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Comparison of the Cisterna Maturation-Progression Model with the Kiss-and-Run Model of Intra-Golgi Transport: Role of Cisternal Pores and Cargo Domains. Int J Mol Sci 2022; 23:ijms23073590. [PMID: 35408951 PMCID: PMC8999060 DOI: 10.3390/ijms23073590] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 03/11/2022] [Accepted: 03/16/2022] [Indexed: 12/22/2022] Open
Abstract
The Golgi complex is the central station of the secretory pathway. Knowledge about the mechanisms of intra-Golgi transport is inconsistent. Here, we compared the explanatory power of the cisterna maturation-progression model and the kiss-and-run model. During intra-Golgi transport, conventional cargoes undergo concentration and form cisternal distensions or distinct membrane domains that contain only one membrane cargo. These domains and distension are separated from the rest of the Golgi cisternae by rows of pores. After the arrival of any membrane cargo or a large cargo aggregate at the Golgi complex, the cis-Golgi SNAREs become enriched within the membrane of cargo-containing domains and then replaced by the trans-Golgi SNAREs. During the passage of these domains, the number of cisternal pores decreases. Restoration of the cisternal pores is COPI-dependent. Our observations are more in line with the kiss-and-run model.
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Kim JJ, Lipatova Z, Segev N. Establishing Regulation of a Dynamic Process by Ypt/Rab GTPases : A Case for Cisternal Progression. Methods Mol Biol 2021; 2293:189-199. [PMID: 34453718 DOI: 10.1007/978-1-0716-1346-7_13] [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] [Indexed: 06/13/2023]
Abstract
The prevailing model for transport within the Golgi is cisternal maturation. This process can be viewed as switching of cisternal markers using live-cell microscopy in yeast cells since the Golgi cisternae are separated, as opposed to the stacked Golgi seen in other organisms. It is also possible to determine which trafficking machinery components are required for this process by studying mutants depleted for these components. However, determining how cisternal maturation is regulated has been more challenging. The key for demonstrating regulation is not solely to stop the maturation when depleting a vesicular trafficking component, but also to illustrate a change in the speed. The obvious candidates for such regulation are the Ypt/Rab GTPases because of their established mode of action as regulators. Since the precise localization of the Golgi Ypts, Ypt1 and Ypt31, to specific Golgi cisternae has been controversial, we started by carefully colocalizing these Ypts with the Golgi cisternal markers using two independent approaches: immunofluorescence and live-cell microscopy. Next, the opposite effects of depletion versus constitutively activating Ypt mutations on Golgi morphology were determined. Finally, the ability of constitutively activating Ypt mutations to accelerate a specific cisternal-maturation step was established by live-cell time-lapse microscopy. Using these approaches, we defined three dynamic Golgi cisternae, early, intermediate, and late, separated two independent steps of cisternal maturation and showed their regulation by two different Ypts. Here, we discuss the major principles and precautions needed for each phase of this research, the main point being definition of a new criterion for regulation of a dynamic process versus requirement of a machinery structural component: acceleration of the dynamics.
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Affiliation(s)
- Jane J Kim
- Department of Biochemistry and Molecular Genetics, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Zanna Lipatova
- Department of Biochemistry and Molecular Genetics, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA
| | - Nava Segev
- Department of Biochemistry and Molecular Genetics, College of Medicine, University of Illinois at Chicago, Chicago, IL, USA.
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3
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Mironov AA, Beznoussenko GV. Models of Intracellular Transport: Pros and Cons. Front Cell Dev Biol 2019; 7:146. [PMID: 31440506 PMCID: PMC6693330 DOI: 10.3389/fcell.2019.00146] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 07/16/2019] [Indexed: 12/22/2022] Open
Abstract
Intracellular transport is one of the most confusing issues in the field of cell biology. Many different models and their combinations have been proposed to explain the experimental data on intracellular transport. Here, we analyse the data related to the mechanisms of endoplasmic reticulum-to-Golgi and intra-Golgi transport from the point of view of the main models of intracellular transport; namely: the vesicular model, the diffusion model, the compartment maturation–progression model, and the kiss-and-run model. This review initially describes our current understanding of Golgi function, while highlighting the recent progress that has been made. It then continues to discuss the outstanding questions and potential avenues for future research with regard to the models of these transport steps. To compare the power of these models, we have applied the method proposed by K. Popper; namely, the formulation of prohibitive observations according to, and the consecutive evaluation of, previous data, on the basis on the new models. The levels to which the different models can explain the experimental observations are different, and to date, the most powerful has been the kiss-and-run model, whereas the least powerful has been the diffusion model.
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Affiliation(s)
- Alexander A Mironov
- Department of Cell Biology, The FIRC Institute of Molecular Oncology, Milan, Italy
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4
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Mironov AA, Dimov ID, Beznoussenko GV. Role of Intracellular Transport in the Centriole-Dependent Formation of Golgi Ribbon. Results Probl Cell Differ 2019; 67:49-79. [PMID: 31435792 DOI: 10.1007/978-3-030-23173-6_4] [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] [Indexed: 12/15/2022]
Abstract
The intracellular transport is the most confusing issue in the field of cell biology. The Golgi complex (GC) is the central station along the secretory pathway. It contains Golgi glycosylation enzymes, which are responsible for protein and lipid glycosylation, and in many cells, it is organized into a ribbon. Position and structure of the GC depend on the position and function of the centriole. Here, we analyze published data related to the role of centriole and intracellular transport (ICT) for the formation of Golgi ribbon and specifically stress the importance of the delivery of membranes containing cargo and membrane proteins to the cell centre where centriole/centrosome is localized. Additionally, we re-examined the formation of Golgi ribbon from the point of view of different models of ICT.
