid R Mach-Aigner
- Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Gumpendorfer Str. 1a, A-1060, Vienna, Austria.
- Christian Doppler Laboratory for Optimized Expression of Carbohydrate-Active Enzymes, Institute of Chemical, Environmental and Bioscience Engineering, TU Wien, Gumpendorfer Str. 1a, A-1060, Vienna, Austria.
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2
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Chung KP, Frieboese D, Waltz F, Engel BD, Bock R. Identification and characterization of the COPII vesicle-forming GTPase Sar1 in Chlamydomonas. PLANT DIRECT 2024; 8:e614. [PMID: 38887666 PMCID: PMC11180857 DOI: 10.1002/pld3.614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Accepted: 05/29/2024] [Indexed: 06/20/2024]
Abstract
Eukaryotic cells are highly compartmentalized, requiring elaborate transport mechanisms to facilitate the movement of proteins between membrane-bound compartments. Most proteins synthesized in the endoplasmic reticulum (ER) are transported to the Golgi apparatus through COPII-mediated vesicular trafficking. Sar1, a small GTPase that facilitates the formation of COPII vesicles, plays a critical role in the early steps of this protein secretory pathway. Sar1 was characterized in yeast, animals and plants, but no Sar1 homolog has been identified and functionally analyzed in algae. Here we identified a putative Sar1 homolog (CrSar1) in the model green alga Chlamydomonas reinhardtii through amino acid sequence similarity. We employed site-directed mutagenesis to generate a dominant-negative mutant of CrSar1 (CrSar1DN). Using protein secretion assays, we demonstrate the inhibitory effect of CrSar1DN on protein secretion. However, different from previously studied organisms, ectopic expression of CrSar1DN did not result in collapse of the ER-Golgi interface in Chlamydomonas. Nonetheless, our data suggest a largely conserved role of CrSar1 in the ER-to-Golgi protein secretory pathway in green algae.
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Affiliation(s)
- Kin Pan Chung
- Max‐Planck‐Institut für Molekulare PflanzenphysiologiePotsdamGermany
| | - Daniel Frieboese
- Max‐Planck‐Institut für Molekulare PflanzenphysiologiePotsdamGermany
| | | | | | - Ralph Bock
- Max‐Planck‐Institut für Molekulare PflanzenphysiologiePotsdamGermany
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3
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Liu X, Li Y, Gao Y, El Wakil A, Moussian B, Zhang J. RNA interference-mediated silencing of coat protein II (COPII) genes affects the gut homeostasis and cuticle development in Locusta migratoria. Int J Biol Macromol 2024; 266:131137. [PMID: 38537854 DOI: 10.1016/j.ijbiomac.2024.131137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 03/08/2024] [Accepted: 03/23/2024] [Indexed: 04/06/2024]
Abstract
The coat protein II (COPII) complex consists of five primary soluble proteins, namely the small GTP-binding protein Sar1, the inner coat Sec23/Sec24 heterodimers, and the outer coat Sec13/Sec31 heterotetramers. COPII is essential for cellular protein and lipid trafficking through cargo sorting and vesicle formation at the endoplasmic reticulum. However, the roles of COPII assembly genes remain unknown in insects. In present study, we identified five COPII assembly genes (LmSar1, LmSec23, LmSec24, LmSec13 and LmSec31) in Locusta migratoria. RT-qPCR results revealed that these genes showed different expression patterns in multiple tissues and developmental days of fifth-instar nymphs. Injection of double-stranded RNA against each LmCOPII gene induced a high RNAi efficiency, and considerably suppressed feeding, and increased mortality to 100 %. Results from the micro-sectioning and hematoxylin-eosin staining of midguts showed that the brush border was severely damaged and the number of columnar cells was significantly reduced in dsLmCOPII-injected nymphs, as compared with the control. The dilated endoplasmic reticulum phenotype of columnar cells was observed by transmission electron microscopy. RT-qPCR results further indicated that silencing any of the five genes responsible for COPII complex assembly repressed the expression of genes involved in insulin/mTOR-associated nutritional pathway. Therefore, COPII assembly genes could be promising RNAi targets for insect pest management by disrupting gut and cuticle development.
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Affiliation(s)
- Xiaojian Liu
- Shanxi Key Laboratory of Nucleic Acid Biopesticides, Research Institute of Applied Biology, Shanxi University, Taiyuan, Shanxi 030006, China
| | - Yao Li
- Shanxi Key Laboratory of Nucleic Acid Biopesticides, Research Institute of Applied Biology, Shanxi University, Taiyuan, Shanxi 030006, China
| | - Ya Gao
- Shanxi Key Laboratory of Nucleic Acid Biopesticides, Research Institute of Applied Biology, Shanxi University, Taiyuan, Shanxi 030006, China
| | - Abeer El Wakil
- Faculty of Education, Department of Biological and Geological Sciences, Alexandria University, Alexandria, Egypt
| | - Bernard Moussian
- INRAE, CNRS, Université Côte d'Azur, Institut Sophia Agrobiotech, Sophia Antipolis, France
| | - Jianzhen Zhang
- Shanxi Key Laboratory of Nucleic Acid Biopesticides, Research Institute of Applied Biology, Shanxi University, Taiyuan, Shanxi 030006, China.
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4
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Chen J, Fang Z, Luo Q, Wang X, Warda M, Das A, Oldoni F, Luo F. Unlocking the mysteries of VLDL: exploring its production, intracellular trafficking, and metabolism as therapeutic targets. Lipids Health Dis 2024; 23:14. [PMID: 38216994 PMCID: PMC10785355 DOI: 10.1186/s12944-023-01993-y] [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: 09/04/2023] [Accepted: 12/26/2023] [Indexed: 01/14/2024] Open
Abstract
Reducing circulating lipid levels is the centerpiece of strategies for preventing and treating atherosclerotic cardiovascular disease (ASCVD). Despite many available lipid-lowering medications, a substantial residual cardiovascular risk remains. Current clinical guidelines focus on plasma levels of low-density lipoprotein (LDL). Recent attention has been given to very low-density lipoprotein (VLDL), the precursor to LDL, and its role in the development of coronary atherosclerosis. Preclinical investigations have revealed that interventions targeting VLDL production or promoting VLDL metabolism, independent of the LDL receptor, can potentially decrease cholesterol levels and provide therapeutic benefits. Currently, methods, such as mipomersen, lomitapide, and ANGPTL3 inhibitors, are used to reduce plasma cholesterol and triglyceride levels by regulating the lipidation, secretion, and metabolism of VLDL. Targeting VLDL represents an avenue for new lipid-lowering strategies. Interventions aimed at reducing VLDL production or enhancing VLDL metabolism, independent of the LDL receptor, hold promise for lowering cholesterol levels and providing therapeutic benefits beyond LDL in the management of ASCVD.
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Affiliation(s)
- Jingfei Chen
- Reproductive Medicine Center, Department of Obstetrics and Gynecology, Research Institute of Blood Lipid and Atherosclerosis, The Second Xiangya Hospital, Central South University, Changsha, Hunan, 410011, China
| | - Zhenfei Fang
- Research Institute of Blood Lipid and Atherosclerosis, the Second Xiangya Hospital, Central South University, Changsha, Hunan, 410011, China
- Department of Cardiovascular Medicine, The Second Xiangya Hospital, Central South University, Changsha, Hunan, 410011, China
| | - Qin Luo
- Research Institute of Blood Lipid and Atherosclerosis, the Second Xiangya Hospital, Central South University, Changsha, Hunan, 410011, China
- Department of Cardiovascular Medicine, The Second Xiangya Hospital, Central South University, Changsha, Hunan, 410011, China
| | - Xiao Wang
- State Key Laboratory of Membrane Biology, Peking University, Beijing, 100871, China
| | - Mohamad Warda
- Department of Biochemistry and Molecular Biology, Faculty of Veterinary Medicine, Cairo University, Giza, 12211, Egypt
- Department of Physiology, Faculty of Veterinary Medicine, Ataturk University, Erzurum, 25240, Turkey
| | - Avash Das
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, 02215-5400, USA
| | - Federico Oldoni
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Fei Luo
- Research Institute of Blood Lipid and Atherosclerosis, the Second Xiangya Hospital, Central South University, Changsha, Hunan, 410011, China.
- Department of Cardiovascular Medicine, The Second Xiangya Hospital, Central South University, Changsha, Hunan, 410011, China.
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Land R, Fetter R, Liang X, Tzeng CP, Taylor CA, Shen K. Endoplasmic Reticulum Exit Sites scale with somato-dendritic size in neurons. Mol Biol Cell 2023; 34:ar106. [PMID: 37556208 PMCID: PMC10559313 DOI: 10.1091/mbc.e23-03-0090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 07/10/2023] [Accepted: 08/02/2023] [Indexed: 08/11/2023] Open
Abstract
Nervous systems exhibit dramatic diversity in cell morphology and size. How neurons regulate their biosynthetic and secretory machinery to support such diversity is not well understood. Endoplasmic reticulum exit sites (ERESs) are essential for maintaining secretory flux, and are required for normal dendrite development, but how neurons of different size regulate secretory capacity remains unknown. In Caenorhabditis elegans, we find that the ERES number is strongly correlated with the size of a neuron's dendritic arbor. The elaborately branched sensory neuron, PVD, has especially high ERES numbers. Asymmetric cell division provides PVD with a large initial cell size critical for rapid establishment of PVD's high ERES number before neurite outgrowth, and these ERESs are maintained throughout development. Maintenance of ERES number requires the cell fate transcription factor MEC-3, C. elegans TOR (ceTOR/let-363), and nutrient availability, with mec-3 and ceTOR/let-363 mutant PVDs both displaying reductions in ERES number, soma size, and dendrite size. Notably, mec-3 mutant animals exhibit reduced expression of a ceTOR/let-363 reporter in PVD, and starvation reduces ERES number and somato-dendritic size in a manner genetically redundant with ceTOR/let-363 perturbation. Our data suggest that both asymmetric cell division and nutrient sensing pathways regulate secretory capacities to support elaborate dendritic arbors.
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Affiliation(s)
- Ruben Land
- Department of Biology, Stanford University, Stanford, CA 94305
- Neurosciences IDP, Stanford University, Stanford, CA 94305
| | - Richard Fetter
- Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305
| | - Xing Liang
- Department of Biology, Stanford University, Stanford, CA 94305
| | - Christopher P. Tzeng
- Department of Biology, Stanford University, Stanford, CA 94305
- Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305
| | - Caitlin A. Taylor
- Department of Biology, Stanford University, Stanford, CA 94305
- Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305
| | - Kang Shen
- Department of Biology, Stanford University, Stanford, CA 94305
- Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305
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6
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Yorimitsu T, Sato K. Sec16 and Sed4 interdependently function as interaction and localization partners at ER exit sites. J Cell Sci 2023; 136:308925. [PMID: 37158682 PMCID: PMC10184828 DOI: 10.1242/jcs.261094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 04/06/2023] [Indexed: 05/10/2023] Open
Abstract
COPII proteins assemble at ER exit sites (ERES) to form transport carriers. The initiation of COPII assembly in the yeast Saccharomyces cerevisiae is triggered by the ER membrane protein Sec12. Sec16, which plays a critical role in COPII organization, localizes to ERES independently of Sec12. However, the mechanism underlying Sec16 localization is poorly understood. Here, we show that a Sec12 homolog, Sed4, is concentrated at ERES and mediates ERES localization of Sec16. We found that the interaction between Sec16 and Sed4 ensures their correct localization to ERES. Loss of the interaction with Sec16 leads to redistribution of Sed4 from the ERES specifically to high-curvature ER areas, such as the tubules and edges of the sheets. The luminal domain of Sed4 mediates this distribution, which is required for Sed4, but not for Sec16, to be concentrated at ERES. We further show that the luminal domain and its O-mannosylation are involved in the self-interaction of Sed4. Our findings provide insight into how Sec16 and Sed4 function interdependently at ERES.
