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Manzer KM, Fromme JC. The Arf-GAP Age2 localizes to the late-Golgi via a conserved amphipathic helix. Mol Biol Cell 2023; 34:ar119. [PMID: 37672345 PMCID: PMC10846627 DOI: 10.1091/mbc.e23-07-0283] [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: 07/24/2023] [Revised: 08/29/2023] [Accepted: 08/29/2023] [Indexed: 09/08/2023] Open
Abstract
Arf GTPases are central regulators of the Golgi complex, which serves as the nexus of membrane-trafficking pathways in eukaryotic cells. Arf proteins recruit dozens of effectors to modify membranes, sort cargos, and create and tether transport vesicles, and are therefore essential for orchestrating Golgi trafficking. The regulation of Arf activity is controlled by the action of Arf-GEFs which activate via nucleotide exchange, and Arf-GAPs which inactivate via nucleotide hydrolysis. The localization dynamics of Arf GTPases and their Arf-GAPs during Golgi maturation have not been reported. Here we use the budding yeast model to examine the temporal localization of the Golgi Arf-GAPs. We also determine the mechanisms used by the Arf-GAP Age2 to localize to the Golgi. We find that the catalytic activity of Age2 and a conserved sequence in the unstructured C-terminal domain of Age2 are both required for Golgi localization. This sequence is predicted to form an amphipathic helix and mediates direct binding of Age2 to membranes in vitro. We also report the development of a probe for sensing active Arf1 in living cells and use this probe to characterize the temporal dynamics of Arf1 during Golgi maturation.
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Affiliation(s)
- Kaitlyn M. Manzer
- Department of Molecular Biology & Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14850
| | - J. Christopher Fromme
- Department of Molecular Biology & Genetics, Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14850
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2
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Manzer KM, Fromme JC. The Arf-GAP Age2 localizes to the late-Golgi via a conserved amphipathic helix. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.23.550229. [PMID: 37546741 PMCID: PMC10402032 DOI: 10.1101/2023.07.23.550229] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
Arf GTPases are central regulators of the Golgi complex, which serves as the nexus of membrane trafficking pathways in eukaryotic cells. Arf proteins recruit dozens of effectors to modify membranes, sort cargos, and create and tether transport vesicles, and are therefore essential for orchestrating Golgi trafficking. The regulation of Arf activity is controlled by the action of Arf-GEFs, which activate via nucleotide exchange, and Arf-GAPs, which inactivate via nucleotide hydrolysis. The localization dynamics of Arf GTPases and their Arf-GAPs during Golgi maturation have not been reported. Here we use the budding yeast model to examine the temporal localization of the Golgi Arf-GAPs. We also determine the mechanisms used by the Arf-GAP Age2 to localize to the Golgi. We find that the catalytic activity of Age2 and a conserved sequence in the unstructured C-terminal domain of Age2 are both required for Golgi localization. This sequence is predicted to form an amphipathic helix and mediates direct binding of Age2 to membranes in vitro . We also report the development of a probe for sensing active Arf1 in living cells and use this probe to characterize the temporal dynamics of Arf1 during Golgi maturation.
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Affiliation(s)
- Kaitlyn M Manzer
- Department of Molecular Biology & Genetics and Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14850 USA
| | - J Christopher Fromme
- Department of Molecular Biology & Genetics and Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14850 USA
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3
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Wong-Dilworth L, Rodilla-Ramirez C, Fox E, Restel SD, Stockhammer A, Adarska P, Bottanelli F. STED imaging of endogenously tagged ARF GTPases reveals their distinct nanoscale localizations. J Cell Biol 2023; 222:e202205107. [PMID: 37102998 PMCID: PMC10140647 DOI: 10.1083/jcb.202205107] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 01/10/2023] [Accepted: 04/05/2023] [Indexed: 04/28/2023] Open
Abstract
ADP-ribosylation factor (ARF) GTPases are major regulators of cellular membrane homeostasis. High sequence similarity and multiple, possibly redundant functions of the five human ARFs make investigating their function a challenging task. To shed light on the roles of the different Golgi-localized ARF members in membrane trafficking, we generated CRISPR-Cas9 knockins (KIs) of type I (ARF1 and ARF3) and type II ARFs (ARF4 and ARF5) and mapped their nanoscale localization with stimulated emission depletion (STED) super-resolution microscopy. We find ARF1, ARF4, and ARF5 on segregated nanodomains on the cis-Golgi and ER-Golgi intermediate compartments (ERGIC), revealing distinct roles in COPI recruitment on early secretory membranes. Interestingly, ARF4 and ARF5 define Golgi-tethered ERGIC elements decorated by COPI and devoid of ARF1. Differential localization of ARF1 and ARF4 on peripheral ERGICs suggests the presence of functionally different classes of intermediate compartments that could regulate bi-directional transport between the ER and the Golgi. Furthermore, ARF1 and ARF3 localize to segregated nanodomains on the trans-Golgi network (TGN) and are found on TGN-derived post-Golgi tubules, strengthening the idea of distinct roles in post-Golgi sorting. This work provides the first map of the nanoscale organization of human ARF GTPases on cellular membranes and sets the stage to dissect their numerous cellular roles.
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Affiliation(s)
| | | | - Eleanor Fox
- Institut für Biochemie, Freie Universität Berlin, Berlin, Germany
| | | | | | - Petia Adarska
- Institut für Biochemie, Freie Universität Berlin, Berlin, Germany
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4
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Ben Ahmed A, Lemaire Q, Scache J, Mariller C, Lefebvre T, Vercoutter-Edouart AS. O-GlcNAc Dynamics: The Sweet Side of Protein Trafficking Regulation in Mammalian Cells. Cells 2023; 12:1396. [PMID: 37408229 PMCID: PMC10216988 DOI: 10.3390/cells12101396] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 05/11/2023] [Accepted: 05/12/2023] [Indexed: 07/07/2023] Open
Abstract
The transport of proteins between the different cellular compartments and the cell surface is governed by the secretory pathway. Alternatively, unconventional secretion pathways have been described in mammalian cells, especially through multivesicular bodies and exosomes. These highly sophisticated biological processes rely on a wide variety of signaling and regulatory proteins that act sequentially and in a well-orchestrated manner to ensure the proper delivery of cargoes to their final destination. By modifying numerous proteins involved in the regulation of vesicular trafficking, post-translational modifications (PTMs) participate in the tight regulation of cargo transport in response to extracellular stimuli such as nutrient availability and stress. Among the PTMs, O-GlcNAcylation is the reversible addition of a single N-acetylglucosamine monosaccharide (GlcNAc) on serine or threonine residues of cytosolic, nuclear, and mitochondrial proteins. O-GlcNAc cycling is mediated by a single couple of enzymes: the O-GlcNAc transferase (OGT) which catalyzes the addition of O-GlcNAc onto proteins, and the O-GlcNAcase (OGA) which hydrolyses it. Here, we review the current knowledge on the emerging role of O-GlcNAc modification in the regulation of protein trafficking in mammalian cells, in classical and unconventional secretory pathways.
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5
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Li S, Wang Z, Chen M, Xiao Y, Min J, Hu M, Tang J, Hong L. ArfGAP3 regulates vesicle transport and glucose uptake in myoblasts. Cell Signal 2023; 103:110551. [PMID: 36476390 DOI: 10.1016/j.cellsig.2022.110551] [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: 07/03/2022] [Revised: 11/19/2022] [Accepted: 11/30/2022] [Indexed: 12/12/2022]
Abstract
Skeletal muscle injuries are common, and damaged myofibers are repaired through proliferation and differentiation of muscle satellite cells. GLUT4 is enriched in GLUT4 storage vesicles (GSVs) and plays a crucial role in the maintenance of muscle function. ArfGAP3 regulates the vesicle transport especially for COPI coat assembly, but its effects on GSVs and the repair process after skeletal muscle injury remains unclear. In this study, datasets related to skeletal muscle injury and myoblast differentiation GSE469, GSE5413, GSE45577 and GSE108040 were retrieved through the GEO database and the expression of heptameric coat protein complex I (COPI) and Golgi vesicle transport-related genes in various datasets, as well as the expression correlation between ArfGAP2, ArfGAP3 and COPI-related genes COPA, COPB1, COPB2, COPE, COPZ1, COPZ2 were analyzed. The results suggested that ArfGAP3 was expressed in the process of repair after skeletal muscle injury and myoblast differentiation and that ArfGAP3 was positively correlated with COPI-related genes. In vitro experimental results showed that ArfGAP3 was colocalized with COPA, COPB, COPG protein, and GLUT4 in C2C12 myoblasts. After the downregulation of ArfGAP3 expression, intracellular vesicle transport, and glucose uptake were blocked, the proliferation of myoblasts under low glucose culture conditions was impaired, the proportion of apoptosis increased, and myotube differentiation was impaired. In summary, ArfGAP3 regulates COPI-associated vesicle and GSVs transport and affects the proliferation and differentiation ability of myoblasts by influencing glucose uptake, thereby modulating the repair process after skeletal muscle injury.
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Affiliation(s)
- Suting Li
- Department of Gynecology and Obstetrics, Renmin Hospital of Wuhan University, Wuhan, Hubei Province, People's Republic of China
| | - Zhi Wang
- Department of Gynecology and Obstetrics, Renmin Hospital of Wuhan University, Wuhan, Hubei Province, People's Republic of China
| | - Mao Chen
- Department of Gynecology and Obstetrics, Renmin Hospital of Wuhan University, Wuhan, Hubei Province, People's Republic of China
| | - Ya Xiao
- Department of Gynecology and Obstetrics, Renmin Hospital of Wuhan University, Wuhan, Hubei Province, People's Republic of China
| | - Jie Min
- Department of Gynecology and Obstetrics, Renmin Hospital of Wuhan University, Wuhan, Hubei Province, People's Republic of China
| | - Ming Hu
- Department of Gynecology and Obstetrics, Renmin Hospital of Wuhan University, Wuhan, Hubei Province, People's Republic of China
| | - Jianming Tang
- Department of Gynecology and Obstetrics, Renmin Hospital of Wuhan University, Wuhan, Hubei Province, People's Republic of China
| | - Li Hong
- Department of Gynecology and Obstetrics, Renmin Hospital of Wuhan University, Wuhan, Hubei Province, People's Republic of China.
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6
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Taylor RJ, Tagiltsev G, Briggs JAG. The structure of COPI vesicles and regulation of vesicle turnover. FEBS Lett 2023; 597:819-835. [PMID: 36513395 DOI: 10.1002/1873-3468.14560] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 11/30/2022] [Accepted: 12/02/2022] [Indexed: 12/15/2022]
Abstract
COPI-coated vesicles mediate transport between Golgi stacks and retrograde transport from the Golgi to the endoplasmic reticulum. The COPI coat exists as a stable heptameric complex in the cytosol termed coatomer and is recruited en bloc to the membrane for vesicle formation. Recruitment of COPI onto membranes is mediated by the Arf family of small GTPases, which, in their GTP-bound state, bind both membrane and coatomer. Arf GTPases also influence cargo selection, vesicle scission and vesicle uncoating. Guanine nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs) regulate nucleotide binding by Arf GTPases. To understand the mechanism of COPI-coated vesicle trafficking, it is necessary to characterize the interplay between coatomer and Arf GTPases and their effectors. It is also necessary to understand interactions between coatomer and cargo, cargo adaptors/receptors and tethers facilitating binding to the target membrane. Here, we summarize current knowledge of COPI coat protein structure; we describe how structural and biochemical studies contributed to this knowledge; we review mechanistic insights into COPI vesicle biogenesis and disassembly; and we discuss the potential to answer open questions in the field.
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Affiliation(s)
- Rebecca J Taylor
- Department of Cell and Virus Structure, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Grigory Tagiltsev
- Department of Cell and Virus Structure, Max Planck Institute of Biochemistry, Martinsried, Germany
| | - John A G Briggs
- Department of Cell and Virus Structure, Max Planck Institute of Biochemistry, Martinsried, Germany
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7
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Yue X, Qian Y, Zhu L, Gim B, Bao M, Jia J, Jing S, Wang Y, Tan C, Bottanelli F, Ziltener P, Choi S, Hao P, Lee I. ACBD3 modulates KDEL receptor interaction with PKA for its trafficking via tubulovesicular carrier. BMC Biol 2021; 19:194. [PMID: 34493279 PMCID: PMC8424950 DOI: 10.1186/s12915-021-01137-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Accepted: 08/30/2021] [Indexed: 11/10/2022] Open
Abstract
Background KDEL receptor helps establish cellular equilibrium in the early secretory pathway by recycling leaked ER-chaperones to the ER during secretion of newly synthesized proteins. Studies have also shown that KDEL receptor may function as a signaling protein that orchestrates membrane flux through the secretory pathway. We have recently shown that KDEL receptor is also a cell surface receptor, which undergoes highly complex itinerary between trans-Golgi network and the plasma membranes via clathrin-mediated transport carriers. Ironically, however, it is still largely unknown how KDEL receptor is distributed to the Golgi at steady state, since its initial discovery in late 1980s. Results We used a proximity-based in vivo tagging strategy to further dissect mechanisms of KDEL receptor trafficking. Our new results reveal that ACBD3 may be a key protein that regulates KDEL receptor trafficking via modulation of Arf1-dependent tubule formation. We demonstrate that ACBD3 directly interact with KDEL receptor and form a functionally distinct protein complex in ArfGAPs-independent manner. Depletion of ACBD3 results in re-localization of KDEL receptor to the ER by inducing accelerated retrograde trafficking of KDEL receptor. Importantly, this is caused by specifically altering KDEL receptor interaction with Protein Kinase A and Arf1/ArfGAP1, eventually leading to increased Arf1-GTP-dependent tubular carrier formation at the Golgi. Conclusions These results suggest that ACBD3 may function as a negative regulator of PKA activity on KDEL receptor, thereby restricting its retrograde trafficking in the absence of KDEL ligand binding. Since ACBD3 was originally identified as PAP7, a PBR/PKA-interacting protein at the Golgi/mitochondria, we propose that Golgi-localization of KDEL receptor is likely to be controlled by its interaction with ACBD3/PKA complex at steady state, providing a novel insight for establishment of cellular homeostasis in the early secretory pathway. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-021-01137-7.