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Affiliation(s)
| | - Ivan D Dimov
- Department of Anatomy, Saint Petersburg State Paediatric Medical University, Saint Petersburg, Russia
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5
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Different Golgi ultrastructure across species and tissues: Implications under functional and pathological conditions, and an attempt at classification. Tissue Cell 2017; 49:186-201. [DOI: 10.1016/j.tice.2016.12.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Revised: 12/05/2016] [Accepted: 12/05/2016] [Indexed: 02/08/2023]
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6
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Beznoussenko GV, Parashuraman S, Rizzo R, Polishchuk R, Martella O, Di Giandomenico D, Fusella A, Spaar A, Sallese M, Capestrano MG, Pavelka M, Vos MR, Rikers YGM, Helms V, Mironov AA, Luini A. Transport of soluble proteins through the Golgi occurs by diffusion via continuities across cisternae. eLife 2014; 3:e02009. [PMID: 24867214 PMCID: PMC4070021 DOI: 10.7554/elife.02009] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 05/25/2014] [Indexed: 12/18/2022] Open
Abstract
The mechanism of transport through the Golgi complex is not completely understood, insofar as no single transport mechanism appears to account for all of the observations. Here, we compare the transport of soluble secretory proteins (albumin and α1-antitrypsin) with that of supramolecular cargoes (e.g., procollagen) that are proposed to traverse the Golgi by compartment progression-maturation. We show that these soluble proteins traverse the Golgi much faster than procollagen while moving through the same stack. Moreover, we present kinetic and morphological observations that indicate that albumin transport occurs by diffusion via intercisternal continuities. These data provide evidence for a transport mechanism that applies to a major class of secretory proteins and indicate the co-existence of multiple intra-Golgi trafficking modes.
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Affiliation(s)
- Galina V Beznoussenko
- Fondazione IFOM, Istituto FIRC di Oncologia Molecolare (IFOM-IEO Campus), Milan, Italy
- Department of Cell Biology and Oncology, Consorzio Mario Negri Sud, Santa Maria Imbaro, Italy
| | - Seetharaman Parashuraman
- Department of Cell Biology and Oncology, Consorzio Mario Negri Sud, Santa Maria Imbaro, Italy
- Institute of Protein Biochemistry, Consiglio Nazionale Delle Ricerche (CNR-IBP), Naples, Italy
| | - Riccardo Rizzo
- Institute of Protein Biochemistry, Consiglio Nazionale Delle Ricerche (CNR-IBP), Naples, Italy
| | - Roman Polishchuk
- Department of Cell Biology and Oncology, Consorzio Mario Negri Sud, Santa Maria Imbaro, Italy
- Telethon Institute for Genetics and Medicine (TIGEM), Naples, Italy
| | - Oliviano Martella
- Department of Cell Biology and Oncology, Consorzio Mario Negri Sud, Santa Maria Imbaro, Italy
| | - Daniele Di Giandomenico
- Department of Cell Biology and Oncology, Consorzio Mario Negri Sud, Santa Maria Imbaro, Italy
| | - Aurora Fusella
- Department of Cell Biology and Oncology, Consorzio Mario Negri Sud, Santa Maria Imbaro, Italy
| | - Alexander Spaar
- Department of Cell Biology and Oncology, Consorzio Mario Negri Sud, Santa Maria Imbaro, Italy
| | - Michele Sallese
- Department of Cell Biology and Oncology, Consorzio Mario Negri Sud, Santa Maria Imbaro, Italy
| | - Maria Grazia Capestrano
- Department of Cell Biology and Oncology, Consorzio Mario Negri Sud, Santa Maria Imbaro, Italy
| | - Margit Pavelka
- Department of Cell Biology and Ultrastructure Research, Center for Anatomy and Cell Biology, Medical University of Vienna, Vienna, Austria
| | | | | | - Volkhard Helms
- Center for Bioinformatics, Saarland University, Saarbruecken, Germany
| | - Alexandre A Mironov
- Fondazione IFOM, Istituto FIRC di Oncologia Molecolare (IFOM-IEO Campus), Milan, Italy
| | - Alberto Luini
- Department of Cell Biology and Oncology, Consorzio Mario Negri Sud, Santa Maria Imbaro, Italy
- Institute of Protein Biochemistry, Consiglio Nazionale Delle Ricerche (CNR-IBP), Naples, Italy
- Telethon Institute for Genetics and Medicine (TIGEM), Naples, Italy
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7
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Mironov AA, Sesorova IV, Beznoussenko GV. Golgi's way: a long path toward the new paradigm of the intra-Golgi transport. Histochem Cell Biol 2013; 140:383-93. [PMID: 24068461 DOI: 10.1007/s00418-013-1141-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/03/2013] [Indexed: 11/28/2022]
Abstract
The transport of proteins and lipids is one of the main cellular functions. The vesicular model, compartment (or cisterna) maturation model, and the diffusion model compete with each other for the right to be the paradigm within the field of the intra-Golgi transport. These models have significant difficulties explaining the existing experimental data. Recently, we proposed the kiss-and-run (KAR) model of intra-Golgi transport (Mironov and Beznoussenko in Int J Mol Sci 13(6):6800-6819, 2012), which can be symmetric, when fusion and fission occur in the same location, and asymmetric, when fusion and fission take place at different sites. Here, we compare the ability of main models of the intra-Golgi transport to explain the existing results examining the evidence in favor and against each model. We propose that the KAR model has the highest potential for the explanation of the majority of experimental observations existing within the field of intracellular transport.
