1
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Sun J, Chang J, Guo Z, Sun H, Xu J, Liu X, Sun W. Proteomics Analysis of Renal Cell Line Caki-2 with AFMID Overexpression and Potential Biomarker Discovery in Urine. J Proteome Res 2024. [PMID: 39213636 DOI: 10.1021/acs.jproteome.4c00431] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/04/2024]
Abstract
Aromatic caninurine formamase (AFMID) is an enzyme involved in the tryptophan pathway, metabolizing N-formylkynurenine to kynurenine. AFMID had been found significantly downregulated in clear cell renal cell carcinoma (ccRCC) in both tissue and urine samples. Although ccRCC is characterized by a typical Warburg-like phenotype, mitochondrial dysfunction, and elevated fat deposition, it is unknown whether AFMID plays a role in tumorigenesis and the development of ccRCC. In the present study, AFMID overexpression had inhibitory effects for ccRCC cells, decreasing the rate of cell proliferation. Quantitative proteomics showed that AFMID overexpression altered cellular signaling pathways involved in cell growth and cellular metabolism pathways, including lipid metabolism and inositol phosphate metabolism. Further urine proteomic analysis indicated that cellular function dysfunction with AFMID overexpression could be reflected in the urine. The activity of predicted upregulators DDX58, TREX1, TGFB1, SMARCA4, and TNF in ccRCC cells and urine showed opposing change trends. Potential urinary biomarkers were tentatively discovered and further validated using an independent cohort. The protein panel of APOC3, UMOD, and CILP achieved an AUC value of 0.862 for the training cohort and 0.883 for the validation cohort. The present study is of significance in terms of highlighting various aspects of pathway changes associated with AFMID enzymes, discovering potential specific biomarkers for potential patient diagnosis, and therapeutic targeting.
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Affiliation(s)
- Jiameng Sun
- Core Instrument Facility, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, 5 Dong Dan San Tiao, Beijing 100005, China
| | - Jinchun Chang
- National Institute of Biological Sciences,7 Science Park Road ZGC Life Science Park, Beijing 102206, China
- School of Health, Quanzhou Medical College, No. 2 Anji Road, Luojiang District, Quanzhou City, Fujian Province 362011, China
| | - Zhengguang Guo
- Core Instrument Facility, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, 5 Dong Dan San Tiao, Beijing 100005, China
| | - Haidan Sun
- Core Instrument Facility, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, 5 Dong Dan San Tiao, Beijing 100005, China
| | - Jiyu Xu
- Core Instrument Facility, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, 5 Dong Dan San Tiao, Beijing 100005, China
| | - Xiaoyan Liu
- Core Instrument Facility, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, 5 Dong Dan San Tiao, Beijing 100005, China
| | - Wei Sun
- Core Instrument Facility, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, 5 Dong Dan San Tiao, Beijing 100005, China
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2
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Park K, Ju S, Choi H, Gao P, Bang G, Choi JH, Jang J, Morris AJ, Kang BH, Hsu VW, Park SY. PITPβ promotes COPI vesicle fission through lipid transfer and membrane contact formation. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.27.596058. [PMID: 38853868 PMCID: PMC11160616 DOI: 10.1101/2024.05.27.596058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Intracellular transport among organellar compartments occurs in two general ways, by membrane-bound carriers or membrane contacts. Specific circumstances that involve the coordination of these two modes of transport remain to be defined. Studying Coat Protein I (COPI) transport, we find that phosphatidylcholine with short acyl chains (sPC) is delivered through membrane contact from the endoplasmic reticulum (ER) to sites of COPI vesicle formation at the Golgi to support the fission stage. Phosphatidylinositol transfer protein beta (PITPβ) plays a key role in this process, with the elucidation of this role advancing a new understanding of how PITPβ acts, providing a mechanistic understanding of a specific circumstance when vesicular transport requires membrane contact, and contributing to a basic understanding of how transport carriers in a model intracellular pathway are formed.
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Affiliation(s)
- Kunyou Park
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea
- Division of Rheumatology, Inflammation and Immunity, Brigham and Women’s Hospital, and Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Sungeun Ju
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Hyewon Choi
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Peng Gao
- School of Life Sciences, State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Geul Bang
- Research Center for Bioconvergence Analysis, Korea Basic Science Institute, Cheongju, Republic of Korea
| | - Jung Hoon Choi
- Department of Bio-Chemical Analysis, Korea Basic Science Institute, Cheongju, Republic of Korea
| | - Jiwon Jang
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea
| | - Andrew J. Morris
- University of Arkansas for Medical Sciences and Central Arkansas Veterans Affairs Healthcare System, Little Rock, AR 72205, USA
| | - Byung-Ho Kang
- School of Life Sciences, State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China
| | - Victor W. Hsu
- Division of Rheumatology, Inflammation and Immunity, Brigham and Women’s Hospital, and Department of Medicine, Harvard Medical School, Boston, MA 02115, USA
| | - Seung-Yeol Park
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Gyeongbuk 37673, Republic of Korea
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3
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G. Dornan L, C. Simpson J. Rab6-mediated retrograde trafficking from the Golgi: the trouble with tubules. Small GTPases 2023; 14:26-44. [PMID: 37488775 PMCID: PMC10392741 DOI: 10.1080/21541248.2023.2238330] [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: 06/15/2023] [Revised: 07/13/2023] [Accepted: 07/15/2023] [Indexed: 07/26/2023] Open
Abstract
Next year marks one-quarter of a century since the discovery of the so-called COPI-independent pathway, which operates between the Golgi apparatus and the endoplasmic reticulum (ER) in eukaryotic cells. Unlike almost all other intracellular trafficking pathways, this pathway is not regulated by the physical accumulation of multisubunit proteinaceous coat molecules, but instead by the small GTPase Rab6. What also sets it apart from other pathways is that the transport carriers themselves often take the form of tubules, rather than conventional vesicles. In this review, we assess the relevant literature that has accumulated to date, in an attempt to provide a concerted description of how this pathway is regulated. We discuss the possible cargo molecules that are carried in this pathway, and the likely mechanism of Rab6 tubule biogenesis, including how the cargo itself may play a critical role. We also provide perspective surrounding the various molecular motors of the kinesin, myosin and dynein families that have been implicated in driving Rab6-coated tubular membranes long distances through the cell prior to delivering their cargo to the ER. Finally, we also raise several important questions that require resolution, if we are to ultimately provide a comprehensive molecular description of how the COPI-independent pathway is controlled.