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Affiliation(s)
- Xihua Yue
- School of Life Science and Technology, ShanghaiTech University, Pudong, Shanghai, China
| | - Yi Qian
- School of Life Science and Technology, ShanghaiTech University, Pudong, Shanghai, China
| | - Lianhui Zhu
- School of Life Science and Technology, ShanghaiTech University, Pudong, Shanghai, China
| | - Bopil Gim
- School of Physical Science and Technology, ShanghaiTech University, Pudong, Shanghai, China
| | - Mengjing Bao
- School of Life Science and Technology, ShanghaiTech University, Pudong, Shanghai, China
| | - Jie Jia
- School of Life Science and Technology, ShanghaiTech University, Pudong, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Shuaiyang Jing
- School of Life Science and Technology, ShanghaiTech University, Pudong, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Yijing Wang
- School of Life Science and Technology, ShanghaiTech University, Pudong, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Chuanting Tan
- School of Life Science and Technology, ShanghaiTech University, Pudong, Shanghai, China.,University of Chinese Academy of Sciences, Beijing, China
| | - Francesca Bottanelli
- Institut für Biochemie, Freie Universität Berlin, Thielallee 63, 14195, Berlin, Germany
| | - Pascal Ziltener
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT, USA
| | - Sunkyu Choi
- Proteomics Core, Weill Cornell Medicine-Qatar, Doha, Qatar
| | - Piliang Hao
- School of Life Science and Technology, ShanghaiTech University, Pudong, Shanghai, China
| | - Intaek Lee
- School of Life Science and Technology, ShanghaiTech University, Pudong, Shanghai, China. .,Shanghai Institute for Advanced Immunochemical Studies, Shanghai, China.
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8
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Luo C, Peng W, Kang J, Chen C, Peng J, Wang Y, Tang Q, Xie H, Li Y, Pan X. Glutamine Regulates Cell Growth and Casein Synthesis through the CYTHs/ARFGAP1-Arf1-mTORC1 Pathway in Bovine Mammary Epithelial Cells. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2021; 69:6810-6819. [PMID: 34096300 DOI: 10.1021/acs.jafc.1c02223] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
In the dairy industry, glutamine (Gln) is often used as a feed additive to increase milk yield and quality; however, the molecular regulation underneath needs further clarification. Here, with bovine mammary epithelial cells (BMECs), the effects and mechanisms of Gln on cell growth and casein synthesis were assessed. When Gln was added or depleted from BMECs, both cell growth and β-casein (CSN2) expression were increased or decreased, respectively. Overexpressing or inhibiting the mechanistic target of rapamycin (mTOR) revealed that Gln regulated cell growth and CSN2 synthesis through the mTORC1 pathway. A similar intervention of ADP-ribosylation factor 1 (Arf1) uncovered that Gln activated the mTORC1 pathway through Arf1. We next observed that both guanine nucleotide exchange factors, Cytohesin-1/2/3 (CYTH1/2/3, CYTHs) and ADP-ribosylation factor GTPase activating protein 1 (ARFGAP1), interacted with Arf1. Inhibiting CYTHs or ARFGAP1 showed that Gln supplement or depletion activated or inactivated Arf1 through CYTHs or ARFGAP1, respectively. Collectively, this study demonstrated that Gln positively regulated cell growth and casein synthesis in BMECs, which works through the CYTHs/ARFGAP1-Arf1-mTORC1 pathway. These results greatly enhanced current understanding regarding the regulation of the mTOR pathway and provided new insights for the processes of cell growth and casein synthesis by amino acids, particularly Gln.
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9
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Pipaliya SV, Thompson LA, Dacks JB. The reduced ARF regulatory system in Giardia intestinalis pre-dates the transition to parasitism in the lineage Fornicata. Int J Parasitol 2021; 51:825-839. [PMID: 33848497 DOI: 10.1016/j.ijpara.2021.02.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 02/01/2021] [Accepted: 02/02/2021] [Indexed: 12/18/2022]
Abstract
Giardia intestinalis is an enteric pathogen with an extremely modified membrane trafficking system, lacking canonical compartments such as the Golgi, endosomes, and intermediate vesicle carriers. By comparison the fornicate relatives of Giardia possess greater endomembrane system complexity. In eukaryotes, the ADP ribosylation factor (ARF) GTPase regulatory system proteins, which consist of the small GTPase ARF1, and its guanine exchange nucleotide factors (GEFs) and GTPase activating proteins (GAPs), coordinate temporal and directional trafficking of cargo vesicles by recognizing and interacting with heterotetrameric coat complexes at pre-Golgi and post-Golgi interfaces. To understand the evolution of this regulatory system across the fornicate lineage, we have performed comparative genomic and phylogenetic analyses of the ARF GTPases, and their regulatory GAPs and GEFs in fornicate genomes and transcriptomes. Prior to our analysis of the fornicates, we first establish that the ARF GAP sub-family ArfGAP with dual PH domains (ADAP) is sparsely distributed but present in at least four eukaryotic supergroups and thus was likely present in the Last Eukaryotic Common Ancestor (LECA). Next, our collective comparative genomic and phylogenetic investigations into the ARF regulatory proteins in fornicates identify a duplication of ARF1 GTPase yielding two paralogues of ARF1F proteins, ancestral to all fornicates and present in all examined isolates of Giardia. However, the ARF GEF and ARF GAP complement is reduced compared with the LECA. This investigation shows that the system was significantly streamlined prior to the fornicate ancestor but was not further reduced concurrent with a transition into a parasitic lifestyle.
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Affiliation(s)
- Shweta V Pipaliya
- Division of Infectious Diseases, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada.
| | - L Alexa Thompson
- Division of Infectious Diseases, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada; Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Canada
| | - Joel B Dacks
- Division of Infectious Diseases, Department of Medicine, University of Alberta, Edmonton, Alberta, Canada; Institute of Parasitology Biology Centre, CAS v.v.i. Branisovska 31, 370 05 Ceske Budejovice, Czech Republic.
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10
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Feng H, Cheng H, Hsiao T, Lin T, Hsu J, Huang L, Yu C. ArfGAP1 acts as a GTPase‐activating protein for human ADP‐ribosylation factor‐like 1 protein. FASEB J 2021; 35:e21337. [DOI: 10.1096/fj.202000818rr] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2020] [Revised: 12/13/2020] [Accepted: 12/17/2020] [Indexed: 01/08/2023]
Affiliation(s)
- Hsiang‐Pu Feng
- Graduate Institute of Biomedical Sciences, College of Medicine Chang Gung University Taoyuan Taiwan
| | - Hsiao‐Yun Cheng
- Department of Cell and Molecular Biology, College of Medicine Chang Gung University Taoyuan Taiwan
| | - Ting‐Feng Hsiao
- Graduate Institute of Biomedical Sciences, College of Medicine Chang Gung University Taoyuan Taiwan
| | - Tai‐Wei Lin
- Graduate Institute of Biomedical Sciences, College of Medicine Chang Gung University Taoyuan Taiwan
| | - Jia‐Wei Hsu
- Institute of Molecular Medicine, College of Medicine National Taiwan University Taipei Taiwan
- Institute of Biochemical Sciences, College of Life Science National Taiwan University Taipei Taiwan
| | - Lien‐Hung Huang
- Graduate Institute of Biomedical Sciences, College of Medicine Chang Gung University Taoyuan Taiwan
- Department of Neurosurgery Kaohsiung Chang Gung Memorial Hospital Kaohsiung Taiwan
| | - Chia‐Jung Yu
- Graduate Institute of Biomedical Sciences, College of Medicine Chang Gung University Taoyuan Taiwan
- Department of Cell and Molecular Biology, College of Medicine Chang Gung University Taoyuan Taiwan
- Department of Thoracic Medicine Chang Gung Memorial Hospital Taoyuan Taiwan
- Molecular Medicine Research Center Chang Gung University Taoyuan Taiwan
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11
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Arakel EC, Huranova M, Estrada AF, Rau EM, Spang A, Schwappach B. Dissection of GTPase-activating proteins reveals functional asymmetry in the COPI coat of budding yeast. J Cell Sci 2019; 132:jcs.232124. [PMID: 31331965 PMCID: PMC6737914 DOI: 10.1242/jcs.232124] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Accepted: 07/12/2019] [Indexed: 12/11/2022] Open
Abstract
The Arf GTPase controls formation of the COPI vesicle coat. Recent structural models of COPI revealed the positioning of two Arf1 molecules in contrasting molecular environments. Each of these pockets for Arf1 is expected to also accommodate an Arf GTPase-activating protein (ArfGAP). Structural evidence and protein interactions observed between isolated domains indirectly suggest that each niche preferentially recruits one of the two ArfGAPs known to affect COPI, i.e. Gcs1/ArfGAP1 and Glo3/ArfGAP2/3, although only partial structures are available. The functional role of the unique non-catalytic domain of either ArfGAP has not been integrated into the current COPI structural model. Here, we delineate key differences in the consequences of triggering GTP hydrolysis through the activity of one versus the other ArfGAP. We demonstrate that Glo3/ArfGAP2/3 specifically triggers Arf1 GTP hydrolysis impinging on the stability of the COPI coat. We show that the Snf1 kinase complex, the yeast homologue of AMP-activated protein kinase (AMPK), phosphorylates the region of Glo3 that is crucial for this effect and, thereby, regulates its function in the COPI-vesicle cycle. Our results revise the model of ArfGAP function in the molecular context of COPI. This article has an associated First Person interview with the first author of the paper. Highlighted Article: The regulatory domain of the COPI-associated ArfGAP Glo3 can stabilize the COPI coat. GTP hydrolysis is necessary to resolve the stabilised state. This mechanism is regulated by phosphorylation.
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Affiliation(s)
- Eric C Arakel
- Department of Molecular Biology, Universitätsmedizin Göttingen, Humboldtallee 23, 37073 Göttingen, Germany
| | - Martina Huranova
- Growth and Development, Biozentrum, University of Basel, Klingelbergstrasse 50/70, 4056 Basel, Switzerland.,Laboratory of Adaptive Immunity, Institute of Molecular Genetics of the Czech Academy of Sciences, Videnska 1083, 142 20 Prague 4, Czech Republic
| | - Alejandro F Estrada
- Growth and Development, Biozentrum, University of Basel, Klingelbergstrasse 50/70, 4056 Basel, Switzerland
| | - E-Ming Rau
- Growth and Development, Biozentrum, University of Basel, Klingelbergstrasse 50/70, 4056 Basel, Switzerland
| | - Anne Spang
- Growth and Development, Biozentrum, University of Basel, Klingelbergstrasse 50/70, 4056 Basel, Switzerland
| | - Blanche Schwappach
- Department of Molecular Biology, Universitätsmedizin Göttingen, Humboldtallee 23, 37073 Göttingen, Germany .,Max-Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
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12
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Sztul E, Chen PW, Casanova JE, Cherfils J, Dacks JB, Lambright DG, Lee FJS, Randazzo PA, Santy LC, Schürmann A, Wilhelmi I, Yohe ME, Kahn RA. ARF GTPases and their GEFs and GAPs: concepts and challenges. Mol Biol Cell 2019; 30:1249-1271. [PMID: 31084567 PMCID: PMC6724607 DOI: 10.1091/mbc.e18-12-0820] [Citation(s) in RCA: 149] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 02/26/2019] [Accepted: 03/11/2019] [Indexed: 12/12/2022] Open
Abstract
Detailed structural, biochemical, cell biological, and genetic studies of any gene/protein are required to develop models of its actions in cells. Studying a protein family in the aggregate yields additional information, as one can include analyses of their coevolution, acquisition or loss of functionalities, structural pliability, and the emergence of shared or variations in molecular mechanisms. An even richer understanding of cell biology can be achieved through evaluating functionally linked protein families. In this review, we summarize current knowledge of three protein families: the ARF GTPases, the guanine nucleotide exchange factors (ARF GEFs) that activate them, and the GTPase-activating proteins (ARF GAPs) that have the ability to both propagate and terminate signaling. However, despite decades of scrutiny, our understanding of how these essential proteins function in cells remains fragmentary. We believe that the inherent complexity of ARF signaling and its regulation by GEFs and GAPs will require the concerted effort of many laboratories working together, ideally within a consortium to optimally pool information and resources. The collaborative study of these three functionally connected families (≥70 mammalian genes) will yield transformative insights into regulation of cell signaling.