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Affiliation(s)
- Tomohiro Yorimitsu
- Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Tokyo 153-8902, Japan
| | - Ken Sato
- Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Tokyo 153-8902, Japan
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7
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Van der Verren SE, Zanetti G. The small GTPase Sar1, control centre of COPII trafficking. FEBS Lett 2023; 597:865-882. [PMID: 36737236 DOI: 10.1002/1873-3468.14595] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 01/23/2023] [Accepted: 01/25/2023] [Indexed: 02/05/2023]
Abstract
Sar1 is a small GTPase of the ARF family. Upon exchange of GDP for GTP, Sar1 associates with the endoplasmic reticulum (ER) membrane and recruits COPII components, orchestrating cargo concentration and membrane deformation. Many aspects of the role of Sar1 and regulation of its GTP cycle remain unclear, especially as complexity increases in higher organisms that secrete a wider range of cargoes. This review focusses on the regulation of GTP hydrolysis and its role in coat assembly, as well as the mechanism of Sar1-induced membrane deformation and scission. Finally, we highlight the additional specialisation in higher eukaryotes and the outstanding questions on how Sar1 functions are orchestrated.
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Affiliation(s)
| | - Giulia Zanetti
- Institute of Structural and Molecular Biology, Birkbeck College London, UK
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8
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Tapia D, Cavieres VA, Burgos PV, Cancino J. Impact of interorganelle coordination between the conventional early secretory pathway and autophagy in cellular homeostasis and stress response. Front Cell Dev Biol 2023; 11:1069256. [PMID: 37152281 PMCID: PMC10160633 DOI: 10.3389/fcell.2023.1069256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 04/07/2023] [Indexed: 05/09/2023] Open
Abstract
The conventional early secretory pathway and autophagy are two essential interconnected cellular processes that are crucial for maintaining cellular homeostasis. The conventional secretory pathway is an anabolic cellular process synthesizing and delivering proteins to distinct locations, including different organelles, the plasma membrane, and the extracellular media. On the other hand, autophagy is a catabolic cellular process that engulfs damaged organelles and aberrant cytosolic constituents into the double autophagosome membrane. After fusion with the lysosome and autolysosome formation, this process triggers digestion and recycling. A growing list of evidence indicates that these anabolic and catabolic processes are mutually regulated. While knowledge about the molecular actors involved in the coordination and functional cooperation between these two processes has increased over time, the mechanisms are still poorly understood. This review article summarized and discussed the most relevant evidence about the key molecular players implicated in the interorganelle crosstalk between the early secretory pathway and autophagy under normal and stressful conditions.
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Affiliation(s)
- Diego Tapia
- Cell Biology of Interorganelle Signaling Laboratory, Centro de Biología Celular y Biomedicina (CEBICEM), Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| | - Viviana A. Cavieres
- Organelle Phagy Lab, Centro de Biología Celular y Biomedicina (CEBICEM), Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
| | - Patricia V. Burgos
- Organelle Phagy Lab, Centro de Biología Celular y Biomedicina (CEBICEM), Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
- Centro Ciencia & Vida, Fundación Ciencia & Vida, Santiago, Chile
| | - Jorge Cancino
- Cell Biology of Interorganelle Signaling Laboratory, Centro de Biología Celular y Biomedicina (CEBICEM), Facultad de Medicina y Ciencia, Universidad San Sebastián, Santiago, Chile
- *Correspondence: Jorge Cancino,
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9
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Sar1 Interacts with Sec23/Sec24 and Sec13/Sec31 Complexes: Insight into Its Involvement in the Assembly of Coat Protein Complex II in the Microsporidian Nosema bombycis. Microbiol Spectr 2022; 10:e0071922. [PMID: 36301095 PMCID: PMC9769691 DOI: 10.1128/spectrum.00719-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Microsporidia, as unicellular eukaryotes, also have an endomembrane system for transporting proteins, which is essentially similar to those of other eukaryotes. In eukaryotes, coat protein complex II (COPII) consists of Sar1, Sec23, Sec24, Sec13, and Sec31 and mediates protein transport from the endoplasmic reticulum (ER) to the Golgi apparatus. Sar1 is the central player in the regulation of coat protein complex II vesicle formation in the endoplasmic reticulum. In this study, we successfully cloned the NbSar1, NbSec23-1, NbSec23-2, NbSec24-1, NbSec24-2, NbSec13, NbSec31-1, and NbSec31-2 genes and prepared NbSar1 polyclonal antibody. We found that NbSar1 was localized mainly in the perinuclear cytoplasm of Nosema bombycis by immunofluorescence analysis (IFA). Yeast two-hybrid assays demonstrated that NbSar1 interacts with NbSec23-2, NbSec23-2 interacts with NbSec24-1 or NbSec24-2, NbSec23-1 interacts with NbSec31, and NbSec31 interacts with NbSec13. Moreover, the silencing of NbSar1 by RNA interference resulted in the aberrant expression of NbSar1, NbSec23-1, NbSec24-1, NbSec24-2, NbSec13, NbSec31-1, and NbSec31-2 and significantly inhibited the proliferation of N. bombycis. Altogether, these findings indicated that the subunits of coat protein complex II work together to perform functions in the proliferation of N. bombycis and that NbSar1 may play a crucial role in coat protein complex II vesicle formation. IMPORTANCE As eukaryotes, microsporidia have retained the endomembrane system for transporting and sorting proteins throughout their evolution. Whether the microsporidia form coat protein complex II (COPII) vesicles to transport cargo proteins and whether they play other roles besides cargo transport are not fully explained at present. Our results showed that NbSar1, NbSec23-1/NbSec23-2, NbSec24-1/NbSec24-2, NbSec13, and NbSec31 might be assembled to form COPII in the ER of N. bombycis, and the functions of COPII are also closely related to the proliferation of N. bombycis, this may be a new target for the prevention of pébrine disease of the silkworm.
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Ren Y, Wang Y, Zhang Y, Pan T, Duan E, Bao X, Zhu J, Teng X, Zhang P, Gu C, Dong H, Wang F, Wang Y, Bao Y, Wang Y, Wan J. Endomembrane-mediated storage protein trafficking in plants: Golgi-dependent or Golgi-independent? FEBS Lett 2022; 596:2215-2230. [PMID: 35615915 DOI: 10.1002/1873-3468.14374] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 04/18/2022] [Accepted: 04/27/2022] [Indexed: 11/11/2022]
Abstract
Seed storage proteins (SSPs) accumulated within plant seeds constitute the major protein nutrition sources for human and livestock. SSPs are synthesized on the endoplasmic reticulum (ER) and then deposited in plant-specific protein bodies (PBs), including ER-derived PBs and protein storage vacuoles (PSVs). Plant seeds have evolved a distinct endomembrane system to accomplish SSP transport. There are two distinct types of trafficking pathways contributing to SSP delivery to PSVs, one Golgi-dependent and the other Golgi-independent. In recent years, molecular, genetic and biochemical studies have shed light on the complex network controlling SSP trafficking, to which both evolutionarily conserved molecular machineries and plant-unique regulators contribute. In this review, we discuss current knowledge of PB biogenesis and endomembrane-mediated SSP transport, focusing on ER export and post-Golgi traffic. These knowledges support a dominant role for the Golgi-dependent pathways in SSP transport in Arabidopsis and rice. In addition, we describe cutting-edge strategies to dissect the endomembrane trafficking system in plant seeds to advance the field.
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Affiliation(s)
- Yulong Ren
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Yongfei Wang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yu Zhang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Tian Pan
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Erchao Duan
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Xiuhao Bao
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Jianping Zhu
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Xuan Teng
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Pengcheng Zhang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Chuanwei Gu
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Hui Dong
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Fan Wang
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Yunlong Wang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yiqun Bao
- College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, China
| | - Yihua Wang
- State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
| | - Jianmin Wan
- National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.,State Key Laboratory for Crop Genetics and Germplasm Enhancement, Jiangsu Plant Gene Engineering Research Center, Nanjing Agricultural University, Nanjing, 210095, China
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11
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Nakano A. The Golgi Apparatus and its Next-Door Neighbors. Front Cell Dev Biol 2022; 10:884360. [PMID: 35573670 PMCID: PMC9096111 DOI: 10.3389/fcell.2022.884360] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Accepted: 03/28/2022] [Indexed: 12/20/2022] Open
Abstract
The Golgi apparatus represents a central compartment of membrane traffic. Its apparent architecture, however, differs considerably among species, from unstacked and scattered cisternae in the budding yeast Saccharomyces cerevisiae to beautiful ministacks in plants and further to gigantic ribbon structures typically seen in mammals. Considering the well-conserved functions of the Golgi, its fundamental structure must have been optimized despite seemingly different architectures. In addition to the core layers of cisternae, the Golgi is usually accompanied by next-door compartments on its cis and trans sides. The trans-Golgi network (TGN) can be now considered as a compartment independent from the Golgi stack. On the cis side, the intermediate compartment between the ER and the Golgi (ERGIC) has been known in mammalian cells, and its functional equivalent is now suggested for yeast and plant cells. High-resolution live imaging is extremely powerful for elucidating the dynamics of these compartments and has revealed amazing similarities in their behaviors, indicating common mechanisms conserved along the long course of evolution. From these new findings, I would like to propose reconsideration of compartments and suggest a new concept to describe their roles comprehensively around the Golgi and in the post-Golgi trafficking.
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12
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Krasovec G, Hozumi A, Yoshida T, Obita T, Hamada M, Shiraishi A, Satake H, Horie T, Mori H, Sasakura Y. d-Serine controls epidermal vesicle release via NMDA receptor, allowing tissue migration during the metamorphosis of the chordate Ciona. SCIENCE ADVANCES 2022; 8:eabn3264. [PMID: 35275721 PMCID: PMC8916719 DOI: 10.1126/sciadv.abn3264] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 01/20/2022] [Indexed: 05/26/2023]
Abstract
d-Serine, a free amino acid synthesized by serine racemase, is a coagonist of N-methyl-d-aspartate-type glutamate receptor (NMDAR). d-Serine in the mammalian central nervous system modulates glutamatergic transmission. Functions of d-serine in mammalian peripheral tissues such as skin have also been described. However, d-serine's functions in nonmammals are unclear. Here, we characterized d-serine-dependent vesicle release from the epidermis during metamorphosis of the tunicate Ciona. d-Serine leads to the formation of a pocket that facilitates the arrival of migrating tissue during tail regression. NMDAR is the receptor of d-serine in the formation of the epidermal pocket. The epidermal pocket is formed by the release of epidermal vesicles' content mediated by d-serine/NMDAR. This mechanism is similar to observations of keratinocyte vesicle exocytosis in mammalian skin. Our findings provide a better understanding of the maintenance of epidermal homeostasis in animals and contribute to further evolutionary perspectives of d-amino acid function among metazoans.
