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Jiang F, Xu Y, Jiang Z, Hu B, Lv Q, Wang Z. Deciphering the immunological and prognostic features of hepatocellular carcinoma through ADP-ribosylation-related genes analysis and identify potential therapeutic target ARFIP2. Cell Signal 2024; 117:111073. [PMID: 38302034 DOI: 10.1016/j.cellsig.2024.111073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Revised: 01/22/2024] [Accepted: 01/29/2024] [Indexed: 02/03/2024]
Abstract
BACKGROUND Hepatocellular carcinoma is one of the most common malignancies, and its prognosis and treatment outcome cannot be accurately predicted. ADP-ribosylation (ADPR) is a post-translationa modification of proteins involved in protein trafficking and immune response. Therefore, it is necessary to explore the ADPR-related genes associated with the prognosis and therapeutic efficacy of hepatocellular carcinoma treatments. METHODS We downloaded the data of hepatocellular carcinoma samples to identify ADPR-related genes as prognostic markers, and established a novel ADPR-related index (ADPRI) based on univariate and multivariate COX regression analyses. Patients' prognosis, clinical features, somatic variant, tumor immune microenvironment, chemotherapeutic response and immunotherapeutic response were systematically analyzed. Finally, the role of ARFIP2 in hepatocellular carcinoma cells was preliminarily explored in vitro. RESULTS The ADPRI consisting of four ADPR related genes (ARL8B, ARFIP2, PARP12, ADPRHL1) was established to be a reliable predictor of survival in patients with hepatocellular carcinoma and was validated using external datasets. Compared with the low ADPRI group, the high ADPRI group presented higher levels of mutation frequency, immune infiltration and patients in high ADPRI group benefit more from immune checkpoint inhibitor treatment. In addition, we predicted some natural small molecule drugs as potential therapeutic targets for hepatocellular carcinoma. Finally, Knockdown of ARFIP2 inhibits the proliferation and migration of hepatocellular carcinoma cells by inducing the G1/S phase cell cycle arrest in HCC cells. CONCLUSIONS The ADPRI can be used to accurately predict the prognosis and immunotherapeutic response of hepatocellular carcinoma patients and providing valuable insights for future precision treatment of patients with hepatocellular carcinoma.
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Affiliation(s)
- Fenfen Jiang
- Laboratory of Hepatobiliary and Pancreas Surgery, Affiliated Hospital of Guilin Medical University, Guilin 541004, Guangxi, China
| | - Yan Xu
- Department of Urology, The First Hospital of China Medical University, Shenyang 110001, China
| | - Zhuang Jiang
- Traditional Chinese Medicine department, Shanghai Haijiang Hospital, 200434 Shanghai, China
| | - Bin Hu
- General Department, Shanghai Yangpu District Central Hospital, 200090 Shanghai, China
| | - Qing Lv
- Gastrointestinal surgery, Wuhan Union Hospital, Wuhan 430022, Hubei, China
| | - Zhiyong Wang
- Gastrointestinal surgery, Wuhan Union Hospital, Wuhan 430022, Hubei, China.
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2
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Key molecules of Mucorales for COVID-19-associated mucormycosis: a narrative review. JOURNAL OF BIO-X RESEARCH 2022. [DOI: 10.1097/jbr.0000000000000131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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3
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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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4
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The ADP-ribosylation factor-like small GTPase FgArl1 participates in growth, pathogenicity and DON production in Fusarium graminearum. Fungal Biol 2020; 124:969-980. [PMID: 33059848 DOI: 10.1016/j.funbio.2020.08.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 08/08/2020] [Accepted: 08/20/2020] [Indexed: 01/04/2023]
Abstract
Fusarium graminearum is the main pathogen of Fusarium head blight (FHB) in wheat and related species, which causes serious production decreases and economic losses and produces toxins such as deoxynivalenol (DON), which endangers the health of humans and livestock. Vesicle transport is a basic physiological process required for cell survival in eukaryotes. Many regulators of vesicle transport are reported to be involved in the pathogenicity of fungi. In yeast and mammalian cells, the ADP-ribosylation factor-like small GTPase Arl1 and its orthologs are involved in regulating vesicular trafficking, cytoskeletal reorganization and other significant biological processes. However, the role of Arl1 in F. graminearum is not well understood. In this study, we characterized the Arl1-homologous protein FgArl1 in F. graminearum and showed that FgArl1 is located in the trans-Golgi apparatus. The deletion of FgARL1 resulted in a significant decrease in vegetative growth and pathogenicity. Further analyses of the ΔFgarl1 mutant revealed defects in the production of DON. Taken together, these results indicate that FgArl1 is important in the development and pathogenicity of F. graminearum.
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5
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De Tito S, Hervás JH, van Vliet AR, Tooze SA. The Golgi as an Assembly Line to the Autophagosome. Trends Biochem Sci 2020; 45:484-496. [PMID: 32307224 DOI: 10.1016/j.tibs.2020.03.010] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 03/05/2020] [Accepted: 03/17/2020] [Indexed: 12/11/2022]
Abstract
Autophagy is traditionally depicted as a signaling cascade that culminates in the formation of an autophagosome that degrades cellular cargo. However, recent studies have identified myriad pathways and cellular organelles underlying the autophagy process, be it as signaling platforms or through the contribution of proteins and lipids. The Golgi complex is recognized as being a central transport hub in the cell, with a critical role in endocytic trafficking and endoplasmic reticulum (ER) to plasma membrane (PM) transport. However, the Golgi is also an important site of key autophagy regulators, including the protein autophagy-related (ATG)-9A and the lipid, phosphatidylinositol-4-phosphate [PI(4)P]. In this review, we highlight the central function of this organelle in autophagy as a transport hub supplying various components of autophagosome formation.
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Affiliation(s)
- Stefano De Tito
- The Molecular Cell Biology of Autophagy, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Javier H Hervás
- The Molecular Cell Biology of Autophagy, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK; Instituto Biofisika (CSIC, UPV/EHU), Departamento de Bioquímica y Biología Molecular, Universidad del País Vasco, Bilbao, Spain
| | - Alexander R van Vliet
- The Molecular Cell Biology of Autophagy, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK
| | - Sharon A Tooze
- The Molecular Cell Biology of Autophagy, The Francis Crick Institute, 1 Midland Road, London NW1 1AT, UK.
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6
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Judith D, Jefferies HBJ, Boeing S, Frith D, Snijders AP, Tooze SA. ATG9A shapes the forming autophagosome through Arfaptin 2 and phosphatidylinositol 4-kinase IIIβ. J Cell Biol 2019; 218:1634-1652. [PMID: 30917996 PMCID: PMC6504893 DOI: 10.1083/jcb.201901115] [Citation(s) in RCA: 127] [Impact Index Per Article: 25.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 02/28/2019] [Accepted: 03/14/2019] [Indexed: 12/24/2022] Open
Abstract
ATG9A is a multispanning membrane protein essential for autophagy. Normally resident in Golgi membranes and endosomes, during amino acid starvation, ATG9A traffics to sites of autophagosome formation. ATG9A is not incorporated into autophagosomes but is proposed to supply so-far-unidentified proteins and lipids to the autophagosome. To address this function of ATG9A, a quantitative analysis of ATG9A-positive compartments immunoisolated from amino acid-starved cells was performed. These ATG9A vesicles are depleted of Golgi proteins and enriched in BAR-domain containing proteins, Arfaptins, and phosphoinositide-metabolizing enzymes. Arfaptin2 regulates the starvation-dependent distribution of ATG9A vesicles, and these ATG9A vesicles deliver the PI4-kinase, PI4KIIIβ, to the autophagosome initiation site. PI4KIIIβ interacts with ATG9A and ATG13 to control PI4P production at the initiation membrane site and the autophagic response. PI4KIIIβ and PI4P likely function by recruiting the ULK1/2 initiation kinase complex subunit ATG13 to nascent autophagosomes.