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Affiliation(s)
- Elizabeth Sztul
- Department of Cell, Developmental and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL 35294
| | - Pei-Wen Chen
- Department of Biology, Williams College, Williamstown, MA 01267
| | - James E. Casanova
- Department of Cell Biology, University of Virginia, Charlottesville, VA 22908
| | - Jacqueline Cherfils
- Laboratoire de Biologie et Pharmacologie Appliquée, CNRS and Ecole Normale Supérieure Paris-Saclay, 94235 Cachan, France
| | - Joel B. Dacks
- Division of Infectious Disease, Department of Medicine, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - David G. Lambright
- Program in Molecular Medicine and Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Amherst, MA 01605
| | - Fang-Jen S. Lee
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan
| | | | - Lorraine C. Santy
- Department of Biochemistry and Molecular Biology, Pennsylvania State University, University Park, PA 16802
| | - Annette Schürmann
- German Institute of Human Nutrition, 85764 Potsdam-Rehbrücke, Germany
| | - Ilka Wilhelmi
- German Institute of Human Nutrition, 85764 Potsdam-Rehbrücke, Germany
| | - Marielle E. Yohe
- Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892
| | - Richard A. Kahn
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322-3050
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13
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Quilty D, Chan CJ, Yurkiw K, Bain A, Babolmorad G, Melançon P. The Arf-GDP-regulated recruitment of GBF1 to Golgi membranes requires domains HDS1 and HDS2 and a Golgi-localized protein receptor. J Cell Sci 2018; 132:jcs.208199. [PMID: 29507113 PMCID: PMC6398479 DOI: 10.1242/jcs.208199] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Accepted: 02/14/2018] [Indexed: 01/02/2023] Open
Abstract
We previously proposed a novel mechanism by which the enzyme Golgi-specific Brefeldin A resistance factor 1 (GBF1) is recruited to the membranes of the cis-Golgi, based on in vivo experiments. Here, we extended our in vivo analysis on the production of regulatory Arf-GDP and observed that ArfGAP2 and ArfGAP3 do not play a role in GBF1 recruitment. We confirm that Arf-GDP localization is critical, as a TGN-localized Arf-GDP mutant protein fails to promote GBF1 recruitment. We also reported the establishment of an in vitro GBF1 recruitment assay that supports the regulation of GBF1 recruitment by Arf-GDP. This in vitro assay yielded further evidence for the requirement of a Golgi-localized protein because heat denaturation or protease treatment of Golgi membranes abrogated GBF1 recruitment. Finally, combined in vivo and in vitro measurements indicated that the recruitment to Golgi membranes via a putative receptor requires only the HDS1 and HDS2 domains in the C-terminal half of GBF1. Summary:In vivo and in vitro experiments demonstrate Arf-GDP regulation of GBF1 recruitment to a heat-labile and protease-sensitive site on Golgi membranes. This recruitment requires the HDS1 and HDS2 domains.
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Affiliation(s)
- Douglas Quilty
- Department of Cell Biology, University of Alberta, Edmonton, AB, Canada T6G 2H7
| | - Calvin J Chan
- Department of Cell Biology, University of Alberta, Edmonton, AB, Canada T6G 2H7
| | - Katherine Yurkiw
- Department of Cell Biology, University of Alberta, Edmonton, AB, Canada T6G 2H7
| | - Alexandra Bain
- Department of Cell Biology, University of Alberta, Edmonton, AB, Canada T6G 2H7
| | - Ghazal Babolmorad
- Department of Cell Biology, University of Alberta, Edmonton, AB, Canada T6G 2H7
| | - Paul Melançon
- Department of Cell Biology, University of Alberta, Edmonton, AB, Canada T6G 2H7
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14
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Abstract
The coat protein complex I (COPI) allows the precise sorting of lipids and proteins between Golgi cisternae and retrieval from the Golgi to the ER. This essential role maintains the identity of the early secretory pathway and impinges on key cellular processes, such as protein quality control. In this Cell Science at a Glance and accompanying poster, we illustrate the different stages of COPI-coated vesicle formation and revisit decades of research in the context of recent advances in the elucidation of COPI coat structure. By calling attention to an array of questions that have remained unresolved, this review attempts to refocus the perspectives of the field.
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Affiliation(s)
- Eric C Arakel
- Department of Molecular Biology, Universitätsmedizin Göttingen, Humboldtallee 23, 37073 Göttingen, Germany
| | - Blanche Schwappach
- Department of Molecular Biology, Universitätsmedizin Göttingen, Humboldtallee 23, 37073 Göttingen, Germany .,Max-Planck Institute for Biophysical Chemistry, 37077 Göttingen, Germany
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15
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Abstract
Advances in imaging techniques have shed new light on the structure of vesicles formed by COPI protein complexes.
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Affiliation(s)
- Eric C Arakel
- Department of Molecular Biology, University Medical Center Göttingen, Göttingen, Germany
| | - Blanche Schwappach
- Department of Molecular Biology, University Medical Center Göttingen, Göttingen, Germany
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16
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Zhang S, Liu X, Li L, Yu R, He J, Zhang H, Zheng X, Wang P, Zhang Z. The ArfGAP protein MoGlo3 regulates the development and pathogenicity of Magnaporthe oryzae. Environ Microbiol 2017; 19:3982-3996. [PMID: 28504350 DOI: 10.1111/1462-2920.13798] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 05/09/2017] [Indexed: 01/21/2023]
Abstract
The ADP ribosylation factor (Arf) and the coat protein complex I (COPI) are involved in vesicle transport. Together with GTPase-activating proteins (ArfGAPs) and guanine exchange factors (ArfGEFs) that regulate the activity of Arf, they govern vesicle formation, COPI trafficking and the maintenance of the Golgi complex. In an ongoing effort to study the role of membrane trafficking in pathogenesis of the rice blast fungus Magnaporthe oryzae, we identified MoGlo3 as an ArfGAP protein that is homologous to Glo3p of the budding yeast Saccharomyces cerevisiae. As suspected, MoGlo3 partially complements the function of yeast Glo3p. Consistent with findings in S. cerevisiae, MoGlo3 is localized to the Golgi, and that the localization is dependent on the conserved BoCCS domain. We found that MoGlo3 is highly expressed during conidiation and early infection stages and is required for vegetative growth, conidial production and sexual development. We further found that the ΔMoglo3 mutant is defective in endocytosis, scavenging of the reactive oxygen species, and in the response to endoplasmic reticulum (ER) stress. The combined effects result in failed appressorium function and decreased pathogenicity. Moreover, we provided evidence showing that the domains including the GAP, BoCCS and GRM are all important for normal MoGlo3 functions. Our studies further illustrate the importance of normal membrane trafficking in the physiology and pathogenicity of the rice blast fungus.
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Affiliation(s)
- Shengpei Zhang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, People's Republic of China
| | - Xiu Liu
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, People's Republic of China
| | - Lianwei Li
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, People's Republic of China
| | - Rui Yu
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, People's Republic of China
| | - Jialiang He
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, People's Republic of China
| | - Haifeng Zhang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, People's Republic of China
| | - Xiaobo Zheng
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, People's Republic of China
| | - Ping Wang
- Departments of Pediatrics and Microbiology, Immunology, and Parasitology, Louisiana State University Health Sciences Center, New Orleans, LA 70112, USA
| | - Zhengguang Zhang
- Department of Plant Pathology, College of Plant Protection, Nanjing Agricultural University, and Key Laboratory of Integrated Management of Crop Diseases and Pests, Ministry of Education, Nanjing 210095, People's Republic of China
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17
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Dodonova SO, Aderhold P, Kopp J, Ganeva I, Röhling S, Hagen WJH, Sinning I, Wieland F, Briggs JAG. 9Å structure of the COPI coat reveals that the Arf1 GTPase occupies two contrasting molecular environments. eLife 2017. [PMID: 28621666 PMCID: PMC5482573 DOI: 10.7554/elife.26691] [Citation(s) in RCA: 80] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
COPI coated vesicles mediate trafficking within the Golgi apparatus and between the Golgi and the endoplasmic reticulum. Assembly of a COPI coated vesicle is initiated by the small GTPase Arf1 that recruits the coatomer complex to the membrane, triggering polymerization and budding. The vesicle uncoats before fusion with a target membrane. Coat components are structurally conserved between COPI and clathrin/adaptor proteins. Using cryo-electron tomography and subtomogram averaging, we determined the structure of the COPI coat assembled on membranes in vitro at 9 Å resolution. We also obtained a 2.57 Å resolution crystal structure of βδ-COP. By combining these structures we built a molecular model of the coat. We additionally determined the coat structure in the presence of ArfGAP proteins that regulate coat dissociation. We found that Arf1 occupies contrasting molecular environments within the coat, leading us to hypothesize that some Arf1 molecules may regulate vesicle assembly while others regulate coat disassembly. DOI:http://dx.doi.org/10.7554/eLife.26691.001
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Affiliation(s)
- Svetlana O Dodonova
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany.,Molecular Biology Department, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
| | - Patrick Aderhold
- Heidelberg University Biochemistry Center, Heidelberg University, Heidelberg, Germany
| | - Juergen Kopp
- Heidelberg University Biochemistry Center, Heidelberg University, Heidelberg, Germany
| | - Iva Ganeva
- Heidelberg University Biochemistry Center, Heidelberg University, Heidelberg, Germany
| | - Simone Röhling
- Heidelberg University Biochemistry Center, Heidelberg University, Heidelberg, Germany
| | - Wim J H Hagen
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany
| | - Irmgard Sinning
- Heidelberg University Biochemistry Center, Heidelberg University, Heidelberg, Germany
| | - Felix Wieland
- Heidelberg University Biochemistry Center, Heidelberg University, Heidelberg, Germany
| | - John A G Briggs
- Structural and Computational Biology Unit, European Molecular Biology Laboratory, Heidelberg, Germany.,Cell Biology and Biophysics Unit, European Molecular Biology Laboratory, Heidelberg, Germany.,MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
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18
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Abstract
Cell types are the basic building blocks of multicellular organisms and are extensively diversified in animals. Despite recent advances in characterizing cell types, classification schemes remain ambiguous. We propose an evolutionary definition of a cell type that allows cell types to be delineated and compared within and between species. Key to cell type identity are evolutionary changes in the 'core regulatory complex' (CoRC) of transcription factors, that make emergent sister cell types distinct, enable their independent evolution and regulate cell type-specific traits termed apomeres. We discuss the distinction between developmental and evolutionary lineages, and present a roadmap for future research.
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19
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Eicher JD, Chami N, Kacprowski T, Nomura A, Chen MH, Yanek LR, Tajuddin SM, Schick UM, Slater AJ, Pankratz N, Polfus L, Schurmann C, Giri A, Brody JA, Lange LA, Manichaikul A, Hill WD, Pazoki R, Elliot P, Evangelou E, Tzoulaki I, Gao H, Vergnaud AC, Mathias RA, Becker DM, Becker LC, Burt A, Crosslin DR, Lyytikäinen LP, Nikus K, Hernesniemi J, Kähönen M, Raitoharju E, Mononen N, Raitakari OT, Lehtimäki T, Cushman M, Zakai NA, Nickerson DA, Raffield LM, Quarells R, Willer CJ, Peloso GM, Abecasis GR, Liu DJ, Deloukas P, Samani NJ, Schunkert H, Erdmann J, Fornage M, Richard M, Tardif JC, Rioux JD, Dube MP, de Denus S, Lu Y, Bottinger EP, Loos RJF, Smith AV, Harris TB, Launer LJ, Gudnason V, Velez Edwards DR, Torstenson ES, Liu Y, Tracy RP, Rotter JI, Rich SS, Highland HM, Boerwinkle E, Li J, Lange E, Wilson JG, Mihailov E, Mägi R, Hirschhorn J, Metspalu A, Esko T, Vacchi-Suzzi C, Nalls MA, Zonderman AB, Evans MK, Engström G, Orho-Melander M, Melander O, O'Donoghue ML, Waterworth DM, Wallentin L, White HD, Floyd JS, Bartz TM, Rice KM, Psaty BM, Starr JM, Liewald DCM, Hayward C, Deary IJ, Greinacher A, Völker U, Thiele T, Völzke H, van Rooij FJA, Uitterlinden AG, Franco OH, Dehghan A, Edwards TL, Ganesh SK, Kathiresan S, Faraday N, Auer PL, Reiner AP, Lettre G, Johnson AD. Platelet-Related Variants Identified by Exomechip Meta-analysis in 157,293 Individuals. Am J Hum Genet 2016; 99:40-55. [PMID: 27346686 PMCID: PMC5005441 DOI: 10.1016/j.ajhg.2016.05.005] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Accepted: 05/03/2016] [Indexed: 12/13/2022] Open
Abstract
Platelet production, maintenance, and clearance are tightly controlled processes indicative of platelets' important roles in hemostasis and thrombosis. Platelets are common targets for primary and secondary prevention of several conditions. They are monitored clinically by complete blood counts, specifically with measurements of platelet count (PLT) and mean platelet volume (MPV). Identifying genetic effects on PLT and MPV can provide mechanistic insights into platelet biology and their role in disease. Therefore, we formed the Blood Cell Consortium (BCX) to perform a large-scale meta-analysis of Exomechip association results for PLT and MPV in 157,293 and 57,617 individuals, respectively. Using the low-frequency/rare coding variant-enriched Exomechip genotyping array, we sought to identify genetic variants associated with PLT and MPV. In addition to confirming 47 known PLT and 20 known MPV associations, we identified 32 PLT and 18 MPV associations not previously observed in the literature across the allele frequency spectrum, including rare large effect (FCER1A), low-frequency (IQGAP2, MAP1A, LY75), and common (ZMIZ2, SMG6, PEAR1, ARFGAP3/PACSIN2) variants. Several variants associated with PLT/MPV (PEAR1, MRVI1, PTGES3) were also associated with platelet reactivity. In concurrent BCX analyses, there was overlap of platelet-associated variants with red (MAP1A, TMPRSS6, ZMIZ2) and white (PEAR1, ZMIZ2, LY75) blood cell traits, suggesting common regulatory pathways with shared genetic architecture among these hematopoietic lineages. Our large-scale Exomechip analyses identified previously undocumented associations with platelet traits and further indicate that several complex quantitative hematological, lipid, and cardiovascular traits share genetic factors.
