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Poddar S, Chauvin SD, Archer CH, Qian W, Castillo-Badillo JA, Yin X, Disbennett WM, Miner CA, Holley JA, Naismith TV, Stinson WA, Wei X, Ning Y, Fu J, Ochoa TA, Surve N, Zaver SA, Wodzanowski KA, Balka KR, Venkatraman R, Liu C, Rome K, Bailis W, Shiba Y, Cherry S, Shin S, Semenkovich CF, De Nardo D, Yoh S, Roberson EDO, Chanda SK, Kast DJ, Miner JJ. ArfGAP2 promotes STING proton channel activity, cytokine transit, and autoinflammation. Cell 2025; 188:1605-1622.e26. [PMID: 39947179 PMCID: PMC11928284 DOI: 10.1016/j.cell.2025.01.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2024] [Revised: 11/03/2024] [Accepted: 01/17/2025] [Indexed: 02/23/2025]
Abstract
Stimulator of interferon genes (STING) transmits signals downstream of the cytosolic DNA sensor cyclic guanosine monophosphate-AMP synthase (cGAS), leading to transcriptional upregulation of cytokines. However, components of the STING signaling pathway, such as IRF3 and IFNAR1, are not essential for autoinflammatory disease in STING gain-of-function (STING-associated vasculopathy with onset in infancy [SAVI]) mice. Recent discoveries revealed that STING also functions as a proton channel that deacidifies the Golgi apparatus. Because pH impacts Golgi enzyme activity, protein maturation, and trafficking, we hypothesized that STING proton channel activity influences multiple Golgi functions. Here, we show that STING-mediated proton efflux non-transcriptionally regulates Golgi trafficking of protein cargos. This process requires the Golgi-associated protein ArfGAP2, a cell-type-specific dual regulator of STING-mediated proton efflux and signaling. Deletion of ArfGAP2 in hematopoietic and endothelial cells markedly reduces STING-mediated cytokine and chemokine secretion, immune cell activation, and autoinflammatory pathology in SAVI mice. Thus, ArfGAP2 facilitates STING-mediated signaling and cytokine release in hematopoietic cells, significantly contributing to autoinflammatory disease pathogenesis.
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Affiliation(s)
- Subhajit Poddar
- Division of Rheumatology, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Samuel D Chauvin
- Division of Rheumatology, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Christopher H Archer
- Department of Cell Biology and Physiology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Wei Qian
- Department of Medicine, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Jean A Castillo-Badillo
- Department of Cell Biology and Physiology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Xin Yin
- Immunity and Pathogenesis Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA; State Key Laboratory of Veterinary Biotechnology, Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Harbin 150069, China
| | - W Miguel Disbennett
- Division of Rheumatology, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Cathrine A Miner
- Division of Rheumatology, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Joe A Holley
- Division of Rheumatology, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Teresa V Naismith
- Department of Cell Biology and Physiology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - W Alexander Stinson
- Department of Medicine, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Xiaochao Wei
- Department of Medicine, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Yue Ning
- Division of Rheumatology, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Jiayuan Fu
- Division of Rheumatology, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Trini A Ochoa
- Division of Rheumatology, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Nehalee Surve
- Division of Rheumatology, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Shivam A Zaver
- Division of Rheumatology, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Kimberly A Wodzanowski
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Katherine R Balka
- Department of Biochemistry and Molecular Biology, Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Rajan Venkatraman
- Department of Biochemistry and Molecular Biology, Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Canyu Liu
- Division of Rheumatology, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Kelly Rome
- Department of Pathology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Will Bailis
- Department of Pathology, Children's Hospital of Philadelphia, Philadelphia, PA, USA
| | - Yoko Shiba
- Faculty of Science and Engineering, Iwate University, Morioka 020-8551, Japan
| | - Sara Cherry
- Institute for Immunology and Immune Health, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA; Department of Pathology and Laboratory Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Sunny Shin
- Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Clay F Semenkovich
- Department of Medicine, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Dominic De Nardo
- Department of Biochemistry and Molecular Biology, Immunity Program, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia
| | - Sunnie Yoh
- Immunity and Pathogenesis Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Elisha D O Roberson
- Department of Medicine, Washington University School of Medicine, St Louis, MO 63110, USA; Department of Genetics, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Sumit K Chanda
- Immunity and Pathogenesis Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - David J Kast
- Department of Cell Biology and Physiology, Washington University School of Medicine, St Louis, MO 63110, USA.
