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Ellson CD, Goretti Riça I, Kim JS, Huang YMM, Lim D, Mitra T, Hsu A, Wei EX, Barrett CD, Wahl M, Delbrück H, Heinemann U, Oschkinat H, Chang CEA, Yaffe MB. An integrated pharmacological, structural, and genetic analysis of extracellular versus intracellular ROS production in neutrophils. J Mol Biol 2022; 434:167533. [DOI: 10.1016/j.jmb.2022.167533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 03/03/2022] [Indexed: 11/28/2022]
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Chang YC, Chang PMH, Li CH, Chan MH, Lee YJ, Chen MH, Hsiao M. Aldolase A and Phospholipase D1 Synergistically Resist Alkylating Agents and Radiation in Lung Cancer. Front Oncol 2022; 11:811635. [PMID: 35127525 PMCID: PMC8813753 DOI: 10.3389/fonc.2021.811635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 12/27/2021] [Indexed: 11/13/2022] Open
Abstract
Exposure to alkylating agents and radiation may cause damage and apoptosis in cancer cells. Meanwhile, this exposure involves resistance and leads to metabolic reprogramming to benefit cancer cells. At present, the detailed mechanism is still unclear. Based on the profiles of several transcriptomes, we found that the activity of phospholipase D (PLD) and the production of specific metabolites are related to these events. Comparing several particular inhibitors, we determined that phospholipase D1 (PLD1) plays a dominant role over other PLD members. Using the existing metabolomics platform, we demonstrated that lysophosphatidylethanolamine (LPE) and lysophosphatidylcholine (LPC) are the most critical metabolites, and are highly dependent on aldolase A (ALDOA). We further demonstrated that ALDOA could modulate total PLD enzyme activity and phosphatidic acid products. Particularly after exposure to alkylating agents and radiation, the proliferation of lung cancer cells, autophagy, and DNA repair capabilities are enhanced. The above phenotypes are closely related to the performance of the ALDOA/PLD1 axis. Moreover, we found that ALDOA inhibited PLD2 activity and enzyme function through direct protein–protein interaction (PPI) with PLD2 to enhance PLD1 and additional carcinogenic features. Most importantly, the combination of ALDOA and PLD1 can be used as an independent prognostic factor and is correlated with several clinical parameters in lung cancer. These findings indicate that, based on the PPI status between ALDOA and PLD2, a combination of radiation and/or alkylating agents with regulating ALDOA-PLD1 may be considered as a new lung cancer treatment option.
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Affiliation(s)
- Yu-Chan Chang
- Department of Biomedical Imaging and Radiological Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Peter Mu-Hsin Chang
- Department of Oncology, Taipei Veterans General Hospital, Taipei, Taiwan
- Faculty of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
- Institute of Biopharmaceutical Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Chien-Hsiu Li
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
| | | | - Yi-Jang Lee
- Department of Biomedical Imaging and Radiological Sciences, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Ming-Huang Chen
- Faculty of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
- Center of Immuno-Oncology, Department of Oncology, Taipei Veterans General Hospital, Taipei, Taiwan
| | - Michael Hsiao
- Genomics Research Center, Academia Sinica, Taipei, Taiwan
- Department of Biochemistry, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
- *Correspondence: Michael Hsiao,
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Cai M, Wang Z, Luu TTT, Zhang D, Finke B, He J, Tay LWR, Di Paolo G, Du G. PLD1 promotes reactive oxygen species production in vascular smooth muscle cells and injury-induced neointima formation. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1867:159062. [PMID: 34610470 DOI: 10.1016/j.bbalip.2021.159062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 08/28/2021] [Accepted: 08/31/2021] [Indexed: 10/20/2022]
Abstract
Phospholipase D (PLD) generates the signaling lipid phosphatidic acid (PA) and has been known to mediate proliferation signal in vascular smooth muscle cells (VSMCs). However, it remains unclear how PLD contributes to vascular diseases. VSMC proliferation directly contributes to the development and progression of cardiovascular disease, such as atherosclerosis and restenosis after angioplasty. Using the mouse carotid artery ligation model, we find that deletion of Pld1 gene inhibits neointima formation of the injuried blood vessels. PLD1 deficiency reduces the proliferation of VSMCs in both injured artery and primary cultures through the inhibition of ERK1/2 and AKT signals. Immunohistochemical staining of injured artery and flow cytometry analysis of VSMCs shows a reduction of the levels of reactive oxygen species (ROS) in Pld1-/- VSMCs. An increase of intracellular ROS by hydrogen peroxide stimulation restored the reduced activities of ERK and AKT in Pld1-/- VSMCs, whereas a reduction of ROS by N-acetyl-l-cysteine (NAC) scavenger lowered their activity in wild-type VSMCs. These results indicate that PLD1 plays a critical role in neointima, and that PLD1 mediates VSMC proliferation signal through promoting the production of ROS. Therefore, inhibition of PLD1 may be used as a therapeutic approach to suppress neointimal formation in atherosclerosis and restenosis after angioplasty.