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Affiliation(s)
- Lucy G. Dornan
- Cell Screening Laboratory, UCD School of Biology & Environmental Science, University College Dublin, Dublin, Ireland
| | - Jeremy C. Simpson
- Cell Screening Laboratory, UCD School of Biology & Environmental Science, University College Dublin, Dublin, Ireland
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4
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Okundaye B, Biyani N, Moitra S, Zhang K. The Golgi-localized sphingosine-1-phosphate phosphatase is indispensable for Leishmania major. Sci Rep 2022; 12:16064. [PMID: 36163400 PMCID: PMC9513092 DOI: 10.1038/s41598-022-20249-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2022] [Accepted: 09/12/2022] [Indexed: 11/09/2022] Open
Abstract
Sphingosine-1-phosphate phosphatase (SPP) catalyzes the dephosphorylation of sphingosine-1-phosphate (S1P) into sphingosine, the reverse reaction of sphingosine kinase. In mammals, S1P acts as a potent bioactive molecule regulating cell proliferation, migration, and immunity. In Leishmania, S1P production is crucial for the synthesis of ethanolamine and choline phospholipids, and cell survival under stress conditions. To better understand the roles of S1P, we characterized a SPP ortholog in Leishmania major which displays activity towards S1P but not structurally related lipids such as ceramide-1-phosphate or lysophosphatidic acid. While this enzyme is found in the endoplasmic reticulum in mammalian cells, L. major SPP is localized at the Golgi apparatus. Importantly, chromosomal SPP alleles cannot be deleted from L. major even with the addition of a complementing episome, suggesting that endogenously expressed SPP is essential. Finally, SPP overexpression in L. major leads to a slower growth rate and heightened sensitivity to brefeldin A and sodium orthovanadate. Together, these results suggest that the equilibrium between S1P and sphingosine is vital for the function of Golgi apparatus in Leishmania.
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Affiliation(s)
- Brian Okundaye
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, 79409, USA
- The Institute of Environmental and Human Health, Texas Tech University, Lubbock, TX, 79409, USA
| | - Neha Biyani
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, 79409, USA
- Lantern Pharma Inc., 1920 McKinney Ave., Dallas, TX, 75201, USA
| | - Samrat Moitra
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, 79409, USA
| | - Kai Zhang
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, 79409, USA.
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5
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Lehmann M. Diverse roles of phosphatidate phosphatases in insect development and metabolism. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 2021; 133:103469. [PMID: 32931938 PMCID: PMC7952469 DOI: 10.1016/j.ibmb.2020.103469] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 08/10/2020] [Accepted: 08/24/2020] [Indexed: 06/11/2023]
Abstract
The conversion of the glycerophospholipid phosphatidic acid (PA) into diacylglycerol (DAG) is essential for the biosynthesis of membrane phospholipids and storage fats. Importantly, both PA and DAG can also serve signaling functions in the cell. The dephosphorylation of PA that yields DAG can be executed by two different classes of enzymes, Mg2+-dependent lipins and Mg2+-independent lipid phosphate phosphatases. Here, I will discuss the current status of research directed at understanding the roles of these enzymes in insect development and metabolism. Special emphasis will be given to studies in the model organism Drosophila melanogaster.
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Affiliation(s)
- Michael Lehmann
- Department of Biological Sciences, SCEN 601, 1 University of Arkansas, Fayetteville, AR, 72701, USA.
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6
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Sphingomyelin synthase-related protein generates diacylglycerol via the hydrolysis of glycerophospholipids in the absence of ceramide. J Biol Chem 2021; 296:100454. [PMID: 33621517 PMCID: PMC7988496 DOI: 10.1016/j.jbc.2021.100454] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 02/16/2021] [Accepted: 02/19/2021] [Indexed: 01/20/2023] Open
Abstract
Diacylglycerol (DG) is a well-established lipid second messenger. Sphingomyelin synthase (SMS)-related protein (SMSr) produces DG and ceramide phosphoethanolamine (CPE) by the transfer of phosphoethanolamine from phosphatidylethanolamine (PE) to ceramide. We previously reported that human SMSr overexpressed in COS-7 cells significantly increased DG levels, particularly saturated and/or monounsaturated fatty acid-containing DG molecular species, and provided DG to DG kinase (DGK) δ, which regulates various pathophysiological events, including epidermal growth factor-dependent cell proliferation, type 2 diabetes, and obsessive-compulsive disorder. However, mammalian SMSr puzzlingly produces only trace amounts of CPE/DG. To clarify this discrepancy, we highly purified SMSr and examined its activities other than CPE synthase. Intriguingly, purified SMSr showed a DG-generating activity via hydrolysis of PE, phosphatidic acid (PA), phosphatidylinositol (PI), and phosphatidylcholine (PC) in the absence of ceramide. DG generation through the PA phosphatase (PAP) activity of SMSr was approximately 300-fold higher than that with PE and ceramide. SMSr hydrolyzed PI ten times stronger than PI(4,5)bisphosphate (PI(4,5)P2). The PAP and PC-phospholipase C (PLC) activities of SMSr were inhibited by propranolol, a PAP inhibitor, and by D609, an SMS/PC-PLC inhibitor. Moreover, SMSr showed substrate selectivity for saturated and/or monounsaturated fatty acid-containing PA molecular species, but not arachidonic-acid-containing PA, which is exclusively generated in the PI(4,5)P2 cycle. We confirmed that SMSr expressed in COS-7 cells showed PAP and PI-PLC activities. Taken together, our study indicated that SMSr possesses previously unrecognized enzyme activities, PAP and PI/PE/PC-PLC, and constitutes a novel DG/PA signaling pathway together with DGKδ, which is independent of the PI(4,5)P2 cycle.