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Affiliation(s)
- Alexander A Mironov
- Istituto di Oncologia Molecolare di Fondazione Italiana per la Ricerca sul Cancro, 20139, Milan, Italy,
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9
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Fusella A, Micaroni M, Di Giandomenico D, Mironov AA, Beznoussenko GV. Segregation of the Qb-SNAREs GS27 and GS28 into Golgi vesicles regulates intra-Golgi transport. Traffic 2013; 14:568-84. [PMID: 23387339 DOI: 10.1111/tra.12055] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 01/31/2013] [Accepted: 02/06/2013] [Indexed: 12/18/2022]
Abstract
The Golgi apparatus is the main glycosylation and sorting station along the secretory pathway. Its structure includes the Golgi vesicles, which are depleted of anterograde cargo, and also of at least some Golgi-resident proteins. The role of Golgi vesicles remains unclear. Here, we show that Golgi vesicles are enriched in the Qb-SNAREs GS27 (membrin) and GS28 (GOS-28), and depleted of nucleotide sugar transporters. A block of intra-Golgi transport leads to accumulation of Golgi vesicles and partitioning of GS27 and GS28 into these vesicles. Conversely, active intra-Golgi transport induces fusion of these vesicles with the Golgi cisternae, delivering GS27 and GS28 to these cisternae. In an in vitro assay based on a donor compartment that lacks UDP-galactose translocase (a sugar transporter), the segregation of Golgi vesicles from isolated Golgi membranes inhibits intra-Golgi transport; re-addition of isolated Golgi vesicles devoid of UDP-galactose translocase obtained from normal cells restores intra-Golgi transport. We conclude that this activity is due to the presence of GS27 and GS28 in the Golgi vesicles, rather than the sugar transporter. Furthermore, there is an inverse correlation between the number of Golgi vesicles and the number of inter-cisternal connections under different experimental conditions. Finally, a rapid block of the formation of vesicles via COPI through degradation of ϵCOP accelerates the cis-to-trans delivery of VSVG. These data suggest that Golgi vesicles, presumably with COPI, serve to inhibit intra-Golgi transport by the extraction of GS27 and GS28 from the Golgi cisternae, which blocks the formation of inter-cisternal connections.
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Affiliation(s)
- Aurora Fusella
- Consorzio Mario Negri Sud, Via Nazionale 8, 66030, Santa Maria Imbaro (Chieti), Italy
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10
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Mironov AA, Beznoussenko GV. The kiss-and-run model of intra-Golgi transport. Int J Mol Sci 2012; 13:6800-6819. [PMID: 22837664 PMCID: PMC3397496 DOI: 10.3390/ijms13066800] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2012] [Revised: 05/09/2012] [Accepted: 05/22/2012] [Indexed: 11/16/2022] Open
Abstract
The Golgi apparatus (GA) is the main station along the secretory pathway. Mechanisms of intra-Golgi transport remain unresolved. Three models compete with each other for the right to be defined as the paradigm. The vesicular model cannot explain the following: (1) lipid droplets and aggregates of procollagen that are larger than coatomer I (COPI)-dependent vesicles are transported across the GA; and (2) most anterograde cargoes are depleted in COPI vesicles. The compartment progression/maturation model has the following problems: (1) most Golgi-resident proteins are depleted in COPI vesicles; (2) there are no COPI vesicles for the recycling of the resident proteins in the trans-most-Golgi cisterna; and (3) different proteins have different rates of intra-Golgi transport. The diffusion model based on permanent inter-cisternal connections cannot explain the existence of lipid, ionic and protein gradients across the Golgi stacks. In contrast, the kiss-and-run model has the potential to explain most of the experimental observations. The kiss-and-run model can be symmetric when fusion and then fission occurs in the same place, and asymmetric when fusion takes place in one location, whereas fission takes place in another. The asymmetric kiss-and-run model resembles the carrier maturation mechanism, and it can be used to explain the transport of large cargo aggregates.
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Affiliation(s)
- Alexander A. Mironov
- IFOM Foundation, FIRC Institute of Molecular Oncology (IFOM-IEO Campus), Via Adamello 16, 20139, Milan, Italy
| | - Galina V. Beznoussenko
- IFOM Foundation, FIRC Institute of Molecular Oncology (IFOM-IEO Campus), Via Adamello 16, 20139, Milan, Italy
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11
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Abstract
A variety of secretory cargoes move through the Golgi, but the pathways and mechanisms of this traffic are still being debated. Here, we evaluate the strengths and weaknesses of five current models for Golgi traffic: (1) anterograde vesicular transport between stable compartments, (2) cisternal progression/maturation, (3) cisternal progression/maturation with heterotypic tubular transport, (4) rapid partitioning in a mixed Golgi, and (5) stable compartments as cisternal progenitors. Each model is assessed for its ability to explain a set of key observations encompassing multiple cell types. No single model can easily explain all of the observations from diverse organisms. However, we propose that cisternal progression/maturation is the best candidate for a conserved core mechanism of Golgi traffic, and that some cells elaborate this core mechanism by means of heterotypic tubular transport between cisternae.