| | - Jonathan J Miner
- Division of Rheumatology, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA; Department of Medicine, Washington University School of Medicine, St Louis, MO 63110, USA; Department of Microbiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA; Institute for Immunology and Immune Health, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA; Colton Center for Autoimmunity, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA.
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2
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Suzuki K, Okawa Y, Akter S, Ito H, Shiba Y. Arf GTPase-Activating proteins ADAP1 and ARAP1 regulate incorporation of CD63 in multivesicular bodies. Biol Open 2024; 13:bio060338. [PMID: 38682696 PMCID: PMC11103404 DOI: 10.1242/bio.060338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Accepted: 04/22/2024] [Indexed: 05/01/2024] Open
Abstract
Arf GTPase-activating proteins (ArfGAPs) mediate the hydrolysis of GTP bound to ADP-ribosylation factors. ArfGAPs are critical for cargo sorting in the Golgi-to-ER traffic. However, the role of ArfGAPs in sorting into intralumenal vesicles (ILVs) in multivesicular bodies (MVBs) in post-Golgi traffic remains unclear. Exosomes are extracellular vesicles (EVs) of endosomal origin. CD63 is an EV marker. CD63 is enriched ILVs in MVBs of cells. However, the secretion of CD63 positive EVs has not been consistent with the data on CD63 localization in MVBs, and how CD63-containing EVs are formed is yet to be understood. To elucidate the mechanism of CD63 transport to ILVs, we focused on CD63 localization in MVBs and searched for the ArfGAPs involved in CD63 localization. We observed that ADAP1 and ARAP1 depletion inhibited CD63 localization to enlarged endosomes after Rab5Q79L overexpression. We tested epidermal growth factor (EGF) and CD9 localization in MVBs. We observed that ADAP1 and ARAP1 depletion inhibited CD9 localization in enlarged endosomes but not EGF. Our results indicate ADAP1 and ARAP1, regulate incorporation of CD63 and CD9, but not EGF, in overlapped and different MVBs. Our work will contribute to distinguish heterogenous ILVs and exosomes by ArfGAPs.
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Affiliation(s)
- Kasumi Suzuki
- Graduate course of Biological Sciences, Division of Science and Engineering, Graduate School of Arts and Sciences, Iwate University, 020-8551, Morioka, Japan
| | - Yoshitaka Okawa
- Graduate course of Biological Sciences, Division of Science and Engineering, Graduate School of Arts and Sciences, Iwate University, 020-8551, Morioka, Japan
| | - Sharmin Akter
- Graduate course of Biological Sciences, Division of Science and Engineering, Graduate School of Arts and Sciences, Iwate University, 020-8551, Morioka, Japan
| | - Haruki Ito
- Biological Sciences Course, Faculty of Science and Engineering, Iwate University, 020-8551, Morioka, Japan
| | - Yoko Shiba
- Graduate course of Biological Sciences, Division of Science and Engineering, Graduate School of Arts and Sciences, Iwate University, 020-8551, Morioka, Japan
- Biological Sciences Course, Faculty of Science and Engineering, Iwate University, 020-8551, Morioka, Japan
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3
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Feng Z, Liu S, Su M, Song C, Lin C, Zhao F, Li Y, Zeng X, Zhu Y, Hou Y, Ren C, Zhang H, Yi P, Ji Y, Wang C, Li H, Ma M, Luo L, Li L. TANGO6 regulates cell proliferation via COPI vesicle-mediated RPB2 nuclear entry. Nat Commun 2024; 15:2371. [PMID: 38490996 PMCID: PMC10943085 DOI: 10.1038/s41467-024-46720-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 03/01/2024] [Indexed: 03/18/2024] Open
Abstract