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Affiliation(s)
- Delphine Judith
- Molecular Cell Biology of Autophagy, The Francis Crick Institute, London, UK
| | | | - Stefan Boeing
- Bioinformatics and Biostatistics, The Francis Crick Institute, London, UK
| | - David Frith
- Proteomics, The Francis Crick Institute, London, UK
| | | | - Sharon A Tooze
- Molecular Cell Biology of Autophagy, The Francis Crick Institute, London, UK
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7
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Zhang Y, Zhang Q, Gui L, Cai Y, Deng X, Li C, Guo Q, He X, Huang J. Let-7e inhibits TNF-α expression by targeting the methyl transferase EZH2 in DENV2-infected THP-1 cells. J Cell Physiol 2018; 233:8605-8616. [PMID: 29768655 DOI: 10.1002/jcp.26576] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2017] [Accepted: 02/26/2018] [Indexed: 12/25/2022]
Abstract
Tumor necrosis factor α (TNFα), an important inflammatory cytokine, is associated with dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS), a severe pathological manifestation of dengue virus (DENV) infection. However, the regulatory mechanism of microRNA on TNFα is currently unknown. Our study showed that the TNFα expression increased immediately and then later decreased, while a marked increase for the miRNA let-7e was detected in dengue virus type 2 (DENV2)-infected peripheral blood mononuclear cells (PBMCs). From this study, we found that let-7e was able to inhibit TNFα expression, but bioinformatics analysis showed that the enhancer of zeste homolog 2 (EZH2) was the potential direct target of let-7e instead of TNFα. EZH2 methyl transferase can produce H3K27me3 and has a negative regulatory role. Using a dual-luciferase reporter assay and Western blotting, we confirmed that EZH2 was a direct target of let-7e and found that siEZH2 could inhibit TNFα expression. In the further study of the regulatory mechanism of EZH2 on TNFα expression, we showed that siEZH2 promoted EZH1 and H3K4me3 expression and inhibited H3K27me3 expression. More importantly, we revealed that siEZH2 down-regulated NF-κB p65 within the nucleus. These findings indicate that the let-7e/EZH2/H3K27me3/NF-κB p65 pathway is a novel regulatory axis of TNFα expression. In addition, we determined the protein differences between siEZH2 and siEZH2-NC by iTRAQ and found a number of proteins that might be associated with TNFα.
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Affiliation(s)
- Yingke Zhang
- Guangdong Provincial Key Laboratory of Organ Donation and Transplant Immunology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.,Guangdong Provincial International Cooperation Base of Science and Technology (Organ Transplantation), The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.,Organ Transplant Center, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.,Institute of Immunology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Qianqian Zhang
- Guangdong Provincial Key Laboratory of Organ Donation and Transplant Immunology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.,Guangdong Provincial International Cooperation Base of Science and Technology (Organ Transplantation), The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.,Organ Transplant Center, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.,Institute of Immunology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Lian Gui
- Guangdong Provincial Key Laboratory of Organ Donation and Transplant Immunology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.,Guangdong Provincial International Cooperation Base of Science and Technology (Organ Transplantation), The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.,Organ Transplant Center, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.,Institute of Immunology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Yan Cai
- Guangdong Provincial Key Laboratory of Organ Donation and Transplant Immunology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.,Guangdong Provincial International Cooperation Base of Science and Technology (Organ Transplantation), The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.,Organ Transplant Center, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Xiaohong Deng
- Guangdong Provincial Key Laboratory of Organ Donation and Transplant Immunology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.,Guangdong Provincial International Cooperation Base of Science and Technology (Organ Transplantation), The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.,Organ Transplant Center, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Cheukfai Li
- Guangdong Provincial Key Laboratory of Organ Donation and Transplant Immunology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.,Guangdong Provincial International Cooperation Base of Science and Technology (Organ Transplantation), The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.,Organ Transplant Center, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Qi Guo
- Institute of Immunology, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Xiaoshun He
- Guangdong Provincial Key Laboratory of Organ Donation and Transplant Immunology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.,Guangdong Provincial International Cooperation Base of Science and Technology (Organ Transplantation), The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.,Organ Transplant Center, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
| | - Junqi Huang
- Guangdong Provincial Key Laboratory of Organ Donation and Transplant Immunology, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.,Guangdong Provincial International Cooperation Base of Science and Technology (Organ Transplantation), The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China.,Organ Transplant Center, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong, China
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8
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Spatiotemporal Control of Lipid Conversion, Actin-Based Mechanical Forces, and Curvature Sensors during Clathrin/AP-1-Coated Vesicle Biogenesis. Cell Rep 2018; 20:2087-2099. [PMID: 28854360 DOI: 10.1016/j.celrep.2017.08.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 06/29/2017] [Accepted: 07/31/2017] [Indexed: 01/03/2023] Open
Abstract
Clathrin/adaptor protein-1-coated carriers connect the secretory and the endocytic pathways. Carrier biogenesis relies on distinct protein networks changing membrane shape at the trans-Golgi network, each regulating coat assembly, F-actin-based mechanical forces, or the biophysical properties of lipid bilayers. How these different hubs are spatiotemporally coordinated remains largely unknown. Using in vitro reconstitution systems, quantitative proteomics, and lipidomics, as well as in vivo cell-based assays, we characterize the protein networks controlling membrane lipid composition, membrane shape, and carrier scission. These include PIP5K1A and phospholipase C-beta 3 controlling the conversion of PI[4]P into diacylglycerol. PIP5K1A binding to RAC1 provides a link to F-actin-based mechanical forces needed to tubulate membranes. Tubular membranes then recruit the BAR-domain-containing arfaptin-1/2 guiding carrier scission. These findings provide a framework for synchronizing the chemical/biophysical properties of lipid bilayers, F-actin-based mechanical forces, and the activity of proteins sensing membrane shape during clathrin/adaptor protein-1-coated carrier biogenesis.
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9
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Membrane re-modelling by BAR domain superfamily proteins via molecular and non-molecular factors. Biochem Soc Trans 2018. [PMID: 29540508 DOI: 10.1042/bst20170322] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Lipid membranes are structural components of cell surfaces and intracellular organelles. Alterations in lipid membrane shape are accompanied by numerous cellular functions, including endocytosis, intracellular transport, and cell migration. Proteins containing Bin-Amphiphysin-Rvs (BAR) domains (BAR proteins) are unique, because their structures correspond to the membrane curvature, that is, the shape of the lipid membrane. BAR proteins present at high concentration determine the shape of the membrane, because BAR domain oligomers function as scaffolds that mould the membrane. BAR proteins co-operate with various molecular and non-molecular factors. The molecular factors include cytoskeletal proteins such as the regulators of actin filaments and the membrane scission protein dynamin. Lipid composition, including saturated or unsaturated fatty acid tails of phospholipids, also affects the ability of BAR proteins to mould the membrane. Non-molecular factors include the external physical forces applied to the membrane, such as tension and friction. In this mini-review, we will discuss how the BAR proteins orchestrate membrane dynamics together with various molecular and non-molecular factors.
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10
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Abstract
ADP-ribosylation factors (Arfs) and ADP-ribosylation factor-like proteins (Arls) are highly conserved small GTPases that function as main regulators of vesicular trafficking and cytoskeletal reorganization. Arl1, the first identified member of the large Arl family, is an important regulator of Golgi complex structure and function in organisms ranging from yeast to mammals. Together with its effectors, Arl1 has been shown to be involved in several cellular processes, including endosomal trans-Golgi network and secretory trafficking, lipid droplet and salivary granule formation, innate immunity and neuronal development, stress tolerance, as well as the response of the unfolded protein. In this Commentary, we provide a comprehensive summary of the Arl1-dependent cellular functions and a detailed characterization of several Arl1 effectors. We propose that involvement of Arl1 in these diverse cellular functions reflects the fact that Arl1 is activated at several late-Golgi sites, corresponding to specific molecular complexes that respond to and integrate multiple signals. We also provide insight into how the GTP-GDP cycle of Arl1 is regulated, and highlight a newly discovered mechanism that controls the sophisticated regulation of Arl1 activity at the Golgi complex.