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7
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Galano M, Li Y, Li L, Sottas C, Papadopoulos V. Role of Constitutive STAR in Leydig Cells. Int J Mol Sci 2021; 22:2021. [PMID: 33670702 PMCID: PMC7922663 DOI: 10.3390/ijms22042021] [Citation(s) in RCA: 38] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 02/13/2021] [Accepted: 02/17/2021] [Indexed: 12/15/2022] Open
Abstract
Leydig cells contain significant amounts of constitutively produced steroidogenic acute regulatory protein (STAR; STARD1). Hormone-induced STAR plays an essential role in inducing the transfer of cholesterol into the mitochondria for hormone-dependent steroidogenesis. STAR acts at the outer mitochondrial membrane, where it interacts with a protein complex, which includes the translocator protein (TSPO). Mutations in STAR cause lipoid congenital adrenal hyperplasia (lipoid CAH), a disorder characterized by severe defects in adrenal and gonadal steroid production; in Leydig cells, the defects are seen mainly after the onset of hormone-dependent androgen formation. The function of constitutive STAR in Leydig cells is unknown. We generated STAR knockout (KO) MA-10 mouse tumor Leydig cells and showed that STAR KO cells failed to form progesterone in response to dibutyryl-cAMP and to TSPO drug ligands, but not to 22(R)-hydroxycholesterol, which is a membrane-permeable intermediate of the CYP11A1 reaction. Electron microscopy of STAR KO cells revealed that the number and size of lipid droplets were similar to those in wild-type (WT) MA-10 cells. However, the density of lipid droplets in STAR KO cells was drastically different than that seen in WT cells. We isolated the lipid droplets and analyzed their content by liquid chromatography-mass spectrometry. There was a significant increase in cholesteryl ester and phosphatidylcholine content in STAR KO cell lipid droplets, but the most abundant increase was in the amount of diacylglycerol (DAG); DAG 38:1 was the predominantly affected species. Lastly, we identified genes involved in DAG signaling and lipid metabolism which were differentially expressed between WT MA-10 and STAR KO cells. These results suggest that constitutive STAR in Leydig cells is involved in DAG accumulation in lipid droplets, in addition to cholesterol transport. The former event may affect cell functions mediated by DAG signaling.
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Affiliation(s)
| | | | | | | | - Vassilios Papadopoulos
- Department of Pharmacology and Pharmaceutical Sciences, School of Pharmacy, University of Southern California, Los Angeles, CA 90089, USA; (M.G.); (Y.L.); (L.L.); (C.S.)
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8
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Singla RK, Sultana A, Alam MS, Shen B. Regulation of Pain Genes-Capsaicin vs Resiniferatoxin: Reassessment of Transcriptomic Data. Front Pharmacol 2020; 11:551786. [PMID: 33192502 PMCID: PMC7658921 DOI: 10.3389/fphar.2020.551786] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Accepted: 09/11/2020] [Indexed: 02/05/2023] Open
Abstract
Emerging evidence has shown a strong association between neuropathic pain and chronic diseases. In recent years, the treatment of neuropathic pain has attracted more attention. Natural products, such as capsaicin and resiniferatoxin, have been well utilized to treat this disease. In this study, we aim to compare the regulatory effects of capsaicin and resiniferatoxin on pain-related genes as well as on genes with no direct association with pain. Public transcriptomic and microarray data on gene expression in the dorsal root ganglia and genes associated with TRPV1 (+) neurons were obtained from the GEO database and then analyzed. Differentially expressed genes were selected for further functional analysis, including pathway enrichment, protein-protein interaction, and regulatory network analysis. Pain-associated genes were extracted with the reference of two pain gene databases and the effects of these two natural drugs on the pain-associated genes were measured. The results of our research indicate that as compared to capsaicin, resiniferatoxin (RTX) regulates more non pain-associated genes and has a negative impact on beneficial genes (off-targets) which are supposed to alleviate nociception and hypersensitivity by themselves. So, based on this study, we may conclude that capsaicin may be less potent when compared to RTX, but it will elicit considerably less adverse effects too. Thereby confirming that capsaicin could be used for the efficient alleviation of neuropathic pain with possibly fewer side effects.
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Affiliation(s)
- Rajeev K Singla
- Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu, China
| | - Adiba Sultana
- Center for Systems Biology, Soochow University, Suzhou, China
| | - Md Shahin Alam
- Center for Systems Biology, Soochow University, Suzhou, China
| | - Bairong Shen
- Institutes for Systems Genetics, Frontiers Science Center for Disease-related Molecular Network, West China Hospital, Sichuan University, Chengdu, China
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9
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Interface of Phospholipase Activity, Immune Cell Function, and Atherosclerosis. Biomolecules 2020; 10:biom10101449. [PMID: 33076403 PMCID: PMC7602611 DOI: 10.3390/biom10101449] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Revised: 09/30/2020] [Accepted: 10/13/2020] [Indexed: 12/16/2022] Open
Abstract
Phospholipases are a family of lipid-altering enzymes that can either reduce or increase bioactive lipid levels. Bioactive lipids elicit signaling responses, activate transcription factors, promote G-coupled-protein activity, and modulate membrane fluidity, which mediates cellular function. Phospholipases and the bioactive lipids they produce are important regulators of immune cell activity, dictating both pro-inflammatory and pro-resolving activity. During atherosclerosis, pro-inflammatory and pro-resolving activities govern atherosclerosis progression and regression, respectively. This review will look at the interface of phospholipase activity, immune cell function, and atherosclerosis.
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10
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Tang X, Brindley DN. Lipid Phosphate Phosphatases and Cancer. Biomolecules 2020; 10:biom10091263. [PMID: 32887262 PMCID: PMC7564803 DOI: 10.3390/biom10091263] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 08/28/2020] [Accepted: 08/30/2020] [Indexed: 12/22/2022] Open
Abstract
Lipid phosphate phosphatases (LPPs) are a group of three enzymes (LPP1–3) that belong to a phospholipid phosphatase (PLPP) family. The LPPs dephosphorylate a wide spectrum of bioactive lipid phosphates, among which lysophosphatidate (LPA) and sphingosine 1-phosphate (S1P) are two important extracellular signaling molecules. The LPPs are integral membrane proteins, which are localized on plasma membranes and intracellular membranes, including the endoplasmic reticulum and Golgi network. LPPs regulate signaling transduction in cancer cells and demonstrate different effects in cancer progression through the breakdown of extracellular LPA and S1P and other intracellular substrates. This review is intended to summarize an up-to-date understanding about the functions of LPPs in cancers.