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Affiliation(s)
- Gabriel Krasovec
- Shimoda Marine Research Center, University of Tsukuba, Shizuoka, Japan
- Center for Chromosome Biology, National University of Ireland Galway, Galway, Ireland
| | - Akiko Hozumi
- Shimoda Marine Research Center, University of Tsukuba, Shizuoka, Japan
| | - Tomoyuki Yoshida
- Department of Molecular Neuroscience, Faculty of Medicine, University of Toyama, Toyama, Japan
| | - Takayuki Obita
- Faculty of Pharmaceutical Sciences, University of Toyama, Toyama, Japan
| | - Mayuko Hamada
- Ushimado Marine Institute, Okayama University, Okayama, Japan
| | - Akira Shiraishi
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Osaka, Japan
| | - Honoo Satake
- Bioorganic Research Institute, Suntory Foundation for Life Sciences, Osaka, Japan
| | - Takeo Horie
- Shimoda Marine Research Center, University of Tsukuba, Shizuoka, Japan
| | - Hisashi Mori
- Department of Molecular Neuroscience, Faculty of Medicine, University of Toyama, Toyama, Japan
| | - Yasunori Sasakura
- Shimoda Marine Research Center, University of Tsukuba, Shizuoka, Japan
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13
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Chang M, Wu SZ, Ryken SE, O’Sullivan JE, Bezanilla M. COPII Sec23 proteins form isoform-specific endoplasmic reticulum exit sites with differential effects on polarized growth. THE PLANT CELL 2022; 34:333-350. [PMID: 34534343 PMCID: PMC8846183 DOI: 10.1093/plcell/koab229] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 09/07/2021] [Indexed: 05/04/2023]
Abstract
Coat Protein complex II (COPII), a coat protein complex that forms vesicles on the endoplasmic reticulum (ER), mediates trafficking to the Golgi. While metazoans have few genes encoding each COPII component, plants have expanded these gene families, leading to the hypothesis that plant COPII has functionally diversified. In the moss Physcomitrium (Physcomitrella) patens, the Sec23/24 gene families are each composed of seven genes. Silencing Sec23/24 revealed isoform-specific contributions to polarized growth, with the closely related Sec23D/E and Sec24C/D essential for protonemal development. Focusing on Sec23, we discovered that Sec23D/E mediate ER-to Golgi transport and are essential for tip growth, with Sec23D localizing to presumptive ER exit sites. In contrast, Sec23A, B, C, F, and G are dispensable and do not quantitatively affect ER-to-Golgi trafficking. However, Δsec23abcfg plants exhibited reduced secretion of plasma membrane cargo. Of the four highly expressed protonemal Sec23 genes, Sec23F/G are members of a divergent Sec23 clade specifically retained in land plants. Notably, Sec23G accumulates on ER-associated foci that are significantly larger, do not overlap with, and are independent of Sec23D. While Sec23D/E form ER exit sites and function as bona fide COPII components essential for tip-growing protonemata, Sec23G and the closely related Sec23F have likely functionally diversified, forming separate and independent ER exit sites and participating in Golgi-independent trafficking pathways.
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Affiliation(s)
- Mingqin Chang
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire 03755, USA
- Plant Biology Graduate Program, University of Massachusetts Amherst, Amherst, Massachusetts 01002, USA
| | - Shu-Zon Wu
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire 03755, USA
| | - Samantha E Ryken
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire 03755, USA
| | - Jacquelyn E O’Sullivan
- Department of Biology, University of Massachusetts Amherst, Amherst, Massachusetts 01002, USA
| | - Magdalena Bezanilla
- Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire 03755, USA
- Author for correspondence:
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14
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Bravo-Plaza I, Hernández-González M, Peñalva MÁ. Comment on Dimou et al. Profile of Membrane Cargo Trafficking Proteins and Transporters Expressed under N Source Derepressing Conditions in Aspergillus nidulans. J. Fungi 2021, 7, 560. J Fungi (Basel) 2021; 7:jof7121037. [PMID: 34947019 PMCID: PMC8703528 DOI: 10.3390/jof7121037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2021] [Revised: 11/10/2021] [Accepted: 11/25/2021] [Indexed: 01/02/2023] Open
Abstract
Contrary to the opinion recently offered by Dimou et al., our previously published biochemical, subcellular and genetic data supported our contention that AN11127 corresponds to the A. nidulans gene encoding Sec12, which is the guanine nucleotide exchange factor (GEF) specific for SAR1. We add here additional bioinformatics evidence that fully disprove the otherwise negative evidence reported by Dimou et al., highlighting the dangers associated with the lax interpretation of genomic data. On the positive side, we establish guidelines for the identification of this key secretory gene in other species of Ascomycota and Basidiomycota, including species of medical and applied interest.
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Affiliation(s)
- Ignacio Bravo-Plaza
- Centro de Investigaciones Biológicas Margarita Salas, CSIC, Ramiro de Maeztu 9, 28049 Madrid, Spain;
| | | | - Miguel Á. Peñalva
- Centro de Investigaciones Biológicas Margarita Salas, CSIC, Ramiro de Maeztu 9, 28049 Madrid, Spain;
- Correspondence:
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15
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Hassan Z, Kumar ND, Reggiori F, Khan G. How Viruses Hijack and Modify the Secretory Transport Pathway. Cells 2021; 10:2535. [PMID: 34685515 PMCID: PMC8534161 DOI: 10.3390/cells10102535] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 08/28/2021] [Accepted: 09/06/2021] [Indexed: 12/23/2022] Open
Abstract
Eukaryotic cells contain dynamic membrane-bound organelles that are constantly remodeled in response to physiological and environmental cues. Key organelles are the endoplasmic reticulum, the Golgi apparatus and the plasma membrane, which are interconnected by vesicular traffic through the secretory transport route. Numerous viruses, especially enveloped viruses, use and modify compartments of the secretory pathway to promote their replication, assembly and cell egression by hijacking the host cell machinery. In some cases, the subversion mechanism has been uncovered. In this review, we summarize our current understanding of how the secretory pathway is subverted and exploited by viruses belonging to Picornaviridae, Coronaviridae, Flaviviridae,Poxviridae, Parvoviridae and Herpesviridae families.
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Affiliation(s)
- Zubaida Hassan
- Department of Medical Microbiology and Immunology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain P.O. Box 17666, United Arab Emirates;
- Department of Microbiology, School of Life Sciences, Modibbo Adama University, Yola PMB 2076, Nigeria
| | - Nilima Dinesh Kumar
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, 9713 AV Groningen, The Netherlands; (N.D.K.); (F.R.)
- Department of Medical Microbiology and Infection Prevention, University of Groningen, University Medical Center Groningen, 9713 AV Groningen, The Netherlands
| | - Fulvio Reggiori
- Department of Biomedical Sciences of Cells and Systems, University of Groningen, University Medical Center Groningen, 9713 AV Groningen, The Netherlands; (N.D.K.); (F.R.)
| | - Gulfaraz Khan
- Department of Medical Microbiology and Immunology, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain P.O. Box 17666, United Arab Emirates;
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16
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Link F, Borges AR, Jones NG, Engstler M. To the Surface and Back: Exo- and Endocytic Pathways in Trypanosoma brucei. Front Cell Dev Biol 2021; 9:720521. [PMID: 34422837 PMCID: PMC8377397 DOI: 10.3389/fcell.2021.720521] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Accepted: 07/06/2021] [Indexed: 01/10/2023] Open
Abstract
Trypanosoma brucei is one of only a few unicellular pathogens that thrives extracellularly in the vertebrate host. Consequently, the cell surface plays a critical role in both immune recognition and immune evasion. The variant surface glycoprotein (VSG) coats the entire surface of the parasite and acts as a flexible shield to protect invariant proteins against immune recognition. Antigenic variation of the VSG coat is the major virulence mechanism of trypanosomes. In addition, incessant motility of the parasite contributes to its immune evasion, as the resulting fluid flow on the cell surface drags immunocomplexes toward the flagellar pocket, where they are internalized. The flagellar pocket is the sole site of endo- and exocytosis in this organism. After internalization, VSG is rapidly recycled back to the surface, whereas host antibodies are thought to be transported to the lysosome for degradation. For this essential step to work, effective machineries for both sorting and recycling of VSGs must have evolved in trypanosomes. Our understanding of the mechanisms behind VSG recycling and VSG secretion, is by far not complete. This review provides an overview of the trypanosome secretory and endosomal pathways. Longstanding questions are pinpointed that, with the advent of novel technologies, might be answered in the near future.
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Affiliation(s)
- Fabian Link
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Alyssa R Borges
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Nicola G Jones
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg, Germany
| | - Markus Engstler
- Department of Cell and Developmental Biology, Biocenter, University of Würzburg, Würzburg, Germany
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17
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Kanwal A, Joshi PV, Mandal S, Mandal L. Ubx-Collier signaling cascade maintains blood progenitors in the posterior lobes of the Drosophila larval lymph gland. PLoS Genet 2021; 17:e1009709. [PMID: 34370733 PMCID: PMC8376192 DOI: 10.1371/journal.pgen.1009709] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 08/19/2021] [Accepted: 07/12/2021] [Indexed: 12/02/2022] Open
Abstract
Drosophila larval hematopoiesis occurs in a specialized multi-lobed organ called the lymph gland. Extensive characterization of the organ has provided mechanistic insights into events related to developmental hematopoiesis. Spanning from the thoracic to the abdominal segment of the larvae, this organ comprises a pair of primary, secondary, and tertiary lobes. Much of our understanding arises from the studies on the primary lobe, while the secondary and tertiary lobes have remained mostly unexplored. Previous studies have inferred that these lobes are composed of progenitors that differentiate during pupation; however, the mechanistic basis of this extended progenitor state remains unclear. This study shows that posterior lobe progenitors are maintained by a local signaling center defined by Ubx and Collier in the tertiary lobe. This Ubx zone in the tertiary lobe shares several markers with the niche of the primary lobe. Ubx domain regulates the homeostasis of the posterior lobe progenitors in normal development and an immune-challenged scenario. Our study establishes the lymph gland as a model to tease out how the progenitors interface with the dual niches within an organ during development and disorders.
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Affiliation(s)
- Aditya Kanwal
- Developmental Genetics Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, SAS Nagar, Punjab, India
| | - Pranav Vijay Joshi
- Developmental Genetics Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, SAS Nagar, Punjab, India
| | - Sudip Mandal
- Molecular Cell and Developmental Biology Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, SAS Nagar, Punjab, India
| | - Lolitika Mandal
- Developmental Genetics Laboratory, Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Mohali, SAS Nagar, Punjab, India
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18
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Lei Z, Wang J, Zhang L, Liu CH. Ubiquitination-Dependent Regulation of Small GTPases in Membrane Trafficking: From Cell Biology to Human Diseases. Front Cell Dev Biol 2021; 9:688352. [PMID: 34277632 PMCID: PMC8281112 DOI: 10.3389/fcell.2021.688352] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Accepted: 06/09/2021] [Indexed: 01/04/2023] Open
Abstract
Membrane trafficking is critical for cellular homeostasis, which is mainly carried out by small GTPases, a class of proteins functioning in vesicle budding, transport, tethering and fusion processes. The accurate and organized membrane trafficking relies on the proper regulation of small GTPases, which involves the conversion between GTP- and GDP-bound small GTPases mediated by guanine nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs). Emerging evidence indicates that post-translational modifications (PTMs) of small GTPases, especially ubiquitination, play an important role in the spatio-temporal regulation of small GTPases, and the dysregulation of small GTPase ubiquitination can result in multiple human diseases. In this review, we introduce small GTPases-mediated membrane trafficking pathways and the biological processes of ubiquitination-dependent regulation of small GTPases, including the regulation of small GTPase stability, activity and localization. We then discuss the dysregulation of small GTPase ubiquitination and the associated human membrane trafficking-related diseases, focusing on the neurological diseases and infections. An in-depth understanding of the molecular mechanisms by which ubiquitination regulates small GTPases can provide novel insights into the membrane trafficking process, which knowledge is valuable for the development of more effective and specific therapeutics for membrane trafficking-related human diseases.