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Affiliation(s)
- Ming Cai
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA; Department of Gastrointestinal Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, Hubei Province, China
| | - Ziqing Wang
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Thi Thu Trang Luu
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA; Biochemistry and Cell Biology Program, MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, Houston, TX 77030, USA
| | - Dakai Zhang
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Brian Finke
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Jingquan He
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Li Wei Rachel Tay
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Gilbert Di Paolo
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032, USA
| | - Guangwei Du
- Department of Integrative Biology and Pharmacology, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA.
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Fernández-Medarde A, Santos E. Ras GEF Mouse Models for the Analysis of Ras Biology and Signaling. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2021; 2262:361-395. [PMID: 33977490 DOI: 10.1007/978-1-0716-1190-6_23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Animal models have become in recent years a crucial tool to understand the physiological and pathological roles of many cellular proteins. They allow analysis of the functional consequences of [1] complete or partial (time- or organ-limited) removal of specific proteins (knockout animals), [2] the exchange of a wild-type allele for a mutant or truncated version found in human illnesses (knock-in), or [3] the effect of overexpression of a given protein in the whole body or in specific organs (transgenic mice). In this regard, the study of phenotypes in Ras GEF animal models has allowed researchers to find specific functions for otherwise very similar proteins, uncovering their role in physiological contexts such as memory formation, lymphopoiesis, photoreception, or body homeostasis. In addition, mouse models have been used to unveil the functional role of Ras GEFs under pathological conditions, including Noonan syndrome, skin tumorigenesis, inflammatory diseases, diabetes, or ischemia among others. In the following sections, we will describe the methodological approaches employed for Ras GEF animal model analyses, as well as the main discoveries made.
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Affiliation(s)
- Alberto Fernández-Medarde
- Centro de Investigación del Cáncer-Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca) and CIBERONC, Salamanca, Spain.
| | - Eugenio Santos
- Centro de Investigación del Cáncer-Instituto de Biología Molecular y Celular del Cáncer (CSIC-Universidad de Salamanca) and CIBERONC, Salamanca, Spain
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Santa-Marinha L, Castanho I, Silva RR, Bravo FV, Miranda AM, Meira T, Morais-Ribeiro R, Marques F, Xu Y, Point du Jour K, Wenk M, Chan RB, Di Paolo G, Pinto V, Oliveira TG. Phospholipase D1 Ablation Disrupts Mouse Longitudinal Hippocampal Axis Organization and Functioning. Cell Rep 2021; 30:4197-4208.e6. [PMID: 32209478 DOI: 10.1016/j.celrep.2020.02.102] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Revised: 01/29/2020] [Accepted: 02/27/2020] [Indexed: 01/01/2023] Open
Abstract
Phosphatidic acid (PA) is a signaling lipid involved in the modulation of synaptic structure and functioning. Based on previous work showing a decreasing PA gradient along the longitudinal axis of the rodent hippocampus, we asked whether the dorsal hippocampus (DH) and the ventral hippocampus (VH) are differentially affected by PA modulation. Here, we show that phospholipase D1 (PLD1) is a major hippocampal PA source, compared to PLD2, and that PLD1 ablation affects predominantly the lipidome of the DH. Moreover, Pld1 knockout (KO) mice show specific deficits in novel object recognition and social interaction and disruption in the DH-VH dendritic arborization differentiation in CA1/CA3 pyramidal neurons. Also, Pld1 KO animals present reduced long-term depression (LTD) induction and reduced GluN2A and SNAP-25 protein levels in the DH. Overall, we observe that PLD1-derived PA reduction leads to differential lipid signatures along the longitudinal hippocampal axis, predominantly affecting DH organization and functioning.