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Affiliation(s)
- John D Eicher
- Population Sciences Branch, National Heart Lung and Blood Institute, The Framingham Heart Study, Framingham, MA 01702, USA
| | - Nathalie Chami
- Department of Medicine, Université de Montréal, Montréal, QC H3T 1J4, Canada; Montreal Heart Institute, Montréal, QC H1T 1C8, Canada
| | - Tim Kacprowski
- Department of Functional Genomics, Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald and Ernst-Mortiz-Arndt University Greifswald, Greifswald 17475, Germany; DZHK (German Centre for Cardiovascular Research), partner site Greifswald, Greifswald, Germany
| | - Akihiro Nomura
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA; Program in Medical and Population Genetics, Broad Institute, Cambridge, MA 02142, USA; Cardiovascular Research Center, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Medicine, Harvard Medical School, Boston, MA 02115, USA; Division of Cardiovascular Medicine, Kanazawa University Graduate School of Medical Science, Kanazawa, Ishikawa 9200942, Japan
| | - Ming-Huei Chen
- Population Sciences Branch, National Heart Lung and Blood Institute, The Framingham Heart Study, Framingham, MA 01702, USA
| | - Lisa R Yanek
- Department of Medicine, Division of General Internal Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Salman M Tajuddin
- Laboratory of Epidemiology and Population Sciences, National Institute on Aging, NIH, Baltimore, MD 21224, USA
| | - Ursula M Schick
- The Charles Bronfman Institute for Personalized Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; The Genetics of Obesity and Related Metabolic Traits Program, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Andrew J Slater
- Genetics, Target Sciences, GlaxoSmithKline, Research Triangle Park, NC 27709, USA; OmicSoft Corporation, Cary, NC 27513, USA
| | - Nathan Pankratz
- Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, MN 55454, USA
| | - Linda Polfus
- Human Genetics Center, School of Public Health, University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Claudia Schurmann
- The Charles Bronfman Institute for Personalized Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA; The Genetics of Obesity and Related Metabolic Traits Program, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Ayush Giri
- Division of Epidemiology, Institute for Medicine and Public Health, Vanderbilt University, Nashville, TN 37235, USA
| | - Jennifer A Brody
- Department of Medicine, University of Washington, Seattle, WA 98101, USA
| | - Leslie A Lange
- Department of Genetics, University of North Carolina, Chapel Hill, NC 27514, USA
| | - Ani Manichaikul
- Center for Public Health Genomics, University of Virginia, Charlottesville, VA 22908, USA
| | - W David Hill
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh EH8 9JZ, UK; Department of Psychology, University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Raha Pazoki
- Department of Epidemiology, Erasmus MC, Rotterdam 3000, the Netherlands
| | - Paul Elliot
- Department of Epidemiology and Biostatistics, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London W2 1PG, UK
| | - Evangelos Evangelou
- Department of Epidemiology and Biostatistics, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London W2 1PG, UK; Department of Hygiene and Epidemiology, University of Ioannina Medical School, Ioannina 45110, Greece
| | - Ioanna Tzoulaki
- Department of Epidemiology and Biostatistics, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London W2 1PG, UK; Department of Hygiene and Epidemiology, University of Ioannina Medical School, Ioannina 45110, Greece
| | - He Gao
- Department of Epidemiology and Biostatistics, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London W2 1PG, UK
| | - Anne-Claire Vergnaud
- Department of Epidemiology and Biostatistics, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, London W2 1PG, UK
| | - Rasika A Mathias
- Department of Medicine, Division of General Internal Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Divisions of Allergy and Clinical Immunology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Diane M Becker
- Department of Medicine, Division of General Internal Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Lewis C Becker
- Department of Medicine, Division of General Internal Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Divisions of Cardiology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Amber Burt
- Division of Medical Genetics, Department of Medicine, University of Washington, Seattle, WA 98195, USA
| | - David R Crosslin
- Department of Biomedical Informatics and Medical Education, University of Washington, Seattle, WA 98105, USA
| | - Leo-Pekka Lyytikäinen
- Department of Clinical Chemistry, Fimlab Laboratories, Tampere 33520, Finland; Department of Clinical Chemistry, University of Tampere School of Medicine, Tampere 33514, Finland
| | - Kjell Nikus
- Department of Cardiology, Heart Center, Tampere University Hospital, Tampere 33521, Finland; University of Tampere, School of Medicine, Tampere 33514, Finland
| | - Jussi Hernesniemi
- Department of Clinical Chemistry, Fimlab Laboratories, Tampere 33520, Finland; Department of Clinical Chemistry, University of Tampere School of Medicine, Tampere 33514, Finland; Department of Cardiology, Heart Center, Tampere University Hospital, Tampere 33521, Finland
| | - Mika Kähönen
- Department of Clinical Physiology, Tampere University Hospital, Tampere 33521, Finland; Department of Clinical Physiology, University of Tampere, Tampere 33514, Finland
| | - Emma Raitoharju
- Department of Clinical Chemistry, Fimlab Laboratories, Tampere 33520, Finland; Department of Clinical Chemistry, University of Tampere School of Medicine, Tampere 33514, Finland
| | - Nina Mononen
- Department of Clinical Chemistry, Fimlab Laboratories, Tampere 33520, Finland; Department of Clinical Chemistry, University of Tampere School of Medicine, Tampere 33514, Finland
| | - Olli T Raitakari
- Department of Clinical Physiology and Nuclear Medicine, Turku University Hospital, Turku 20521, Finland; Research Centre of Applied and Preventive Cardiovascular Medicine, University of Turku, Turku 20520, Finland
| | - Terho Lehtimäki
- Department of Clinical Chemistry, Fimlab Laboratories, Tampere 33520, Finland; Department of Clinical Chemistry, University of Tampere School of Medicine, Tampere 33514, Finland
| | - Mary Cushman
- Departments of Medicine and Pathology, University of Vermont College of Medicine, Burlington, VT 05405, USA
| | - Neil A Zakai
- Departments of Medicine and Pathology, University of Vermont College of Medicine, Burlington, VT 05405, USA
| | - Deborah A Nickerson
- Department of Genome Sciences, University of Washington, Seattle, WA 98105, USA
| | - Laura M Raffield
- Department of Genetics, University of North Carolina, Chapel Hill, NC 27514, USA
| | - Rakale Quarells
- Morehouse School of Medicine, Social Epidemiology Research Center, Cardiovascular Research Institute, Atlanta, GA 30310, USA
| | - Cristen J Willer
- Department of Internal Medicine, Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, MI 48108, USA; Department of Computational Medicine and Bioinformatics, Department of Human Genetics, University of Michigan, Ann Arbor, MI 48108, USA; Department of Biostatistics, University of Michigan, Ann Arbor, MI 48108, USA
| | - Gina M Peloso
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA; Program in Medical and Population Genetics, Broad Institute, Cambridge, MA 02142, USA; Department of Biostatistics, Boston University School of Public Health, Boston, MA 02118, USA
| | - Goncalo R Abecasis
- Center for Statistical Genetics, Department of Biostatistics, University of Michigan, Ann Arbor, MI 48108, USA
| | - Dajiang J Liu
- Department of Public Health Sciences, College of Medicine, Pennsylvania State University, Hershey, PA 17033, USA
| | - Panos Deloukas
- William Harvey Research Institute, Queen Mary University London, London E1 4NS, UK; Princess Al-Jawhara Al-Brahim Centre of Excellence in Research of Hereditary Disorders (PACER-HD), King Abdulaziz University, Jeddah 21589, Saudi Arabia
| | - Nilesh J Samani
- Department of Cardiovascular Sciences, University of Leicester, Leicester LE1 7RH, UK; NIHR Leicester Cardiovascular Biomedical Research Unit, Glenfield Hospital, Leicester LE3 9QP, UK
| | - Heribert Schunkert
- DZHK (German Centre for Cardiovascular Research), partner site Munich Heart Alliance, Munich 80333, Germany; Deutsches Herzzentrum München, Technische Universität München, Munich 80333, Germany
| | - Jeanette Erdmann
- Institute for Integrative and Experimental Genomics, University of Lübeck, Lübeck 23562, Germany; DZHK (German Research Centre for Cardiovascular Research), partner site Hamburg/Lübeck/Kiel, Lübeck 23562, Germany
| | - Myriam Fornage
- Institute of Molecular Medicine, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Melissa Richard
- Institute of Molecular Medicine, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Jean-Claude Tardif
- Department of Medicine, Université de Montréal, Montréal, QC H3T 1J4, Canada; Montreal Heart Institute, Montréal, QC H1T 1C8, Canada
| | - John D Rioux
- Department of Medicine, Université de Montréal, Montréal, QC H3T 1J4, Canada; Montreal Heart Institute, Montréal, QC H1T 1C8, Canada
| | - Marie-Pierre Dube
- Department of Medicine, Université de Montréal, Montréal, QC H3T 1J4, Canada; Montreal Heart Institute, Montréal, QC H1T 1C8, Canada
| | - Simon de Denus
- Montreal Heart Institute, Montréal, QC H1T 1C8, Canada; Faculty of Pharmacy, Université de Montréal, Montréal, QC H3T 1J4, Canada
| | - Yingchang Lu
- The Charles Bronfman Institute for Personalized Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Erwin P Bottinger
- The Charles Bronfman Institute for Personalized Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Ruth J F Loos
- The Charles Bronfman Institute for Personalized Medicine, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA
| | - Albert Vernon Smith
- Icelandic Heart Association, Kopavogur 201, Iceland; Faculty of Medicine, University of Iceland, Reykjavik 101, Iceland
| | - Tamara B Harris
- Laboratory of Epidemiology, Demography, and Biometry, National Institute on Aging, Intramural Research Program, NIH, Bethesda, MD 21224, USA
| | - Lenore J Launer
- Laboratory of Epidemiology, Demography, and Biometry, National Institute on Aging, Intramural Research Program, NIH, Bethesda, MD 21224, USA
| | - Vilmundur Gudnason
- Icelandic Heart Association, Kopavogur 201, Iceland; Faculty of Medicine, University of Iceland, Reykjavik 101, Iceland
| | - Digna R Velez Edwards
- Vanderbilt Epidemiology Center, Department of Obstetrics & Gynecology, Institute for Medicine and Public Health, Vanderbilt Genetics Institute, Vanderbilt University, Nashville, TN 37203, USA
| | - Eric S Torstenson
- Division of Epidemiology, Institute for Medicine and Public Health, Vanderbilt University, Nashville, TN 37235, USA
| | - Yongmei Liu
- Center for Human Genetics, Division of Public Health Sciences, Wake Forest School of Medicine, Winston-Salem, NC 27157, USA
| | - Russell P Tracy
- Departments of Pathology and Laboratory Medicine and Biochemistry, University of Vermont College of Medicine, Colchester, VT 05446, USA
| | - Jerome I Rotter
- Institute for Translational Genomics and Population Sciences, Los Angeles Biomedical Research Institute, Torrance, CA 90502, USA; Department of Pediatrics, Harbor-UCLA Medical Center, Torrance, CA 90502, USA
| | - Stephen S Rich
- Center for Public Health Genomics, University of Virginia, Charlottesville, VA 22908, USA
| | - Heather M Highland
- The University of Texas School of Public Health, The University of Texas Graduate School of Biomedical Sciences at Houston, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA; Department of Epidemiology, University of North Carolina, Chapel Hill, NC 27514, USA
| | - Eric Boerwinkle
- Human Genetics Center, School of Public Health, University of Texas Health Science Center at Houston, Houston, TX 77030, USA; Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Jin Li
- Department of Medicine, Division of Cardiovascular Medicine, Stanford University School of Medicine, Palo Alto, CA 94305, USA
| | - Ethan Lange
- Department of Genetics, University of North Carolina, Chapel Hill, NC 27514, USA; Department of Biostatistics, University of North Carolina, Chapel Hill, NC 27514, USA
| | - James G Wilson
- Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, MS 39216, USA
| | - Evelin Mihailov
- Estonian Genome Center, University of Tartu, Tartu 51010, Estonia
| | - Reedik Mägi
- Estonian Genome Center, University of Tartu, Tartu 51010, Estonia
| | - Joel Hirschhorn
- Program in Medical and Population Genetics, Broad Institute, Cambridge, MA 02142, USA; Department of Endocrinology, Boston Children's Hospital, Boston, MA 02115, USA
| | - Andres Metspalu
- Estonian Genome Center, University of Tartu, Tartu 51010, Estonia
| | - Tõnu Esko
- Program in Medical and Population Genetics, Broad Institute, Cambridge, MA 02142, USA; Estonian Genome Center, University of Tartu, Tartu 51010, Estonia
| | - Caterina Vacchi-Suzzi
- Department of Family, Population and Preventive Medicine, Stony Brook University, Stony Brook, NY 11794, USA
| | - Mike A Nalls
- Laboratory of Neurogenetics, National Institute on Aging, NIH, Bethesda, MD 21224, USA
| | - Alan B Zonderman
- Laboratory of Epidemiology and Population Sciences, National Institute on Aging, NIH, Baltimore, MD 21224, USA
| | - Michele K Evans
- Laboratory of Epidemiology and Population Sciences, National Institute on Aging, NIH, Baltimore, MD 21224, USA
| | - Gunnar Engström
- Department of Clinical Sciences Malmö, Lund University, Malmö 221 00, Sweden; Skåne University Hospital, Malmö 222 41, Sweden