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Affiliation(s)
- Zehui Lei
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Beijing, China.,Savaid Medical School, University of Chinese Academy of Sciences, Beijing, China
| | - Jing Wang
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Beijing, China
| | - Lingqiang Zhang
- State Key Laboratory of Proteomics, Beijing Proteome Research Center, National Center for Protein Sciences (Beijing), Beijing Institute of Lifeomics, Beijing, China
| | - Cui Hua Liu
- CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Center for Biosafety Mega-Science, Chinese Academy of Sciences, Beijing, China.,Savaid Medical School, University of Chinese Academy of Sciences, Beijing, China
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19
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Dautt-Castro M, Rosendo-Vargas M, Casas-Flores S. The Small GTPases in Fungal Signaling Conservation and Function. Cells 2021; 10:cells10051039. [PMID: 33924947 PMCID: PMC8146680 DOI: 10.3390/cells10051039] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 04/22/2021] [Accepted: 04/23/2021] [Indexed: 12/28/2022] Open
Abstract
Monomeric GTPases, which belong to the Ras superfamily, are small proteins involved in many biological processes. They are fine-tuned regulated by guanine nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs). Several families have been identified in organisms from different kingdoms. Overall, the most studied families are Ras, Rho, Rab, Ran, Arf, and Miro. Recently, a new family named Big Ras GTPases was reported. As a general rule, the proteins of all families have five characteristic motifs (G1–G5), and some specific features for each family have been described. Here, we present an exhaustive analysis of these small GTPase families in fungi, using 56 different genomes belonging to different phyla. For this purpose, we used distinct approaches such as phylogenetics and sequences analysis. The main functions described for monomeric GTPases in fungi include morphogenesis, secondary metabolism, vesicle trafficking, and virulence, which are discussed here. Their participation during fungus–plant interactions is reviewed as well.
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20
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Enkler L, Rinaldi B, de Craene JO, Hammann P, Nureki O, Senger B, Friant S, Becker HD. Cex1 is a component of the COPI intracellular trafficking machinery. Biol Open 2021; 10:bio.058528. [PMID: 33753324 PMCID: PMC8015235 DOI: 10.1242/bio.058528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
COPI (coatomer complex I) coated vesicles are involved in Golgi-to-ER and intra-Golgi trafficking pathways, and mediate retrieval of ER resident proteins. Functions and components of the COPI-mediated trafficking pathways, beyond the canonical set of Sec/Arf proteins, are constantly increasing in number and complexity. In mammalian cells, GORAB, SCYL1 and SCYL3 proteins regulate Golgi morphology and protein glycosylation in concert with the COPI machinery. Here, we show that Cex1, homologous to the mammalian SCYL proteins, is a component of the yeast COPI machinery, by interacting with Sec27, Sec28 and Sec33 (Ret1/Cop1) proteins of the COPI coat. Cex1 was initially reported to mediate channeling of aminoacylated tRNA outside of the nucleus. Our data show that Cex1 localizes at membrane compartments, on structures positive for the Sec33 α-COP subunit. Moreover, the Wbp1 protein required for N-glycosylation and interacting via its di-lysine motif with the Sec27 β′-COP subunit is mis-targeted in cex1Δ deletion mutant cells. Our data point to the possibility of developing Cex1 yeast-based models to study neurodegenerative disorders linked to pathogenic mutations of its human homologue SCYL1. Summary: Cex1, the yeast homologue of mammalian SCYL1, interacts with COPI coat components and is recruited to the Golgi to regulate retrograde vesicular trafficking and sorting
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Affiliation(s)
- Ludovic Enkler
- Génétique Moléculaire et Cellulaire, Université de Strasbourg, CNRS, GMGM UMR7156, F-67000 Strasbourg, France
| | - Bruno Rinaldi
- Génétique Moléculaire et Cellulaire, Université de Strasbourg, CNRS, GMGM UMR7156, F-67000 Strasbourg, France
| | - Johan Owen de Craene
- Génétique Moléculaire et Cellulaire, Université de Strasbourg, CNRS, GMGM UMR7156, F-67000 Strasbourg, France
| | - Philippe Hammann
- 'Architecture et Réactivité de l'ARN', Université de Strasbourg, CNRS, Institut de Biologie Moléculaire et Cellulaire, F-67000 Strasbourg, France
| | - Osamu Nureki
- Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, Tokyo 113-0032, Japan
| | - Bruno Senger
- Génétique Moléculaire et Cellulaire, Université de Strasbourg, CNRS, GMGM UMR7156, F-67000 Strasbourg, France
| | - Sylvie Friant
- Génétique Moléculaire et Cellulaire, Université de Strasbourg, CNRS, GMGM UMR7156, F-67000 Strasbourg, France
| | - Hubert D Becker
- Génétique Moléculaire et Cellulaire, Université de Strasbourg, CNRS, GMGM UMR7156, F-67000 Strasbourg, France
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21
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Taku I, Hirai T, Makiuchi T, Shinzawa N, Iwanaga S, Annoura T, Nagamune K, Nozaki T, Saito-Nakano Y. Rab5b-Associated Arf1 GTPase Regulates Export of N-Myristoylated Adenylate Kinase 2 From the Endoplasmic Reticulum in Plasmodium falciparum. Front Cell Infect Microbiol 2021; 10:610200. [PMID: 33604307 PMCID: PMC7884776 DOI: 10.3389/fcimb.2020.610200] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Accepted: 12/17/2020] [Indexed: 01/08/2023] Open
Abstract
Plasmodium falciparum extensively remodels human erythrocytes by exporting hundreds of parasite proteins. This remodeling is closely linked to the Plasmodium virulence-related functions and immune evasion. The N-terminal export signal named PEXEL (Plasmodium export element) was identified to be important for the export of proteins beyond the PVM, however, the issue of how these PEXEL-positive proteins are transported and regulated by Rab GTPases from the endoplasmic reticulum (ER) to the cell surface has remained poorly understood. Previously, we identified new aspects of the trafficking of N-myristoylated adenylate kinase 2 (PfAK2), which lacks the PEXEL motif and is regulated by the PfRab5b GTPase. Overexpression of PfRab5b suppressed the transport of PfAK2 to the parasitophorous vacuole membrane and PfAK2 was accumulated in the punctate compartment within the parasite. Here, we report the identification of PfRab5b associated proteins and dissect the pathway regulated by PfRab5b. We isolated two membrane trafficking GTPases PfArf1 and PfRab1b by coimmunoprecipitation with PfRab5b and via mass analysis. PfArf1 and PfRab1b are both colocalized with PfRab5b adjacent to the ER in the early erythrocytic stage. A super-resolution microgram of the indirect immunofluorescence assay using PfArf1 or PfRab1b- expressing parasites revealed that PfArf1 and PfRab1b are localized to different ER subdomains. We used a genetic approach to expresses an active or inactive mutant of PfArf1 that specifically inhibited the trafficking of PfAK2 to the parasitophorous vacuole membrane. While expression of PfRab1b mutants did not affect in the PfAK2 transport. In contrast, the export of the PEXEL-positive protein Rifin was decreased by the expression of the inactive mutant of PfRab1b or PfArf1. These data indicate that the transport of PfAK2 and Rifin were recognized at the different ER subdomain by the two independent GTPases: PfAK2 is sorted by PfArf1 into the pathway for the PV, and the export of Rifin might be sequentially regulated by PfArf1 and PfRab1b.
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Affiliation(s)
- Izumi Taku
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan.,Graduate School of Life and Environmental Sciences, University of Tsukuba, Ibaraki, Japan
| | - Tomohiro Hirai
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan.,Graduate School of Life and Environmental Sciences, University of Tsukuba, Ibaraki, Japan
| | - Takashi Makiuchi
- Department of Parasitology, Tokai University School of Medicine, Isehara, Japan
| | - Naoaki Shinzawa
- Department of Environmental Parasitology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Shiroh Iwanaga
- Department of Environmental Parasitology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Takeshi Annoura
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Kisaburo Nagamune
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan.,Faculty of Life and Environmental Sciences, University of Tsukuba, Ibaraki, Japan
| | - Tomoyoshi Nozaki
- Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Yumiko Saito-Nakano
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan
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22
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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.
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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
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23
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Ko DK, Brandizzi F. A temporal hierarchy underpins the transcription factor-DNA interactome of the maize UPR. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2021; 105:254-270. [PMID: 33098715 PMCID: PMC7942231 DOI: 10.1111/tpj.15044] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Revised: 09/18/2020] [Accepted: 09/23/2020] [Indexed: 05/10/2023]
Abstract
Adverse environmental conditions reduce crop productivity and often increase the load of unfolded or misfolded proteins in the endoplasmic reticulum (ER). This potentially lethal condition, known as ER stress, is buffered by the unfolded protein response (UPR), a set of signaling pathways designed to either recover ER functionality or ignite programmed cell death. Despite the biological significance of the UPR to the life of the organism, the regulatory transcriptional landscape underpinning ER stress management is largely unmapped, especially in crops. To fill this significant knowledge gap, we performed a large-scale systems-level analysis of the protein-DNA interaction (PDI) network in maize (Zea mays). Using 23 promoter fragments of six UPR marker genes in a high-throughput enhanced yeast one-hybrid assay, we identified a highly interconnected network of 262 transcription factors (TFs) associated with significant biological traits and 831 PDIs underlying the UPR. We established a temporal hierarchy of TF binding to gene promoters within the same family as well as across different families of TFs. Cistrome analysis revealed the dynamic activities of a variety of cis-regulatory elements (CREs) in ER stress-responsive gene promoters. By integrating the cistrome results into a TF network analysis, we mapped a subnetwork of TFs associated with a CRE that may contribute to UPR management. Finally, we validated the role of a predicted network hub gene using the Arabidopsis system. The PDIs, TF networks, and CREs identified in our work are foundational resources for understanding transcription-regulatory mechanisms in the stress responses and crop improvement.
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Affiliation(s)
- Dae Kwan Ko
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, Michigan, 48824
- Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, Michigan, 48824
| | - Federica Brandizzi
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, Michigan, 48824
- Department of Plant Biology, Michigan State University, East Lansing, Michigan, 48824
- Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, Michigan, 48824
- Correspondence:
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24
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Abstract
In 1994, a convergence of ideas and collaborative research orchestrated by Randy Schekman led to the discovery of the coat protein complex II (COPII). In this Perspective, the chain of events enabling discovery of a new vesicle coat and progress on understanding COPII budding mechanisms are considered.
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Affiliation(s)
- Charles Barlowe
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755
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25
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Osmani Z, Sabet MS, Nakahara KS, Mokhtassi-Bidgoli A, Vahabi K, Moieni A, Shams-Bakhsh M. Identification of a defense response gene involved in signaling pathways against PVA and PVY in potato. GM CROPS & FOOD 2020; 12:86-105. [PMID: 33028148 PMCID: PMC7553743 DOI: 10.1080/21645698.2020.1823776] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Potato is the most important non-grain food crop in the world. Viruses, particularly potato virus Y (PVY) and potato virus A (PVA), are among the major agricultural pathogens causing severe reduction in potato yield and quality worldwide. Virus infection induces host factors to interfere with its infection cycle. Evaluation of these factors facilitates the development of intrinsic resistance to plant viruses. In this study, a small G-protein as one of the critical signaling factors was evaluated in plant response to PVY and PVA to enhance resistance. For this purpose, the gene expression dataset of G-proteins in potato plant under five biotic (viruses, bacteria, fungi, nematodes, and insects) and four abiotic (cold, heat, salinity, and drought) stress conditions were collected from gene expression databases. We reduced the number of the selected G-proteins to a single protein, StSAR1A, which is possibly involved in virus inhibition. StSAR1A overexpressed transgenic plants were created via the Agrobacterium-mediated method. Real-time PCR and Enzyme-linked immunosorbent assay tests of transgenic plants mechanically inoculated with PVY and PVA indicated that the overexpression of StSAR1A gene enhanced resistance to both viruses. The virus-infected transgenic plants exhibited a greater stem length, a larger leaf size, a higher fresh/dry weight, and a greater node number than those of the wild-type plants. The maximal photochemical efficiency of photosystem II, stomatal conductivity, and net photosynthetic rate in the virus-infected transgenic plants were also obviously higher than those of the control. The present study may help to understand aspects of resistance against viruses.