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Affiliation(s)
- Chia-Jung Yu
- Department of Cell and Molecular Biology, College of Medicine, Chang Gung University, Linkou, Tao-Yuan 33302, Taiwan.,Department of Thoracic Medicine, Chang Gung Memorial Hospital, Linkou, Tao-Yuan 33305, Taiwan
| | - Fang-Jen S Lee
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei 10002, Taiwan .,Department of Medical Research, National Taiwan University Hospital, Taipei 10002, Taiwan
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11
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Starheim KK, Kalvik TV, Bjørkøy G, Arnesen T. Depletion of the human N-terminal acetyltransferase hNaa30 disrupts Golgi integrity and ARFRP1 localization. Biosci Rep 2017; 37:BSR20170066. [PMID: 28356483 PMCID: PMC5408665 DOI: 10.1042/bsr20170066] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Revised: 03/16/2017] [Accepted: 03/28/2017] [Indexed: 01/01/2023] Open
Abstract
The organization of the Golgi apparatus (GA) is tightly regulated. Golgi stack scattering is observed in cellular processes such as apoptosis and mitosis, and has also been associated with disruption of cellular lipid metabolism and neurodegenerative diseases. Our studies show that depletion of the human N-α-acetyltransferase 30 (hNaa30) induces fragmentation of the Golgi stack in HeLa and CAL-62 cell lines. The GA associated GTPase ADP ribosylation factor related protein 1 (ARFRP1) was previously shown to require N-terminal acetylation for membrane association and based on its N-terminal sequence, it is likely to be a substrate of hNaa30. ARFRP1 is involved in endosome-to-trans-Golgi network (TGN) traffic. We observed that ARFRP1 shifted from a predominantly cis-Golgi and TGN localization to localizing both Golgi and non-Golgi vesicular structures in hNaa30-depleted cells. However, we did not observe loss of membrane association of ARFRP1. We conclude that hNaa30 depletion induces Golgi scattering and induces aberrant ARFRP1 Golgi localization.
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Affiliation(s)
- Kristian K Starheim
- Department of Molecular Biology, University of Bergen, N-5020 Bergen, Norway
- Department of Molecular Medicine and Cancer Research, Center of Molecular Inflammation Research, Norwegian University of Technology and Natural Sciences, N-7006 Trondheim, Norway
| | - Thomas V Kalvik
- Department of Molecular Biology, University of Bergen, N-5020 Bergen, Norway
| | - Geir Bjørkøy
- Department of Molecular Medicine and Cancer Research, Center of Molecular Inflammation Research, Norwegian University of Technology and Natural Sciences, N-7006 Trondheim, Norway
| | - Thomas Arnesen
- Department of Molecular Biology, University of Bergen, N-5020 Bergen, Norway
- Department of Surgery, Haukeland University Hospital, N-5021 Bergen, Norway
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12
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Salzer U, Kostan J, Djinović-Carugo K. Deciphering the BAR code of membrane modulators. Cell Mol Life Sci 2017; 74:2413-2438. [PMID: 28243699 PMCID: PMC5487894 DOI: 10.1007/s00018-017-2478-0] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Revised: 01/25/2017] [Accepted: 01/27/2017] [Indexed: 01/06/2023]
Abstract
The BAR domain is the eponymous domain of the “BAR-domain protein superfamily”, a large and diverse set of mostly multi-domain proteins that play eminent roles at the membrane cytoskeleton interface. BAR domain homodimers are the functional units that peripherally associate with lipid membranes and are involved in membrane sculpting activities. Differences in their intrinsic curvatures and lipid-binding properties account for a large variety in membrane modulating properties. Membrane activities of BAR domains are further modified and regulated by intramolecular or inter-subunit domains, by intermolecular protein interactions, and by posttranslational modifications. Rather than providing detailed cell biological information on single members of this superfamily, this review focuses on biochemical, biophysical, and structural aspects and on recent findings that paradigmatically promote our understanding of processes driven and modulated by BAR domains.
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Affiliation(s)
- Ulrich Salzer
- Max F. Perutz Laboratories, Department of Medical Biochemistry, Medical University of Vienna, Dr. Bohr-Gasse 9, 1030, Vienna, Austria
| | - Julius Kostan
- Max F. Perutz Laboratories, Department of Structural and Computational Biology, University of Vienna, Campus Vienna Biocenter 5, 1030, Vienna, Austria
| | - Kristina Djinović-Carugo
- Max F. Perutz Laboratories, Department of Structural and Computational Biology, University of Vienna, Campus Vienna Biocenter 5, 1030, Vienna, Austria.
- Department of Biochemistry, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Večna pot 119, 1000, Ljubljana, Slovenia.
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13
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BAR Domain-Containing FAM92 Proteins Interact with Chibby1 To Facilitate Ciliogenesis. Mol Cell Biol 2016; 36:2668-2680. [PMID: 27528616 DOI: 10.1128/mcb.00160-16] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 08/05/2016] [Indexed: 02/03/2023] Open
Abstract
Chibby1 (Cby1) is a small, conserved coiled-coil protein that localizes to centrioles/basal bodies and plays a crucial role in the formation and function of cilia. During early stages of ciliogenesis, Cby1 is required for the efficient recruitment of small vesicles at the distal end of centrioles to facilitate basal body docking to the plasma membrane. Here, we identified family with sequence similarity 92, member A (FAM92A) and FAM92B, which harbor predicted lipid-binding BAR domains, as novel Cby1-interacting partners using tandem affinity purification and mass spectrometry. We found that in cultured cell lines, FAM92A colocalizes with Cby1 at the centrioles/basal bodies of primary cilia, while FAM92B is undetectable. In airway multiciliated cells, both FAM92A and -92B colocalize with Cby1 at the base of cilia. Notably, the centriolar localization of FAM92A and -92B depends largely on Cby1. Knockdown of FAM92A in RPE1 cells impairs ciliogenesis. Consistent with the membrane-remodeling properties of BAR domains, FAM92A and -92B in cooperation with Cby1 induce deformed membrane-like structures containing the small GTPase Rab8 in cultured cells. Our results therefore suggest that FAM92 proteins interact with Cby1 to promote ciliogenesis via regulation of membrane-remodeling processes.
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14
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Tanaka Y, Ono N, Shima T, Tanaka G, Katoh Y, Nakayama K, Takatsu H, Shin HW. The phospholipid flippase ATP9A is required for the recycling pathway from the endosomes to the plasma membrane. Mol Biol Cell 2016; 27:3883-3893. [PMID: 27733620 PMCID: PMC5170610 DOI: 10.1091/mbc.e16-08-0586] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2016] [Revised: 09/30/2016] [Accepted: 10/04/2016] [Indexed: 12/20/2022] Open
Abstract
ATP9A is localized to phosphatidylserine-positive early and recycling endosomes, but not late endosomes, in HeLa cells. ATP9A plays a crucial role in recycling of transferrin and glucose transporter 1 from endosomes to the plasma membrane. Type IV P-type ATPases (P4-ATPases) are phospholipid flippases that translocate phospholipids from the exoplasmic (or luminal) to the cytoplasmic leaflet of lipid bilayers. In Saccharomyces cerevisiae, P4-ATPases are localized to specific subcellular compartments and play roles in compartment-mediated membrane trafficking; however, roles of mammalian P4-ATPases in membrane trafficking are poorly understood. We previously reported that ATP9A, one of 14 human P4-ATPases, is localized to endosomal compartments and the Golgi complex. In this study, we found that ATP9A is localized to phosphatidylserine (PS)-positive early and recycling endosomes, but not late endosomes, in HeLa cells. Depletion of ATP9A delayed the recycling of transferrin from endosomes to the plasma membrane, although it did not affect the morphology of endosomal structures. Moreover, depletion of ATP9A caused accumulation of glucose transporter 1 in endosomes, probably by inhibiting their recycling. By contrast, depletion of ATP9A affected neither the early/late endosomal transport and degradation of epidermal growth factor (EGF) nor the transport of Shiga toxin B fragment from early/recycling endosomes to the Golgi complex. Therefore ATP9A plays a crucial role in recycling from endosomes to the plasma membrane.