Coat protein complex I (COPI) vesicles mediate the retrograde transfer of cargo between Golgi cisternae and from the Golgi to the endoplasmic reticulum (ER). However, their roles in the cell cycle and proliferation are unclear. This study shows that TANGO6 associates with COPI vesicles via two transmembrane domains. The TANGO6 N- and C-terminal cytoplasmic fragments capture RNA polymerase II subunit B (RPB) 2 in the cis-Golgi during the G1 phase. COPI-docked TANGO6 carries RPB2 to the ER and then to the nucleus. Functional disruption of TANGO6 hinders the nuclear entry of RPB2, which accumulates in the cytoplasm, causing cell cycle arrest in the G1 phase. The conditional depletion or overexpression of TANGO6 in mouse hematopoietic stem cells results in compromised or expanded hematopoiesis. Our study results demonstrate that COPI vesicle-associated TANGO6 plays a role in the regulation of cell cycle progression by directing the nuclear transfer of RPB2, making it a potential target for promoting or arresting cell expansion.
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Affiliation(s)
- Zhi Feng
- Research center of Stem cells and Ageing, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, PR China
| | - Shengnan Liu
- Institute of Developmental Biology and Regenerative Medicine, Key Laboratory of Freshwater Fish Reproduction and Development, Ministry of Education, Southwest University, Chongqing, 400715, PR China
| | - Ming Su
- Research center of Stem cells and Ageing, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, PR China
| | - Chunyu Song
- Institute of Developmental Biology and Regenerative Medicine, Key Laboratory of Freshwater Fish Reproduction and Development, Ministry of Education, Southwest University, Chongqing, 400715, PR China
| | - Chenyu Lin
- Institute of Developmental Biology and Regenerative Medicine, Key Laboratory of Freshwater Fish Reproduction and Development, Ministry of Education, Southwest University, Chongqing, 400715, PR China
| | - Fangying Zhao
- Institute of Developmental Biology and Regenerative Medicine, Key Laboratory of Freshwater Fish Reproduction and Development, Ministry of Education, Southwest University, Chongqing, 400715, PR China
| | - Yang Li
- Research center of Stem cells and Ageing, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, PR China
| | - Xianyan Zeng
- Institute of Life Sciences, Laboratory of Developmental Biology, Department of Cell Biology and Genetics, Chongqing Medical University, Chongqing, 400016, PR China
| | - Yong Zhu
- Institute of Life Sciences, Laboratory of Developmental Biology, Department of Cell Biology and Genetics, Chongqing Medical University, Chongqing, 400016, PR China
| | - Yu Hou
- Institute of Life Sciences, Laboratory of Developmental Biology, Department of Cell Biology and Genetics, Chongqing Medical University, Chongqing, 400016, PR China
| | - Chunguang Ren
- Institute of Life Sciences, Laboratory of Developmental Biology, Department of Cell Biology and Genetics, Chongqing Medical University, Chongqing, 400016, PR China
| | - Huan Zhang
- Institute of Life Sciences, Laboratory of Developmental Biology, Department of Cell Biology and Genetics, Chongqing Medical University, Chongqing, 400016, PR China
| | - Ping Yi
- Department of Obstetrics and Gynecology, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, 401120, PR China
| | - Yong Ji
- Key Laboratory of Cardiovascular and Cerebrovascular Medicine; Key Laboratory of Targeted Intervention of Cardiovascular Disease; Collaborative Innovation Center for Cardiovascular Disease Translational Medicine, Nanjing Medical University, Nanjing, 211166, PR China
- National Key Laboratory of Frigid Zone Cardiovascular Diseases (NKLFZCD), Harbin Medical University, Harbin, 150076, Heilongjiang, PR China
| | - Chao Wang
- MOE Key Laboratory for Membraneless Organelles & Cellular Dynamics, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, University of Science and Technology of China, Hefei, 230027, PR China
| | - Hongtao Li
- Institute of Developmental Biology and Regenerative Medicine, Key Laboratory of Freshwater Fish Reproduction and Development, Ministry of Education, Southwest University, Chongqing, 400715, PR China
| | - Ming Ma
- Institute of Developmental Biology and Regenerative Medicine, Key Laboratory of Freshwater Fish Reproduction and Development, Ministry of Education, Southwest University, Chongqing, 400715, PR China
| | - Lingfei Luo
- Institute of Developmental Biology and Regenerative Medicine, Key Laboratory of Freshwater Fish Reproduction and Development, Ministry of Education, Southwest University, Chongqing, 400715, PR China.