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Affiliation(s)
- Luísa Santa-Marinha
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Isabel Castanho
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Rita Ribeiro Silva
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Francisca Vaz Bravo
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - André Miguel Miranda
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Torcato Meira
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Rafaela Morais-Ribeiro
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Fernanda Marques
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Yimeng Xu
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032, USA
| | - Kimberly Point du Jour
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032, USA; Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY 10032, USA
| | - Markus Wenk
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 117596, Singapore
| | - Robin Barry Chan
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032, USA; Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY 10032, USA
| | - Gilbert Di Paolo
- Department of Pathology and Cell Biology, Columbia University Medical Center, New York, NY 10032, USA; Taub Institute for Research on Alzheimer's Disease and the Aging Brain, Columbia University Medical Center, New York, NY 10032, USA
| | - Vítor Pinto
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal
| | - Tiago Gil Oliveira
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Campus Gualtar, 4710-057 Braga, Portugal; ICVS/3B's - PT Government Associate Laboratory, Braga/Guimarães, Portugal.
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Borel M, Cuvillier O, Magne D, Mebarek S, Brizuela L. Increased phospholipase D activity contributes to tumorigenesis in prostate cancer cell models. Mol Cell Biochem 2020; 473:263-279. [PMID: 32661773 DOI: 10.1007/s11010-020-03827-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Accepted: 07/04/2020] [Indexed: 12/30/2022]
Abstract
Prostate cancer (PCa) is the most frequent cancer among men and the first cause of death over 65. Approximately 90% of patients with advanced disease will develop bone metastasis, which dramatically reduces long-term survival. Therefore, effective therapies need to be developed, especially when disease is still well-localized. Phospholipase D (PLD), an enzyme that hydrolyzes phosphatidylcholine to yield phosphatidic acid, regulates several cellular functions as proliferation, survival, migration or vesicular trafficking. PLD is implicated in numerous diseases such as neurodegenerative, cardiovascular, autoimmune disorders or cancer. Indeed, PLD controls different aspects of oncogenesis including tumor progression and resistance to targeted therapies such as radiotherapy. PLD1 and PLD2 are the only isoforms with catalytic activity involved in cancer. Surprisingly, studies deciphering the role of PLD in the pathophysiology of PCa are scarce. Here we describe the correlation between PLD activity and PLD1 and PLD2 expression in PCa bone metastasis-derived cell lines C4-2B and PC-3. Next, by using PLD pharmacological inhibitors and RNA interference strategy, we validate the implication of PLD1 and PLD2 in cell viability, clonogenicity and proliferation of C4-2B and PC-3 cells and in migration capacity of PC-3 cells. Last, we show an increase in PLD activity as well as PLD2 protein expression during controlled starvation of PC-3 cells, concomitant with an augmentation of its migration capacity. Specifically, upregulation of PLD activity appears to be PKC-independent. Taken together, our results indicate that PLD, and in particular PLD2, could be considered as a potential therapeutic target for the treatment of PCa-derived bone metastasis.
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Affiliation(s)
- Mathieu Borel
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS UMR 5246, ICBMS, 69622, Lyon, France
| | - Olivier Cuvillier
- Université de Toulouse, UPS, CNRS UMR 5089, Institut de Pharmacologie et de Biologie Structurale, IPBS, 31077, Toulouse Cedex, France
| | - David Magne
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS UMR 5246, ICBMS, 69622, Lyon, France
| | - Saida Mebarek
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS UMR 5246, ICBMS, 69622, Lyon, France
| | - Leyre Brizuela
- Univ Lyon, Université Claude Bernard Lyon 1, CNRS UMR 5246, ICBMS, 69622, Lyon, France.
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Frias MA, Mukhopadhyay S, Lehman E, Walasek A, Utter M, Menon D, Foster DA. Phosphatidic acid drives mTORC1 lysosomal translocation in the absence of amino acids. J Biol Chem 2020; 295:263-274. [PMID: 31767684 PMCID: PMC6952608 DOI: 10.1074/jbc.ra119.010892] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Revised: 11/14/2019] [Indexed: 01/30/2023] Open
Abstract
Mammalian target of rapamycin complex 1 (mTORC1) promotes cell growth and proliferation in response to nutrients and growth factors. Amino acids induce lysosomal translocation of mTORC1 via the Rag GTPases. Growth factors activate Ras homolog enriched in brain (Rheb), which in turn activates mTORC1 at the lysosome. Amino acids and growth factors also induce the phospholipase D (PLD)-phosphatidic acid (PA) pathway, required for mTORC1 signaling through mechanisms that are not fully understood. Here, using human and murine cell lines, along with immunofluorescence, confocal microscopy, endocytosis, PLD activity, and cell viability assays, we show that exogenously supplied PA vesicles deliver mTORC1 to the lysosome in the absence of amino acids, Rag GTPases, growth factors, and Rheb. Of note, pharmacological or genetic inhibition of endogenous PLD prevented mTORC1 lysosomal translocation. We observed that precancerous cells with constitutive Rheb activation through loss of tuberous sclerosis complex subunit 2 (TSC2) exploit the PLD-PA pathway and thereby sustain mTORC1 activation at the lysosome in the absence of amino acids. Our findings indicate that sequential inputs from amino acids and growth factors trigger PA production required for mTORC1 translocation and activation at the lysosome.