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Affiliation(s)
- Yoshiki Tanaka
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Natsuki Ono
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Takahiro Shima
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Gaku Tanaka
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Yohei Katoh
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Kazuhisa Nakayama
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Hiroyuki Takatsu
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
| | - Hye-Won Shin
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan
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15
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Galindo A, Soler N, McLaughlin SH, Yu M, Williams RL, Munro S. Structural Insights into Arl1-Mediated Targeting of the Arf-GEF BIG1 to the trans-Golgi. Cell Rep 2016; 16:839-50. [PMID: 27373159 PMCID: PMC4956616 DOI: 10.1016/j.celrep.2016.06.022] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 05/09/2016] [Accepted: 06/02/2016] [Indexed: 11/28/2022] Open
Abstract
The GTPase Arf1 is the major regulator of vesicle traffic at both the cis- and trans-Golgi. Arf1 is activated at the cis-Golgi by the guanine nucleotide exchange factor (GEF) GBF1 and at the trans-Golgi by the related GEF BIG1 or its paralog, BIG2. The trans-Golgi-specific targeting of BIG1 and BIG2 depends on the Arf-like GTPase Arl1. We find that Arl1 binds to the dimerization and cyclophilin binding (DCB) domain in BIG1 and report a crystal structure of human Arl1 bound to this domain. Residues in the DCB domain that bind Arl1 are required for BIG1 to locate to the Golgi in vivo. DCB domain-binding residues in Arl1 have a distinct conformation from those in known Arl1-effector complexes, and this plasticity allows Arl1 to interact with different effectors of unrelated structure. The findings provide structural insight into how Arf1 GEFs, and hence active Arf1, achieve their correct subcellular distribution.
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Affiliation(s)
- Antonio Galindo
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Nicolas Soler
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Stephen H McLaughlin
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Minmin Yu
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Roger L Williams
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | - Sean Munro
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK.
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16
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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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17
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Eiseler T, Wille C, Koehler C, Illing A, Seufferlein T. Protein Kinase D2 Assembles a Multiprotein Complex at the Trans-Golgi Network to Regulate Matrix Metalloproteinase Secretion. J Biol Chem 2015; 291:462-77. [PMID: 26507660 DOI: 10.1074/jbc.m115.673582] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Indexed: 11/06/2022] Open
Abstract
Vesicle formation and fission are tightly regulated at the trans-Golgi network (TGN) during constitutive secretion. Two major protein families regulate these processes: members of the adenosyl-ribosylation factor family of small G-proteins (ARFs) and the protein kinase D (PKD) family of serine/threonine kinases. The functional relationship between these two key regulators of protein transport from the TGN so far is elusive. We here demonstrate the assembly of a novel functional protein complex at the TGN and its key members: cytosolic PKD2 binds ARF-like GTPase (ARL1) and shuttles ARL1 to the TGN. ARL1, in turn, localizes Arfaptin2 to the TGN. At the TGN, where PKD2 interacts with active ARF1, PKD2, and ARL1 are required for the assembly of a complex comprising of ARF1 and Arfaptin2 leading to secretion of matrix metalloproteinase-2 and -7. In conclusion, our data indicate that PKD2 is a core factor in the formation of this multiprotein complex at the TGN that controls constitutive secretion of matrix metalloproteinase cargo.
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Affiliation(s)
- Tim Eiseler
- From the Department of Internal Medicine I, Ulm University, Albert Einstein Allee 23, D-89081 Ulm, Germany and
| | - Christoph Wille
- From the Department of Internal Medicine I, Ulm University, Albert Einstein Allee 23, D-89081 Ulm, Germany and
| | - Conny Koehler
- the Department of Internal Medicine I, Martin-Luther University Halle-Wittenberg, Ernst-Grube, Strasse 40, D-06120 Halle (Saale), Germany
| | - Anett Illing
- From the Department of Internal Medicine I, Ulm University, Albert Einstein Allee 23, D-89081 Ulm, Germany and
| | - Thomas Seufferlein
- From the Department of Internal Medicine I, Ulm University, Albert Einstein Allee 23, D-89081 Ulm, Germany and
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18
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Chang L, Kreko-Pierce T, Eaton BA. The guanine exchange factor Gartenzwerg and the small GTPase Arl1 function in the same pathway with Arfaptin during synapse growth. Biol Open 2015; 4:947-53. [PMID: 26116655 PMCID: PMC4542281 DOI: 10.1242/bio.011262] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
The generation of neuronal morphology requires transport vesicles originating from the Golgi apparatus (GA) to deliver specialized components to the axon and dendrites. Drosophila Arfaptin is a membrane-binding protein localized to the GA that is required for the growth of the presynaptic nerve terminal. Here we provide biochemical, cellular and genetic evidence that the small GTPase Arl1 and the guanine-nucleotide exchange factor (GEF) Gartenzwerg are required for Arfaptin function at the Golgi during synapse growth. Our data define a new signaling pathway composed of Arfaptin, Arl1, and Garz, required for the generation of normal synapse morphology.
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Affiliation(s)
- Leo Chang
- Department of Physiology, Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - Tabita Kreko-Pierce
- Department of Physiology, Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
| | - Benjamin A Eaton
- Department of Physiology, Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
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19
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Huang LH, Lee WC, You ST, Cheng CC, Yu CJ. Arfaptin-1 negatively regulates Arl1-mediated retrograde transport. PLoS One 2015; 10:e0118743. [PMID: 25789876 PMCID: PMC4366199 DOI: 10.1371/journal.pone.0118743] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 01/11/2015] [Indexed: 12/24/2022] Open
Abstract
The small GTPase Arf-like protein 1 (Arl1) is well known for its role in intracellular vesicular transport at the trans-Golgi network (TGN). In this study, we used differential affinity chromatography combined with mass spectrometry to identify Arf-interacting protein 1b (arfaptin-1b) as an Arl1-interacting protein and characterized a novel function for arfaptin-1 (including the arfaptin-1a and 1b isoforms) in Arl1-mediated retrograde transport. Using a Shiga-toxin subunit B (STxB) transportation assay, we demonstrated that knockdown of arfaptin-1 accelerated the retrograde transport of STxB from the endosome to the Golgi apparatus, whereas Arl1 knockdown inhibited STxB transport compared with control cells. Arfaptin-1 overexpression, but not an Arl1 binding-defective mutant (arfaptin-1b-F317A), consistently inhibited STxB transport. Exogenous arfaptin-1 expression did not interfere with the localization of the Arl1-interacting proteins golgin-97 and golgin-245 to the TGN and vice versa. Moreover, we found that the N-terminal region of arfaptin-1 was involved in the regulation of retrograde transport. Our results show that arfaptin-1 acts as a negative regulator in Arl1-mediated retrograde transport and suggest that different functional complexes containing Arl1 form in distinct microdomains and are responsible for different functions.