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Affiliation(s)
- Benjamin S Glick
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois 60637, USA.
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12
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Conserved molecular mechanisms underlying homeostasis of the Golgi complex. Int J Cell Biol 2010; 2010:758230. [PMID: 20976261 PMCID: PMC2952910 DOI: 10.1155/2010/758230] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2010] [Revised: 07/30/2010] [Accepted: 08/19/2010] [Indexed: 01/16/2023] Open
Abstract
The Golgi complex performs a central function in the secretory pathway in the sorting and sequential processing of a large number of proteins destined for other endomembrane organelles, the plasma membrane, or secretion from the cell, in addition to lipid metabolism and signaling. The Golgi apparatus can be regarded as a self-organizing system that maintains a relatively stable morphofunctional organization in the face of an enormous flux of lipids and proteins. A large number of the molecular players that operate in these processes have been identified, their functions and interactions defined, but there is still debate about many aspects that regulate protein trafficking and, in particular, the maintenance of these highly dynamic structures and processes. Here, we consider how an evolutionarily conserved underlying mechanism based on retrograde trafficking that uses lipids, COPI, SNAREs, and tethers could maintain such a homeodynamic system.
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Perinetti G, Müller T, Spaar A, Polishchuk R, Luini A, Egner A. Correlation of 4Pi and electron microscopy to study transport through single Golgi stacks in living cells with super resolution. Traffic 2009; 10:379-91. [PMID: 19170980 DOI: 10.1111/j.1600-0854.2008.00875.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Two problems have hampered the use of light microscopy for structural studies of cellular organelles for a long time: the limited resolution and the difficulty of obtaining true structural boundaries from complex intensity curves. The advent of modern high-resolution light microscopy techniques and their combination with objective image segmentation now provide us with the means to bridge the gap between light and electronmicroscopy in cell biology applications. In this study, we provide the first comparative correlative analysis of three-dimensional structures obtained by 4Pi microscopy and segmented by a zero-crossing procedure with those of transmission electron microscopy (TEM). The distribution within the cisternae of isolated Golgi stacks of the cargo protein procollagen 3 was mapped by both 4Pi microscopy and TEM for a detailed comparative analysis of their imaging capabilities. A high correlation was seen for the structures, indicating the particular accuracy of the 4Pi microscopy. Furthermore, for the first time, transport of a cargo molecule (vesicular stomatitis virus G protein-pEGFP) through individual Golgi stacks (labeled by galactosyl transferase-venus-YFP) was visualized by 4Pi microscopy. Following the procedures validated by the correlative analysis, our transport experiments show that (i) VSVG-pEGFP rapidly enter/exit individual Golgi stacks, (ii) VSVG-pEGFP never fills the GalT-venusYFP compartments completely and (iii) the GalT-venusYFP compartment volume increases upon VSVG-pEGFP arrival. This morphological evidence supports some previous TEM-based observations of intra-Golgi transport of VSVG-pEGFP and provides new insights toward a better understanding of protein progression across Golgi stacks. Our study thus demonstrates the general applicability of super resolution fluorescence microscopy, coupled with the zero-crossing segmentation procedure, for structural studies of suborganelle protein distributions under living cell conditions.
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Affiliation(s)
- Giuseppe Perinetti
- Department of Cell Biology and Oncology, Consorzio Mario Negri Sud, Santa Maria Imbaro (CH), Italy.
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Langer I, Leroy K, Gaspard N, Brion JP, Robberecht P. Cell surface targeting of VPAC1 receptors: evidence for implication of a quality control system and the proteasome. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2008; 1783:1663-72. [PMID: 18435935 DOI: 10.1016/j.bbamcr.2008.03.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2008] [Revised: 03/18/2008] [Accepted: 03/19/2008] [Indexed: 11/15/2022]
Abstract
Like for most transmembrane proteins, translation of G protein-coupled receptors (GPCRs) mRNA takes place at the endoplasmic reticulum (ER) where they are synthesized, folded and assembled. The molecular mechanisms involved in the transport process of GPCRs from ER to the plasma membrane are poorly investigated. Here we studied the mechanisms involved in glycosylation-dependent cell surface expression and quality control of the receptor for Vasoactive Intestinal Polypeptide (VIP) VPAC1, a member of the B family of GPCRs. Using biochemical and pharmacological techniques and fluorescence microscopy, we have shown that only a fraction of newly synthesized VPAC1 attains properly conformation that allows their cell surface targeting. Misfolded or immature VPAC1 are taken in charge by co- and post-translational quality control that involves: 1) calnexin-dependent folding strictly through a glycan-dependent mechanism, 2) BiP-dependant folding, 3) translocation to the cytoplasm and proteasome-dependent degradation of improper proteins, and 4) post-ER quality control check points. Our data suggest that VPAC1 expression/trafficking pathways are under the control of complex and precise molecular mechanisms to ensure that only proper VPAC1 reaches the cell surface.
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Affiliation(s)
- Ingrid Langer
- Laboratory of Biological Chemistry and Nutrition, School of Medicine, Université Libre de Bruxelles, 808 route de Lennik CP611, B-1070 Brussels, Belgium.