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Affiliation(s)
- Xiaoyun Tang
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2S2, Canada;
- Cancer Research Institute of Northern Alberta, University of Alberta, Edmonton, AB T6G 2E1, Canada
| | - David N. Brindley
- Department of Biochemistry, University of Alberta, Edmonton, AB T6G 2S2, Canada;
- Cancer Research Institute of Northern Alberta, University of Alberta, Edmonton, AB T6G 2E1, Canada
- Correspondence:
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11
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The late stage of COPI vesicle fission requires shorter forms of phosphatidic acid and diacylglycerol. Nat Commun 2019; 10:3409. [PMID: 31363100 PMCID: PMC6667475 DOI: 10.1038/s41467-019-11324-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 06/21/2019] [Indexed: 12/19/2022] Open
Abstract
Studies on vesicle formation by the Coat Protein I (COPI) complex have contributed to a basic understanding of how vesicular transport is initiated. Phosphatidic acid (PA) and diacylglycerol (DAG) have been found previously to be required for the fission stage of COPI vesicle formation. Here, we find that PA with varying lipid geometry can all promote early fission, but only PA with shortened acyl chains promotes late fission. Moreover, diacylglycerol (DAG) acts after PA in late fission, with this role of DAG also requiring shorter acyl chains. Further highlighting the importance of the short-chain lipid geometry for late fission, we find that shorter forms of PA and DAG promote the vesiculation ability of COPI fission factors. These findings advance a general understanding of how lipid geometry contributes to membrane deformation for vesicle fission, and also how proteins and lipids coordinate their actions in driving this process.
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12
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von Blume J, Hausser A. Lipid-dependent coupling of secretory cargo sorting and trafficking at the trans-Golgi network. FEBS Lett 2019; 593:2412-2427. [PMID: 31344259 PMCID: PMC8048779 DOI: 10.1002/1873-3468.13552] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 07/10/2019] [Accepted: 07/22/2019] [Indexed: 12/17/2022]
Abstract
In eukaryotic cells, the trans-Golgi network (TGN) serves as a platform for secretory cargo sorting and trafficking. In recent years, it has become evident that a complex network of lipid–lipid and lipid–protein interactions contributes to these key functions. This review addresses the role of lipids at the TGN with a particular emphasis on sphingolipids and diacylglycerol. We further highlight how these lipids couple secretory cargo sorting and trafficking for spatiotemporal coordination of protein transport to the plasma membrane.
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Affiliation(s)
- Julia von Blume
- Department of Cell Biology, Yale School of Medicine, New Haven, CT, USA.,Max Planck Institute of Biochemistry, Martinsried, Germany
| | - Angelika Hausser
- Institute of Cell Biology and Immunology, University of Stuttgart, Germany.,Stuttgart Research Center Systems Biology, University of Stuttgart, Germany
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13
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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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14
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Busnelli M, Manzini S, Parolini C, Escalante-Alcalde D, Chiesa G. Lipid phosphate phosphatase 3 in vascular pathophysiology. Atherosclerosis 2018. [DOI: 10.1016/j.atherosclerosis.2018.02.025] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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15
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Kavaliauskiene S, Torgersen ML, Lingelem ABD, Klokk TI, Lintonen T, Simolin H, Ekroos K, Skotland T, Sandvig K. Cellular effects of fluorodeoxyglucose: Global changes in the lipidome and alteration in intracellular transport. Oncotarget 2018; 7:79885-79900. [PMID: 27829218 PMCID: PMC5346758 DOI: 10.18632/oncotarget.13089] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 10/21/2016] [Indexed: 11/29/2022] Open
Abstract
2-fluoro-2-deoxy-D-glucose (FDG), labeled with 18F radioisotope, is the most common imaging agent used for positron emission tomography (PET) in oncology. However, little is known about the cellular effects of FDG. Another glucose analogue, 2-deoxy-D-glucose (2DG), has been shown to affect many cellular functions, including intracellular transport and lipid metabolism, and has been found to improve the efficacy of cancer chemotherapeutic agents in vivo. Thus, in the present study, we have investigated cellular effects of FDG with the focus on changes in cellular lipids and intracellular transport. By quantifying more than 200 lipids from 17 different lipid classes in HEp-2 cells and by analyzing glycosphingolipids from MCF-7, HT-29 and HBMEC cells, we have discovered that FDG treatment inhibits glucosylceramide synthesis and thus reduces cellular levels of glycosphingolipids. In addition, in HEp-2 cells the levels and/or species composition of other lipid classes, namely diacylglycerols, phosphatidic acids and phosphatidylinositols, were found to change upon treatment with FDG. Furthermore, we show here that FDG inhibits retrograde Shiga toxin transport and is much more efficient in protecting cells against the toxin than 2DG. In summary, our data reveal novel effects of FDG on cellular transport and glycosphingolipid metabolism, which suggest a potential clinical application of FDG as an adjuvant for cancer chemotherapy.