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Affiliation(s)
- Maria A Frias
- Department of Biological Sciences, Hunter College of the City University of New York, New York, New York 10021; Clinical and Translational Master's Program, Clinical and Translational Science Center, Weill Cornell Medicine, New York, New York 10065.
| | - Suman Mukhopadhyay
- Department of Biological Sciences, Hunter College of the City University of New York, New York, New York 10021
| | - Elyssa Lehman
- Department of Biological Sciences, Hunter College of the City University of New York, New York, New York 10021
| | - Aleksandra Walasek
- Department of Biological Sciences, Hunter College of the City University of New York, New York, New York 10021
| | - Matthew Utter
- Department of Biological Sciences, Hunter College of the City University of New York, New York, New York 10021
| | - Deepak Menon
- Department of Biological Sciences, Hunter College of the City University of New York, New York, New York 10021
| | - David A Foster
- Department of Biological Sciences, Hunter College of the City University of New York, New York, New York 10021; Department of Pharmacology, Weill Cornell Medicine, New York, New York 10065.
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McDermott MI, Wang Y, Wakelam MJO, Bankaitis VA. Mammalian phospholipase D: Function, and therapeutics. Prog Lipid Res 2019; 78:101018. [PMID: 31830503 DOI: 10.1016/j.plipres.2019.101018] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 10/08/2019] [Accepted: 10/14/2019] [Indexed: 01/23/2023]
Abstract
Despite being discovered over 60 years ago, the precise role of phospholipase D (PLD) is still being elucidated. PLD enzymes catalyze the hydrolysis of the phosphodiester bond of glycerophospholipids producing phosphatidic acid and the free headgroup. PLD family members are found in organisms ranging from viruses, and bacteria to plants, and mammals. They display a range of substrate specificities, are regulated by a diverse range of molecules, and have been implicated in a broad range of cellular processes including receptor signaling, cytoskeletal regulation and membrane trafficking. Recent technological advances including: the development of PLD knockout mice, isoform-specific antibodies, and specific inhibitors are finally permitting a thorough analysis of the in vivo role of mammalian PLDs. These studies are facilitating increased recognition of PLD's role in disease states including cancers and Alzheimer's disease, offering potential as a target for therapeutic intervention.
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Affiliation(s)
- M I McDermott
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX 77843-1114, United States of America.
| | - Y Wang
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX 77843-1114, United States of America; Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843-2128, United States of America
| | - M J O Wakelam
- Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, United Kingdom
| | - V A Bankaitis
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX 77843-1114, United States of America; Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas 77843-2128, United States of America; Department of Chemistry, Texas A&M University, College Station, Texas 77840, United States of America
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Ramenskaia GV, Melnik EV, Petukhov AE. [Phospholipase D: its role in metabolism processes and disease development]. BIOMEDIT︠S︡INSKAI︠A︡ KHIMII︠A︡ 2019; 64:84-93. [PMID: 29460838 DOI: 10.18097/pbmc20186401084] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Phospholipase D (PLD) is one of the key enzymes that catalyzes the hydrolysis of cell membrane phospholipids. In this review current knowledge about six human PLD isoforms, their structure and role in physiological and pathological processes is summarized. Comparative analysis of PLD isoforms structure is presented. The mechanism of the hydrolysis and transphosphatidylation performed by PLD is described. The PLD1 and PLD2 role in the pathogenesis of some cancer, infectious, thrombotic and neurodegenerative diseases is analyzed. The prospects of PLD isoform-selective inhibitors development are shown in the context of the clinical usage and the already-existing inhibitors are characterized. Moreover, the formation of phosphatidylethanol (PEth), the alcohol abuse biomarker, as the result of PLD-catalyzed phospholipid transphosphatidylation is considered.