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Affiliation(s)
- Lien-Hung Huang
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan
| | - Wei-Chung Lee
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan
| | - Shu-Ting You
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Chia-Chen Cheng
- Department of Cell and Molecular Biology, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan
| | - Chia-Jung Yu
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan
- Department of Cell and Molecular Biology, College of Medicine, Chang Gung University, Tao-Yuan, Taiwan
- Molecular Medicine Research Center, Chang Gung University, Tao-Yuan, Taiwan
- * E-mail:
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20
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Affiliation(s)
- Yusong Guo
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, California 94720-3200;
| | - Daniel W. Sirkis
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, California 94720-3200;
| | - Randy Schekman
- Department of Molecular and Cell Biology, Howard Hughes Medical Institute, University of California, Berkeley, California 94720-3200;
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21
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LAPTM5 promotes lysosomal degradation of intracellular CD3ζ but not of cell surface CD3ζ. Immunol Cell Biol 2014; 92:527-34. [PMID: 24638062 DOI: 10.1038/icb.2014.18] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2013] [Revised: 02/04/2014] [Accepted: 02/17/2014] [Indexed: 12/17/2022]
Abstract
The lysosomal protein LAPTM5 has been shown to negatively regulate cell surface T cell receptor (TCR) expression and T-cell activation by promoting CD3ζ degradation in lysosomes, but the mechanism remains largely unknown. Here we show that LAPTM5 promotes lysosomal translocation of intracellular CD3ζ but not of the cell surface CD3ζ associated with the mature TCR complex. Kinetic analysis of the subcellular localization of the newly synthesized CD3ζ suggests that LAPTM5 targets CD3ζ in the Golgi apparatus and promotes its lysosomal translocation. Consistently, a Golgi-localizing mutant CD3ζ can be transported to and degraded in the lysosome by LAPTM5. A CD3ζ YF mutant in which all six tyrosine residues in the immunoreceptor tyrosine-based activation motif are mutated to phenylalanines is degraded as efficiently as is wild type CD3ζ, further suggesting that TCR signaling-triggered tyrosine phosphorylation of CD3ζ is dispensable for LAPTM5-mediated degradation. Previously, Src-like adapter protein (SLAP) and E3 ubiquitin ligase c-Cbl have been shown to mediate the ubiquitination of CD3ζ in the internalized TCR complex and its subsequent lysosomal degradation. We show that LAPTM5 and SLAP/c-Cbl function in distinct genetic pathways to negatively regulate TCR expression. Collectively, these results suggest that CD3ζ can be degraded by two pathways: SLAP/c-Cbl, which targets internalized cell surface CD3ζ dependent on TCR signaling, and LAPTM5, which targets intracellular CD3ζ independent of TCR signaling.
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22
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Torres IL, Rosa-Ferreira C, Munro S. The Arf family G protein Arl1 is required for secretory granule biogenesis in Drosophila. J Cell Sci 2014; 127:2151-60. [PMID: 24610947 DOI: 10.1242/jcs.122028] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The small G protein Arf like 1 (Arl1) is found at the Golgi complex, and its GTP-bound form recruits several effectors to the Golgi including GRIP-domain-containing coiled-coil proteins, and the Arf1 exchange factors Big1 and Big2. To investigate the role of Arl1, we have characterised a loss-of-function mutant of the Drosophila Arl1 orthologue. The gene is essential, and examination of clones of cells lacking Arl1 shows that it is required for recruitment of three of the four GRIP domain golgins to the Golgi, with Drosophila GCC185 being less dependent on Arl1. At a functional level, Arl1 is essential for formation of secretory granules in the larval salivary gland. When Arl1 is missing, Golgi are still present but there is a dispersal of adaptor protein 1 (AP-1), a clathrin adaptor that requires Arf1 for its membrane recruitment and which is known to be required for secretory granule biogenesis. Arl1 does not appear to be required for AP-1 recruitment in all tissues, suggesting that it is crucially required to enhance Arf1 activation at the trans-Golgi in particular tissues.
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Affiliation(s)
- Isabel L Torres
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
| | | | - Sean Munro
- MRC Laboratory of Molecular Biology, Francis Crick Avenue, Cambridge CB2 0QH, UK
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23
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Steeb H, Ramsey JM, Guest PC, Stocki P, Cooper JD, Rahmoune H, Ingudomnukul E, Auyeung B, Ruta L, Baron-Cohen S, Bahn S. Serum proteomic analysis identifies sex-specific differences in lipid metabolism and inflammation profiles in adults diagnosed with Asperger syndrome. Mol Autism 2014; 5:4. [PMID: 24467795 PMCID: PMC3905921 DOI: 10.1186/2040-2392-5-4] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2013] [Accepted: 12/31/2013] [Indexed: 01/02/2023] Open
Abstract
Background The higher prevalence of Asperger Syndrome (AS) and other autism spectrum conditions in males has been known for many years. However, recent multiplex immunoassay profiling studies have shown that males and females with AS have distinct proteomic changes in serum. Methods Here, we analysed sera from adults diagnosed with AS (males = 14, females = 16) and controls (males = 13, females = 16) not on medication at the time of sample collection, using a combination of multiplex immunoassay and shotgun label-free liquid chromatography mass spectrometry (LC-MSE). The main objective was to identify sex-specific serum protein changes associated with AS. Results Multiplex immunoassay profiling led to identification of 16 proteins that were significantly altered in AS individuals in a sex-specific manner. Three of these proteins were altered in females (ADIPO, IgA, APOA1), seven were changed in males (BMP6, CTGF, ICAM1, IL-12p70, IL-16, TF, TNF-alpha) and six were changed in both sexes but in opposite directions (CHGA, EPO, IL-3, TENA, PAP, SHBG). Shotgun LC-MSE profiling led to identification of 13 serum proteins which had significant sex-specific changes in the AS group and, of these, 12 were altered in females (APOC2, APOE, ARMC3, CLC4K, FETUB, GLCE, MRRP1, PTPA, RN149, TLE1, TRIPB, ZC3HE) and one protein was altered in males (RGPD4). The free androgen index in females with AS showed an increased ratio of 1.63 compared to controls. Conclusion Taken together, the serum multiplex immunoassay and shotgun LC-MSE profiling results indicate that adult females with AS had alterations in proteins involved mostly in lipid transport and metabolism pathways, while adult males with AS showed changes predominantly in inflammation signalling. These results provide further evidence that the search for biomarkers or novel drug targets in AS may require stratification into male and female subgroups, and could lead to the development of novel targeted treatment approaches.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Sabine Bahn
- Department of Chemical Engineering & Biotechnology, University of Cambridge, Tennis Court Road, Cambridge, UK.
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24
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Lefebvre M, Tetaud E, Thonnus M, Salin B, Boissier F, Blancard C, Sauvanet C, Metzler C, Espiau B, Sahin A, Merlin G. LdFlabarin, a new BAR domain membrane protein of Leishmania flagellum. PLoS One 2013; 8:e76380. [PMID: 24086735 PMCID: PMC3785460 DOI: 10.1371/journal.pone.0076380] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Accepted: 08/23/2013] [Indexed: 11/18/2022] Open
Abstract
During the Leishmania life cycle, the flagellum undergoes successive assembly and disassembly of hundreds of proteins. Understanding these processes necessitates the study of individual components. Here, we investigated LdFlabarin, an uncharacterized L. donovani flagellar protein. The gene is conserved within the Leishmania genus and orthologous genes only exist in the Trypanosoma genus. LdFlabarin associates with the flagellar plasma membrane, extending from the base to the tip of the flagellum as a helicoidal structure. Site-directed mutagenesis, deletions and chimera constructs showed that LdFlabarin flagellar addressing necessitates three determinants: an N-terminal potential acylation site and a central BAR domain for membrane targeting and the C-terminal domain for flagellar specificity. In vitro, the protein spontaneously associates with liposomes, triggering tubule formation, which suggests a structural/morphogenetic function. LdFlabarin is the first characterized Leishmania BAR domain protein, and the first flagellum-specific BAR domain protein.