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Affiliation(s)
- Simona Kavaliauskiene
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Center for Cancer Biomedicine, Oslo University Hospital, Oslo, Norway.,Department of Biosciences, University of Oslo, Oslo, Norway
| | - Maria Lyngaas Torgersen
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Center for Cancer Biomedicine, Oslo University Hospital, Oslo, Norway
| | - Anne Berit Dyve Lingelem
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Center for Cancer Biomedicine, Oslo University Hospital, Oslo, Norway
| | - Tove Irene Klokk
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Center for Cancer Biomedicine, Oslo University Hospital, Oslo, Norway
| | | | | | | | - Tore Skotland
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Center for Cancer Biomedicine, Oslo University Hospital, Oslo, Norway
| | - Kirsten Sandvig
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway.,Center for Cancer Biomedicine, Oslo University Hospital, Oslo, Norway.,Department of Biosciences, University of Oslo, Oslo, Norway
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Chandra M, Escalante-Alcalde D, Bhuiyan MS, Orr AW, Kevil C, Morris AJ, Nam H, Dominic P, McCarthy KJ, Miriyala S, Panchatcharam M. Cardiac-specific inactivation of LPP3 in mice leads to myocardial dysfunction and heart failure. Redox Biol 2017; 14:261-271. [PMID: 28982073 PMCID: PMC5635346 DOI: 10.1016/j.redox.2017.09.015] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 09/15/2017] [Accepted: 09/19/2017] [Indexed: 11/28/2022] Open
Abstract
Lipid Phosphate phosphatase 3 (LPP3), encoded by the Plpp3 gene, is an enzyme that dephosphorylates the bioactive lipid mediator lysophosphatidic acid (LPA). To study the role of LPP3 in the myocardium, we generated a cardiac specific Plpp3 deficient mouse strain. Although these mice were viable at birth in contrast to global Plpp3 knockout mice, they showed increased mortality ~ 8 months. LPP3 deficient mice had enlarged hearts with reduced left ventricular performance as seen by echocardiography. Cardiac specific Plpp3 deficient mice had longer ventricular effective refractory periods compared to their Plpp3 littermates. We observed that lack of Lpp3 enhanced cardiomyocyte hypertrophy based on analysis of cell surface area. We found that lack of Lpp3 signaling was mediated through the activation of Rho and phospho-ERK pathways. There are increased levels of fetal genes Natriuretic Peptide A and B (Nppa and Nppb) expression indicating myocardial dysfunction. These mice also demonstrate mitochondrial dysfunction as evidenced by a significant decrease (P < 0.001) in the basal oxygen consumption rate, mitochondrial ATP production, and spare respiratory capacity as measured through mitochondrial bioenergetics. Histology and transmission electron microscopy of these hearts showed disrupted sarcomere organization and intercalated disc, with a prominent disruption of the cristae and vacuole formation in the mitochondria. Our findings suggest that LPA/LPP3-signaling nexus plays an important role in normal function of cardiomyocytes. PLPP3 plays a prominent role in the heart compared to other isoforms of PLPP. Lack of PLPP3 results in deteriorating cardiac function. PLPP3 regulates LPA signaling in cardiomyocytes. Presence of PLPP3 is required for optimal mitochondrial function. Increased free radical production is mitigated with activated PLPP3.
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Affiliation(s)
- Mini Chandra
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center, Shreveport, USA
| | - Diana Escalante-Alcalde
- División de Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, México DF, Mexico
| | - Md Shenuarin Bhuiyan
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center, Shreveport, USA
| | - Anthony Wayne Orr
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center, Shreveport, USA
| | - Christopher Kevil
- Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center, Shreveport, USA
| | - Andrew J Morris
- Division of Cardiovascular Medicine, University of Kentucky, Lexington, USA
| | - Hyung Nam
- Department of Pharmacology and Toxicology, Louisiana State University Health Sciences Center, Shreveport, USA
| | - Paari Dominic
- Division of Cardiology, Department of Medicine, Louisiana State University Health Sciences Center, Shreveport, USA
| | - Kevin J McCarthy
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center, Shreveport, USA; Department of Pathology and Translational Pathobiology, Louisiana State University Health Sciences Center, Shreveport, USA
| | - Sumitra Miriyala
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center, Shreveport, USA.
| | - Manikandan Panchatcharam
- Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center, Shreveport, USA.
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Serra-Peinado C, Sicart A, Llopis J, Egea G. Actin Filaments Are Involved in the Coupling of V0-V1 Domains of Vacuolar H+-ATPase at the Golgi Complex. J Biol Chem 2016; 291:7286-99. [PMID: 26872971 DOI: 10.1074/jbc.m115.675272] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2015] [Indexed: 11/06/2022] Open
Abstract
We previously reported that actin-depolymerizing agents promote the alkalization of the Golgi stack and thetrans-Golgi network. The main determinant of acidic pH at the Golgi is the vacuolar-type H(+)-translocating ATPase (V-ATPase), whose V1domain subunitsBandCbind actin. We have generated a GFP-tagged subunitB2construct (GFP-B2) that is incorporated into the V1domain, which in turn is coupled to the V0sector. GFP-B2 subunit is enriched at distal Golgi compartments in HeLa cells. Subcellular fractionation, immunoprecipitation, and inversal FRAP experiments show that the actin depolymerization promotes the dissociation of V1-V0domains, which entails subunitB2translocation from Golgi membranes to the cytosol. Moreover, molecular interaction between subunitsB2andC1and actin were detected. In addition, Golgi membrane lipid order disruption byd-ceramide-C6 causes Golgi pH alkalization. We conclude that actin regulates the Golgi pH homeostasis maintaining the coupling of V1-V0domains of V-ATPase through the binding of microfilaments to subunitsBandCand preserving the integrity of detergent-resistant membrane organization. These results establish the Golgi-associated V-ATPase activity as the molecular link between actin and the Golgi pH.
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Affiliation(s)
- Carla Serra-Peinado
- From the Department de Biologia Cellular, Immunologia i Neurociències, Facultat de Medicina, Universitat de Barcelona, E-08036 Barcelona
| | - Adrià Sicart
- From the Department de Biologia Cellular, Immunologia i Neurociències, Facultat de Medicina, Universitat de Barcelona, E-08036 Barcelona
| | - Juan Llopis
- the Facultad de Medicina de Albacete and Centro Regional de Investigaciones Biomédicas, Universidad de Castilla-La Mancha, E-0200 Albacete, Spain
| | - Gustavo Egea
- From the Department de Biologia Cellular, Immunologia i Neurociències, Facultat de Medicina, Universitat de Barcelona, E-08036 Barcelona, the Institut d'Investigació Biomèdica August Pi i Sunyer, E-08036 Barcelona, the Institut de Nanociència i Nanotecnologia (INUB), E-08036 Barcelona, and
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18
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Xie S, Naslavsky N, Caplan S. Diacylglycerol kinases in membrane trafficking. CELLULAR LOGISTICS 2015; 5:e1078431. [PMID: 27057419 DOI: 10.1080/21592799.2015.1078431] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2015] [Revised: 07/22/2015] [Accepted: 07/24/2015] [Indexed: 10/23/2022]
Abstract
Diacylglycerol kinases (DGKs) belong to a family of cytosolic kinases that regulate the phosphorylation of diacylglycerol (DAG), converting it into phosphatidic acid (PA). There are 10 known mammalian DGK isoforms, each with a different tissue distribution and substrate specificity. These differences allow regulation of cellular responses by fine-tuning the delicate balance of cellular DAG and PA. DGK isoforms are best characterized as mediators of signal transduction and immune function. However, since recent studies reveal that DAG and PA are also involved in the regulation of endocytic trafficking, it is therefore anticipated that DGKs also plays an important role in membrane trafficking. In this review, we summarize the literature discussing the role of DGK isoforms at different stages of endocytic trafficking, including endocytosis, exocytosis, endocytic recycling, and transport from/to the Golgi apparatus. Overall, these studies contribute to our understanding of the involvement of PA and DAG in endocytic trafficking, an area of research that is drawing increasing attention in recent years.