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Affiliation(s)
- Zhila Osmani
- Department of Plant Genetics and Breeding, Faculty of Agriculture, Tarbiat Modares University , Tehran, Iran
| | - Mohammad Sadegh Sabet
- Department of Plant Genetics and Breeding, Faculty of Agriculture, Tarbiat Modares University , Tehran, Iran
| | - Kenji S Nakahara
- Research Faculty of Agriculture, Hokkaido University , Sapporo Japan
| | - Ali Mokhtassi-Bidgoli
- Department of Agronomy, Faculty of Agriculture, Tarbiat Modares University , Tehran, Iran
| | - Khabat Vahabi
- Department of Cell and Metabolic Biology, Leibniz Institute of Plant Biochemistry, Friedrich-Schiller- University , Jena, Germany
| | - Ahmad Moieni
- Department of Plant Genetics and Breeding, Faculty of Agriculture, Tarbiat Modares University , Tehran, Iran
| | - Masoud Shams-Bakhsh
- Department of Plant Pathology, Faculty of Agriculture, Tarbiat Modares University , Tehran, Iran
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Murakami-Sekimata A, Sekimata M, Sato N, Hayasaka Y, Nakano A. Deletion of PIN4 Suppresses the Protein Transport Defects Caused by sec12-4 Mutation in Saccharomyces cerevisiae. Microb Physiol 2020; 30:25-35. [PMID: 32958726 DOI: 10.1159/000509633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 06/24/2020] [Indexed: 11/19/2022]
Abstract
Newly synthesized secretory proteins are released into the lumen of the endoplasmic reticulum (ER). The secretory proteins are surrounded by coat protein complex II (COPII) vesicles, and transported from the ER and reach their destinations through the Golgi apparatus. Sec12p is a guanine nucleotide exchange factor for Sar1p, which initiates COPII vesicle budding from the ER. The activation of Sar1p by Sec12p and the subsequent COPII coat assembly have been well characterized, but the events that take place upstream of Sec12p remain unclear. In this study, we isolated the novel extragenic suppressor of sec12-4, PIN4/MDT1, a cell cycle checkpoint target. A yeast two-hybrid screening was used to identify Pin4/Mdt1p as a binding partner of the casein kinase I isoform Hrr25p, which we have previously identified as a modulator of Sec12p function. Deletion of PIN4 suppressed both defects of temperature-sensitive growth and the partial protein transport observed in sec12-4 mutants. The results of this study suggest that Pin4p provides novel aspects of Sec12p modulations.
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Affiliation(s)
- Akiko Murakami-Sekimata
- Division of Theoretical Nursing and Genetics, Graduate School of Medical Science, Yamagata University Faculty of Medicine, Yamagata, Japan,
| | - Masayuki Sekimata
- Radioisotope Research Center, School of Medicine, Fukushima Medical University, Fukushima, Japan
| | - Natsumi Sato
- Division of Theoretical Nursing and Genetics, Graduate School of Medical Science, Yamagata University Faculty of Medicine, Yamagata, Japan
| | - Yuto Hayasaka
- Division of Theoretical Nursing and Genetics, Graduate School of Medical Science, Yamagata University Faculty of Medicine, Yamagata, Japan
| | - Akihiko Nakano
- Live Cell Super-Resolution Imaging Research Team, Extreme Photonics Research Group, RIKEN Center for Advanced Photonics, Wako, Japan
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27
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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.
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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
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28
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Takagi J, Kimori Y, Shimada T, Hara-Nishimura I. Dynamic Capture and Release of Endoplasmic Reticulum Exit Sites by Golgi Stacks in Arabidopsis. iScience 2020; 23:101265. [PMID: 32585594 PMCID: PMC7322076 DOI: 10.1016/j.isci.2020.101265] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 05/09/2020] [Accepted: 06/08/2020] [Indexed: 12/21/2022] Open
Abstract
Protein transport from the endoplasmic reticulum (ER) to Golgi stacks is mediated by the coat protein complex COPII, which is assembled at an ER subdomain called ER exit site (ERES). However, the dynamic relationship between ERESs and Golgi stacks is unknown. Here, we propose a dynamic capture-and-release model of ERESs by Golgi stacks in Arabidopsis thaliana. Using variable-angle epifluorescence microscopy with high-temporal-resolution imaging, COPII-component-bound ERESs were detected as punctate structures with sizes of 300–500 nm. Some punctate ERESs are distributed on ER tubules and sheet rims, whereas others gather around a Golgi stack in an ER-network cavity to form a beaded-ring structure. Free ERESs that wander into an ER cavity are captured by a Golgi stack in a cytoskeleton-independent manner. Then, they are released by the Golgi stack for recycling. The dynamic ERES cycling might contribute to efficient transfer of de novo synthesized cargo proteins from the ER to Golgi stacks. VAEM images show dynamic behavior of minimal punctate ERESs Most of punctate ERESs are distributed on the ER network tubes Several punctate ERESs contact with a Golgi stack in an ER network cavity ERESs are dynamically captured and released by Golgi stacks
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Affiliation(s)
- Junpei Takagi
- Faculty of Science and Engineering, Konan University, Kobe 658-8501, Japan
| | - Yoshitaka Kimori
- Faculty of Environmental and Information Sciences, Fukui University of Technology, Fukui 910-8505, Japan
| | - Tomoo Shimada
- Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan
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29
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Lu CL, Kim J. Consequences of mutations in the genes of the ER export machinery COPII in vertebrates. Cell Stress Chaperones 2020; 25:199-209. [PMID: 31970693 PMCID: PMC7058761 DOI: 10.1007/s12192-019-01062-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 11/14/2019] [Accepted: 12/13/2019] [Indexed: 11/28/2022] Open
Abstract
Coat protein complex II (COPII) plays an essential role in the export of cargo molecules such as secretory proteins, membrane proteins, and lipids from the endoplasmic reticulum (ER). In yeast, the COPII machinery is critical for cell viability as most COPII knockout mutants fail to survive. In mice and fish, homozygous knockout mutants of most COPII genes are embryonic lethal, reflecting the essentiality of the COPII machinery in the early stages of vertebrate development. In humans, COPII mutations, which are often hypomorphic, cause diseases having distinct clinical features. This is interesting as the fundamental cellular defect of these diseases, that is, failure of ER export, is similar. Analyses of humans and animals carrying COPII mutations have revealed clues to why a similar ER export defect can cause such different diseases. Previous reviews have focused mainly on the deficit of secretory or membrane proteins in the final destinations because of an ER export block. In this review, we also underscore the other consequence of the ER export block, namely ER stress triggered by the accumulation of cargo proteins in the ER.
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Affiliation(s)
- Chung-Ling Lu
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, 1800 Christensen Drive, Ames, IA, 50011, USA
| | - Jinoh Kim
- Department of Biomedical Sciences, College of Veterinary Medicine, Iowa State University, 1800 Christensen Drive, Ames, IA, 50011, USA.
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Bowazolo C, Tse SPK, Beauchemin M, Lo SCL, Rivoal J, Morse D. Label-free MS/MS analyses of the dinoflagellate Lingulodinium identifies rhythmic proteins facilitating adaptation to a diurnal LD cycle. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 704:135430. [PMID: 31818571 DOI: 10.1016/j.scitotenv.2019.135430] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 11/01/2019] [Accepted: 11/06/2019] [Indexed: 06/10/2023]
Abstract
Protein levels were assessed in the dinoflagellate Lingulodinium polyedra over the course of a diurnal cycle using a label-free LC-MS/MS approach. Roughly 1700 proteins were quantitated in a triplicate dataset over a daily period, and 13 were found to show significant rhythmic changes. Included among the proteins found to be most abundant at night were the two bioluminescence proteins, luciferase and luciferin binding protein, as well as a proliferating cell nuclear protein involved in the nightly DNA replication. Aconitase and a pyrophosphate fructose-6-phosphate-1-phosphotransferase were also found to be more abundant at night, suggestive of an increased ability to generate ATP by glucose catabolism when photosynthesis does not occur. Among the proteins more abundant during the day were found a 2-epi-5-epi-valiolone synthase, potentially involved in synthesis of mycosporin-like amino acids that can act as a "microbial sunscreen", and an enzyme synthesizing vitamin B6 which is known to protect against oxidative stress. A lactate oxidoreductase was also found to be more abundant during the day, perhaps to counteract the pH changes due to carbon fixation by facilitating conversion of pyruvate to lactate. This unbiased proteomic approach reveals novel insights into the daily metabolic changes of this dinoflagellate. Furthermore, the observation that only a limited number of proteins vary support a model where metabolic flux through pathways can be controlled by variations in a select few, possibly rate limiting, steps. Data are available via ProteomeXchange with identifier PXD006994.
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Affiliation(s)
- Carl Bowazolo
- Institut de Recherche en biologie Végétale, Département de Sciences Biologiques, Université de Montréal, Canada
| | - Sirius P K Tse
- Shenzhen Key Laboratory of Food Biological Safety Control, Department of Applied Biology and Chemical Technology, Hung Hom, Kowloon, Hong Kong SAR, China
| | - Mathieu Beauchemin
- Institut de Recherche en biologie Végétale, Département de Sciences Biologiques, Université de Montréal, Canada
| | - Samuel C-L Lo
- Shenzhen Key Laboratory of Food Biological Safety Control, Department of Applied Biology and Chemical Technology, Hung Hom, Kowloon, Hong Kong SAR, China
| | - Jean Rivoal
- Institut de Recherche en biologie Végétale, Département de Sciences Biologiques, Université de Montréal, Canada
| | - David Morse
- Institut de Recherche en biologie Végétale, Département de Sciences Biologiques, Université de Montréal, Canada
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31
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Yorimitsu T, Sato K. Sec16 function in ER export and autophagy is independent of its phosphorylation in Saccharomyces cerevisiae. Mol Biol Cell 2019; 31:149-156. [PMID: 31851588 PMCID: PMC7001475 DOI: 10.1091/mbc.e19-08-0477] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Coat protein complex II (COPII) protein assembles at the endoplasmic reticulum exit site (ERES) to form vesicle carrier for transport from the ER to the Golgi apparatus. Sec16 has a critical role in COPII assembly to form ERES. Sec16∆565N mutant, which lacks the N-terminal 565 amino acids, is defective in ERES formation and ER export. Several phosphoproteomic studies have identified 108 phosphorylated Ser/Thr/Tyr residues in Sec16 of Saccharomyces cerevisiae, of which 30 residues are located in the truncated part of Sec16∆565N. The exact role of the phosphorylation in Sec16 function remains to be determined. Therefore, we analyzed nonphosphorylatable Sec16 mutants, in which all identified phosphorylation sites are substituted with Ala. These mutants show ERES and ER export comparable to those of wild-type Sec16, although the nonphosphorylatable mutant binds the COPII subunit Sec23 more efficiently than the wild-type protein. Because nutrient starvation–induced autophagy depends on Sec16, Sec16∆565N impairs autophagy, whereas the nonphosphorylatable mutants do not affect autophagy. We conclude that Sec16 phosphorylation is not essential for its function.