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Affiliation(s)
- G V Ramenskaia
- Sechenov First Moscow State Medical University (Sechenovskiy University), Moscow, Russia
| | - E V Melnik
- Sechenov First Moscow State Medical University (Sechenovskiy University), Moscow, Russia
| | - A E Petukhov
- Sechenov First Moscow State Medical University (Sechenovskiy University), Moscow, Russia; Moscow Research and Practical Centre for Narcology, Moscow, Russia
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The function of TRP channels in neutrophil granulocytes. Pflugers Arch 2018; 470:1017-1033. [PMID: 29717355 DOI: 10.1007/s00424-018-2146-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 04/09/2018] [Accepted: 04/13/2018] [Indexed: 02/07/2023]
Abstract
Neutrophil granulocytes are exposed to widely varying microenvironmental conditions when pursuing their physiological or pathophysiological functions such as fighting invading bacteria or infiltrating cancer tissue. Examples for harsh environmental challenges include among others mechanical shear stress during the recruitment from the vasculature or the hypoxic and acidotic conditions within the tumor microenvironment. Chemokine gradients, reactive oxygen species, pressure, matrix elasticity, and temperature can be added to the list of potential challenges. Transient receptor potential (TRP) channels serve as cellular sensors since they respond to many of the abovementioned environmental stimuli. The present review investigates the role of TRP channels in neutrophil granulocytes and their role in regulating and adapting neutrophil function to microenvironmental cues. Following a brief description of neutrophil functions, we provide an overview of the electrophysiological characterization of neutrophilic ion channels. We then summarize the function of individual TRP channels in neutrophil granulocytes with a focus on TRPC6 and TRPM2 channels. We close the review by discussing the impact of the tumor microenvironment of pancreatic ductal adenocarcinoma (PDAC) on neutrophil granulocytes. Since neutrophil infiltration into PDAC tissue contributes to disease progression, we propose neutrophilic TRP channel blockade as a potential therapeutic option.
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O'Donnell VB, Rossjohn J, Wakelam MJ. Phospholipid signaling in innate immune cells. J Clin Invest 2018; 128:2670-2679. [PMID: 29683435 DOI: 10.1172/jci97944] [Citation(s) in RCA: 54] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Phospholipids comprise a large body of lipids that define cells and organelles by forming membrane structures. Importantly, their complex metabolism represents a highly controlled cellular signaling network that is essential for mounting an effective innate immune response. Phospholipids in innate cells are subject to dynamic regulation by enzymes, whose activities are highly responsive to activation status. Along with their metabolic products, they regulate multiple aspects of innate immune cell biology, including shape change, aggregation, blood clotting, and degranulation. Phospholipid hydrolysis provides substrates for cell-cell communication, enables regulation of hemostasis, immunity, thrombosis, and vascular inflammation, and is centrally important in cardiovascular disease and associated comorbidities. Phospholipids themselves are also recognized by innate-like T cells, which are considered essential for recognition of infection or cancer, as well as self-antigens. This Review describes the major phospholipid metabolic pathways present in innate immune cells and summarizes the formation and metabolism of phospholipids as well as their emerging roles in cell biology and disease.
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Affiliation(s)
- Valerie B O'Donnell
- Systems Immunity Research Institute and Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom
| | - Jamie Rossjohn
- Systems Immunity Research Institute and Division of Infection and Immunity, School of Medicine, Cardiff University, Cardiff, United Kingdom.,Infection and Immunity Program and Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, and.,ARC Centre of Excellence in Advanced Molecular Imaging, Monash University, Clayton, Victoria, Australia
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12
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Abstract
Phospholipase D (PLD) enzymes are one source of receptor-generated phosphatidic acid (PtdOH),which may subsequently be metabolized to diacylglycerol (DAG) and lysophosphatidic acid. There are other pathways that lead to PtdOH generation, but differences in pathways and in the acyl composition of the products seem to provide some specificity. Both direct and indirect inhibitors of PLD activity have been identified despite a long-held suspicion that this pathway was undruggable. The identification of raloxifene and halopemide as direct inhibitors was followed by the systematic development of isoenzyme-preferring compounds that have been used to further differentiate the functions of PLD1 and PLD2. PLD2 in host cells has been associated with viral entry processes and innate immune response pathways such that inhibition blocks efficient infection. This PLD2 pathway has been linked to autophagy via AKT kinases. As a potential target in antiretroviral therapy, PLD1 works through the CAD enzyme (which contains carbamoyl aspartate synthase, aspartate transcarbamylase and dihydro-orotase domains) to modulate pyrimidine biosynthesis. PLD activity and expression have been shown to be upregulated in several types of human cancers, in which PLD enzymes function downstream of a variety of known oncogenes. Inhibition of PtdOH production has a marked effect on tumorigenesis and malignant invasion. PLD1, PLD2 and PLD3 have each been suggested to have a role in Alzheimer disease and other neurodegenerative conditions, but a mechanism has not yet emerged to explain the roles of these proteins in central nervous system pathophysiology.