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Affiliation(s)
- Michèle Lefebvre
- CNRS UMR 5290, Montpellier, France
- Université Montpellier 1, Montpellier, France
- Centre Hospitalier Universitaire La Colombière, Montpellier, France
- IRD 224, Montpellier, France
| | - Emmanuel Tetaud
- CNRS UMR 5095, Institut de Biochimie Génétique et Cellulaire, Bordeaux, France
- Université Bordeaux Segalen, Bordeaux, France
| | - Magali Thonnus
- CNRS UMR 5234, Bordeaux, France
- Université Bordeaux Segalen, Bordeaux, France
| | - Bénédicte Salin
- CNRS UMR 5095, Institut de Biochimie Génétique et Cellulaire, Bordeaux, France
- Université Bordeaux Segalen, Bordeaux, France
| | - Fanny Boissier
- CNRS UMR 5095, Institut de Biochimie Génétique et Cellulaire, Bordeaux, France
- Université Bordeaux Segalen, Bordeaux, France
| | - Corinne Blancard
- CNRS UMR 5095, Institut de Biochimie Génétique et Cellulaire, Bordeaux, France
- Université Bordeaux Segalen, Bordeaux, France
| | - Cécile Sauvanet
- CNRS UMR 5095, Institut de Biochimie Génétique et Cellulaire, Bordeaux, France
- Université Bordeaux Segalen, Bordeaux, France
| | | | - Benoît Espiau
- CNRS-EPHE USR 3278, Papetoai, Moorea, Polynésie Française
| | - Annelise Sahin
- CNRS UMR 5234, Bordeaux, France
- Université Bordeaux Segalen, Bordeaux, France
| | - Gilles Merlin
- CNRS UMR 5290, Montpellier, France
- Université Montpellier 1, Montpellier, France
- Centre Hospitalier Universitaire La Colombière, Montpellier, France
- IRD 224, Montpellier, France
- * E-mail:
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25
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Abstract
Secretory granule biogenesis is a pivotal process for regulated release of hormones and neurotransmitters. A prominent example is the pancreatic β cell that secretes insulin, a major anabolic hormone controlling cellular metabolism upon nutrient availability. We recently described a checkpoint mechanism that halts scission of nascent secretory granules at the trans-Golgi network (TGN) until complete loading of insulin is achieved. We demonstrated that the Bin/Amphiphysin/Rvs (BAR) domain-containing protein Arfaptin-1 prevents granule scission until it is phosphorylated by Protein Kinase D (PKD). Arfaptin-1 phosphorylation releases its binding to ADP-rybosylation factor (ARF) allowing scission to occur. Lack of this control mechanism in β cells resulted in premature scission, generation of dysfunctional insulin granules and impaired regulated insulin secretion without affecting constitutive release of other transport carriers. Here we discuss two important questions related to this work: How might completion of granule loading be sensed by PKD, and how does Arfaptin-1 specifically regulate insulin granule formation in beta cells?
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Affiliation(s)
- Helmuth Gehart
- IGBMC (Institut de Génétique et de Biologie Moléculaire et Cellulaire); INSERM; CNRS; Université de Strasbourg; Illkirch, France ; Institute of Cell Biology; ETH Zurich; Zurich, Switzerland
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26
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Chang L, Kreko T, Davison H, Cusmano T, Wu Y, Rothenfluh A, Eaton BA. Normal dynactin complex function during synapse growth in Drosophila requires membrane binding by Arfaptin. Mol Biol Cell 2013; 24:1749-64, S1-5. [PMID: 23596322 PMCID: PMC3667727 DOI: 10.1091/mbc.e12-09-0697] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2012] [Revised: 04/04/2013] [Accepted: 04/08/2013] [Indexed: 01/11/2023] Open
Abstract
Mutations in DCTN1, a component of the dynactin complex, are linked to neurodegenerative diseases characterized by a broad collection of neuropathologies. Because of the pleiotropic nature of dynactin complex function within the neuron, defining the causes of neuropathology in DCTN1 mutants has been difficult. We combined a genetic screen with cellular assays of dynactin complex function to identify genes that are critical for dynactin complex function in the nervous system. This approach identified the Drosophila homologue of Arfaptin, a multifunctional protein that has been implicated in membrane trafficking. We find that Arfaptin and the Drosophila DCTN1 homologue, Glued, function in the same pathway during synapse growth but not during axonal transport or synapse stabilization. Arfaptin physically associates with Glued and other dynactin complex components in the nervous system of both flies and mice and colocalizes with Glued at the Golgi in motor neurons. Mechanistically, membrane binding by Arfaptin mediates membrane association of the dynactin complex in motor neurons and is required for normal synapse growth. Arfaptin represents a novel dynactin complex-binding protein that specifies dynactin complex function during synapse growth.
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Affiliation(s)
- Leo Chang
- Department of Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229
| | - Tabita Kreko
- Department of Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229
| | - Holly Davison
- Department of Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229
| | - Tim Cusmano
- Department of Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229
| | - Yimin Wu
- Department of Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229
| | - Adrian Rothenfluh
- Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Benjamin A. Eaton
- Department of Physiology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229
- Barshop Institute for Longevity and Aging Studies, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229
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27
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Cruz-Garcia D, Ortega-Bellido M, Scarpa M, Villeneuve J, Jovic M, Porzner M, Balla T, Seufferlein T, Malhotra V. Recruitment of arfaptins to the trans-Golgi network by PI(4)P and their involvement in cargo export. EMBO J 2013; 32:1717-29. [PMID: 23695357 DOI: 10.1038/emboj.2013.116] [Citation(s) in RCA: 214] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2012] [Accepted: 04/25/2013] [Indexed: 11/09/2022] Open
Abstract
The BAR (Bin/Amphiphysin/Rvs) domain proteins arfaptin1 and arfaptin2 are localized to the trans-Golgi network (TGN) and, by virtue of their ability to sense and/or generate membrane curvature, could play an important role in the biogenesis of transport carriers. We report that arfaptins contain an amphipathic helix (AH) preceding the BAR domain, which is essential for their binding to phosphatidylinositol 4-phosphate (PI(4)P)-containing liposomes and the TGN of mammalian cells. The binding of arfaptin1, but not arfaptin2, to PI(4)P is regulated by protein kinase D (PKD) mediated phosphorylation at Ser100 within the AH. We also found that only arfaptin1 is required for the PKD-dependent trafficking of chromogranin A by the regulated secretory pathway. Altogether, these findings reveal the importance of PI(4)P and PKD in the recruitment of arfaptins at the TGN and their requirement in the events leading to the biogenesis of secretory storage granules.
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28
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Arf1 and membrane curvature cooperate to recruit Arfaptin2 to liposomes. PLoS One 2013; 8:e62963. [PMID: 23638170 PMCID: PMC3639266 DOI: 10.1371/journal.pone.0062963] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2012] [Accepted: 03/27/2013] [Indexed: 11/19/2022] Open
Abstract
Arfaptin2 contains a Bin/Amphiphysin/Rvs (BAR) domain and directly interacts with proteins of the Arf/Arl family in their active GTP-bound state. It has been proposed that BAR domains are able to sense membrane curvature and to induce membrane tubulation. We report here that active Arf1 is required for the recruitment of Arfaptin2 to artificial liposomes mimicking the Golgi apparatus lipid composition. The Arf1-dependent recruitment of Arfaptin2 increases with membrane curvature, while the recruitment of Arf1 itself is not sensitive to curvature. At high protein concentrations, the binding of Arfaptin2 induces membrane tubulation. Finally, membrane-bound Arfaptin2 is released from the liposome when ArfGAP1 catalyzes the hydrolysis of GTP to GDP in Arf1. These results show that both Arf1 activation and high membrane curvature are required for efficient recruitment of Arfaptin2 to membranes.
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29
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Adult neuronal Arf6 controls ethanol-induced behavior with Arfaptin downstream of Rac1 and RhoGAP18B. J Neurosci 2013; 32:17706-13. [PMID: 23223291 DOI: 10.1523/jneurosci.1944-12.2012] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
Alcohol use disorders affect millions of individuals. However, the genes and signaling pathways involved in behavioral ethanol responses and addiction are poorly understood. Here we identify a conserved biochemical pathway that underlies the sedating effects of ethanol in Drosophila. Mutations in the Arf6 small GTPase signaling pathway cause hypersensitivity to ethanol-induced sedation. We show that Arf6 functions in the adult nervous system to control ethanol-induced behavior. We also find that the Drosophila Arfaptin protein directly binds to the activated forms of Arf6 and Rac1 GTPases, and mutants in Arfaptin also display ethanol sensitivity. Arf6 acts downstream of Rac1 and Arfaptin to regulate ethanol-induced behaviors, and we thus demonstrate that this conserved Rac1/Arfaptin/Arf6 pathway is a major mediator of ethanol-induced behavioral responses.