| | - Marju Orho-Melander
- Department of Clinical Sciences Malmö, Lund University, Malmö 221 00, Sweden; Skåne University Hospital, Malmö 222 41, Sweden
| | - Olle Melander
- Department of Clinical Sciences Malmö, Lund University, Malmö 221 00, Sweden; Skåne University Hospital, Malmö 222 41, Sweden
| | - Michelle L O'Donoghue
- TIMI Study Group, Cardiovascular Division, Brigham and Women's Hospital, Boston, MA 02115, USA
| | - Dawn M Waterworth
- Genetics, Target Sciences, GlaxoSmithKline, King of Prussia, PA 19406, USA
| | - Lars Wallentin
- Department of Medical Sciences, Cardiology, and Uppsala Clinical Research Center, Uppsala University, Uppsala 751 85, Sweden
| | - Harvey D White
- Green Lane Cardiovascular Service, Auckland City Hospital and University of Auckland, Auckland 1142, New Zealand
| | - James S Floyd
- Department of Medicine, University of Washington, Seattle, WA 98101, USA
| | - Traci M Bartz
- Department of Biostatistics, University of Washington, Seattle, WA 98195, USA
| | - Kenneth M Rice
- Department of Biostatistics, University of Washington, Seattle, WA 98195, USA
| | - Bruce M Psaty
- Cardiovascular Health Research Unit, Departments of Medicine, Epidemiology and Health Services, University of Washington, Seattle, WA 98101, USA; Group Health Research Institute, Group Health Cooperative, Seattle, WA 98101, USA
| | - J M Starr
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh EH8 9JZ, UK; Alzheimer Scotland Research Centre, Edinburgh EH8 9JZ, UK
| | - David C M Liewald
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh EH8 9JZ, UK; Department of Psychology, University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Caroline Hayward
- MRC Human Genetics Unit, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh EH4 2XU, UK
| | - Ian J Deary
- Centre for Cognitive Ageing and Cognitive Epidemiology, University of Edinburgh, Edinburgh EH8 9JZ, UK; Department of Psychology, University of Edinburgh, Edinburgh EH8 9JZ, UK
| | - Andreas Greinacher
- Institute for Immunology and Transfusion Medicine, University Medicine Greifswald, Greifswald 17475, Germany
| | - Uwe Völker
- Department of Functional Genomics, Interfaculty Institute for Genetics and Functional Genomics, University Medicine Greifswald and Ernst-Mortiz-Arndt University Greifswald, Greifswald 17475, Germany; DZHK (German Centre for Cardiovascular Research), partner site Greifswald, Greifswald, Germany
| | - Thomas Thiele
- Institute for Immunology and Transfusion Medicine, University Medicine Greifswald, Greifswald 17475, Germany
| | - Henry Völzke
- DZHK (German Centre for Cardiovascular Research), partner site Greifswald, Greifswald, Germany; Institute for Community Medicine, University Medicine Greifswald, Greifswald 13347, Germany
| | | | - André G Uitterlinden
- Department of Epidemiology, Erasmus MC, Rotterdam 3000, the Netherlands; Department of Internal Medicine, Erasmus MC, Rotterdam 3000, the Netherlands; Netherlands Consortium for Healthy Ageing (NCHA), Rotterdam 3015, the Netherlands
| | - Oscar H Franco
- Department of Epidemiology, Erasmus MC, Rotterdam 3000, the Netherlands
| | - Abbas Dehghan
- Department of Epidemiology, Erasmus MC, Rotterdam 3000, the Netherlands
| | - Todd L Edwards
- Division of Epidemiology, Institute for Medicine and Public Health, Vanderbilt University, Nashville, TN 37235, USA
| | - Santhi K Ganesh
- Departments of Internal and Human Genetics, University of Michigan, Ann Arbor, MI 48108, USA
| | - Sekar Kathiresan
- Center for Human Genetic Research, Massachusetts General Hospital, Boston, MA 02114, USA; Program in Medical and Population Genetics, Broad Institute, Cambridge, MA 02142, USA; Cardiovascular Research Center, Massachusetts General Hospital, Boston, MA 02114, USA; Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Nauder Faraday
- Department of Anesthesiology & Critical Care Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Paul L Auer
- Zilber School of Public Health, University of Wisconsin-Milwaukee, Milwaukee, WI 53205, USA
| | - Alex P Reiner
- Department of Epidemiology, University of Washington, Seattle, WA 98105, USA; Division of Public Health Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Guillaume Lettre
- Department of Medicine, Université de Montréal, Montréal, QC H3T 1J4, Canada; Montreal Heart Institute, Montréal, QC H1T 1C8, Canada
| | - Andrew D Johnson
- Population Sciences Branch, National Heart Lung and Blood Institute, The Framingham Heart Study, Framingham, MA 01702, USA.
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20
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Regulators and Effectors of Arf GTPases in Neutrophils. J Immunol Res 2015; 2015:235170. [PMID: 26609537 PMCID: PMC4644846 DOI: 10.1155/2015/235170] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2015] [Accepted: 09/30/2015] [Indexed: 12/22/2022] Open
Abstract
Polymorphonuclear neutrophils (PMNs) are key innate immune cells that represent the first line of defence against infection. They are the first leukocytes to migrate from the blood to injured or infected sites. This process involves molecular mechanisms that coordinate cell polarization, delivery of receptors, and activation of integrins at the leading edge of migrating PMNs. These phagocytes actively engulf microorganisms or form neutrophil extracellular traps (NETs) to trap and kill pathogens with bactericidal compounds. Association of the NADPH oxidase complex at the phagosomal membrane for production of reactive oxygen species (ROS) and delivery of proteolytic enzymes into the phagosome initiate pathogen killing and removal. G protein-dependent signalling pathways tightly control PMN functions. In this review, we will focus on the small monomeric GTPases of the Arf family and their guanine exchange factors (GEFs) and GTPase activating proteins (GAPs) as components of signalling cascades regulating PMN responses. GEFs and GAPs are multidomain proteins that control cellular events in time and space through interaction with other proteins and lipids inside the cells. The number of Arf GAPs identified in PMNs is expanding, and dissecting their functions will provide important insights into the role of these proteins in PMN physiology.
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21
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Estrada AF, Muruganandam G, Prescianotto-Baschong C, Spang A. The ArfGAP2/3 Glo3 and ergosterol collaborate in transport of a subset of cargoes. Biol Open 2015; 4:792-802. [PMID: 25964658 PMCID: PMC4571087 DOI: 10.1242/bio.011528] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Proteins reach the plasma membrane through the secretory pathway in which the trans Golgi network (TGN) acts as a sorting station. Transport from the TGN to the plasma membrane is maintained by a number of different pathways that act either directly or via the endosomal system. Here we show that a subset of cargoes depends on the ArfGAP2/3 Glo3 and ergosterol to maintain their proper localization at the plasma membrane. While interfering with neither ArfGAP2/3 activity nor ergosterol biosynthesis individually significantly altered plasma membrane localization of the tryptophan transporter Tat2, the general amino acid permease Gap1 and the v-SNARE Snc1, in a Δglo3 Δerg3 strain those proteins accumulated in internal endosomal structures. Export from the TGN to the plasma membrane and recycling from early endosomes appeared unaffected as the chitin synthase Chs3 that travels along these routes was localized normally. Our data indicate that a subset of proteins can reach the plasma membrane efficiently but after endocytosis becomes trapped in endosomal structures. Our study supports a role for ArfGAP2/3 in recycling from endosomes and in transport to the vacuole/lysosome.
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Affiliation(s)
- Alejandro F Estrada
- Growth & Development, Biozentrum, University of Basel, Klingelbergstrasse 70, 4056 Basel, Switzerland
| | - Gopinath Muruganandam
- Growth & Development, Biozentrum, University of Basel, Klingelbergstrasse 70, 4056 Basel, Switzerland
| | | | - Anne Spang
- Growth & Development, Biozentrum, University of Basel, Klingelbergstrasse 70, 4056 Basel, Switzerland
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22
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Lo IC, Gupta V, Midde KK, Taupin V, Lopez-Sanchez I, Kufareva I, Abagyan R, Randazzo PA, Farquhar MG, Ghosh P. Activation of Gαi at the Golgi by GIV/Girdin imposes finiteness in Arf1 signaling. Dev Cell 2015; 33:189-203. [PMID: 25865347 DOI: 10.1016/j.devcel.2015.02.009] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2014] [Revised: 11/25/2014] [Accepted: 02/09/2015] [Indexed: 01/22/2023]
Abstract
A long-held tenet of heterotrimeric G protein signal transduction is that it is triggered by G protein-coupled receptors (GPCRs) at the PM. Here, we demonstrate that Gi is activated in the Golgi by GIV/Girdin, a non-receptor guanine-nucleotide exchange factor (GEF). GIV-dependent activation of Gi at the Golgi maintains the finiteness of the cyclical activation of ADP-ribosylation factor 1 (Arf1), a fundamental step in vesicle traffic in all eukaryotes. Several interactions with other major components of Golgi trafficking-e.g., active Arf1, its regulator, ArfGAP2/3, and the adaptor protein β-COP-enable GIV to coordinately regulate Arf1 signaling. When the GIV-Gαi pathway is selectively inhibited, levels of GTP-bound Arf1 are elevated and protein transport along the secretory pathway is delayed. These findings define a paradigm in non-canonical G protein signaling at the Golgi, which places GIV-GEF at the crossroads between signals gated by the trimeric G proteins and the Arf family of monomeric GTPases.
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Affiliation(s)
- I-Chung Lo
- Departments of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Vijay Gupta
- Departments of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Krishna K Midde
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | - Vanessa Taupin
- Departments of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA
| | | | - Irina Kufareva
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Ruben Abagyan
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Paul A Randazzo
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892, USA
| | - Marilyn G Farquhar
- Departments of Cellular and Molecular Medicine, University of California, San Diego, La Jolla, CA 92093, USA.
| | - Pradipta Ghosh
- Department of Medicine, University of California, San Diego, La Jolla, CA 92093, USA.
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23
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Kahn RA. GAPs: Terminator versus effector functions and the role(s) of ArfGAP1 in vesicle biogenesis. CELLULAR LOGISTICS 2014; 1:49-51. [PMID: 21686252 DOI: 10.4161/cl.1.2.15153] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2011] [Accepted: 02/14/2011] [Indexed: 11/19/2022]
Abstract
Whether your passion is to understand and reverse disease processes or "simply" a better understanding of how cells work, anyone wishing to understand cell regulation today must have a detailed and accurate understanding of regulatory GTPase mechanisms and their application to specific pathways. This is becoming increasingly difficult as the details of signaling by members of different families of GTPases and their regulators expand. But this is all the more reason to continually ask, which aspects of GTPase signaling are distinct to a GTPase or its subfamily and which are conserved throughout the superfamily? We each have slightly different views of the key aspects of GTPase signaling that are derived from the main GTPases studied in our own labs; e.g., translocation onto a membrane is an essential and integral aspect of Arf activation but not of other GTPases. However, one aspect of GTPase signaling that I had come to believe to be widespread and of general importance is not universally accepted. In fact, through my conversations at the recent FASEB summer research conference on "Arf Family GTPases" and reading of the literature in a graduate tutorial class, I realized that it is not known or accepted by the majority of researchers. The question is the role of GTPase activating proteins (GAPs) in signaling. Are they "pure" terminators of signaling or do they serve effector functions?
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Affiliation(s)
- Richard A Kahn
- Department of Biochemistry; Emory University School of Medicine; Atlanta, GA USA
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24
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Beck R, Brügger B, Wieland F. GAPs in the context of COPI: Enzymes, coat components or both? CELLULAR LOGISTICS 2014; 1:52-54. [PMID: 21686253 DOI: 10.4161/cl.1.2.15174] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2011] [Accepted: 02/15/2011] [Indexed: 02/02/2023]
Abstract
TRAFFICKING IN THE EARLY SECRETORY PATHWAY AT FIRST GLANCE IS WELL UNDERSTOOD ACCORDING TO TEXTBOOK KNOWLEDGE: To achieve secretion and to maintain organelle homeostasis, protein and lipid cargo need to be transported constitutively from their origins of biosynthesis to their respective destinations. Thus, secretory cargo exits the ER and is shuttled to the Golgi via vesicular COPII carriers. Lipid and protein cargo is enzymatically modified in the Golgi, transported from cis- to trans- (by mechanisms that are still debated today), and from there travel to their final destinations. The best established roles for COPI vesicles, simply spoken, is to mediate retrograde trafficking of cargo molecules that were transported forward, but need to be transported back.