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Pavelka M, Neumüller J, Ellinger A. Retrograde traffic in the biosynthetic-secretory route. Histochem Cell Biol 2008; 129:277-88. [PMID: 18270728 PMCID: PMC2248610 DOI: 10.1007/s00418-008-0383-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/09/2008] [Indexed: 02/04/2023]
Abstract
In the biosynthetic-secretory route from the rough endoplasmic reticulum, across the pre-Golgi intermediate compartments, the Golgi apparatus stacks, trans Golgi network, and post-Golgi organelles, anterograde transport is accompanied and counterbalanced by retrograde traffic of both membranes and contents. In the physiologic dynamics of cells, retrograde flow is necessary for retrieval of molecules that escaped from their compartments of function, for keeping the compartments' balances, and maintenance of the functional integrities of organelles and compartments along the secretory route, for repeated use of molecules, and molecule repair. Internalized molecules may be transported in retrograde direction along certain sections of the secretory route, and compartments and machineries of the secretory pathway may be misused by toxins. An important example is the toxin of Shigella dysenteriae, which has been shown to travel from the cell surface across endosomes, and the Golgi apparatus en route to the endoplasmic reticulum, and the cytosol, where it exerts its deleterious effects. Most importantly in medical research, knowledge about the retrograde cellular pathways is increasingly being utilized for the development of strategies for targeted delivery of drugs to the interior of cells. Multiple details about the molecular transport machineries involved in retrograde traffic are known; a high number of the molecular constituents have been characterized, and the complicated fine structural architectures of the compartments involved become more and more visible. However, multiple contradictions exist, and already established traffic models again are in question by contradictory results obtained with diverse cell systems, and/or different techniques. Additional problems arise by the fact that the conditions used in the experimental protocols frequently do not reflect the physiologic situations of the cells. Regular and pathologic situations often are intermingled, and experimental treatments by themselves change cell organizations. This review addresses physiologic and pathologic situations, tries to correlate results obtained by different cell biologic techniques, and asks questions, which may be the basis and starting point for further investigations.
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Affiliation(s)
- Margit Pavelka
- Department of Cell Biology and Ultrastructure Research, Center for Anatomy and Cell Biology, Medical University of Vienna, Schwarzspanierstrasse 17, Vienna, Austria.
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16
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Wang Y, Wei JH, Bisel B, Tang D, Seemann J. Golgi cisternal unstacking stimulates COPI vesicle budding and protein transport. PLoS One 2008; 3:e1647. [PMID: 18297130 PMCID: PMC2249924 DOI: 10.1371/journal.pone.0001647] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2007] [Accepted: 01/28/2008] [Indexed: 11/19/2022] Open
Abstract
The Golgi apparatus in mammalian cells is composed of flattened cisternae that are densely packed to form stacks. We have used the Golgi stacking protein GRASP65 as a tool to modify the stacking state of Golgi cisternae. We established an assay to measure protein transport to the cell surface in post-mitotic cells in which the Golgi was unstacked. Cells with an unstacked Golgi showed a higher transport rate compared to cells with stacked Golgi membranes. Vesicle budding from unstacked cisternae in vitro was significantly increased compared to stacked membranes. These results suggest that Golgi cisternal stacking can directly regulate vesicle formation and thus the rate of protein transport through the Golgi. The results further suggest that at the onset of mitosis, unstacking of cisternae allows extensive and rapid vesiculation of the Golgi in preparation for its subsequent partitioning.
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Affiliation(s)
- Yanzhuang Wang
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Jen-Hsuan Wei
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Blaine Bisel
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
| | - Danming Tang
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan, United States of America
| | - Joachim Seemann
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, Texas, United States of America
- *E-mail:
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17
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Zhao W, Colley KJ. Nucleotide sugar transporters of the Golgi apparatus. THE GOLGI APPARATUS 2008. [PMCID: PMC7119966 DOI: 10.1007/978-3-211-76310-0_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
The Golgi apparatus is the major site of protein, lipid and proteoglycan glycosylation. The glycosylation enzymes, as well as kinases and sulfatases that catalyze phosphorylation and sulfation, are localized within the Golgi cisternae in characteristic distributions that frequently reflect their order in a particular pathway (Kornfeld and Kornfeld 1985; Colley 1997). The glycosyl-transferases, sulfotransferases and kinases are “transferases” that require activated donor molecules for the reactions they catalyze. For eukaryotic, fungal and protozoan glycosyltransferases these are the nucleotide sugars UDP-N-acetylglucosamine (UDP-GlcNAc), UDP-galactose (UDP-Gal), GDP-fucose (GDP-Fuc), CMP-sialicacid (CMP-Sia), UDP-glucuronicacid (UDP-GlcA), GDP-mannose (GDP-Man), and UDP-xylose (UDP-Xyl) (Hirschberg et al. 1998). For the kinases, ATP functions as the donor, while for the sulfotransferases, adenosine 3′-phosphate 5′-phosphate (PAPS) acts as the donor (Hirschberg et al. 1998). The active sites of all these enzymes are oriented towards the lumen of the Golgi cisternae. This necessitates the translocation of their donors from the cytosol into the lumenal Golgi compartments. In this chapter we will focus on the structure, function and localization of the Golgi nucleotide sugar transporters (NSTs), and highlight the diseases and developmental defects associated with defective transporters. We direct the reader to several excellent reviews on Golgi transporters for additional details and references (Hirschberg et al. 1998; Berninsone and Hirschberg 2000; Gerardy-Schahn et al. 2001; Handford et al. 2006; Caffaro and Hirschberg 2006).