| | - Li Li
- Research center of Stem cells and Ageing, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, PR China.
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4
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Zhang N, Zabotina OA. Critical Determinants in ER-Golgi Trafficking of Enzymes Involved in Glycosylation. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11030428. [PMID: 35161411 PMCID: PMC8840164 DOI: 10.3390/plants11030428] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 01/31/2022] [Accepted: 02/01/2022] [Indexed: 05/03/2023]
Abstract
All living cells generate structurally complex and compositionally diverse spectra of glycans and glycoconjugates, critical for organismal evolution, development, functioning, defense, and survival. Glycosyltransferases (GTs) catalyze the glycosylation reaction between activated sugar and acceptor substrate to synthesize a wide variety of glycans. GTs are distributed among more than 130 gene families and are involved in metabolic processes, signal pathways, cell wall polysaccharide biosynthesis, cell development, and growth. Glycosylation mainly takes place in the endoplasmic reticulum (ER) and Golgi, where GTs and glycosidases involved in this process are distributed to different locations of these compartments and sequentially add or cleave various sugars to synthesize the final products of glycosylation. Therefore, delivery of these enzymes to the proper locations, the glycosylation sites, in the cell is essential and involves numerous secretory pathway components. This review presents the current state of knowledge about the mechanisms of protein trafficking between ER and Golgi. It describes what is known about the primary components of protein sorting machinery and trafficking, which are recognition sites on the proteins that are important for their interaction with the critical components of this machinery.
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5
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Watanabe A, Hataida H, Inoue N, Kamon K, Baba K, Sasaki K, Kimura R, Sasaki H, Eura Y, Ni WF, Shibasaki Y, Waguri S, Kokame K, Shiba Y. Arf GTPase-activating proteins SMAP1 and AGFG2 regulate the size of Weibel-Palade bodies and exocytosis of von Willebrand factor. Biol Open 2021; 10:271213. [PMID: 34369554 PMCID: PMC8430232 DOI: 10.1242/bio.058789] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 07/28/2021] [Indexed: 01/22/2023] Open
Abstract
Arf GTPase-Activating proteins (ArfGAPs) mediate the hydrolysis of GTP bound to ADP-ribosylation factors (Arfs), which are critical to form transport intermediates. ArfGAPs have been thought to be negative regulators of Arfs; however, accumulating evidence indicates that ArfGAPs are important for cargo sorting and promote membrane traffic. Weibel-Palade bodies (WPBs) are cigar-shaped secretory granules in endothelial cells that contain von Willebrand factor (vWF) as their main cargo. WPB biogenesis at the Golgi was reported to be regulated by Arf and their regulators, but the role of ArfGAPs has been unknown. In this study, we performed siRNA screening of ArfGAPs to investigate the role of ArfGAPs in the biogenesis of WPBs. We found two ArfGAPs, SMAP1 and AGFG2, to be involved in WPB size and vWF exocytosis, respectively. SMAP1 depletion resulted in small-sized WPBs, and the lysosomal inhibitor leupeptin recovered the size of WPBs. The results indicate that SMAP1 functions in preventing the degradation of cigar-shaped WPBs. On the other hand, AGFG2 downregulation resulted in the inhibition of vWF secretion upon Phorbol 12-myristate 13-acetate (PMA) or histamine stimulation, suggesting that AGFG2 plays a role in vWF exocytosis. Our study revealed unexpected roles of ArfGAPs in vWF transport. Summary: The Arf GTPase-activating proteins SMAP1 and AGFG2 regulate the size of Weibel-Palade bodies and exocytosis of von Willebrand factor.