Lipid second messengers such as phosphatidic acid (PtdOH) have a role in a wide range of pathological processes, and phospholipase D (PLD) enzymes are one of the major sources of signal-activated PtdOH generation. In this Review, Brown, Thomas and Lindsley discuss the development of PLD inhibitors, with a focus on isoform-specific inhibitors, and their potential applications in the treatment of cancer, neurodegeneration and infection. Lipid second messengers have essential roles in cellular function and contribute to the molecular mechanisms that underlie inflammation, malignant transformation, invasiveness, neurodegenerative disorders, and infectious and other pathophysiological processes. The phospholipase D (PLD) isoenzymes PLD1 and PLD2 are one of the major sources of signal-activated phosphatidic acid (PtdOH) generation downstream of a variety of cell-surface receptors, including G protein-coupled receptors (GPCRs), receptor tyrosine kinases (RTKs) and integrins. Recent advances in the development of isoenzyme-selective PLD inhibitors and in molecular genetics have suggested that PLD isoenzymes in mammalian cells and pathogenic organisms may be valuable targets for the treatment of several human diseases. Isoenzyme-selective inhibitors have revealed complex inter-relationships between PtdOH biosynthetic pathways and the role of PtdOH in pathophysiology. PLD enzymes were once thought to be undruggable owing to the ubiquitous nature of PtdOH in cell signalling and concerns that inhibitors would be too toxic for use in humans. However, recent promising discoveries suggest that small-molecule isoenzyme-selective inhibitors may provide novel compounds for a unique approach to the treatment of cancers, neurodegenerative disorders and other afflictions of the central nervous system, and potentially serve as broad-spectrum antiviral and antimicrobial therapeutics.
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The Phospholipase D2 Knock Out Mouse Has Ectopic Purkinje Cells and Suffers from Early Adult-Onset Anosmia. PLoS One 2016; 11:e0162814. [PMID: 27658289 PMCID: PMC5033577 DOI: 10.1371/journal.pone.0162814] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 08/29/2016] [Indexed: 11/25/2022] Open
Abstract
Phospholipase D2 (PLD2) is an enzyme that produces phosphatidic acid (PA), a lipid messenger molecule involved in a number of cellular events including, through its membrane curvature properties, endocytosis. The PLD2 knock out (PLD2KO) mouse has been previously reported to be protected from insult in a model of Alzheimer's disease. We have further analysed a PLD2KO mouse using mass spectrophotometry of its lipids and found significant differences in PA species throughout its brain. We have examined the expression pattern of PLD2 which allowed us to define which region of the brain to analyse for defect, notably PLD2 was not detected in glial-rich regions. The expression pattern lead us to specifically examine the mitral cells of olfactory bulbs, the Cornus Amonis (CA) regions of the hippocampus and the Purkinje cells of the cerebellum. We find that the change to longer PA species correlates with subtle architectural defect in the cerebellum, exemplified by ectopic Purkinje cells and an adult-onset deficit of olfaction. These observations draw parallels to defects in the reelin heterozygote as well as the effect of high fat diet on olfaction.
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14
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A data-driven network model of primary myelofibrosis: transcriptional and post-transcriptional alterations in CD34+ cells. Blood Cancer J 2016; 6:e439. [PMID: 27341078 PMCID: PMC5141361 DOI: 10.1038/bcj.2016.47] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 05/19/2016] [Indexed: 12/18/2022] Open
Abstract
microRNAs (miRNAs) are relevant in the pathogenesis of primary myelofibrosis (PMF) but our understanding is limited to specific target genes and the overall systemic scenario islacking. By both knowledge-based and ab initio approaches for comparative analysis of CD34+ cells of PMF patients and healthy controls, we identified the deregulated pathways involving miRNAs and genes and new transcriptional and post-transcriptional regulatory circuits in PMF cells. These converge in a unique and integrated cellular process, in which the role of specific miRNAs is to wire, co-regulate and allow a fine crosstalk between the involved processes. The PMF pathway includes Akt signaling, linked to Rho GTPases, CDC42, PLD2, PTEN crosstalk with the hypoxia response and Calcium-linked cellular processes connected to cyclic AMP signaling. Nested on the depicted transcriptional scenario, predicted circuits are reported, opening new hypotheses. Links between miRNAs (miR-106a-5p, miR-20b-5p, miR-20a-5p, miR-17-5p, miR-19b-3p and let-7d-5p) and key transcription factors (MYCN, ATF, CEBPA, REL, IRF and FOXJ2) and their common target genes tantalizingly suggest new path to approach the disease. The study provides a global overview of transcriptional and post-transcriptional deregulations in PMF, and, unifying consolidated and predicted data, could be helpful to identify new combinatorial therapeutic strategy. Interactive PMF network model: http://compgen.bio.unipd.it/pmf-net/.