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Rab6a/a' are important Golgi regulators of pro-inflammatory TNF secretion in macrophages. PLoS One 2013; 8:e57034. [PMID: 23437303 PMCID: PMC3578815 DOI: 10.1371/journal.pone.0057034] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Accepted: 01/16/2013] [Indexed: 02/06/2023] Open
Abstract
Lipopolysaccharide (LPS)-activated macrophages secrete pro-inflammatory cytokines, including tumor necrosis factor (TNF) to elicit innate immune responses. Secretion of these cytokines is also a major contributing factor in chronic inflammatory disease. In previous studies we have begun to elucidate the pathways and molecules that mediate the intracellular trafficking and secretion of TNF. Rab6a and Rab6a' (collectively Rab6) are trans-Golgi-localized GTPases known for roles in maintaining Golgi structure and Golgi-associated trafficking. We found that induction of TNF secretion by LPS promoted the selective increase of Rab6 expression. Depletion of Rab6 (via siRNA and shRNA) resulted in reorganization of the Golgi ribbon into more compact structures that at the resolution of electron microcopy consisted of elongated Golgi stacks that likely arose from fusion of smaller Golgi elements. Concomitantly, the delivery of TNF to the cell surface and subsequent release into the media was reduced. Dominant negative mutants of Rab6 had similar effects in disrupting TNF secretion. In live cells, Rab6-GFP were localized on trans-Golgi network (TGN)-derived tubular carriers demarked by the golgin p230. Rab6 depletion and inactive mutants altered carrier egress and partially reduced p230 membrane association. Our results show that Rab6 acts on TNF trafficking at the level of TGN exit in tubular carriers and our findings suggest Rab6 may stabilize p230 on the tubules to facilitate TNF transport. Both Rab6 isoforms are needed in macrophages for Golgi stack organization and for the efficient post-Golgi transport of TNF. This work provides new insights into Rab6 function and into the role of the Golgi complex in cytokine secretion in inflammatory macrophages.
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Gehart H, Goginashvili A, Beck R, Morvan J, Erbs E, Formentini I, De Matteis M, Schwab Y, Wieland F, Ricci R. The BAR Domain Protein Arfaptin-1 Controls Secretory Granule Biogenesis at the trans-Golgi Network. Dev Cell 2012; 23:756-68. [DOI: 10.1016/j.devcel.2012.07.019] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2012] [Revised: 07/02/2012] [Accepted: 07/24/2012] [Indexed: 12/29/2022]
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Nakamura K, Man Z, Xie Y, Hanai A, Makyio H, Kawasaki M, Kato R, Shin HW, Nakayama K, Wakatsuki S. Structural basis for membrane binding specificity of the Bin/Amphiphysin/Rvs (BAR) domain of Arfaptin-2 determined by Arl1 GTPase. J Biol Chem 2012; 287:25478-89. [PMID: 22679020 DOI: 10.1074/jbc.m112.365783] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Membrane-sculpting BAR (Bin/Amphiphysin/Rvs) domains form a crescent-shaped homodimer that can sense and induce membrane curvature through its positively charged concave face. We have recently shown that Arfaptin-2, which was originally identified as a binding partner for the Arf and Rac1 GTPases, binds to Arl1 through its BAR domain and is recruited onto Golgi membranes. There, Arfaptin-2 induces membrane tubules. Here, we report the crystal structure of the Arfaptin-2 BAR homodimer in complex with two Arl1 molecules bound symmetrically to each side, leaving the concave face open for membrane association. The overall structure of the Arl1·Arfaptin-2 BAR complex closely resembles that of the PX-BAR domain of sorting nexin 9, suggesting similar mechanisms underlying BAR domain targeting to specific organellar membranes. The Arl1·Arfaptin-2 BAR structure suggests that one of the two Arl1 molecules competes with Rac1, which binds to the concave face of the Arfaptin-2 BAR homodimer and may hinder its membrane association.
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Affiliation(s)
- Kensuke Nakamura
- Structural Biology Research Center, Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization, KEK, Tsukuba, Ibaraki 305-0801, Japan
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Makyio H, Ohgi M, Takei T, Takahashi S, Takatsu H, Katoh Y, Hanai A, Ueda T, Kanaho Y, Xie Y, Shin HW, Kamikubo H, Kataoka M, Kawasaki M, Kato R, Wakatsuki S, Nakayama K. Structural basis for Arf6-MKLP1 complex formation on the Flemming body responsible for cytokinesis. EMBO J 2012; 31:2590-603. [PMID: 22522702 DOI: 10.1038/emboj.2012.89] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2011] [Accepted: 03/15/2012] [Indexed: 01/17/2023] Open
Abstract
A small GTPase, Arf6, is involved in cytokinesis by localizing to the Flemming body (the midbody). However, it remains unknown how Arf6 contributes to cytokinesis. Here, we demonstrate that Arf6 directly interacts with mitotic kinesin-like protein 1 (MKLP1), a Flemming body-localizing protein essential for cytokinesis. The crystal structure of the Arf6-MKLP1 complex reveals that MKLP1 forms a homodimer flanked by two Arf6 molecules, forming a 2:2 heterotetramer containing an extended β-sheet composed of 22 β-strands that spans the entire heterotetramer, suitable for interaction with a concave membrane surface at the cleavage furrow. We show that, during cytokinesis, Arf6 is first accumulated around the cleavage furrow and, prior to abscission, recruited onto the Flemming body via interaction with MKLP1. We also show by structure-based mutagenesis and siRNA-mediated knockdowns that the complex formation is required for completion of cytokinesis. A model based on these results suggests that the Arf6-MKLP1 complex plays a crucial role in cytokinesis by connecting the microtubule bundle and membranes at the cleavage plane.
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Affiliation(s)
- Hisayoshi Makyio
- Structural Biology Research Center, Photon Factory, Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), Ibaraki, Japan
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Abstract
Membrane-bound transport carriers are used to transfer cargo between membranes of the secretory and the endocytic pathways. The generation of these carriers can be classified into three steps: segregation of cargo away from the residents of a donor compartment (cargo sorting), generation of membrane curvature commensurate with the size of the cargo (membrane budding or tubulation), and finally separation of the nascent carrier from the donor membrane by a scission or membrane fission event. This review summarizes advances in our understanding of some of the best-characterized proteins required for the membrane fission that separates a transport carrier from its progenitor compartment: the large GTPase dynamin, the small guanine nucleotide-binding (G) proteins of the Arf family, BAR (Bin-amphiphysin-Rvs) domain proteins, and protein kinase D. These proteins share their ability to insert into membranes and oligomerize to create the large curvatures; however, the overall process of fission that involves these proteins appears to be quite different.
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Affiliation(s)
- Felix Campelo
- Department of Cell and Developmental Biology, Center for Genomic Regulation (CRG) and UPF, 08003 Barcelona, Spain
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Shin HW, Takatsu H, Nakayama K. Mechanisms of membrane curvature generation in membrane traffic. MEMBRANES 2012; 2:118-33. [PMID: 24957965 PMCID: PMC4021884 DOI: 10.3390/membranes2010118] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2012] [Revised: 02/20/2012] [Accepted: 02/21/2012] [Indexed: 11/17/2022]
Abstract
During the vesicular trafficking process, cellular membranes undergo dynamic morphological changes, in particular at the vesicle generation and fusion steps. Changes in membrane shape are regulated by small GTPases, coat proteins and other accessory proteins, such as BAR domain-containing proteins. In addition, membrane deformation entails changes in the lipid composition as well as asymmetric distribution of lipids over the two leaflets of the membrane bilayer. Given that P4-ATPases, which catalyze unidirectional flipping of lipid molecules from the exoplasmic to the cytoplasmic leaflets of the bilayer, are crucial for the trafficking of proteins in the secretory and endocytic pathways, changes in the lipid composition are involved in the vesicular trafficking process. Membrane remodeling is under complex regulation that involves the composition and distribution of lipids as well as assembly of proteins.
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Affiliation(s)
- Hye-Won Shin
- Career-Path Promotion Unit for Young Life Scientists, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.
| | - Hiroyuki Takatsu
- Career-Path Promotion Unit for Young Life Scientists, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.
| | - Kazuhisa Nakayama
- Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan.