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Affiliation(s)
- Tomohiro Yorimitsu
- Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Tokyo 153-8902, Japan
| | - Ken Sato
- Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Tokyo 153-8902, Japan
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32
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ER-to-Golgi Transport: A Sizeable Problem. Trends Cell Biol 2019; 29:940-953. [DOI: 10.1016/j.tcb.2019.08.007] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 08/22/2019] [Accepted: 08/23/2019] [Indexed: 11/16/2022]
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Zhang S, Yang L, Li L, Zhong K, Wang W, Liu M, Li Y, Liu X, Yu R, He J, Zhang H, Zheng X, Wang P, Zhang Z. System-Wide Characterization of MoArf GTPase Family Proteins and Adaptor Protein MoGga1 Involved in the Development and Pathogenicity of Magnaporthe oryzae. mBio 2019; 10:e02398-19. [PMID: 31615964 PMCID: PMC6794486 DOI: 10.1128/mbio.02398-19] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Accepted: 09/17/2019] [Indexed: 12/18/2022] Open
Abstract
ADP ribosylation factor (Arf) small GTPase family members are involved in vesicle trafficking and organelle maintenance in organisms ranging from Saccharomyces cerevisiae to humans. A previous study identified Magnaporthe oryzae Arf6 (MoArf6) as one of the Arf proteins that regulates growth and conidiation in the rice blast fungus M. oryzae, but the remaining family proteins remain unknown. Here, we identified six additional Arf proteins, including MoArf1, MoArl1, MoArl3, MoArl8, MoCin4, and MoSar1, as well as their sole adaptor protein, MoGga1, and determined their shared and specific functions. We showed that the majority of these proteins exhibit positive regulatory functions, most notably, in growth. Importantly, MoArl1, MoCin4, and MoGga1 are involved in pathogenicity through the regulation of host penetration and invasive hyphal growth. MoArl1 and MoCin4 also regulate normal vesicle trafficking, and MoCin4 further controls the formation of the biotrophic interfacial complex (BIC). Moreover, we showed that Golgi-cytoplasm cycling of MoArl1 is required for its function. Finally, we demonstrated that interactions between MoArf1 and MoArl1 with MoGga1 are important for Golgi localization and pathogenicity. Collectively, our findings revealed the shared and specific functions of Arf family members in M. oryzae and shed light on how these proteins function through conserved mechanisms to govern growth, transport, and virulence of the blast fungus.IMPORTANCEMagnaporthe oryzae is the causal agent of rice blast, representing the most devastating diseases of rice worldwide, which results in losses of amounts of rice that could feed more than 60 million people each year. Arf (ADP ribosylation factor) small GTPase family proteins are involved in vesicle trafficking and organelle maintenance in eukaryotic cells. To investigate the function of Arf family proteins in M. oryzae, we systematically characterized all seven Arf proteins and found that they have shared and specific functions in governing the growth, development, and pathogenicity of the blast fungus. We have also identified the pathogenicity-related protein MoGga1 as the common adaptor of MoArf1 and MoArl1. Our findings are important because they provide the first comprehensive characterization of the Arf GTPase family proteins and their adaptor protein MoGga1 functioning in a plant-pathogenic fungus, which could help to reveal new fungicide targets to control this devastating disease.
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Affiliation(s)
- Shengpei Zhang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Lina Yang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Lianwei Li
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Kaili Zhong
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Wenhao Wang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Muxing Liu
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Ying Li
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Xinyu Liu
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Rui Yu
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Jialiang He
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Haifeng Zhang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Xiaobo Zheng
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
| | - Ping Wang
- Department of Pediatrics, Louisiana State University Health Sciences Center, New Orleans, Louisiana, USA
- Department of Microbiology, Immunology & Parasitology, Louisiana State University Health Sciences Center, New Orleans, Louisiana, USA
| | - Zhengguang Zhang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, Nanjing, China
- Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing, China
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Abstract
Formation of a transport vesicle in membrane trafficking pathways requires deformation of the membrane to form a highly curved structure. A recent study reveals a crucial function for the conical lipid lysophosphatidylinositol in reducing the bending rigidity of the membrane during COPII vesicle budding in the early secretory pathway.
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35
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Identification of the guanine nucleotide exchange factor for SAR1 in the filamentous fungal model Aspergillus nidulans. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2019; 1866:118551. [PMID: 31487505 DOI: 10.1016/j.bbamcr.2019.118551] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 08/02/2019] [Accepted: 08/11/2019] [Indexed: 12/30/2022]
Abstract
In spite of its basic and applied interest, the regulation of ER exit by filamentous fungi is insufficiently understood. In previous work we isolated a panel of conditional mutations in sarA encoding the master GTPase SarASAR1 in A. nidulans and demonstrated its key role in exocytosis and hyphal morphogenesis. However, the SAR1 guanine nucleotide exchange factor (GEF), Sec12, has not been characterized in any filamentous fungus, largely due to the fact that SEC12 homologues share little amino acid sequence identity beyond a GGGGxxxxGϕxN motif involved in guanine nucleotide exchange. Here we demonstrate that AN11127 encodes A. nidulans Sec12, which is an essential protein that localizes to the ER and that, when overexpressed, rescues the growth defect resulting from a hypomorphic sarA6ts mutation at 37 °C. Using purified, bacterially expressed proteins we demonstrate that the product of AN11127 accelerates nucleotide exchange on SarASAR1, but not on its closely related GTPase ArfAARF1, as expected for a bona fide GEF. The unequivocal characterization of A. nidulans Sec12 paves the way for the tailored modification of ER exit in a model organism that is closely related to industrial species of filamentous fungi.
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36
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Peotter J, Kasberg W, Pustova I, Audhya A. COPII-mediated trafficking at the ER/ERGIC interface. Traffic 2019; 20:491-503. [PMID: 31059169 PMCID: PMC6640837 DOI: 10.1111/tra.12654] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 04/25/2019] [Accepted: 05/02/2019] [Indexed: 12/16/2022]
Abstract
Coat proteins play multiple roles in the life cycle of a membrane-bound transport intermediate, functioning in lipid bilayer remodeling, cargo selection and targeting to an acceptor compartment. The Coat Protein complex II (COPII) coat is known to act in each of these capacities, but recent work highlights the necessity for numerous accessory factors at all stages of transport carrier existence. Here, we review recent findings that highlight the roles of COPII and its regulators in the biogenesis of tubular COPII-coated carriers in mammalian cells that enable cargo transport between the endoplasmic reticulum and ER-Golgi intermediate compartments, the first step in a series of trafficking events that ultimately allows for the distribution of biosynthetic secretory cargoes throughout the entire endomembrane system.
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Affiliation(s)
- Jennifer Peotter
- Department of Biomolecular Chemistry, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin
| | - William Kasberg
- Department of Biomolecular Chemistry, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin
| | - Iryna Pustova
- Department of Biomolecular Chemistry, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin
| | - Anjon Audhya
- Department of Biomolecular Chemistry, University of Wisconsin-Madison School of Medicine and Public Health, Madison, Wisconsin
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37
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Jepson JEC, Praschberger R, Krishnakumar SS. Mechanisms of Neurological Dysfunction in GOSR2 Progressive Myoclonus Epilepsy, a Golgi SNAREopathy. Neuroscience 2019; 420:41-49. [PMID: 30954670 DOI: 10.1016/j.neuroscience.2019.03.057] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 03/22/2019] [Accepted: 03/26/2019] [Indexed: 10/27/2022]
Abstract
Successive fusion events between transport vesicles and their target membranes mediate trafficking of secreted, membrane- and organelle-localised proteins. During the initial steps of this process, termed the secretory pathway, COPII vesicles bud from the endoplasmic reticulum (ER) and fuse with the cis-Golgi membrane, thus depositing their cargo. This fusion step is driven by a quartet of SNARE proteins that includes the cis-Golgi t-SNARE Membrin, encoded by the GOSR2 gene. Mis-sense mutations in GOSR2 result in Progressive Myoclonus Epilepsy (PME), a severe neurological disorder characterised by ataxia, myoclonus and seizures in the absence of significant cognitive impairment. However, given the ubiquitous and essential function of ER-to-Golgi transport, why GOSR2 mutations cause neurological dysfunction and not lethality or a broader range of developmental defects has remained an enigma. Here we highlight new work that has shed light on this issue and incorporate insights into canonical and non-canonical secretory trafficking pathways in neurons to speculate as to the cellular and molecular mechanisms underlying GOSR2 PME. This article is part of a Special Issue entitled: SNARE proteins: a long journey of science in brain physiology and pathology: from molecular.
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Affiliation(s)
- James E C Jepson
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, UK.
| | - Roman Praschberger
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, UK
| | - Shyam S Krishnakumar
- Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, London, UK; Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA
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38
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Sun X, Su X. Harnessing the knowledge of protein secretion for enhanced protein production in filamentous fungi. World J Microbiol Biotechnol 2019; 35:54. [PMID: 30900052 DOI: 10.1007/s11274-019-2630-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 03/08/2019] [Indexed: 12/19/2022]
Abstract
Filamentous fungi are important microorganisms used in industrial production of proteins and enzymes. Among these organisms, Trichoderma reesei, Aspergilli, and more recently Myceliophthora thermophile are the most widely used and promising ones which have powerful protein secretion capability. In recent years, there have been tremendous achievements in understanding the molecular mechanisms of the secretory pathways in filamentous fungi. The acquired pieces of knowledge can be harnessed to enhance protein production in filamentous fungi with assistance of state-of-the-art genetic engineering techniques.
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Affiliation(s)
- Xianhua Sun
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 South Zhongguancun Street, Beijing, 100081, China
| | - Xiaoyun Su
- Key Laboratory for Feed Biotechnology of the Ministry of Agriculture, Feed Research Institute, Chinese Academy of Agricultural Sciences, No. 12 South Zhongguancun Street, Beijing, 100081, China.
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Kurokawa K, Nakano A. The ER exit sites are specialized ER zones for the transport of cargo proteins from the ER to the Golgi apparatus. J Biochem 2019; 165:109-114. [PMID: 30304445 DOI: 10.1093/jb/mvy080] [Citation(s) in RCA: 41] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2018] [Accepted: 10/05/2018] [Indexed: 12/29/2022] Open
Abstract
The endoplasmic reticulum (ER) is a multifunctional organelle, including secretory protein biogenesis, lipid synthesis, drug metabolism, Ca2+ signalling and so on. Since the ER is a single continuous membrane structure, it includes distinct zones responsible for its different functions. The export of newly synthesized proteins from the ER is facilitated via coat protein complex II (COPII)-coated vesicles, which form in specialized zones within the ER, called the ER exit sites (ERES) or transitional ER. In this review, we highlight recent advances in our understanding of the structural organization of ERES, the correlation between the ERES and Golgi organization, and the faithful cargo transport mechanism from the ERES to the Golgi.
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Affiliation(s)
- Kazuo Kurokawa
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
| | - Akihiko Nakano
- Live Cell Super-Resolution Imaging Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
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40
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Paraan M, Bhattacharya N, Uversky VN, Stagg SM. Flexibility of the Sec13/31 cage is influenced by the Sec31 C-terminal disordered domain. J Struct Biol 2018; 204:250-260. [PMID: 30172710 PMCID: PMC6188663 DOI: 10.1016/j.jsb.2018.08.016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 08/23/2018] [Accepted: 08/29/2018] [Indexed: 01/30/2023]
Abstract
In COPII mediated vesicle formation, Sec13/Sec31 heterotetramers play a role in organizing the membranes into a spherical vesicle. There they oligomerize into a cage that interacts with the other COPII proteins to direct vesicle formation and concentrate cargo into a bud. In this role they must be flexible to accommodate different sizes and shapes of cargo, but also have elements that provide rigidity to help deform the membrane. Here we characterize the influence the C-terminal disordered region of Sec31 has on cage flexibility and rigidity. After deleting this region (residues 820-1220), we characterized Sec13/Sec31ΔC heterotetramers biophysically and structurally through cryo-EM. Our results show that Sec13/31ΔC self-assembles into canonical cuboctahedral cages in vitro at buffer conditions similar to wild type. The distribution of cage sizes indicated that unlike the wild type, Sec13/31ΔC cages have a more homogeneous geometry. However, the structure of cuboctahedrons exhibited more conformational heterogeneity than wild type. Through localized reconstruction of cage vertices and molecular dynamics flexible fitting we found a new hinge for the flexing of Sec31 β-propeller domain and more flexibility of the previously known hinge. Together, these results show that the C-terminal region of Sec31 regulates the flexing of other domains such that flexibility and rigidity are not compromised during transport of large and/or asymmetric cargo.