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Affiliation(s)
- Rainer Beck
- Department of Cell Biology; Yale University School of Medicine; New Haven, CT USA
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25
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Vanni S, Hirose H, Barelli H, Antonny B, Gautier R. A sub-nanometre view of how membrane curvature and composition modulate lipid packing and protein recruitment. Nat Commun 2014; 5:4916. [PMID: 25222832 DOI: 10.1038/ncomms5916] [Citation(s) in RCA: 189] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Accepted: 08/05/2014] [Indexed: 02/07/2023] Open
Abstract
Two parameters of biological membranes, curvature and lipid composition, direct the recruitment of many peripheral proteins to cellular organelles. Although these traits are often studied independently, it is their combination that generates the unique interfacial properties of cellular membranes. Here, we use a combination of in vivo, in vitro and in silico approaches to provide a comprehensive map of how these parameters modulate membrane adhesive properties. The correlation between the membrane partitioning of model amphipathic helices and the distribution of lipid-packing defects in membranes of different shape and composition explains how macroscopic membrane properties modulate protein recruitment by changing the molecular topography of the membrane interfacial region. Furthermore, our results suggest that the range of conditions that can be obtained in a cellular context is remarkably large because lipid composition and curvature have, under most circumstances, cumulative effects.
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Affiliation(s)
- Stefano Vanni
- 1] Institut de Pharmacologie Moléculaire et Cellulaire, Université de Nice Sophia-Antipolis and Centre National de la Recherche Scientifique, UMR 7275, 660 route des Lucioles, 06560 Valbonne, France [2]
| | - Hisaaki Hirose
- 1] Institut de Pharmacologie Moléculaire et Cellulaire, Université de Nice Sophia-Antipolis and Centre National de la Recherche Scientifique, UMR 7275, 660 route des Lucioles, 06560 Valbonne, France [2]
| | - Hélène Barelli
- Institut de Pharmacologie Moléculaire et Cellulaire, Université de Nice Sophia-Antipolis and Centre National de la Recherche Scientifique, UMR 7275, 660 route des Lucioles, 06560 Valbonne, France
| | - Bruno Antonny
- Institut de Pharmacologie Moléculaire et Cellulaire, Université de Nice Sophia-Antipolis and Centre National de la Recherche Scientifique, UMR 7275, 660 route des Lucioles, 06560 Valbonne, France
| | - Romain Gautier
- Institut de Pharmacologie Moléculaire et Cellulaire, Université de Nice Sophia-Antipolis and Centre National de la Recherche Scientifique, UMR 7275, 660 route des Lucioles, 06560 Valbonne, France
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26
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Wittinghofer A. Arf Proteins and Their Regulators: At the Interface Between Membrane Lipids and the Protein Trafficking Machinery. RAS SUPERFAMILY SMALL G PROTEINS: BIOLOGY AND MECHANISMS 2 2014. [PMCID: PMC7123483 DOI: 10.1007/978-3-319-07761-1_8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
The Arf small GTP-binding (G) proteins regulate membrane traffic and organelle structure in eukaryotic cells through a regulated cycle of GTP binding and hydrolysis. The first function identified for Arf proteins was recruitment of cytosolic coat complexes to membranes to mediate vesicle formation. However, subsequent studies have uncovered additional functions, including roles in plasma membrane signalling pathways, cytoskeleton regulation, lipid droplet function, and non-vesicular lipid transport. In contrast to other families of G proteins, there are only a few Arf proteins in each organism, yet they function specifically at many different cellular locations. Part of this specificity is achieved by formation of complexes with their guanine nucleotide-exchange factors (GEFs) and GTPase activating proteins (GAPs) that catalyse GTP binding and hydrolysis, respectively. Because these regulators outnumber their Arf substrates by at least 3-to-1, an important aspect of understanding Arf function is elucidating the mechanisms by which a single Arf protein is incorporated into different GEF, GAP, and effector complexes. New insights into these mechanisms have come from recent studies showing GEF–effector interactions, Arf activation cascades, and positive feedback loops. A unifying theme in the function of Arf proteins, carried out in conjunction with their regulators and effectors, is sensing and modulating the properties of the lipids that make up cellular membranes.
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Affiliation(s)
- Alfred Wittinghofer
- Max-Planck-Institute of Molecular Physiology, Dortmund, Nordrhein-Westfalen Germany
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27
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Shiba Y, Kametaka S, Waguri S, Presley JF, Randazzo PA. ArfGAP3 regulates the transport of cation-independent mannose 6-phosphate receptor in the post-Golgi compartment. Curr Biol 2013; 23:1945-51. [PMID: 24076238 PMCID: PMC3795807 DOI: 10.1016/j.cub.2013.07.087] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2013] [Revised: 06/25/2013] [Accepted: 07/31/2013] [Indexed: 10/26/2022]
Abstract
ArfGAPs are known to be involved in cargo sorting in COPI transport. However, the role of ArfGAPs in post-Golgi membrane traffic has not been defined. To determine the function of ArfGAPs in post-Golgi traffic, we used small interfering RNA to examine each of 25 ArfGAPs for effects on cation-independent mannose 6-phosphate receptor (CIMPR) localization. We found that downregulation of ArfGAP3 resulted in the peripheral localization of CIMPR. The effect was specific for ArfGAP3 and dependent on its GAP activity, because the phenotype was rescued by ArfGAP3 but not by ArfGAP1, ArfGAP2, or the GAP domain mutants of ArfGAP3. ArfGAP3 localized to the trans-Golgi network and early endosomes. In cells with reduced expression of ArfGAP3, Cathepsin D maturation was slowed and its secretion was accelerated. Also retrograde transport from the endosomes to the trans-Golgi network of endogenous CIMPR, but not truncated CIMPR lacking the luminal domain, was perturbed in cells with reduced expression of ArfGAP3. Furthermore the exit of epidermal growth factor receptor (EGFR) from the early endosomes and degradation of EGFR after EGF stimulation was slowed in cells with reduced expression of ArfGAP3. ArfGAP3 associates with Golgi-localized, γ-ear-containing, ADP-ribosylation factor binding proteins (GGAs), and ArfGAP3 knockdown reduces membrane association of GGAs. A possible mechanism explaining our results is that ArfGAP3 regulates transport from early endosomes to late endosomes. We suggest a model in which ArfGAP3 regulates Golgi association of GGA clathrin adaptors.
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Affiliation(s)
- Yoko Shiba
- Laboratory of Cellular and Molecular Biology, National Cancer Institute, Bethesda, MD, USA
| | - Satoshi Kametaka
- Department of Anatomy and Histology, Fukushima Medical University, Fukushima, Japan
| | - Satoshi Waguri
- Department of Anatomy and Histology, Fukushima Medical University, Fukushima, Japan
| | - John F. Presley
- Department of Anatomy and Cell Biology, McGill University, Montreal, Canada
| | - Paul Agostino Randazzo
- Laboratory of Cellular and Molecular Biology, National Cancer Institute, Bethesda, MD, USA
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28
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COPI buds 60-nm lipid droplets from reconstituted water-phospholipid-triacylglyceride interfaces, suggesting a tension clamp function. Proc Natl Acad Sci U S A 2013; 110:13244-9. [PMID: 23901109 DOI: 10.1073/pnas.1307685110] [Citation(s) in RCA: 120] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Intracellular trafficking between organelles is achieved by coat protein complexes, coat protomers, that bud vesicles from bilayer membranes. Lipid droplets are protected by a monolayer and thus seem unsuitable targets for coatomers. Unexpectedly, coat protein complex I (COPI) is required for lipid droplet targeting of some proteins, suggesting a possible direct interaction between COPI and lipid droplets. Here, we find that COPI coat components can bud 60-nm triacylglycerol nanodroplets from artificial lipid droplet (LD) interfaces. This budding decreases phospholipid packing of the monolayer decorating the mother LD. As a result, hydrophobic triacylglycerol molecules become more exposed to the aqueous environment, increasing LD surface tension. In vivo, this surface tension increase may prime lipid droplets for reactions with neighboring proteins or membranes. It provides a mechanism fundamentally different from transport vesicle formation by COPI, likely responsible for the diverse lipid droplet phenotypes associated with depletion of COPI subunits.
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29
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Adolf F, Herrmann A, Hellwig A, Beck R, Brügger B, Wieland FT. Scission of COPI and COPII vesicles is independent of GTP hydrolysis. Traffic 2013; 14:922-32. [PMID: 23691917 DOI: 10.1111/tra.12084] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2012] [Revised: 05/15/2013] [Accepted: 05/20/2013] [Indexed: 12/29/2022]
Abstract
Intracellular transport and maintenance of the endomembrane system in eukaryotes depends on formation and fusion of vesicular carriers. A seeming discrepancy exists in the literature about the basic mechanism in the scission of transport vesicles that depend on GTP-binding proteins. Some reports describe that the scission of COP-coated vesicles is dependent on GTP hydrolysis, whereas others found that GTP hydrolysis is not required. In order to investigate this pivotal mechanism in vesicle formation, we analyzed formation of COPI- and COPII-coated vesicles utilizing semi-intact cells. The small GTPases Sar1 and Arf1 together with their corresponding coat proteins, the Sec23/24 and Sec13/31 complexes for COPII and coatomer for COPI vesicles were required and sufficient to drive vesicle formation. Both types of vesicles were efficiently generated when GTP hydrolysis was blocked either by utilizing the poorly hydrolyzable GTP analogs GTPγS and GMP-PNP, or with constitutively active mutants of the small GTPases. Thus, GTP hydrolysis is not required for the formation and release of COP vesicles.
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Affiliation(s)
- Frank Adolf
- Heidelberg University Biochemistry Center, University of Heidelberg, Im Neuenheimer Feld 328, D-69120, Heidelberg, Germany
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30
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Spang A. Retrograde traffic from the Golgi to the endoplasmic reticulum. Cold Spring Harb Perspect Biol 2013; 5:5/6/a013391. [PMID: 23732476 DOI: 10.1101/cshperspect.a013391] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Proteins to be secreted are transported from the endoplasmic reticulum (ER) to the Golgi apparatus. The transport of these proteins requires the localization and activity of proteins that create ER exit sites, coat proteins to collect cargo and to reshape the membrane into a transport container, and address labels--SNARE proteins--to target the vesicles specifically to the Golgi apparatus. In addition some proteins may need export chaperones or export receptors to enable their exit into transport vesicles. ER export factors, SNAREs, and misfolded Golgi-resident proteins must all be retrieved from the Golgi to the ER again. This retrieval is also part of the organellar homeostasis pathway essential to maintaining the identity of the ER and of the Golgi apparatus. In this review, I will discuss the different processes in retrograde transport from the Golgi to the ER and highlight the mechanistic insights we have obtained in the last couple of years.
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Affiliation(s)
- Anne Spang
- University of Basel, Biozentrum, Growth & Development, Klingelbergstrasse 70, 4056 Basel, Switzerland.
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31
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Min MK, Jang M, Lee M, Lee J, Song K, Lee Y, Choi KY, Robinson DG, Hwang I. Recruitment of Arf1-GDP to Golgi by Glo3p-type ArfGAPs is crucial for golgi maintenance and plant growth. PLANT PHYSIOLOGY 2013; 161:676-91. [PMID: 23266962 PMCID: PMC3561012 DOI: 10.1104/pp.112.209148] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Accepted: 12/23/2012] [Indexed: 05/20/2023]
Abstract
ADP-ribosylation factor1 (Arf1), a member of the small GTP-binding proteins, plays a pivotal role in protein trafficking to multiple organelles. In its GDP-bound form, Arf1 is recruited from the cytosol to organelle membranes, where it functions in vesicle-mediated protein trafficking. However, the mechanism of Arf1-GDP recruitment remains unknown. Here, we provide evidence that two Glo3p-type Arf GTPase-activating proteins (ArfGAPs), ArfGAP domain8 (AGD8) and AGD9, are involved in the recruitment of Arf1-GDP to the Golgi apparatus in Arabidopsis (Arabidopsis thaliana). RNA interference plants expressing low levels of AGD8 and AGD9 exhibited abnormal Golgi morphology, inhibition of protein trafficking, and arrest of plant growth and development. In RNA interference plants, Arf1 was poorly recruited to the Golgi apparatus. Conversely, high levels of AGD8 and AGD9 induced Arf1 accumulation at the Golgi and suppressed Golgi disruption and inhibition of vacuolar trafficking that was caused by overexpression of AGD7. Based on these results, we propose that the Glo3p-type ArfGAPs AGD8 and AGD9 recruit Arf1-GDP from the cytosol to the Golgi for Arf1-mediated protein trafficking, which is essential for plant development and growth.