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Affiliation(s)
- Asano Watanabe
- Faculty of Science and Engineering, Iwate University, Morioka, 020-8551, Japan
| | - Hikari Hataida
- Faculty of Science and Engineering, Iwate University, Morioka, 020-8551, Japan
| | - Naoya Inoue
- Faculty of Science and Engineering, Iwate University, Morioka, 020-8551, Japan
| | - Kosuke Kamon
- Faculty of Science and Engineering, Iwate University, Morioka, 020-8551, Japan
| | - Keigo Baba
- Faculty of Science and Engineering, Iwate University, Morioka, 020-8551, Japan
| | - Kuniaki Sasaki
- Faculty of Science and Engineering, Iwate University, Morioka, 020-8551, Japan
| | - Rika Kimura
- Faculty of Science and Engineering, Iwate University, Morioka, 020-8551, Japan
| | - Honoka Sasaki
- Faculty of Science and Engineering, Iwate University, Morioka, 020-8551, Japan
| | - Yuka Eura
- Department of Molecular Pathogenesis, National Cerebral and Cardiovascular Center, Osaka, 564-8565, Japan
| | - Wei-Fen Ni
- Department of Biotechnology, National Kaohsiung Normal University, Kaohsiung, 80201, Taiwan
| | - Yuji Shibasaki
- Faculty of Science and Engineering, Iwate University, Morioka, 020-8551, Japan
| | - Satoshi Waguri
- Department of Anatomy and Histology, Fukushima Medical University, Fukushima, 960-1295, Japan
| | - Koichi Kokame
- Department of Molecular Pathogenesis, National Cerebral and Cardiovascular Center, Osaka, 564-8565, Japan
| | - Yoko Shiba
- Faculty of Science and Engineering, Iwate University, Morioka, 020-8551, Japan
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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: 0.5] [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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7
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Zhang L, Jin M, Song M, Liu S, Wang T, Guo K, Zhang Y. ARFGAP1 binds to classical swine fever virus NS5A protein and enhances CSFV replication in PK-15 cells. Vet Microbiol 2021; 255:109034. [PMID: 33721634 DOI: 10.1016/j.vetmic.2021.109034] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 03/01/2021] [Indexed: 12/01/2022]
Abstract
Classical swine fever virus (CSFV), an enveloped virus belonging to the genus Pestivirus of the Flaviviridae family, utilizes cell host factors for its own replication. ARFGAP1, GTPase activating protein of ADP-ribosylation factor 1, regulates COP I vesicle formation and function in cells and is involved in the life cycle of several viruses. However, the effect of ARFGAP1 on the infection of CSFV has not been illustrated. Here we showed that inhibition of ARFGAP1 either by QS11 or by lentivirus-mediated silencing repressed CSFV replication. While, subsequent experiments revealed that CSFV production were increased in cells with sufficient ARFGAP1 expression. However, ARFGAP1 was not involved in CSFV binding, entry, access to cell vesicles, and RNA replication during the early stages of infection. Then, we showed that ARFGAP1 interacted with the viral protein of NS5A, measured by immunoprecipitation, GST-pulldown, and confocal microscopy assays. Furthermore, we revealed that ARFGAP1 could alleviated CSFV NS5A-induced endoplasmic reticulum stress (ERS). Altogether, these results demonstrate that ARFGAP1, a NS5A binding protein, is involved in CSFV replication.
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Affiliation(s)
- Liang Zhang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Mingxing Jin
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Mengzhao Song
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Shanchuan Liu
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Tao Wang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, 712100, China
| | - Kangkang Guo
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, 712100, China.
| | - Yanming Zhang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, 712100, China.