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Derganc J. Curvature-driven lateral segregation of membrane constituents in Golgi cisternae. Phys Biol 2007; 4:317-24. [DOI: 10.1088/1478-3975/4/4/008] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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19
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Yamane J, Kubo A, Nakayama K, Yuba-Kubo A, Katsuno T, Tsukita S, Tsukita S. Functional involvement of TMF/ARA160 in Rab6-dependent retrograde membrane traffic. Exp Cell Res 2007; 313:3472-85. [PMID: 17698061 DOI: 10.1016/j.yexcr.2007.07.010] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2007] [Revised: 07/10/2007] [Accepted: 07/10/2007] [Indexed: 12/28/2022]
Abstract
The small GTPase Rab6 regulates retrograde membrane traffic from endosomes to the Golgi apparatus and from the Golgi to the endoplasmic reticulum (ER). We examined the role of a Rab6-binding protein, TMF/ARA160 (TATA element modulatory factor/androgen receptor-coactivator of 160 kDa), in this process. High-resolution immunofluorescence imaging revealed that TMF signal surrounded Rab6-positive Golgi structures and immunoelectron microscopy revealed that TMF is concentrated at the budding structures localized at the tips of cisternae. The knockdown of either TMF or Rab6 by RNA interference blocked retrograde transport of endocytosed Shiga toxin from early/recycling endosomes to the trans-Golgi network, causing missorting of the toxin to late endosomes/lysosomes. However, the TMF knockdown caused Rab6-dependent displacement of N-acetylgalactosaminyltransferase-2 (GalNAc-T2), but not beta1,4-galactosyltransferase (GalT), from the Golgi. Analyses using chimeric proteins, in which the cytoplasmic regions of GalNAc-T2 and GalT were exchanged, revealed that the cytoplasmic region of GalNAc-T2 plays a crucial role in its TMF-dependent Golgi retention. These observations suggest critical roles for TMF in two Rab6-dependent retrograde transport processes: one from endosomes to the Golgi and the other from the Golgi to the ER.
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Affiliation(s)
- Junko Yamane
- Department of Cell Biology, Faculty of Medicine, Kyoto University, Kyoto, Japan
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20
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Jollivet F, Raposo G, Dimitrov A, Sougrat R, Goud B, Perez F. Analysis of de novo Golgi complex formation after enzyme-based inactivation. Mol Biol Cell 2007; 18:4637-47. [PMID: 17855505 PMCID: PMC2043539 DOI: 10.1091/mbc.e07-08-0799] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The Golgi complex is characterized by its unique morphology of closely apposed flattened cisternae that persists despite the large quantity of lipids and proteins that transit bidirectionally. Whether such a structure is maintained through endoplasmic reticulum (ER)-based recycling and auto-organization or whether it depends on a permanent Golgi structure is strongly debated. To further study Golgi maintenance in interphase cells, we developed a method allowing for a drug-free inactivation of Golgi dynamics and function in living cells. After Golgi inactivation, a new Golgi-like structure, containing only certain Golgi markers and newly synthesized cargoes, was produced. However, this structure did not acquire a normal Golgi architecture and was unable to ensure a normal trafficking activity. This suggests an integrative model for Golgi maintenance in interphase where the ER is able to autonomously produce Golgi-like structures that need pre-existing Golgi complexes to be organized as morphologically normal and active Golgi elements.
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Affiliation(s)
- Florence Jollivet
- *Centre National de la Recherche Scientifique Unité Mixte de Recherche 144, 75248 Paris Cedex 05, France
- Institut Curie, 75248 Paris Cedex 05, France; and
| | - Graça Raposo
- *Centre National de la Recherche Scientifique Unité Mixte de Recherche 144, 75248 Paris Cedex 05, France
- Institut Curie, 75248 Paris Cedex 05, France; and
| | - Ariane Dimitrov
- *Centre National de la Recherche Scientifique Unité Mixte de Recherche 144, 75248 Paris Cedex 05, France
- Institut Curie, 75248 Paris Cedex 05, France; and
| | - Rachid Sougrat
- Cell Biology and Metabolism Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-5430
| | - Bruno Goud
- *Centre National de la Recherche Scientifique Unité Mixte de Recherche 144, 75248 Paris Cedex 05, France
- Institut Curie, 75248 Paris Cedex 05, France; and
| | - Franck Perez
- *Centre National de la Recherche Scientifique Unité Mixte de Recherche 144, 75248 Paris Cedex 05, France
- Institut Curie, 75248 Paris Cedex 05, France; and
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21
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Wessels E, Simpson JC. Impact of live cell imaging on coated vesicle research. Semin Cell Dev Biol 2007; 18:412-23. [PMID: 17689276 DOI: 10.1016/j.semcdb.2007.07.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2007] [Revised: 06/29/2007] [Accepted: 07/02/2007] [Indexed: 11/21/2022]
Abstract
The role of membrane traffic is to transfer cargo between distinct subcellular compartments. Each individual trafficking event involves the creation, transport and fusion of vesicular and tubular carriers that are formed and regulated via cytoplasmic coat protein complexes. The dynamic nature of this process is therefore highly suitable for studying using live cell imaging techniques. Although these approaches have raised further questions for the field, they have also been instrumental in providing essential new information, in particular relating to the morphology of transport carriers and the exchange kinetics of coat proteins and their regulators on membranes. Here, we present an overview of live cell-imaging experiments that have been used in the study of coated-vesicle transport, and provide specific examples of their impact on our understanding of coat function.