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Affiliation(s)
- Shuwei Xie
- Department of Biochemistry and Molecular Biology and the Fred and Pamela Buffett Cancer Center; University of Nebraska Medical Center ; Omaha, NE USA
| | - Naava Naslavsky
- Department of Biochemistry and Molecular Biology and the Fred and Pamela Buffett Cancer Center; University of Nebraska Medical Center ; Omaha, NE USA
| | - Steve Caplan
- Department of Biochemistry and Molecular Biology and the Fred and Pamela Buffett Cancer Center; University of Nebraska Medical Center ; Omaha, NE USA
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19
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Adiko AC, Babdor J, Gutiérrez-Martínez E, Guermonprez P, Saveanu L. Intracellular Transport Routes for MHC I and Their Relevance for Antigen Cross-Presentation. Front Immunol 2015; 6:335. [PMID: 26191062 PMCID: PMC4489332 DOI: 10.3389/fimmu.2015.00335] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 06/15/2015] [Indexed: 01/22/2023] Open
Abstract
Cross-presentation, in which exogenous antigens are presented via MHC I complexes, is involved both in the generation of anti-infectious and anti-tumoral cytotoxic CD8+ T cells and in the maintenance of immune tolerance. While cross-presentation was described almost four decades ago and while it is now established that some dendritic cell (DC) subsets are better than others in processing and cross-presenting internalized antigens, the involved molecular mechanisms remain only partially understood. Some of the least explored molecular mechanisms in cross-presentation concern the origin of cross-presenting MHC I molecules and the cellular compartments where antigenic peptide loading occurs. This review focuses on MHC I molecules and their intracellular trafficking. We discuss the source of cross-presenting MHC I in DCs as well as the role of the endocytic pathway in their recycling from the cell surface. Next, we describe the importance of the TAP peptide transporter for delivering peptides to MHC I during cross-presentation. Finally, we highlight the impact of innate immunity mechanisms on specific antigen cross-presentation mechanisms in which TLR activation modulates MHC I trafficking and TAP localization.
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Affiliation(s)
- Aimé Cézaire Adiko
- INSERM U1149, Faculté Bichat Medical School, ELR8252 CNRS, Center for Research on Inflammation , Paris , France ; Université Paris Diderot, Sorbonne Paris Cité , Paris , France
| | - Joel Babdor
- INSERM UMR 1163, Laboratory of Cellular and Molecular Mechanisms of Hematological Disorders and Therapeutic Implications , Paris , France ; Université Paris Descartes, Sorbonne Paris Cité , Paris , France ; Imagine Institute , Paris , France
| | - Enric Gutiérrez-Martínez
- Laboratory of Phagocyte Immunobiology, Peter Gorer Department of Immunobiology, King's College London , London , UK
| | - Pierre Guermonprez
- Laboratory of Phagocyte Immunobiology, Peter Gorer Department of Immunobiology, King's College London , London , UK
| | - Loredana Saveanu
- INSERM U1149, Faculté Bichat Medical School, ELR8252 CNRS, Center for Research on Inflammation , Paris , France ; Université Paris Diderot, Sorbonne Paris Cité , Paris , France
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20
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Tang X, Benesch MGK, Brindley DN. Lipid phosphate phosphatases and their roles in mammalian physiology and pathology. J Lipid Res 2015; 56:2048-60. [PMID: 25814022 DOI: 10.1194/jlr.r058362] [Citation(s) in RCA: 113] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Indexed: 12/20/2022] Open
Abstract
Lipid phosphate phosphatases (LPPs) are a group of enzymes that belong to a phosphatase/phosphotransferase family. Mammalian LPPs consist of three isoforms: LPP1, LPP2, and LPP3. They share highly conserved catalytic domains and catalyze the dephosphorylation of a variety of lipid phosphates, including phosphatidate, lysophosphatidate (LPA), sphingosine 1-phosphate (S1P), ceramide 1-phosphate, and diacylglycerol pyrophosphate. LPPs are integral membrane proteins, which are localized on plasma membranes with the active site on the outer leaflet. This enables the LPPs to degrade extracellular LPA and S1P, thereby attenuating their effects on the activation of surface receptors. LPP3 also exhibits noncatalytic effects at the cell surface. LPP expression on internal membranes, such as endoplasmic reticulum and Golgi, facilitates the metabolism of internal lipid phosphates, presumably on the luminal surface of these organelles. This action probably explains the signaling effects of the LPPs, which occur downstream of receptor activation. The three isoforms of LPPs show distinct and nonredundant effects in several physiological and pathological processes including embryo development, vascular function, and tumor progression. This review is intended to present an up-to-date understanding of the physiological and pathological consequences of changing the activities of the different LPPs, especially in relation to cell signaling by LPA and S1P.