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8
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Evans AS, Lennemann NJ, Coyne CB. BPIFB3 interacts with ARFGAP1 and TMED9 to regulate non-canonical autophagy and RNA virus infection. J Cell Sci 2021; 134:jcs251835. [PMID: 33277377 PMCID: PMC7929927 DOI: 10.1242/jcs.251835] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Accepted: 11/23/2020] [Indexed: 11/20/2022] Open
Abstract
Autophagy is a degradative cellular pathway that targets cytoplasmic contents and organelles for turnover by the lysosome. Various autophagy pathways play key roles in the clearance of viral infections, and many families of viruses have developed unique methods for avoiding degradation. Some positive-stranded RNA viruses, such as enteroviruses and flaviviruses, usurp the autophagic pathway to promote their own replication. We previously identified the endoplasmic reticulum (ER)-localized protein BPIFB3 as an important negative regulator of non-canonical autophagy that uniquely impacts the replication of enteroviruses and flaviviruses. Here, we find that many components of the canonical autophagy machinery are not required for BPIFB3 depletion-induced autophagy and identify the host factors that facilitate its role in the replication of enteroviruses and flaviviruses. Using proximity-dependent biotinylation (BioID) followed by mass spectrometry, we identify ARFGAP1 and TMED9 as two cellular components that interact with BPIFB3 to regulate autophagy and viral replication. Importantly, our data demonstrate that non-canonical autophagy in mammalian cells can be controlled outside of the traditional pathway regulators and define the role of two proteins in BPIFB3 depletion mediated non-canonical autophagy.
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Affiliation(s)
- Azia S Evans
- Department of Pediatrics, University of Pittsburgh School of Medicine, 4401 Penn Ave, Pittsburgh, PA 15224, USA
- Center for Microbial Pathogenesis, 4401 Penn Ave, Pittsburgh, PA 15224, USA
| | - Nicholas J Lennemann
- Department of Microbiology, University of Alabama at Birmingham, 845, 19th St S, Birmingham, AL 35222, USA
| | - Carolyn B Coyne
- Department of Pediatrics, University of Pittsburgh School of Medicine, 4401 Penn Ave, Pittsburgh, PA 15224, USA
- Center for Microbial Pathogenesis, 4401 Penn Ave, Pittsburgh, PA 15224, USA
- Richard K. Mellon Institute for Pediatric Research, UPMC Children's Hospital of Pittsburgh, 4401 Penn Ave, Pittsburgh, PA 15224, USA
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9
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El-Darzi N, Mast N, Petrov AM, Pikuleva IA. 2-Hydroxypropyl-β-cyclodextrin reduces retinal cholesterol in wild-type and Cyp27a1 -/- Cyp46a1 -/- mice with deficiency in the oxysterol production. Br J Pharmacol 2020; 178:3220-3234. [PMID: 32698250 DOI: 10.1111/bph.15209] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 07/14/2020] [Accepted: 07/16/2020] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND AND PURPOSE 2-Hydroxypropyl-β-cyclodextrin (HPCD) is an FDA approved vehicle for drug delivery and an efficient cholesterol-lowering agent. HPCD was proposed to lower tissue cholesterol via multiple mechanisms including those mediated by oxysterols. CYP27A1 and CYP46A1 are the major oxysterol-producing enzymes in the retina that convert cholesterol to 27- and 24-hydroxycholesterol, respectively. We investigated whether HPCD treatments affected the retina of wild-type and Cyp27a1-/- Cyp46a1-/- mice that do not produce the major retinal oxysterols. EXPERIMENTAL APPROACH HPCD administration was either by i.p., p.o. or s.c. Delivery to the retina was confirmed by angiography using the fluorescently labelled HPCD. Effects on the levels of retinal sterols, mRNA and proteins were evaluated by GC-MS, qRT-PCR and label-free approach, respectively. KEY RESULTS In both wild-type and Cyp27a1-/- Cyp46a1-/- mice, HPCD crossed the blood-retinal barrier when delivered i.p. and lowered the retinal cholesterol content when administered p.o. and s.c. In both genotypes, oral HPCD treatment affected the expression of cholesterol-related genes as well as the proteins involved in endocytosis, lysosomal function and lipid homeostasis. Mechanistically, liver X receptors and the altered expression of Lipe (hormone-sensitive lipase), Nceh1 (neutral cholesterol ester hydrolase 1) and NLTP (non-specific lipid-transfer protein) could mediate some of the HPCD effects. CONCLUSIONS AND IMPLICATIONS HPCD treatment altered retinal cholesterol homeostasis and is a potential therapeutic approach for the reduction of drusen and subretinal drusenoid deposits, cholesterol-rich lesions and hallmarks of age-related macular degeneration. LINKED ARTICLES This article is part of a themed issue on Oxysterols, Lifelong Health and Therapeutics. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.16/issuetoc.