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15
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Diz-Muñoz A, Thurley K, Chintamen S, Altschuler SJ, Wu LF, Fletcher DA, Weiner OD. Membrane Tension Acts Through PLD2 and mTORC2 to Limit Actin Network Assembly During Neutrophil Migration. PLoS Biol 2016; 14:e1002474. [PMID: 27280401 PMCID: PMC4900667 DOI: 10.1371/journal.pbio.1002474] [Citation(s) in RCA: 126] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Accepted: 05/04/2016] [Indexed: 11/18/2022] Open
Abstract
For efficient polarity and migration, cells need to regulate the magnitude and spatial distribution of actin assembly. This process is coordinated by reciprocal interactions between the actin cytoskeleton and mechanical forces. Actin polymerization-based protrusion increases tension in the plasma membrane, which in turn acts as a long-range inhibitor of actin assembly. These interactions form a negative feedback circuit that limits the magnitude of membrane tension in neutrophils and prevents expansion of the existing front and the formation of secondary fronts. It has been suggested that the plasma membrane directly inhibits actin assembly by serving as a physical barrier that opposes protrusion. Here we show that efficient control of actin polymerization-based protrusion requires an additional mechanosensory feedback cascade that indirectly links membrane tension with actin assembly. Specifically, elevated membrane tension acts through phospholipase D2 (PLD2) and the mammalian target of rapamycin complex 2 (mTORC2) to limit actin nucleation. In the absence of this pathway, neutrophils exhibit larger leading edges, higher membrane tension, and profoundly defective chemotaxis. Mathematical modeling suggests roles for both the direct (mechanical) and indirect (biochemical via PLD2 and mTORC2) feedback loops in organizing cell polarity and motility—the indirect loop is better suited to enable competition between fronts, whereas the direct loop helps spatially organize actin nucleation for efficient leading edge formation and cell movement. This circuit is essential for polarity, motility, and the control of membrane tension. A mechanosensory biochemical cascade involving phospholipase D2 and mTORC2 coordinates physical forces and cytoskeletal rearrangements to allow efficient polarization and migration of neutrophils. How cells regulate the size and number of their protrusions for efficient polarity and motility is a fundamental question in cell biology. We recently found that immune cells known as neutrophils use physical forces to regulate this process. Actin polymerization-based protrusion stretches the plasma membrane, and this increased membrane tension acts as a long-range inhibitor of actin-based protrusions elsewhere in the cell. Here we investigate how membrane tension limits protrusion. We demonstrate that the magnitude of actin network assembly in neutrophils is determined by a mechanosensory biochemical cascade that converts increases in membrane tension into decreases in protrusion. Specifically, we show that increasing plasma membrane tension acts through a pathway containing the phospholipase D2 (PLD2) and the mammalian target of rapamycin complex 2 (mTORC2) to limit actin network assembly. Without this negative feedback pathway, neutrophils exhibit larger leading edges, higher membrane tension, and profoundly defective chemotaxis. Mathematical modeling indicates that this feedback circuit is a favorable topology to enable competition between protrusions during neutrophil polarization. Our work shows how biochemical signals, physical forces, and the cytoskeleton can collaborate to generate large-scale cellular organization.