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Affiliation(s)
- Xiaoyun Tang
- Signal Transduction Research Group, Department of Biochemistry, University of Alberta, Edmonton, Alberta, T6G 2S2, Canada
| | - Matthew G K Benesch
- Signal Transduction Research Group, Department of Biochemistry, University of Alberta, Edmonton, Alberta, T6G 2S2, Canada
| | - David N Brindley
- Signal Transduction Research Group, Department of Biochemistry, University of Alberta, Edmonton, Alberta, T6G 2S2, Canada
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21
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Sicart A, Katan M, Egea G, Sarri E. PLCγ1 participates in protein transport and diacylglycerol production triggered by cargo arrival at the Golgi. Traffic 2015; 16:250-66. [PMID: 25491205 DOI: 10.1111/tra.12246] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 11/26/2014] [Accepted: 11/26/2014] [Indexed: 02/02/2023]
Abstract
Diacylglycerol (DAG) is required for membrane traffic and structural organization at the Golgi. DAG is a lipid metabolite of several enzymatic reactions present at this organelle, but the mechanisms by which they are regulated are still unknown. Here, we show that cargo arrival at the Golgi increases the recruitment of the DAG-sensing constructs C1-PKCθ-GFP and the PKD-wt-GFP. The recruitment of both constructs was reduced by PLCγ1 silencing. Post-Golgi trafficking of transmembrane and soluble proteins was impaired in PLCγ1-silenced cells. Under basal conditions, PLCγ1 contributed to the maintenance of the pool of DAG associated with the Golgi and to the structural organization of the organelle. Finally, we show that cytosolic phospholipase C (PLC) can hydrolyse phosphatidylinositol 4-phosphate in isolated Golgi membranes. Our results indicate that PLCγ1 is part of the molecular mechanism that couples cargo arrival at the Golgi with DAG production to co-ordinate the formation of transport carriers for post-Golgi traffic.
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Affiliation(s)
- Adrià Sicart
- Departament de Biologia Cel·lular, Immunologia i Neurociències, Facultat de Medicina, Universitat de Barcelona, C/ Casanova, 143, 08036, Barcelona, Spain; Current address: Vlaams Instituut voor Biotechnologie (VIB), Centre for the Biology of Disease and KU Leuven, Department of Human Genetics, Campus Gasthuisberg, 3000 Leuven, Belgium
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22
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Bergan J, Skotland T, Lingelem ABD, Simm R, Spilsberg B, Lindbäck T, Sylvänne T, Simolin H, Ekroos K, Sandvig K. The ether lipid precursor hexadecylglycerol protects against Shiga toxins. Cell Mol Life Sci 2014; 71:4285-300. [PMID: 24740796 PMCID: PMC11113769 DOI: 10.1007/s00018-014-1624-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Revised: 03/12/2014] [Accepted: 04/01/2014] [Indexed: 11/24/2022]
Abstract
Shiga toxin-producing Escherichia coli bacteria cause hemorrhagic colitis and hemolytic uremic syndrome in humans. Currently, only supportive treatment is available for diagnosed patients. We show here that 24-h pretreatment with an ether lipid precursor, the alkylglycerol sn-1-O-hexadecylglycerol (HG), protects HEp-2 cells against Shiga toxin and Shiga toxin 2. Also the endothelial cell lines HMEC-1 and HBMEC are protected against Shiga toxins after HG pretreatment. In contrast, the corresponding acylglycerol, DL-α-palmitin, has no effect on Shiga toxicity. Although HG treatment provides a strong protection (~30 times higher IC₅₀) against Shiga toxin, only a moderate reduction in toxin binding was observed, suggesting that retrograde transport of the toxin from the plasma membrane to the cytosol is perturbed. Furthermore, endocytosis of Shiga toxin and retrograde sorting from endosomes to the Golgi apparatus remain intact, but transport from the Golgi to the endoplasmic reticulum is inhibited by HG treatment. As previously described, HG reduces the total level of all quantified glycosphingolipids to 50-70% of control, including the Shiga toxin receptor globotriaosylceramide (Gb3), in HEp-2 cells. In accordance with this, we find that interfering with Gb3 biosynthesis by siRNA-mediated knockdown of Gb3 synthase for 24 h causes a similar cytotoxic protection and only a moderate reduction in toxin binding (to 70% of control cells). Alkylglycerols, including HG, have been administered to humans for investigation of therapeutic roles in disorders where ether lipid biosynthesis is deficient, as well as in cancer therapy. Further studies may reveal if HG can also have a therapeutic potential in Shiga toxin-producing E. coli infections.
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Affiliation(s)
- Jonas Bergan
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway
- Department of Biochemistry, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, 0379 Oslo, Norway
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, Oslo, Norway
| | - Tore Skotland
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway
- Department of Biochemistry, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, 0379 Oslo, Norway
| | - Anne Berit Dyve Lingelem
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway
- Department of Biochemistry, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, 0379 Oslo, Norway
| | - Roger Simm
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway
- Department of Biochemistry, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, 0379 Oslo, Norway
| | - Bjørn Spilsberg
- Section of Bacteriology-Food and GMO, Norwegian Veterinary Institute, Oslo, Norway
| | - Toril Lindbäck
- Department of Food Safety and Infection Biology, Norwegian School of Veterinary Science, Oslo, Norway
| | | | | | | | - Kirsten Sandvig
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway
- Department of Biochemistry, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, 0379 Oslo, Norway
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, Oslo, Norway
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23
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Martínez-Martínez N, Martínez-Alonso E, Ballesta J, Martínez-Menárguez JA. Phospholipase D2 is involved in the formation of Golgi tubules and ArfGAP1 recruitment. PLoS One 2014; 9:e111685. [PMID: 25354038 PMCID: PMC4213061 DOI: 10.1371/journal.pone.0111685] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 10/03/2014] [Indexed: 11/19/2022] Open
Abstract
Lipids and lipid-modifying enzymes play a key role in the biogenesis, maintenance and fission of transport carriers in the secretory and endocytic pathways. In the present study we demonstrate that phosphatidic acid generated by phospholipase D2 (PLD2) is involved in the formation of Golgi tubules. The main evidence to support this is: 1) inhibitors of phosphatidic acid formation and PLD2 depletion inhibit the formation of tubules containing resident enzymes and regulators of intra-Golgi transport in a low temperature (15°C) model of Golgi tubulation but do not affect brefeldin A-induced tubules, 2) inhibition of PLD2 enzymatic activity and PLD2 depletion in cells cultured under physiological conditions (37°C) induce the formation of tubules specifically containing Golgi matrix proteins, and, 3) over-expression of PLD2 induces the formation of a tubular network. In addition, it was found that the generation of this lipid by the isoenzyme is necessary for ArfGAP1 recruitment to Golgi membranes. These results suggest that both proteins are involved in the molecular mechanisms which drive the formation of different types of Golgi tubules.