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Affiliation(s)
- Nicole El-Darzi
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, USA
| | - Natalia Mast
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, USA
| | - Alexey M Petrov
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, USA
| | - Irina A Pikuleva
- Department of Ophthalmology and Visual Sciences, Case Western Reserve University, Cleveland, Ohio, USA
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10
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ALDH7A1 inhibits the intracellular transport pathways during hypoxia and starvation to promote cellular energy homeostasis. Nat Commun 2019; 10:4068. [PMID: 31492851 PMCID: PMC6731274 DOI: 10.1038/s41467-019-11932-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Accepted: 07/27/2019] [Indexed: 12/13/2022] Open
Abstract
The aldehyde dehydrogenase (ALDH) family of metabolic enzymes converts aldehydes to carboxylates. Here, we find that the reductive consequence of ALDH7A1 activity, which generates NADH (nicotinamide adenine dinucleotide, reduced form) from NAD, underlies how ALDH7A1 coordinates a broad inhibition of the intracellular transport pathways. Studying vesicle formation by the Coat Protein I (COPI) complex, we elucidate that NADH generated by ALDH7A1 targets Brefeldin-A ADP-Ribosylated Substrate (BARS) to inhibit COPI vesicle fission. Moreover, defining a physiologic role for the broad transport inhibition exerted by ALDH7A1, we find that it acts to reduce energy consumption during hypoxia and starvation to promote cellular energy homeostasis. These findings advance the understanding of intracellular transport by revealing how the coordination of multiple pathways can be achieved, and also defining circumstances when such coordination is needed, as well as uncovering an unexpected way that NADH acts in cellular energetics. Intracellular vesicle transport can be regulated by Brefeldin‐A ADP‐Ribosylated Substrate (BARS) during vesicle fission. Here, the authors show that NADH generated by aldehyde dehydrogenase 7A1 (ALDH7A1) inhibits intracellular transport by targeting BARS and inhibiting COPI vesicle fission during situations of energy deprivation
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11
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Yang JS, Hsu JW, Park SY, Lee SY, Li J, Bai M, Alves C, Tseng W, Michelet X, Ho IC, Hsu VW. ALDH7A1 inhibits the intracellular transport pathways during hypoxia and starvation to promote cellular energy homeostasis. Nat Commun 2019. [PMID: 31492851 DOI: 10.1038/s41467-019-11932-11930] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/14/2023] Open
Abstract
The aldehyde dehydrogenase (ALDH) family of metabolic enzymes converts aldehydes to carboxylates. Here, we find that the reductive consequence of ALDH7A1 activity, which generates NADH (nicotinamide adenine dinucleotide, reduced form) from NAD, underlies how ALDH7A1 coordinates a broad inhibition of the intracellular transport pathways. Studying vesicle formation by the Coat Protein I (COPI) complex, we elucidate that NADH generated by ALDH7A1 targets Brefeldin-A ADP-Ribosylated Substrate (BARS) to inhibit COPI vesicle fission. Moreover, defining a physiologic role for the broad transport inhibition exerted by ALDH7A1, we find that it acts to reduce energy consumption during hypoxia and starvation to promote cellular energy homeostasis. These findings advance the understanding of intracellular transport by revealing how the coordination of multiple pathways can be achieved, and also defining circumstances when such coordination is needed, as well as uncovering an unexpected way that NADH acts in cellular energetics.