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Affiliation(s)
- Els Wessels
- Cell Biology and Biophysics Unit, European Molecular Biology Laboratory (EMBL), Meyerhofstrasse 1, 69117 Heidelberg, Germany.
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22
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Sokolova YY, Snigirevskaya ES, Komissarchik YY. The Golgi apparatus in parasitic protists. ACTA ACUST UNITED AC 2007. [DOI: 10.1134/s1990519x07040037] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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23
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Efimov A, Kharitonov A, Efimova N, Loncarek J, Miller PM, Andreyeva N, Gleeson P, Galjart N, Maia ARR, McLeod IX, Yates JR, Maiato H, Khodjakov A, Akhmanova A, Kaverina I. Asymmetric CLASP-dependent nucleation of noncentrosomal microtubules at the trans-Golgi network. Dev Cell 2007; 12:917-30. [PMID: 17543864 PMCID: PMC2705290 DOI: 10.1016/j.devcel.2007.04.002] [Citation(s) in RCA: 383] [Impact Index Per Article: 22.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2006] [Revised: 03/05/2007] [Accepted: 04/05/2007] [Indexed: 10/23/2022]
Abstract
Proper organization of microtubule arrays is essential for intracellular trafficking and cell motility. It is generally assumed that most if not all microtubules in vertebrate somatic cells are formed by the centrosome. Here we demonstrate that a large number of microtubules in untreated human cells originate from the Golgi apparatus in a centrosome-independent manner. Both centrosomal and Golgi-emanating microtubules need gamma-tubulin for nucleation. Additionally, formation of microtubules at the Golgi requires CLASPs, microtubule-binding proteins that selectively coat noncentrosomal microtubule seeds. We show that CLASPs are recruited to the trans-Golgi network (TGN) at the Golgi periphery by the TGN protein GCC185. In sharp contrast to radial centrosomal arrays, microtubules nucleated at the peripheral Golgi compartment are preferentially oriented toward the leading edge in motile cells. We propose that Golgi-emanating microtubules contribute to the asymmetric microtubule networks in polarized cells and support diverse processes including post-Golgi transport to the cell front.
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Affiliation(s)
- Andrey Efimov
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232-8240, USA
| | | | - Nadia Efimova
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232-8240, USA
| | - Jadranka Loncarek
- Wadsworth Center, New York State Department of Health, Albany, NY 12201-0509, USA
| | - Paul M. Miller
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232-8240, USA
| | | | - Paul Gleeson
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Vic 3010, Australia
| | - Niels Galjart
- Department of Cell Biology and Genetics, Erasmus MC, 3000 DR Rotterdam, The Netherlands
| | - Ana R. R. Maia
- Institute for Molecular Cell Biology & Laboratory of Molecular and Cell Biology, Faculdade de Medicine, University Porto, 4050-345 Porto, Portugal
| | - Ian X. McLeod
- Department of Cell Biology, Scripps Research Institute, La Jolla, CA 93037, USA
| | - John R. Yates
- Department of Cell Biology, Scripps Research Institute, La Jolla, CA 93037, USA
| | - Helder Maiato
- Institute for Molecular Cell Biology & Laboratory of Molecular and Cell Biology, Faculdade de Medicine, University Porto, 4050-345 Porto, Portugal
| | - Alexey Khodjakov
- Wadsworth Center, New York State Department of Health, Albany, NY 12201-0509, USA
| | - Anna Akhmanova
- Department of Cell Biology and Genetics, Erasmus MC, 3000 DR Rotterdam, The Netherlands
| | - Irina Kaverina
- Department of Cell and Developmental Biology, Vanderbilt University Medical Center, Nashville, TN 37232-8240, USA
- corresponding author, ; phone: (615)-936 5567; fax: (615)-936 5673
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24
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Beznoussenko GV, Dolgikh VV, Seliverstova EV, Semenov PB, Tokarev YS, Trucco A, Micaroni M, Di Giandomenico D, Auinger P, Senderskiy IV, Skarlato SO, Snigirevskaya ES, Komissarchik YY, Pavelka M, De Matteis MA, Luini A, Sokolova YY, Mironov AA. Analogs of the Golgi complex in microsporidia: structure and avesicular mechanisms of function. J Cell Sci 2007; 120:1288-98. [PMID: 17356068 DOI: 10.1242/jcs.03402] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Microsporidia are obligatory intracellular parasites, most species of which live in the host cell cytosol. They synthesize and then transport secretory proteins from the endoplasmic reticulum to the plasma membrane for formation of the spore wall and the polar tube for cell invasion. However, microsporidia do not have a typical Golgi complex. Here, using quick-freezing cryosubstitution and chemical fixation, we demonstrate that the Golgi analogs of the microsporidia Paranosema (Antonospora) grylli and Paranosema locustae appear as 300-nm networks of thin (25- to 40-nm diameter), branching or varicose tubules that display histochemical features of a Golgi, but that do not have vesicles. Vesicles are not formed even if membrane fusion is inhibited. These tubular networks are connected to the endoplasmic reticulum, the plasma membrane and the forming polar tube, and are positive for Sec13, gammaCOP and analogs of giantin and GM130. The spore-wall and polar-tube proteins are transported from the endoplasmic reticulum to the target membranes through these tubular networks, within which they undergo concentration and glycosylation. We suggest that the intracellular transport of secreted proteins in microsporidia occurs by a progression mechanism that does not involve the participation of vesicles generated by coat proteins I and II.