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Affiliation(s)
- Mohammadreza Paraan
- Institute of Molecular Biophysics, 91 Chieftan Way, Florida State University, Tallahassee, FL 32306, USA
| | - Nilakshee Bhattacharya
- Institute of Molecular Biophysics, 91 Chieftan Way, Florida State University, Tallahassee, FL 32306, USA
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA; Institute for Biological Instrumentation of the Russian Academy of Sciences, Pushchino, Moscow Region 142290, Russia
| | - Scott M Stagg
- Institute of Molecular Biophysics, 91 Chieftan Way, Florida State University, Tallahassee, FL 32306, USA; Department of Chemistry and Biochemistry, 95 Chieftain Way, Florida State University, Tallahassee, FL 32306, USA.
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41
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Celińska E, Nicaud JM. Filamentous fungi-like secretory pathway strayed in a yeast system: peculiarities of Yarrowia lipolytica secretory pathway underlying its extraordinary performance. Appl Microbiol Biotechnol 2018; 103:39-52. [PMID: 30353423 PMCID: PMC6311201 DOI: 10.1007/s00253-018-9450-2] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 10/09/2018] [Accepted: 10/10/2018] [Indexed: 12/22/2022]
Abstract
Microbial production of secretory proteins constitutes one of the key branches of current industrial biotechnology, earning billion dollar (USD) revenues each year. That industrial branch strongly relies on fluent operation of the secretory machinery within a microbial cell. The secretory machinery, directing the nascent polypeptide to its final destination, constitutes a highly complex system located across the eukaryotic cell. Numerous molecular identities of diverse structure and function not only build the advanced network assisting folding, maturation and secretion of polypeptides but also serve as sensors and effectors of quality control points. All these events must be harmoniously orchestrated to enable fluent processing of the protein traffic. Availability of these elements is considered to be the limiting factor determining capacity of protein traffic, which is of crucial importance upon biotechnological production of secretory proteins. The main purpose of this work is to review and discuss findings concerning secretory machinery operating in a non-conventional yeast species, Yarrowia lipolytica, and to highlight peculiarities of this system prompting its use as the production host. The reviewed literature supports the thesis that secretory machinery in Y. lipolytica is characterized by significantly higher complexity than a canonical yeast protein secretion pathway, making it more similar to filamentous fungi-like systems in this regard.
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Affiliation(s)
- Ewelina Celińska
- Department of Biotechnology and Food Microbiology, Poznan University of Life Sciences, ul. Wojska Polskiego 48, 60-627, Poznań, Poland.
| | - Jean-Marc Nicaud
- INRA-AgroParisTech, UMR1319, Team BIMLip: Integrative Metabolism of Microbial Lipids, Micalis Institute, Domaine de Vilvert, 78352, Jouy-en-Josas, France
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42
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Zhang F, Wang Y, Wang T, Yao L, Lam SM, Huang X, Fan J, Wang Q, Liu L, Jiang Y, Zhang H, Shi L, Yu M, Shui G, Wang Y, Gao F, Zhang X, Xu Z. cTAGE5/MEA6 plays a critical role in neuronal cellular components trafficking and brain development. Proc Natl Acad Sci U S A 2018; 115:E9449-E9458. [PMID: 30224460 PMCID: PMC6176567 DOI: 10.1073/pnas.1804083115] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Normal neural development is essential for the formation of neuronal networks and brain function. Cutaneous T cell lymphoma-associated antigen 5 (cTAGE5)/meningioma expressed antigen 6 (MEA6) plays a critical role in the secretion of proteins. However, its roles in the transport of nonsecretory cellular components and in brain development remain unknown. Here, we show that cTAGE5/MEA6 is important for brain development and function. Conditional knockout of cTAGE5/MEA6 in the brain leads to severe defects in neural development, including deficits in dendrite outgrowth and branching, spine formation and maintenance, astrocyte activation, and abnormal behaviors. We reveal that loss of cTAGE5/MEA6 affects the interaction between the coat protein complex II (COPII) components, SAR1 and SEC23, leading to persistent activation of SAR1 and defects in COPII vesicle formation and transport from the endoplasmic reticulum to the Golgi, as well as disturbed trafficking of membrane components in neurons. These defects affect not only the transport of materials required for the development of dendrites and spines but also the signaling pathways required for neuronal development. Because mutations in cTAGE5/MEA6 have been found in patients with Fahr's disease, our study potentially also provides insight into the pathogenesis of this disorder.
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Affiliation(s)
- Feng Zhang
- State Key Laboratory of Molecular Developmental Biology, Chinese Academy of Sciences Center for Excellence in Brain Science and Intelligence Technology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101 Beijing, China
- University of Chinese Academy of Sciences, 100101 Beijing, China
| | - Yaqing Wang
- State Key Laboratory of Molecular Developmental Biology, Chinese Academy of Sciences Center for Excellence in Brain Science and Intelligence Technology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101 Beijing, China
- University of Chinese Academy of Sciences, 100101 Beijing, China
| | - Tao Wang
- State Key Laboratory of Molecular Developmental Biology, Chinese Academy of Sciences Center for Excellence in Brain Science and Intelligence Technology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101 Beijing, China
- University of Chinese Academy of Sciences, 100101 Beijing, China
| | - Li Yao
- State Key Laboratory of Cognitive Neuroscience & Learning, IDG/McGovern Institute for Brain Research, Beijing Normal University, 100875 Beijing, China
| | - Sin Man Lam
- State Key Laboratory of Molecular Developmental Biology, Chinese Academy of Sciences Center for Excellence in Brain Science and Intelligence Technology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101 Beijing, China
| | - Xiahe Huang
- State Key Laboratory of Molecular Developmental Biology, Chinese Academy of Sciences Center for Excellence in Brain Science and Intelligence Technology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101 Beijing, China
| | - Junwan Fan
- State Key Laboratory of Molecular Developmental Biology, Chinese Academy of Sciences Center for Excellence in Brain Science and Intelligence Technology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101 Beijing, China
- University of Chinese Academy of Sciences, 100101 Beijing, China
| | - Qin Wang
- State Key Laboratory of Molecular Developmental Biology, Chinese Academy of Sciences Center for Excellence in Brain Science and Intelligence Technology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101 Beijing, China
- University of Chinese Academy of Sciences, 100101 Beijing, China
| | - Liang Liu
- State Key Laboratory of Molecular Developmental Biology, Chinese Academy of Sciences Center for Excellence in Brain Science and Intelligence Technology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101 Beijing, China
- University of Chinese Academy of Sciences, 100101 Beijing, China
| | - Yisheng Jiang
- State Key Laboratory of Molecular Developmental Biology, Chinese Academy of Sciences Center for Excellence in Brain Science and Intelligence Technology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101 Beijing, China
- University of Chinese Academy of Sciences, 100101 Beijing, China
| | - Hongsheng Zhang
- State Key Laboratory of Molecular Developmental Biology, Chinese Academy of Sciences Center for Excellence in Brain Science and Intelligence Technology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101 Beijing, China
| | - Lei Shi
- State Key Laboratory of Molecular Developmental Biology, Chinese Academy of Sciences Center for Excellence in Brain Science and Intelligence Technology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101 Beijing, China
| | - Mei Yu
- State Key Laboratory of Molecular Developmental Biology, Chinese Academy of Sciences Center for Excellence in Brain Science and Intelligence Technology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101 Beijing, China
| | - Guanghou Shui
- State Key Laboratory of Molecular Developmental Biology, Chinese Academy of Sciences Center for Excellence in Brain Science and Intelligence Technology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101 Beijing, China
| | - Yingchun Wang
- State Key Laboratory of Molecular Developmental Biology, Chinese Academy of Sciences Center for Excellence in Brain Science and Intelligence Technology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101 Beijing, China
| | - Fei Gao
- State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences, 100101 Beijing, China
| | - Xiaohui Zhang
- State Key Laboratory of Cognitive Neuroscience & Learning, IDG/McGovern Institute for Brain Research, Beijing Normal University, 100875 Beijing, China
| | - Zhiheng Xu
- State Key Laboratory of Molecular Developmental Biology, Chinese Academy of Sciences Center for Excellence in Brain Science and Intelligence Technology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, 100101 Beijing, China;
- University of Chinese Academy of Sciences, 100101 Beijing, China
- Parkinson's Disease Center, Beijing Institute for Brain Disorders, 100101 Beijing, China
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Ogawa E, Mukai K, Saito K, Arai H, Taguchi T. The binding of TBK1 to STING requires exocytic membrane traffic from the ER. Biochem Biophys Res Commun 2018; 503:138-145. [PMID: 29870684 DOI: 10.1016/j.bbrc.2018.05.199] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Accepted: 05/29/2018] [Indexed: 10/14/2022]
Abstract
Stimulator of interferon genes (STING) is essential for the type I interferon and pro-inflammatory responses against DNA pathogens. In response to the presence of cytosolic DNA, STING translocates from the endoplasmic reticulum (ER) to the Golgi, and activates TANK-binding kinase 1 (TBK1), a cytosolic kinase that is essential for the activation of STING-dependent downstream signalling. The organelles where TBK1 binds to STING remain unknown. Here we show that TBK1 binds to STING at the Golgi, not at the ER. Treatment with brefeldin A, an agent to block ER-to-Golgi traffic, or knockdown of Sar1, a small GTPase that regulates coat protein complex II (COP-II)-mediated ER-to-Golgi traffic, inhibited the binding of TBK1 to STING. Endogenous TBK1 was recruited to the Golgi when STING was transported to the Golgi, as shown by immunofluorescence microscopy. STING variants that constitutively induce the type I interferon response were found in patients with autoinflammatory diseases. Even these disease-causative STING variants could not bind to TBK1 when the STING variants were trapped in the ER. These results demonstrate that the Golgi is an organelle at which STING recruits and activates TBK1 for triggering the STING-dependent type I interferon response.
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Affiliation(s)
- Emari Ogawa
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Kojiro Mukai
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Kota Saito
- Department of Biological Informatics and Experimental Therapeutics, Graduate School of Medicine, Akita University, Akita, 010-8543, Japan
| | - Hiroyuki Arai
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan; AMED-CREST, Japan Agency for Medical Research and Development, 1-7-1, Otemachi, Chiyoda-ku, Tokyo, 100-0004, Japan.
| | - Tomohiko Taguchi
- Department of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-0033, Japan; Laboratory of Organelle Pathophysiology, Department of Integrative Life Sciences, Graduate School of Life Sciences, Tohoku University, Aobayama, Aoba-ku, Sendai, Miyagi, 980-8578, Japan; AMED-PRIME, Japan Agency for Medical Research and Development, 1-7-1, Otemachi, Chiyoda-ku, Tokyo, 100-0004, Japan.
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44
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Binding of the GTPase Sar1 to a Lipid Membrane Monolayer: Insertion and Orientation Studied by Infrared Reflection⁻Absorption Spectroscopy. Polymers (Basel) 2017; 9:polym9110612. [PMID: 30965916 PMCID: PMC6418733 DOI: 10.3390/polym9110612] [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: 10/02/2017] [Revised: 10/26/2017] [Accepted: 11/06/2017] [Indexed: 01/15/2023] Open
Abstract
Membrane-interacting proteins are polyphilic polymers that engage in dynamic protein–protein and protein–lipid interactions while undergoing changes in conformation, orientation and binding interfaces. Predicting the sites of interactions between such polypeptides and phospholipid membranes is still a challenge. One example is the small eukaryotic GTPase Sar1, which functions in phospholipid bilayer remodeling and vesicle formation as part of the multimeric coat protein complex (COPII). The membrane interaction of Sar1 is strongly dependent on its N-terminal 23 amino acids. By monolayer adsorption experiments and infrared reflection-absorption spectroscopy (IRRAS), we elucidate the role of lipids in inducing the amphipathicity of this N-terminal stretch, which inserts into the monolayer as an amphipathic helix (AH). The AH inserting angle is determined and is consistent with the philicities and spatial distribution of the amino acid monomers. Using an advanced method of IRRAS data evaluation, the orientation of Sar1 with respect to the lipid layer prior to the recruitment of further COPII proteins is determined. The result indicates that only a slight reorientation of the membrane-bound Sar1 is needed to allow coat assembly. The time-course of the IRRAS analysis corroborates a role of slow GTP hydrolysis in Sar1 desorption from the membrane.