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32
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Shiba Y, Randazzo PA. ArfGAP1 function in COPI mediated membrane traffic: currently debated models and comparison to other coat-binding ArfGAPs. Histol Histopathol 2012; 27:1143-53. [PMID: 22806901 DOI: 10.14670/hh-27.1143] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The ArfGAPs are a family of proteins containing an ArfGAP catalytic domain that induces the hydrolysis of GTP bound to the small guanine nucleotide binding-protein ADP-ribosylation factor (Arf). Functional models for Arfs, which are regulators of membrane traffic, are based on the idea that guanine nucleotide-binding proteins function as switches: Arf with GTP bound is active and binds to effector proteins; the conversion of GTP to GDP inactivates Arf. The cellular activities of ArfGAPs have been examined primarily as regulatory proteins that inactivate Arf; however, Arf function in membrane traffic does not strictly adhere to the concept of a simple switch, adding complexity to models explaining the role of ArfGAPs. Here, we review the literature addressing the function Arf and ArfGAP1 in COPI mediated transport, focusing on two critical and integrated functions of membrane traffic, cargo sorting and vesicle coat polymerization. We briefly discuss other ArfGAPs that may have similar function in Arf-dependent membrane traffic outside the ER-Golgi.
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Affiliation(s)
- Yoko Shiba
- National Cancer Institute, Laboratory of Cellular and Molecular Biology, Bethesda, MD 20892, USA
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33
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Cottam NP, Ungar D. Retrograde vesicle transport in the Golgi. PROTOPLASMA 2012; 249:943-55. [PMID: 22160157 DOI: 10.1007/s00709-011-0361-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Accepted: 11/29/2011] [Indexed: 05/23/2023]
Abstract
The Golgi apparatus is the central sorting and biosynthesis hub of the secretory pathway, and uses vesicle transport for the recycling of its resident enzymes. This system must operate with high fidelity and efficiency for the correct modification of secretory glycoconjugates. In this review, we discuss recent advances on how coats, tethers, Rabs and SNAREs cooperate at the Golgi to achieve vesicle transport. We cover the well understood vesicle formation process orchestrated by the COPI coat, and the comprehensively documented fusion process governed by a set of Golgi localised SNAREs. Much less clear are the steps in-between formation and fusion of vesicles, and we therefore provide a much needed update of the latest findings about vesicle tethering. The interplay between Rab GTPases, golgin family coiled-coil tethers and the conserved oligomeric Golgi (COG) complex at the Golgi are thoroughly evaluated.
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Affiliation(s)
- Nathanael P Cottam
- Department of Biology (Area 9), University of York, Heslington, York, YO10 5DD, UK
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34
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Pevzner I, Strating J, Lifshitz L, Parnis A, Glaser F, Herrmann A, Brügger B, Wieland F, Cassel D. Distinct role of subcomplexes of the COPI coat in the regulation of ArfGAP2 activity. Traffic 2012; 13:849-56. [PMID: 22375848 DOI: 10.1111/j.1600-0854.2012.01349.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2012] [Revised: 02/27/2012] [Accepted: 02/29/2012] [Indexed: 11/29/2022]
Abstract
COPI vesicles serve for transport of proteins and membrane lipids in the early secretory pathway. Their coat protein (coatomer) is a heptameric complex that is recruited to the Golgi by the small GTPase Arf1. Although recruited en bloc, coatomer can be viewed as a stable assembly of an adaptin-like tetrameric subcomplex (CM4) and a trimeric 'cage' subcomplex (CM3). Following recruitment, coatomer stimulates ArfGAP-dependent GTP hydrolysis on Arf1. Here, we employed recombinant coatomer subcomplexes to study the role of coatomer components in the regulation of ArfGAP2, an ArfGAP whose activity is strictly coatomer-dependent. Within CM4, we define a novel hydrophobic pocket for ArfGAP2 interaction on the appendage domain of γ₁-COP. The CM4 subcomplex (but not CM3) is recruited to membranes through Arf1 and can subsequently recruit ArfGAP2. Neither CM3 nor CM4 in itself is effective in stimulating ArfGAP2 activity, but stimulation is regained when both subcomplexes are present. Our findings point to a distinct role of each of the two coatomer subcomplexes in the regulation of ArfGAP2-dependent GTP hydrolysis on Arf1, where the CM4 subcomplex functions in GAP recruitment, while, similarly to the COPII system, the cage-like CM3 subcomplex stimulates the catalytic reaction.
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Affiliation(s)
- Irit Pevzner
- Department of Biology, Technion-Israel Institute of Technology, Haifa 32000, Israel
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35
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Luo R, Akpan IO, Hayashi R, Sramko M, Barr V, Shiba Y, Randazzo PA. GTP-binding protein-like domain of AGAP1 is protein binding site that allosterically regulates ArfGAP protein catalytic activity. J Biol Chem 2012; 287:17176-17185. [PMID: 22453919 DOI: 10.1074/jbc.m111.334458] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
AGAPs are a subtype of Arf GTPase-activating proteins (GAPs) with 11 members in humans. In addition to the Arf GAP domain, the proteins contain a G-protein-like domain (GLD) with homology to Ras superfamily proteins and a PH domain. AGAPs bind to clathrin adaptors, function in post Golgi membrane traffic, and have been implicated in glioblastoma. The regulation of AGAPs is largely unexplored. Other enzymes containing GTP binding domains are regulated by nucleotide binding. However, nucleotide binding to AGAPs has not been detected. Here, we found that neither nucleotides nor deleting the GLD of AGAP1 affected catalysis, which led us to hypothesize that the GLD is a protein binding site that regulates GAP activity. Two-hybrid screens identified RhoA, Rac1, and Cdc42 as potential binding partners. Coimmunoprecipitation confirmed that AGAP1 and AGAP2 can bind to RhoA. Binding was mediated by the C terminus of RhoA and was independent of nucleotide. RhoA and the C-terminal peptide from RhoA increased GAP activity specifically for the substrate Arf1. In contrast, a C-terminal peptide from Cdc42 neither bound nor activated AGAP1. Based on these results, we propose that AGAPs are allosterically regulated through protein binding to the GLD domain.
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Affiliation(s)
- Ruibai Luo
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20892
| | - Itoro O Akpan
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20892
| | - Ryo Hayashi
- Department of Chemistry, Faculty of Science and Engineering, Saga University, Honjo, Saga 840-8502, Japan
| | - Marek Sramko
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20892
| | - Valarie Barr
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20892
| | - Yoko Shiba
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20892
| | - Paul A Randazzo
- Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland 20892.
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36
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Beck R, Prinz S, Diestelkötter-Bachert P, Röhling S, Adolf F, Hoehner K, Welsch S, Ronchi P, Brügger B, Briggs JAG, Wieland F. Coatomer and dimeric ADP ribosylation factor 1 promote distinct steps in membrane scission. ACTA ACUST UNITED AC 2012; 194:765-77. [PMID: 21893600 PMCID: PMC3171119 DOI: 10.1083/jcb.201011027] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
During membrane budding, coatomer drives initial curvature of the bud, whereas dimeric Arf1 is necessary for membrane scission. Formation of coated vesicles requires two striking manipulations of the lipid bilayer. First, membrane curvature is induced to drive bud formation. Second, a scission reaction at the bud neck releases the vesicle. Using a reconstituted system for COPI vesicle formation from purified components, we find that a dimerization-deficient Arf1 mutant, which does not display the ability to modulate membrane curvature in vitro or to drive formation of coated vesicles, is able to recruit coatomer to allow formation of COPI-coated buds but does not support scission. Chemical cross-linking of this Arf1 mutant restores vesicle release. These experiments show that initial curvature of the bud is defined primarily by coatomer, whereas the membrane curvature modulating activity of dimeric Arf1 is required for membrane scission.
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Affiliation(s)
- Rainer Beck
- Heidelberg University Biochemistry Center, Heidelberg University, 69120 Heidelberg, Germany
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37
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Popoff V, Adolf F, Brügger B, Wieland F. COPI budding within the Golgi stack. Cold Spring Harb Perspect Biol 2011; 3:a005231. [PMID: 21844168 DOI: 10.1101/cshperspect.a005231] [Citation(s) in RCA: 119] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The Golgi serves as a hub for intracellular membrane traffic in the eukaryotic cell. Transport within the early secretory pathway, that is within the Golgi and from the Golgi to the endoplasmic reticulum, is mediated by COPI-coated vesicles. The COPI coat shares structural features with the clathrin coat, but differs in the mechanisms of cargo sorting and vesicle formation. The small GTPase Arf1 initiates coating on activation and recruits en bloc the stable heptameric protein complex coatomer that resembles the inner and the outer shells of clathrin-coated vesicles. Different binding sites exist in coatomer for membrane machinery and for the sorting of various classes of cargo proteins. During the budding of a COPI vesicle, lipids are sorted to give a liquid-disordered phase composition. For the release of a COPI-coated vesicle, coatomer and Arf cooperate to mediate membrane separation.
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Affiliation(s)
- Vincent Popoff
- Heidelberg University Biochemistry Center, 69120 Heidelberg, Germany
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38
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Cook WJ, Senkovich O, Chattopadhyay D. Structure of the catalytic domain of Plasmodium falciparum ARF GTPase-activating protein (ARFGAP). Acta Crystallogr Sect F Struct Biol Cryst Commun 2011; 67:1339-44. [PMID: 22102228 PMCID: PMC3212447 DOI: 10.1107/s1744309111032507] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Accepted: 08/10/2011] [Indexed: 11/11/2022]
Abstract
The crystal structure of the catalytic domain of the ADP ribosylation factor GTPase-activating protein (ARFGAP) from Plasmodium falciparum has been determined and refined to 2.4 Å resolution. Multiwavength anomalous diffraction (MAD) data were collected utilizing the Zn(2+) ion bound at the zinc-finger domain and were used to solve the structure. The overall structure of the domain is similar to those of mammalian ARFGAPs. However, several amino-acid residues in the area where GAP interacts with ARF1 differ in P. falciparum ARFGAP. Moreover, a number of residues that form the dimer interface in the crystal structure are unique in P. falciparum ARFGAP.
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Affiliation(s)
- William J. Cook
- Department of Medicine, University of Alabama at Birmingham, CBSE-250, 1015 18th Street South, Birmingham, AL 35294, USA
| | - Olga Senkovich
- Department of Medicine, University of Alabama at Birmingham, CBSE-250, 1015 18th Street South, Birmingham, AL 35294, USA
| | - Debasish Chattopadhyay
- Department of Medicine, University of Alabama at Birmingham, CBSE-250, 1015 18th Street South, Birmingham, AL 35294, USA
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39
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Abstract
Bacteria and eukaryotic cells contain geometry-sensing tools in their cytosol: protein motifs or domains that recognize the curvature, concave or convex, deep or shallow, of lipid membranes. These sensors contrast with classical lipid-binding domains by their extended structure and, sometimes, counterintuitive chemistry. Among the sensors are long amphipathic helices, such as the ALPS motif and the N-terminal region of α-synuclein, whose apparent "design defects" translate into a remarkable ability to specifically adsorb to the surface of small vesicles. Fundamental differences in the lipid composition of membranes of the early and late secretory pathways probably explain why some sensors use mostly electrostatics whereas others take advantage of the hydrophobic effect. Membrane curvature sensors help to organize very diverse reactions, such as lipid transfer between membranes, the tethering of vesicles at the Golgi apparatus, and the assembly-disassembly cycle of protein coats.
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Affiliation(s)
- Bruno Antonny
- Université de Nice-Sophia Antipolis and Centre National de la Recheche Scientifique, Institut de Pharmacologie Moléculaire et Cellulaire, 06560 Valbonne, France.
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40
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Meierhofer T, Eberhardt M, Spoerner M. Conformational states of ADP ribosylation factor 1 complexed with different guanosine triphosphates as studied by 31P NMR spectroscopy. Biochemistry 2011; 50:6316-27. [PMID: 21702511 DOI: 10.1021/bi101573j] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Guanine nucleotide binding proteins (GNB-proteins) play an essential role in cellular signaling, acting as molecular switches, cycling between the inactive, GDP-bound form and the active, GTP-bound form. It has been shown that conformational equilibria also exist within the active form of GNB-proteins between conformational states with different functional properties. Here we present (31)P NMR data on ADP ribosylation factor 1 (Arf1), a GNB-protein involved in Golgi traffic, promoting the coating of secretory vesicles. To investigate conformational equilibria in active Arf1, the wild type and switch I mutants complexed with GTP and a variety of commonly used GTP analogues, namely, GppCH(2)p, GppNHp, and GTPγS, were analyzed. To gain deeper insight into the conformational state of active Arf1, we titrated with Cu(2+)-cyclen and GdmCl and formed the complex with the Sec7 domain of nucleotide exchange factor ARNO and an effector GAT domain. In contrast to the related proteins Ras, Ral, Cdc42, and Ran, from (31)P NMR spectroscopic view, Arf1 exists predominantly in a single conformation independent of the GTP analogue used. This state seems to correspond to the so-called state 2(T) conformation, according to Ras nomenclature, which is interacting with the effector domain. The exchange of the highly conserved threonine in position 48 with alanine led to a shift of the equilibrium toward a conformational state with typical properties obtained for state 1(T) in Ras, such as interaction with guanine nucleotide exchange factors, a lower affinity for nucleoside triphosphates, and greater sensitivity to chaotropic agents. In active Arf1(wt), the effector interacting conformation is strongly favored. These intrinsic conformational equilibria of active GNB-proteins could be a fine-tuning mechanism of regulation and thereby an interesting target for the modulation of protein activity.