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Affiliation(s)
- Galina V Beznoussenko
- Department of Cell Biology and Oncology, Consorzio Mario Negri Sud, Via Nazionale, 66030 Santa Maria Imbaro (Chieti), Italy
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25
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Dejgaard SY, Murshid A, Dee KM, Presley JF. Confocal microscopy-based linescan methodologies for intra-Golgi localization of proteins. J Histochem Cytochem 2007; 55:709-19. [PMID: 17341478 DOI: 10.1369/jhc.6a7090.2007] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Localization of resident Golgi proteins to earlier (cis) or later (trans) Golgi compartments has traditionally required quantitative immunocytochemistry and electron microscopy, which are inaccessible to many researchers. For this reason, light microscopy has often been used, initially for localization of Golgi glycotransferases and, more recently, for other Golgi proteins (e.g., Arf1, GBF1, Rab6). Quantitation of light microscopic intra-Golgi localization can be problematic. We describe here a novel quantitative light microscopic methodology using linescans crossing the Golgi ribbon. Our method determines a localization for the unknown protein in a one-dimensional coordinate system in which 0.0 corresponds to localization of a cis marker and 1.0 to localization of a trans marker. We also describe a variant of this methodology in which Golgi morphology is simplified by nocodazole-induced dispersal into ministacks, allowing a fully automated analysis. In our assay, beta1,4-galactosyltransferase-YFP and Golgin97 localize similarly to trans markers, whereas p115, GBF1, and p58-YFP are similarly near other cis markers. The medial Golgi protein alpha1,3-1,6-mannosidase II gives an intermediate localization in this assay. These methodologies may prove useful in instances where electron microscopy is technically difficult as well as when rapid analysis of large numbers of samples is required.
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Affiliation(s)
- Selma Yilmaz Dejgaard
- Department of Anatomy & Cell Biology, 1/28 Strathcona Bldg., 3640 University, McGill University, Montreal, QC H3A 2B2
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26
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Mironov AA, Banin VV, Sesorova IS, Dolgikh VV, Luini A, Beznoussenko GV. Evolution of the Endoplasmic Reticulum and the Golgi Complex. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2007; 607:61-72. [DOI: 10.1007/978-0-387-74021-8_5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/21/2023]
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27
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Béthune J, Wieland F, Moelleken J. COPI-mediated Transport. J Membr Biol 2006; 211:65-79. [PMID: 17041781 DOI: 10.1007/s00232-006-0859-7] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2005] [Revised: 03/18/2006] [Indexed: 12/27/2022]
Abstract
COPI-coated vesicles are protein and liquid carriers that mediate transport within the early secretory pathway. In this Topical Review, we present their main protein components and discuss current models for cargo sorting. Finally, we describe the striking similarities that exist between the COPI system and the two other characterized types of vesicular carriers: COPII- and clathrin-coated vesicles.
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Affiliation(s)
- J Béthune
- Biochemie Zentrum, University of Heidelberg, Im Neuenheimer Feld 328, D-69120, Heidelberg, Germany.
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28
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Domanov YA, Kinnunen PKJ. Antimicrobial peptides temporins B and L induce formation of tubular lipid protrusions from supported phospholipid bilayers. Biophys J 2006; 91:4427-39. [PMID: 16997872 PMCID: PMC1779916 DOI: 10.1529/biophysj.106.091702] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
The binding of the antimicrobial peptides temporins B and L to supported lipid bilayer (SLB) model membranes composed of phosphatidylcholine and phosphatidylglycerol (4:1, mol/mol) caused the formation of fibrillar protrusions, visible by fluorescent microscopy of both a fluorescent lipid analog and a labeled peptide. Multicolor imaging at low peptide-to-lipid ratios (P/L < approximately 1:5) revealed an initial in-plane segregation of membrane-bound peptide and partial exclusion of lipid from the peptide-enriched areas. Subsequently, at higher P/L numerous flexible lipid fibrils were seen growing from the areas enriched in lipid. The fibrils have diameters <250 nm and lengths of up to approximately 1 mm. Fibril formation reduces the in-plane heterogeneity and results in a relatively even redistribution of bound peptide over the planar bilayer and the fibrils. Physical properties of the lipid fibrils suggest that they have a tubular structure. Our data demonstrate that the peptide-lipid interactions alone can provide a driving force for the spontaneous membrane shape transformations leading to tubule outgrowth and elongation. Further experiments revealed the importance of positive curvature strain in the tubulation process as well as the sufficient positive charge on the peptide (>/=+2). The observed membrane transformations could provide a simplified in vitro model for morphogenesis of intracellular tubular structures and intercellular connections.
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Affiliation(s)
- Yegor A Domanov
- Helsinki Biophysics & Biomembrane Group, Medical Biochemistry/Institute of Biomedicine, University of Helsinki, Helsinki, Finland
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