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Affiliation(s)
- Narcisa Martínez-Martínez
- Department of Cell Biology and Histology, Medical School, IMIB-Arrixaca, University of Murcia, Murcia, Spain
| | - Emma Martínez-Alonso
- Department of Cell Biology and Histology, Medical School, IMIB-Arrixaca, University of Murcia, Murcia, Spain
| | - José Ballesta
- Department of Cell Biology and Histology, Medical School, IMIB-Arrixaca, University of Murcia, Murcia, Spain
| | - José A. Martínez-Menárguez
- Department of Cell Biology and Histology, Medical School, IMIB-Arrixaca, University of Murcia, Murcia, Spain
- * E-mail:
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24
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Morris AJ, Smyth SS. Lipid phosphate phosphatases: more than one way to put the brakes on LPA signaling? J Lipid Res 2014; 55:2195-7. [PMID: 25271297 DOI: 10.1194/jlr.c054957] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Affiliation(s)
- Andrew J Morris
- Division of Cardiovascular Medicine, University of Kentucky College of Medicine, Lexington Veterans Affairs Medical Center, Lexington, KY
| | - Susan S Smyth
- Division of Cardiovascular Medicine, University of Kentucky College of Medicine, Lexington Veterans Affairs Medical Center, Lexington, KY
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25
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Zanotti G, Cendron L. Structural and functional aspects of the Helicobacter pylori secretome. World J Gastroenterol 2014; 20:1402-1423. [PMID: 24587618 PMCID: PMC3925851 DOI: 10.3748/wjg.v20.i6.1402] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/28/2013] [Accepted: 01/06/2014] [Indexed: 02/06/2023] Open
Abstract
Proteins secreted by Helicobacter pylori (H. pylori), an important human pathogen responsible for severe gastric diseases, are reviewed from the point of view of their biochemical characterization, both functional and structural. Despite the vast amount of experimental data available on the proteins secreted by this bacterium, the precise size of the secretome remains unknown. In this review, we consider as secreted both proteins that contain a secretion signal for the periplasm and proteins that have been detected in the external medium in in vitro experiments. In this way, H. pylori’s secretome appears to be composed of slightly more than 160 proteins, but this number must be considered very cautiously, not only because the definition of secretome itself is ambiguous but also because the included proteins were observed as secreted in in vitro experiments that were not representative of the environmental situation in vivo. The proteins that appear to be secreted can be grouped into different classes: enzymes (48 proteins), outer membrane proteins (43), components of flagella (11), members of the cytotoxic-associated genes pathogenicity island or other toxins (8 and 5, respectively), binding and transport proteins (9), and others (11). A final group, which includes 28 members, is represented by hypothetical uncharacterized proteins. Despite the large amount of data accumulated on the H. pylori secretome, a considerable amount of work remains to reach a full comprehension of the system at the molecular level.
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26
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Sandvig K, Bergan J, Kavaliauskiene S, Skotland T. Lipid requirements for entry of protein toxins into cells. Prog Lipid Res 2014; 54:1-13. [PMID: 24462587 DOI: 10.1016/j.plipres.2014.01.001] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 01/15/2014] [Accepted: 01/15/2014] [Indexed: 01/05/2023]
Abstract
The plant toxin ricin and the bacterial toxin Shiga toxin both belong to a group of protein toxins having one moiety that binds to the cell surface, and another, enzymatically active moiety, that enters the cytosol and inhibits protein synthesis by inactivating ribosomes. Both toxins travel all the way from the cell surface to endosomes, the Golgi apparatus and the ER before the ribosome-inactivating moiety enters the cytosol. Shiga toxin binds to the neutral glycosphingolipid Gb3 at the cell surface and is therefore dependent on this lipid for transport into the cells, whereas ricin binds both glycoproteins and glycolipids with terminal galactose. The different steps of transport used by these toxins have specific requirements for lipid species, and with the recent developments in mass spectrometry analysis of lipids and microscopical and biochemical dissection of transport in cells, we are starting to see the complexity of endocytosis and intracellular transport. In this article we describe lipid requirements and the consequences of lipid changes for the entry and intoxication with ricin and Shiga toxin. These toxins can be a threat to human health, but can also be exploited for diagnosis and therapy, and have proven valuable as tools to study intracellular transport.
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Affiliation(s)
- Kirsten Sandvig
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway; Department of Biochemistry, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway; Department of Biosciences, University of Oslo, Oslo, Norway.
| | - Jonas Bergan
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway; Department of Biochemistry, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway.
| | - Simona Kavaliauskiene
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway; Department of Biochemistry, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway; Department of Biosciences, University of Oslo, Oslo, Norway.
| | - Tore Skotland
- Centre for Cancer Biomedicine, Faculty of Medicine, University of Oslo, Oslo, Norway; Department of Biochemistry, Institute for Cancer Research, The Norwegian Radium Hospital, Oslo University Hospital, Oslo, Norway.
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27
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Martínez-Alonso E, Tomás M, Martínez-Menárguez JA. Golgi tubules: their structure, formation and role in intra-Golgi transport. Histochem Cell Biol 2013; 140:327-39. [PMID: 23812035 DOI: 10.1007/s00418-013-1114-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/16/2013] [Indexed: 11/28/2022]
Abstract
Tubules are common Golgi elements that can form extensive networks associated with the cis-, lateral and trans-Golgi sides, but despite this, they have almost been forgotten for decades. The molecular mechanisms involved in their formation, elongation and fission are only just beginning to be understood. However, the role of these membranes is not well understood. In the present review, we analyze the mechanisms that induce Golgi tubulation or, conversely, disrupt tubules in order to throw some lights on the nature of these elements. The putative role of these elements in the framework of current models for intra-Golgi transport is also discussed.
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Affiliation(s)
- Emma Martínez-Alonso
- Department of Cell Biology and Histology, Medical School, University of Murcia, 30100 Murcia, Spain
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