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Affiliation(s)
- Tanja Meierhofer
- University of Regensburg, Institute of Biophysics and Physical Biochemistry, Universitätsstrasse 31, D-93053 Regensburg, Germany
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41
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Shiba Y, Luo R, Hinshaw JE, Szul T, Hayashi R, Sztul E, Nagashima K, Baxa U, Randazzo PA. ArfGAP1 promotes COPI vesicle formation by facilitating coatomer polymerization. CELLULAR LOGISTICS 2011; 1:139-154. [PMID: 22279613 PMCID: PMC3265926 DOI: 10.4161/cl.1.4.18896] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Revised: 11/21/2011] [Accepted: 11/29/2011] [Indexed: 12/31/2022]
Abstract
The role of ArfGAP1 in COPI vesicle biogenesis has been controversial. In work using isolated Golgi membranes, ArfGAP1 was found to promote COPI vesicle formation. In contrast, in studies using large unilamellar vesicles (LUVs) as model membranes, ArfGAP1 functioned as an uncoating factor inhibiting COPI vesicle formation. We set out to discriminate between these models. First, we reexamined the effect of ArfGAP1 on LUVs. We found that ArfGAP1 increased the efficiency of coatomer-induced deformation of LUVs. Second, ArfGAP1 and peptides from cargo facilitated self-assembly of coatomer into spherical structures in the absence of membranes, reminiscent of clathrin self-assembly. Third, in vivo, ArfGAP1 overexpression induced the accumulation of vesicles and allowed normal trafficking of a COPI cargo. Taken together, these data support the model in which ArfGAP1 promotes COPI vesicle formation and membrane traffic and identify a function for ArfGAP1 in the assembly of coatomer into COPI.
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Affiliation(s)
- Yoko Shiba
- Laboratory of Cellular and Molecular Biology; National Cancer Institute, Bethesda, MD USA
| | - Ruibai Luo
- Laboratory of Cellular and Molecular Biology; National Cancer Institute, Bethesda, MD USA
| | - Jenny E Hinshaw
- National Institute of Diabetes and Digestive and Kidney Disease; National Institutes of Health; Bethesda, MD USA
| | - Tomasz Szul
- Department of Cell Biology; The University of Alabama at Birmingham; Birmingham, AL USA
| | - Ryo Hayashi
- Laboratory of Cell Biology; National Cancer Institute; Bethesda, MD USA
| | - Elizabeth Sztul
- Department of Cell Biology; The University of Alabama at Birmingham; Birmingham, AL USA
| | - Kunio Nagashima
- Electron Microscopy Laboratory, ATP, SAIC-Frederick, Center for Cancer Research, National Cancer Institute; Frederick, MD USA
| | - Ulrich Baxa
- Electron Microscopy Laboratory, ATP, SAIC-Frederick, Center for Cancer Research, National Cancer Institute; Frederick, MD USA
| | - Paul A Randazzo
- Laboratory of Cellular and Molecular Biology; National Cancer Institute, Bethesda, MD USA
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42
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Hsu VW. Role of ArfGAP1 in COPI vesicle biogenesis. CELLULAR LOGISTICS 2011; 1:55-56. [PMID: 21686254 PMCID: PMC3116587 DOI: 10.4161/cl.1.2.15175] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2011] [Accepted: 02/15/2011] [Indexed: 11/19/2022]
Abstract
Studies from our group suggest that ArfGAP1 acts not only as an Arf regulator but also as an Arf effector, with both roles promoting COPI vesicle formation. However, others have concluded differently, specifically that ArfGAP1 only acts as an Arf regulator, which involves inhibition of COPI vesicle formation by preventing components of the COPI complex from binding to target membrane. Here, we propose plausible reconciling explanations for this apparent contradiction.
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Affiliation(s)
- Victor W Hsu
- Brigham and Women's Hospital; Harvard Medical School; Boston, MA USA
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43
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44
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Kartberg F, Asp L, Dejgaard SY, Smedh M, Fernandez-Rodriguez J, Nilsson T, Presley JF. ARFGAP2 and ARFGAP3 are essential for COPI coat assembly on the Golgi membrane of living cells. J Biol Chem 2010; 285:36709-20. [PMID: 20858901 DOI: 10.1074/jbc.m110.180380] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Coat protein complex I (COPI) vesicles play a central role in the recycling of proteins in the early secretory pathway and transport of proteins within the Golgi stack. Vesicle formation is initiated by the exchange of GDP for GTP on ARF1 (ADP-ribosylation factor 1), which, in turn, recruits the coat protein coatomer to the membrane for selection of cargo and membrane deformation. ARFGAP1 (ARF1 GTPase-activating protein 1) regulates the dynamic cycling of ARF1 on the membrane that results in both cargo concentration and uncoating for the generation of a fusion-competent vesicle. Two human orthologues of the yeast ARFGAP Glo3p, termed ARFGAP2 and ARFGAP3, have been demonstrated to be present on COPI vesicles generated in vitro in the presence of guanosine 5'-3-O-(thio)triphosphate. Here, we investigate the function of these two proteins in living cells and compare it with that of ARFGAP1. We find that ARFGAP2 and ARFGAP3 follow the dynamic behavior of coatomer upon stimulation of vesicle budding in vivo more closely than does ARFGAP1. Electron microscopy of ARFGAP2 and ARFGAP3 knockdowns indicated Golgi unstacking and cisternal shortening similarly to conditions where vesicle uncoating was blocked. Furthermore, the knockdown of both ARFGAP2 and ARFGAP3 prevents proper assembly of the COPI coat lattice for which ARFGAP1 does not seem to play a major role. This suggests that ARFGAP2 and ARFGAP3 are key components of the COPI coat lattice and are necessary for proper vesicle formation.
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Affiliation(s)
- Fredrik Kartberg
- Department of Medical and Clinical Genetics, Institute of Biomedicine, University of Gothenburg, 405 30 Göteborg, Sweden
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45
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East MP, Kahn RA. Models for the functions of Arf GAPs. Semin Cell Dev Biol 2010; 22:3-9. [PMID: 20637885 DOI: 10.1016/j.semcdb.2010.07.002] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2010] [Revised: 07/02/2010] [Accepted: 07/07/2010] [Indexed: 11/27/2022]
Abstract
Arf GAPs (ADP-ribosylation factor GTPase-activating proteins) are essential components of Arf (ADP-ribosylation factor) signaling pathways. Arf GAPs stimulate the hydrolysis of GTP to GDP to transition Arf from the active, GTP bound, state to the inactive, GDP bound, state. Based on this activity, Arf GAPs were initially proposed to function primarily or exclusively as terminators of Arf signaling. Further studies of Arf GAPs have revealed that they also function as effectors of Arf signaling in at least a few steps or processes in which Arfs are not directly involved. In this review we discuss the non-canonical functions of Arf GAPs and address several key questions in the field, including: whether (1) Arf GAPs are terminators or effectors of Arf signaling, (2) Arf GAPs positively or negatively regulate COPI assembly, (3) Arf GAPs are involved in vesicle fission, and (4) Arf GAPs regulate vesicle uncoating.
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Affiliation(s)
- Michael P East
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA 30322-3050, USA.
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46
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Ismail SA, Vetter IR, Sot B, Wittinghofer A. The structure of an Arf-ArfGAP complex reveals a Ca2+ regulatory mechanism. Cell 2010; 141:812-21. [PMID: 20510928 DOI: 10.1016/j.cell.2010.03.051] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2009] [Revised: 01/15/2010] [Accepted: 03/22/2010] [Indexed: 10/19/2022]
Abstract
Arfs are small G proteins that have a key role in vesicle trafficking and cytoskeletal remodeling. ArfGAP proteins stimulate Arf intrinsic GTP hydrolysis by a mechanism that is still unresolved. Using a fusion construct we solved the structure of the ArfGAP ASAP3 in complex with Arf6 in the transition state. This structure clarifies the ArfGAP catalytic mechanism and shows a glutamine((Arf6)) and an arginine finger((ASAP3)) as the important catalytic residues. Unexpectedly the structure shows a calcium ion, liganded by both proteins in the complex interface, stabilizing the interaction and orienting the catalytic machinery. Calcium stimulates the GAP activity of ASAPs, but not other members of the ArfGAP family. This type of regulation is unique for GAPs and any other calcium-regulated processes and hints at a crosstalk between Ca(2+) and Arf signaling.
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Affiliation(s)
- Shehab A Ismail
- Department of Structural Biology, Max-Planck-Institute für Molekulare Physiologie, Dortmund 44227, Germany
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47
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Spang A, Shiba Y, Randazzo PA. Arf GAPs: gatekeepers of vesicle generation. FEBS Lett 2010; 584:2646-51. [PMID: 20394747 DOI: 10.1016/j.febslet.2010.04.005] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2010] [Revised: 03/26/2010] [Accepted: 04/03/2010] [Indexed: 11/17/2022]
Abstract
Arf GAP proteins are a versatile and diverse group of proteins. They control the activity of the GTP-binding proteins of the ARF family by inducing the hydrolysis of GTP that is bound to Arf proteins. The best-studied role of Arf GAPs is in intracellular traffic. In this review, we will focus mainly on the Arf GAPs that play a role in vesicle formation, Arf GAP1, Arf GAP2 and Arf GAP3 and their yeast homologues, Gcs1p and Glo3p. We discuss the roles of Arf GAPs as regulators and effectors for Arf GTP-binding proteins.
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Affiliation(s)
- Anne Spang
- University of Basel, Growth and Development, Biozentrum, Switzerland.
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48
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Whitney TJ, Gardner DG, Mott ML, Brandon M. Identifying the molecular basis of functions in the transcriptome of the social amoeba Dictyostelium discoideum. GENETICS AND MOLECULAR RESEARCH 2010; 9:394-415. [PMID: 20309825 DOI: 10.4238/vol9-1gmr752] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The unusual life cycle of Dictyostelium discoideum, in which an extra-cellular stressor such as starvation induces the development of a multicellular fruiting body consisting of stalk cells and spores from a culture of identical amoebae, provides an excellent model for investigating the molecular control of differentiation and the transition from single- to multi-cellular life, a key transition in development. We utilized serial analysis of gene expression (SAGE), a molecular method that is unbiased by dependence on previously identified genes, to obtain a transcriptome from a high-density culture of amoebae, in order to examine the transition to multi-cellular development. The SAGE method provides relative expression levels, which allows us to rank order the expressed genes. We found that a large number of ribosomal proteins were expressed at high levels, while various components of the proteosome were expressed at low levels. The only identifiable transmembrane signaling system components expressed in amoebae are related to quorum sensing, and their expression levels were relatively low. The most highly expressed gene in the amoeba transcriptome, dutA untranslated RNA, is a molecule with unknown function that may serve as an inhibitor of translation. These results suggest that high-density amoebae have not initiated development, and they also suggest a mechanism by which the transition into the development program is controlled.
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Affiliation(s)
- T J Whitney
- Department of Biological Sciences, Idaho State University, Pocatello, ID, USA
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49
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Rawet M, Levi-Tal S, Szafer-Glusman E, Parnis A, Cassel D. ArfGAP1 interacts with coat proteins through tryptophan-based motifs. Biochem Biophys Res Commun 2010; 394:553-7. [PMID: 20211604 DOI: 10.1016/j.bbrc.2010.03.017] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2010] [Accepted: 03/03/2010] [Indexed: 11/29/2022]
Abstract
The Arf1 GTPase-activating protein ArfGAP1 regulates vesicular traffic through the COPI system. This protein consists of N-terminal catalytic domain, lipid packing sensors (the ALPS motifs) in the central region, and a carboxy part of unknown function. The carboxy part contains several diaromatic sequences that are reminiscent of motifs known to interact with clathrin adaptors. In pull-down experiments using GST-fused peptides from rat ArfGAP1, a peptide containing a (329)WETF sequence interacted strongly with clathrin adaptors AP1 and AP2, whereas a major coatomer-binding determinant was identified within the extreme carboxy terminal peptide ((405)AADEGWDNQNW). Mutagenesis and peptide competition experiments revealed that this determinant is required for coatomer binding to full-length ArfGAP1, and that interaction is mediated through the delta-subunit of the coatomer adaptor-like subcomplex. Evidence for a role of the carboxy motif in ArfGAP1-coatomer interaction in vivo is provided by means of a reporter fusion assay. Our findings point to mechanistic differences between ArfGAP1 and the other ArfGAPs known to function in the COPI system.
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Affiliation(s)
- Moran Rawet
- Department of Biology, Technion-Israel Institute of Technology, Haifa 32000, Israel
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50
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Hsu VW, Yang JS. Mechanisms of COPI vesicle formation. FEBS Lett 2009; 583:3758-63. [PMID: 19854177 PMCID: PMC2788077 DOI: 10.1016/j.febslet.2009.10.056] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2009] [Revised: 10/15/2009] [Accepted: 10/20/2009] [Indexed: 10/20/2022]
Abstract
Coat Protein I (COPI) is one of the most intensely investigated coat complexes. Numerous studies have contributed to a general understanding of how coat proteins act to initiate intracellular vesicular transport. This review highlights key recent findings that have shaped our current understanding of how COPI vesicles are formed.
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Affiliation(s)
- Victor W Hsu
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, Boston, MA 02115, USA.
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