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Affiliation(s)
- Jia-Shu Yang
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, and Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA.
| | - Jia-Wei Hsu
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, and Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA
| | - Seung-Yeol Park
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, and Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk, 37673, Republic of Korea
| | - Stella Y Lee
- Division of Biology, Kansas State University, Manhattan, KS, 66506, USA
| | - Jian Li
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, and Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA
| | - Ming Bai
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, and Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA
| | - Claudia Alves
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, and Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA
| | - William Tseng
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, and Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA
| | - Xavier Michelet
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, and Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA
| | - I-Cheng Ho
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, and Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA
| | - Victor W Hsu
- Division of Rheumatology, Immunology and Allergy, Brigham and Women's Hospital, and Department of Medicine, Harvard Medical School, Boston, MA, 02115, USA.
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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: 169] [Impact Index Per Article: 28.2] [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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Abstract
Mammalian cells have many membranous organelles that require proper composition of proteins and lipids. Cargo sorting is a process required for transporting specific proteins and lipids to appropriate organelles, and if this process is disrupted, organelle function as well as cell function is disrupted. ArfGAP family proteins have been found to be critical for receptor sorting. In this review, we summarize our recent knowledge about the mechanism of cargo sorting that require function of ArfGAPs in promoting the formation of transport vesicles, and discuss the involvement of specific ArfGAPs for the sorting of a variety of receptors, such as MPR, EGFR, TfR, Glut4, TRAIL-R1/DR4, M5-muscarinic receptor, c-KIT, rhodopsin and β1-integrin. Given the importance of many of these receptors to human disease, the studies of ArfGAPs may provide novel therapeutic strategies in addition to providing mechanistic insight of receptor sorting.
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Affiliation(s)
- Yoko Shiba
- Laboratory of Cellular and Molecular Biology, National Cancer Institute, Bethesda, MD20892, USA
| | - Paul A Randazzo
- Laboratory of Cellular and Molecular Biology, National Cancer Institute, Bethesda, MD20892, USA
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14
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Quilty D, Gray F, Summerfeldt N, Cassel D, Melançon P. Arf activation at the Golgi is modulated by feed-forward stimulation of the exchange factor GBF1. J Cell Sci 2013; 127:354-64. [PMID: 24213530 DOI: 10.1242/jcs.130591] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
ADP-ribosylation factors (Arfs) play central roles in the regulation of vesicular trafficking through the Golgi. Arfs are activated at the Golgi membrane by guanine-nucleotide-exchange factors (GEFs) that are recruited from cytosol. Here, we describe a novel mechanism for the regulation of recruitment and activity of the ArfGEF Golgi-specific BFA resistance factor 1 (GBF1). Conditions that alter the cellular Arf-GDP:Arf-GTP ratio result in GBF1 recruitment. This recruitment of GBF1 occurs selectively on cis-Golgi membranes in direct response to increased Arf-GDP. GBF1 recruitment requires Arf-GDP myristoylation-dependent interactions suggesting regulation of a membrane-bound factor. Once recruited, GBF1 causes increased Arf-GTP production at the Golgi, consistent with a feed-forward self-limiting mechanism of Arf activation. This mechanism is proposed to maintain steady-state levels of Arf-GTP at the cis-Golgi during cycles of Arf-dependent trafficking events.
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Affiliation(s)
- Douglas Quilty
- Department of Cell Biology, University of Alberta, Edmonton, AB T6G 2H7, Canada
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15
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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: 1.4] [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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16
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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: 2.4] [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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17
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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: 1.0] [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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