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Christis C, Munro S. The small G protein Arl1 directs the trans-Golgi-specific targeting of the Arf1 exchange factors BIG1 and BIG2. ACTA ACUST UNITED AC 2012; 196:327-35. [PMID: 22291037 PMCID: PMC3275380 DOI: 10.1083/jcb.201107115] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Specificity in Arf1 GEF recruitment to the trans-Golgi, and thus in localized Arf1 activation, is provided by an Arf-like G protein. The small G protein Arf1 regulates Golgi traffic and is activated by two related types of guanine nucleotide exchange factor (GEF). GBF1 acts at the cis-Golgi, whereas BIG1 and its close paralog BIG2 act at the trans-Golgi. Peripheral membrane proteins such as these GEFs are often recruited to membranes by small G proteins, but the basis for specific recruitment of Arf GEFs, and hence Arfs, to Golgi membranes is not understood. In this paper, we report a liposome-based affinity purification method to identify effectors for small G proteins of the Arf family. We validate this with the Drosophila melanogaster Arf1 orthologue (Arf79F) and the related class II Arf (Arf102F), which showed a similar pattern of effector binding. Applying the method to the Arf-like G protein Arl1, we found that it binds directly to Sec71, the Drosophila ortholog of BIG1 and BIG2, via an N-terminal region. We show that in mammalian cells, Arl1 is necessary for Golgi recruitment of BIG1 and BIG2 but not GBF1. Thus, Arl1 acts to direct a trans-Golgi–specific Arf1 GEF, and hence active Arf1, to the trans side of the Golgi.
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Affiliation(s)
- Chantal Christis
- Medical Research Council Laboratory of Molecular Biology, Cambridge CB2 0QH, England, UK
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Anitei M, Hoflack B. Bridging membrane and cytoskeleton dynamics in the secretory and endocytic pathways. Nat Cell Biol 2011; 14:11-9. [PMID: 22193159 DOI: 10.1038/ncb2409] [Citation(s) in RCA: 152] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Transport carriers regulate membrane flow between compartments of the secretory and endocytic pathways in eukaryotic cells. Carrier biogenesis is assisted by microtubules, actin filaments and their associated motors that link to membrane-associated coats, adaptors and accessory proteins. We summarize here how the biochemical properties of membranes inform their interactions with cytoskeletal regulators. We also discuss how the forces generated by the cytoskeleton and motor proteins alter the biophysical properties and the shape of membranes. The interplay between the cytoskeleton and membrane proteins ensures tight spatial and temporal control of carrier biogenesis, which is essential for cellular homeostasis.
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Affiliation(s)
- Mihaela Anitei
- Biotechnology Centre, Technische Universität Dresden, Tatzberg 47/49, 01307 Dresden, Germany
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Rao Y, Haucke V. Membrane shaping by the Bin/amphiphysin/Rvs (BAR) domain protein superfamily. Cell Mol Life Sci 2011; 68:3983-93. [PMID: 21769645 PMCID: PMC11114942 DOI: 10.1007/s00018-011-0768-5] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Revised: 06/27/2011] [Accepted: 06/30/2011] [Indexed: 01/27/2023]
Abstract
BAR domain superfamily proteins have emerged as central regulators of dynamic membrane remodeling, thereby playing important roles in a wide variety of cellular processes, such as organelle biogenesis, cell division, cell migration, secretion, and endocytosis. Here, we review the mechanistic and structural basis for the membrane curvature-sensing and deforming properties of BAR domain superfamily proteins. Moreover, we summarize the present state of knowledge with respect to their regulation by autoinhibitory mechanisms or posttranslational modifications, and their interactions with other proteins, in particular with GTPases, and with membrane lipids. We postulate that BAR superfamily proteins act as membrane-deforming scaffolds that spatiotemporally orchestrate membrane remodeling.
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Affiliation(s)
- Yijian Rao
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Takustraße 6, 14195 Berlin, Germany
- Present Address: Max Planck Institute for Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany
| | - Volker Haucke
- Institute of Chemistry and Biochemistry, Freie Universität Berlin, Takustraße 6, 14195 Berlin, Germany
- NeuroCure Cluster of Excellence, Charité Berlin, Charitéplatz 1, 10117 Berlin, Germany
- Leibniz-Institut für Molekulare Pharmakologie (FMP), Robert-Rössle-Straße 10, 13125 Berlin, Germany
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ARF family G proteins and their regulators: roles in membrane transport, development and disease. Nat Rev Mol Cell Biol 2011; 12:362-75. [PMID: 21587297 PMCID: PMC3245550 DOI: 10.1038/nrm3117] [Citation(s) in RCA: 674] [Impact Index Per Article: 51.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The ADP-ribosylation factor (ARF) family of guanine-nucleotide-binding (G) proteins, including the ARF proteins, ARF-like (ARL) proteins and SAR1, regulates membrane traffic and organelle structure, and each family member is regulated through a cycle of GTP binding and GTP hydrolysis, which activate and inactivate, respectively, the G protein. Traditionally, ARFs have been characterized for their immediate effects in the recruitment of coat proteins to drive cargo sorting, the recruitment of enzymes that can alter membrane lipid composition and the regulation of cytoskeletal factors. Now, new roles for ARFs have been discovered at the Golgi complex, for example in driving lipid transport. ARL proteins are also being increasingly linked to coordination of trafficking with cytoskeletal processes, for example during ciliogenesis. There is particular interest in the mechanisms that control recruitment of the ARF guanine nucleotide exchange factors (GEFs) that mediate GTP binding to ARFs and, in the case of the cytohesin (also known as ARNO) GEF, membrane recruitment is coupled to relief of autoinhibition. GEFs such as cytohesin may also participate in a cascade of activation between particular pairs of ARFs. Traditionally, G protein signalling has been viewed as a linear pathway, with the GDP-bound form of an ARF protein being inactive; however, more recent studies have highlighted novel roles for these GDP-bound forms and have also shown that GEFs and GTPase-activating proteins (GAPs) themselves can engage in distinct signalling responses through scaffolding functions.
The ADP-ribosylation factor (ARF) and ARF-like (ARL) family of G proteins, which are known to regulate membrane traffic and organelle structure, are emerging as regulators of diverse processes, including lipid and cytoskeletal transport. Although traditionally viewed as part of a linear signalling pathway, ARFs and their regulators must now be considered to exist within functional networks, in which both the 'inactive' ARF and the regulators themselves can mediate distinct effects. Members of the ADP-ribosylation factor (ARF) family of guanine-nucleotide-binding (G) proteins, including the ARF-like (ARL) proteins and SAR1, regulate membrane traffic and organelle structure by recruiting cargo-sorting coat proteins, modulating membrane lipid composition, and interacting with regulators of other G proteins. New roles of ARF and ARL proteins are emerging, including novel functions at the Golgi complex and in cilia formation. Their function is under tight spatial control, which is mediated by guanine nucleotide exchange factors (GEFs) and GTPase-activating proteins (GAPs) that catalyse GTP exchange and hydrolysis, respectively. Important advances are being gained in our understanding of the functional networks that are formed not only by the GEFs and GAPs themselves but also by the inactive forms of the ARF proteins.
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Takashima K, Saitoh A, Hirose S, Nakai W, Kondo Y, Takasu Y, Kakeya H, Shin HW, Nakayama K. GBF1-Arf-COPI-ArfGAP-mediated Golgi-to-ER Transport Involved in Regulation of Lipid Homeostasis. Cell Struct Funct 2011; 36:223-35. [DOI: 10.1247/csf.11035] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Affiliation(s)
- Kouhei Takashima
- Department of Physiological Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Akina Saitoh
- Department of Physiological Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Shohei Hirose
- Department of Physiological Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Waka Nakai
- Department of Physiological Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Yumika Kondo
- Department of Physiological Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Yasuaki Takasu
- Department of System Chemotherapy and Molecular Sciences, Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Hideaki Kakeya
- Department of System Chemotherapy and Molecular Sciences, Graduate School of Pharmaceutical Sciences, Kyoto University
| | - Hye-Won Shin
- Department of Physiological Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University
- Career-Path Promotion Unit for Young Life Scientists, Kyoto University
| | - Kazuhisa Nakayama
- Department of Physiological Chemistry, Graduate School of Pharmaceutical Sciences, Kyoto University
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