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45
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Herman E, Siegesmund MA, Bottery MJ, van Aerle R, Shather MM, Caler E, Dacks JB, van der Giezen M. Membrane Trafficking Modulation during Entamoeba Encystation. Sci Rep 2017; 7:12854. [PMID: 28993644 PMCID: PMC5634486 DOI: 10.1038/s41598-017-12875-6] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Accepted: 09/11/2017] [Indexed: 12/15/2022] Open
Abstract
Entamoeba histolytica is an intestinal parasite that infects 50-100 million people and causes up to 55,000 deaths annually. The transmissive form of E. histolytica is the cyst, with a single infected individual passing up to 45 million cysts per day, making cyst production an attractive target for infection control. Lectins and chitin are secreted to form the cyst wall, although little is known about the underlying membrane trafficking processes supporting encystation. As E. histolytica does not readily form cysts in vitro, we assessed membrane trafficking gene expression during encystation in the closely related model Entamoeba invadens. Genes involved in secretion are up-regulated during cyst formation, as are some trans-Golgi network-to-endosome trafficking genes. Furthermore, endocytic and general trafficking genes are up-regulated in the mature cyst, potentially preserved as mRNA in preparation for excystation. Two divergent dynamin-related proteins found in Entamoeba are predominantly expressed during cyst formation. Phylogenetic analyses indicate that they are paralogous to, but quite distinct from, classical dynamins found in human, suggesting that they may be potential drug targets to block encystation. The membrane-trafficking machinery is clearly regulated during encystation, providing an additional facet to understanding this crucial parasitic process.
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Affiliation(s)
- Emily Herman
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, T6G 2H7, Edmonton, Alberta, Canada
| | | | - Michael J Bottery
- Department of Biology, University of York, Heslington, York, YO10 5DD, UK
| | - Ronny van Aerle
- Biosciences, University of Exeter, Stocker Road, Exeter, EX4 4QD, UK
- Centre for Environment, Fisheries, and Aquaculture Science (Cefas), Barrack Road, The Nothe, Weymouth, Dorset, DT4 8UB, UK
| | | | - Elisabet Caler
- J. Craig Venter Institute, 9714 Medical Center Drive, Rockville, MD, 20850, USA
- National Heart, Lung, and Blood Institute (NHLBI), National Institutes of Health (NIH), 6701, Rockledge Drive, Room 9144, Bethesda, MD, 20892-7950, USA
| | - Joel B Dacks
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, T6G 2H7, Edmonton, Alberta, Canada.
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Saito K, Maeda M, Katada T. Regulation of the Sar1 GTPase Cycle Is Necessary for Large Cargo Secretion from the Endoplasmic Reticulum. Front Cell Dev Biol 2017; 5:75. [PMID: 28879181 PMCID: PMC5572378 DOI: 10.3389/fcell.2017.00075] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 08/10/2017] [Indexed: 12/22/2022] Open
Abstract
Proteins synthesized within the endoplasmic reticulum (ER) are transported to the Golgi via coat protein complex II (COPII)-coated vesicles. The formation of COPII-coated vesicles is regulated by the GTPase cycle of Sar1. Activated Sar1 is recruited to ER membranes and forms a pre-budding complex with cargoes and the inner-coat complex. The outer-coat complex then stimulates Sar1 inactivation and completes vesicle formation. The mechanisms of forming transport carriers are well-conserved among species; however, in mammalian cells, several cargo molecules such as collagen, and chylomicrons are too large to be accommodated in conventional COPII-coated vesicles. Thus, special cargo-receptor complexes are required for their export from the ER. cTAGE5/TANGO1 complexes and their isoforms have been identified as cargo receptors for these macromolecules. Recent reports suggest that the cTAGE5/TANGO1 complex interacts with the GEF and the GAP of Sar1 and tightly regulates its GTPase cycle to accomplish large cargo secretion.
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Affiliation(s)
- Kota Saito
- Department of Physiological Chemistry, Graduate School of Pharmaceutical Sciences, University of TokyoTokyo, Japan
| | - Miharu Maeda
- Department of Physiological Chemistry, Graduate School of Pharmaceutical Sciences, University of TokyoTokyo, Japan
| | - Toshiaki Katada
- Department of Physiological Chemistry, Graduate School of Pharmaceutical Sciences, University of TokyoTokyo, Japan
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Iwasaki H, Yorimitsu T, Sato K. Microscopy analysis of reconstituted COPII coat polymerization and Sec16 dynamics. J Cell Sci 2017; 130:2893-2902. [PMID: 28747320 DOI: 10.1242/jcs.203844] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 07/14/2017] [Indexed: 01/10/2023] Open
Abstract
The COPII coat and the small GTPase Sar1 mediate protein export from the endoplasmic reticulum (ER) via specialized domains known as the ER exit sites. The peripheral ER protein Sec16 has been proposed to organize ER exit sites. However, it remains unclear how these molecules drive COPII coat polymerization. Here, we characterized the spatiotemporal relationships between the Saccharomyces cerevisiae COPII components during their polymerization by performing fluorescence microscopy of an artificial planar membrane. We demonstrated that Sar1 dissociates from the membrane shortly after the COPII coat recruitment, and Sar1 is then no longer required for the COPII coat to bind to the membrane. Furthermore, we found that Sec16 is incorporated within the COPII-cargo clusters, and that this is dependent on the Sar1 GTPase cycle. These data show how Sar1 drives the polymerization of COPII coat and how Sec16 is spatially distributed during COPII coat polymerization.
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Affiliation(s)
- Hirohiko Iwasaki
- Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
| | - Tomohiro Yorimitsu
- Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
| | - Ken Sato
- Department of Life Sciences, Graduate School of Arts and Sciences, University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902, Japan
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Brandizzi F. Transport from the endoplasmic reticulum to the Golgi in plants: Where are we now? Semin Cell Dev Biol 2017; 80:94-105. [PMID: 28688928 DOI: 10.1016/j.semcdb.2017.06.024] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2017] [Revised: 05/11/2017] [Accepted: 06/27/2017] [Indexed: 11/26/2022]
Abstract
The biogenesis of about one third of the cellular proteome is initiated in the endoplasmic reticulum (ER), which exports proteins to the Golgi apparatus for sorting to their final destination. Notwithstanding the close proximity of the ER with other secretory membranes (e.g., endosomes, plasma membrane), the ER is also important for the homeostasis of non-secretory organelles such as mitochondria, peroxisomes, and chloroplasts. While how the plant ER interacts with most of the non-secretory membranes is largely unknown, the knowledge on the mechanisms for ER-to-Golgi transport is relatively more advanced. Indeed, over the last fifteen years or so, a large number of exciting results have contributed to draw parallels with non-plant species but also to highlight the complexity of the plant ER-Golgi interface, which bears unique features. This review reports and discusses results on plant ER-to-Golgi traffic, focusing mainly on research on COPII-mediated transport in the model species Arabidopsis thaliana.
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Affiliation(s)
- Federica Brandizzi
- MSU-DOE Plant Research Lab and Plant Biology Department, Michigan State University, East Lansing, MI 48824, USA; Department of Plant Biology, Michigan State University, East Lansing, MI 48824, USA; Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI 48824, USA.
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Moderate Expression of SEC16 Increases Protein Secretion by Saccharomyces cerevisiae. Appl Environ Microbiol 2017; 83:AEM.03400-16. [PMID: 28476767 DOI: 10.1128/aem.03400-16] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 04/27/2017] [Indexed: 12/21/2022] Open
Abstract
The yeast Saccharomyces cerevisiae is widely used to produce biopharmaceutical proteins. However, the limited capacity of the secretory pathway may reduce its productivity. Here, we increased the secretion of a heterologous α-amylase, a model protein used for studying the protein secretory pathway in yeast, by moderately overexpressing SEC16, which is involved in protein translocation from the endoplasmic reticulum to the Golgi apparatus. The moderate overexpression of SEC16 increased α-amylase secretion by generating more endoplasmic reticulum exit sites. The production of reactive oxygen species resulting from the heterologous α-amylase production was reduced. A genome-wide expression analysis indicated decreased endoplasmic reticulum stress in the strain that moderately overexpressed SEC16, which was consistent with a decreased volume of the endoplasmic reticulum. Additionally, fewer mitochondria were observed. Finally, the moderate overexpression of SEC16 was shown to improve the secretion of two other recombinant proteins, Trichoderma reesei endoglucanase I and Rhizopus oryzae glucan-1,4-α-glucosidase, indicating that this mechanism is of general relevance.IMPORTANCE There is an increasing demand for recombinant proteins to be used as enzymes and pharmaceuticals. The yeast Saccharomyces cerevisiae is a cell factory that is widely used to produce recombinant proteins. Our study revealed that moderate overexpression of SEC16 increased recombinant protein secretion in S. cerevisiae This new strategy can be combined with other targets to engineer cell factories to efficiently produce protein in the future.
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50
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Parashar S, Mukhopadhyay A. GTPase Sar1 regulates the trafficking and secretion of the virulence factor gp63 in Leishmania. J Biol Chem 2017; 292:12111-12125. [PMID: 28576830 DOI: 10.1074/jbc.m117.784033] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 05/30/2017] [Indexed: 12/30/2022] Open
Abstract
Metalloprotease gp63 (Leishmania donovani gp63 (Ldgp63)) is a critical virulence factor secreted by Leishmania However, how newly synthesized Ldgp63 exits the endoplasmic reticulum (ER) and is secreted by this parasite is unknown. Here, we cloned, expressed, and characterized the GTPase LdSar1 and other COPII components like LdSec23, LdSec24, LdSec13, and LdSec31 from Leishmania to understand their role in ER exit of Ldgp63. Using dominant-positive (LdSar1:H74L) and dominant-negative (LdSar1:T34N) mutants of LdSar1, we found that GTP-bound LdSar1 specifically binds to LdSec23, which binds, in turn, with LdSec24(1-702) to form a prebudding complex. Moreover, LdSec13 specifically interacted with His6-LdSec31(1-603), and LdSec31 bound the prebudding complex via LdSec23. Interestingly, dileucine 594/595 and valine 597 residues present in the Ldgp63 C-terminal domain were critical for binding with LdSec24(703-966), and GFP-Ldgp63L594A/L595A or GFP-Ldgp63V597S mutants failed to exit from the ER. Moreover, Ldgp63-containing COPII vesicle budding from the ER was inhibited by LdSar1:T34N in an in vitro budding assay, indicating that GTP-bound LdSar1 is required for budding of Ldgp63-containing COPII vesicles. To directly demonstrate the function of LdSar1 in Ldgp63 trafficking, we coexpressed RFP-Ldgp63 along with LdSar1:WT-GFP or LdSar1:T34N-GFP and found that LdSar1:T34N overexpression blocks Ldgp63 trafficking and secretion in Leishmania Finally, we noted significantly compromised survival of LdSar1:T34N-GFP-overexpressing transgenic parasites in macrophages. Taken together, these results indicated that Ldgp63 interacts with the COPII complex via LdSec24 for Ldgp63 ER exit and subsequent secretion.
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Affiliation(s)
- Smriti Parashar
- National Institute of Immunology, Aruna Asaf Ali Marg, New Delhi 110067, India
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