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Affiliation(s)
- Alba Diz-Muñoz
- Cardiovascular Research Institute and Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California, United States of America
- Bioengineering Department and Biophysics Program, University of California Berkeley, Berkeley, California, United States of America
| | - Kevin Thurley
- Dept. of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, California, United States of America
| | - Sana Chintamen
- Cardiovascular Research Institute and Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California, United States of America
| | - Steven J. Altschuler
- Dept. of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, California, United States of America
| | - Lani F. Wu
- Dept. of Pharmaceutical Chemistry, University of California San Francisco, San Francisco, California, United States of America
| | - Daniel A. Fletcher
- Bioengineering Department and Biophysics Program, University of California Berkeley, Berkeley, California, United States of America
- * E-mail: (DAF); (ODW)
| | - Orion D. Weiner
- Cardiovascular Research Institute and Department of Biochemistry and Biophysics, University of California San Francisco, San Francisco, California, United States of America
- * E-mail: (DAF); (ODW)
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16
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Ghim J, Chelakkot C, Bae YS, Suh PG, Ryu SH. Accumulating insights into the role of phospholipase D2 in human diseases. Adv Biol Regul 2016; 61:42-46. [PMID: 26695710 DOI: 10.1016/j.jbior.2015.11.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2015] [Revised: 11/27/2015] [Accepted: 11/27/2015] [Indexed: 06/05/2023]
Abstract
Phospholipase D2 (PLD2) is a lipid-signaling enzyme that produces the signaling molecule phosphatidic acid (PA) by catalyzing the hydrolysis of phosphatidylcholine (PC). The molecular characteristics of PLD2, the mechanisms of regulation of its activity, its functions in the signaling pathway involving PA and binding partners, and its role in cellular physiology have been extensively studied over the past decades. Although several potential roles of PLD2 have been proposed based on the results of molecular and cell-based studies, the pathophysiological functions of PLD2 in vivo have not yet been fully investigated at the organismal level. Here, we address accumulated evidences that provide insight into the role of PLD2 in human disease. We summarize recent studies using animal models that provide direct evidence of the function of PLD2 in several pathological conditions such as vascular disease, immunological disease, and neurological disease. In light of the use of recently developed PLD2-specific inhibitors showing potential in alleviating pathological conditions, improving our understanding of the role of PLD2 in human disease would be necessary to target the regulation of PLD2 activity as a therapeutic strategy.
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Affiliation(s)
- Jaewang Ghim
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Republic of Korea
| | - Chaithanya Chelakkot
- Division of Integrative Biosciences and Biotechnology, Pohang University of Science and Technology, Pohang, Republic of Korea
| | - Yoe-Sik Bae
- Department of Biological Sciences, Sungkyunkwan University, Suwon, Republic of Korea
| | - Pann-Ghill Suh
- School of Life Sciences, Ulsan National Institute of Science and Technology, Ulsan, Republic of Korea
| | - Sung Ho Ryu
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, Republic of Korea.
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17
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Role of phospholipases D1 and 2 in astroglial proliferation: effects of specific inhibitors and genetic deletion. Eur J Pharmacol 2015; 761:398-404. [DOI: 10.1016/j.ejphar.2015.05.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 04/11/2015] [Accepted: 05/08/2015] [Indexed: 01/08/2023]
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18
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Dibble CC, Cantley LC. Regulation of mTORC1 by PI3K signaling. Trends Cell Biol 2015; 25:545-55. [PMID: 26159692 DOI: 10.1016/j.tcb.2015.06.002] [Citation(s) in RCA: 536] [Impact Index Per Article: 59.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Revised: 06/08/2015] [Accepted: 06/08/2015] [Indexed: 11/29/2022]
Abstract
The class I phosphoinositide 3-kinase (PI3K)-mechanistic target of rapamycin (mTOR) complex 1 (mTORC1) signaling network directs cellular metabolism and growth. Activation of mTORC1 [composed of mTOR, regulatory-associated protein of mTOR (Raptor), mammalian lethal with SEC13 protein 8(mLST8), 40-kDa proline-rich Akt substrate (PRAS40), and DEP domain-containing mTOR-interacting protein (DEPTOR)] depends on the Ras-related GTPases (Rags) and Ras homolog enriched in brain (Rheb) GTPase and requires signals from amino acids, glucose, oxygen, energy (ATP), and growth factors (including cytokines and hormones such as insulin). Here we discuss the signal transduction mechanisms through which growth factor-responsive PI3K signaling activates mTORC1. We focus on how PI3K-dependent activation of Akt and spatial regulation of the tuberous sclerosis complex (TSC) complex (TSC complex) [composed of TSC1, TSC2, and Tre2-Bub2-Cdc16-1 domain family member 7 (TBC1D7)] switches on Rheb at the lysosome, where mTORC1 is activated. Integration of PI3K- and amino acid-dependent signals upstream of mTORC1 at the lysosome is detailed in a working model. A coherent understanding of the PI3K-mTORC1 network is imperative as its dysregulation has been implicated in diverse pathologies including cancer, diabetes, autism, and aging.
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Affiliation(s)
- Christian C Dibble
- Department of Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Lewis C Cantley
- Meyer Cancer Center, Department of Medicine, Weill Cornell Medical College, New York, NY 10065, USA.
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19
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Speed and sensitivity of phototransduction in Drosophila depend on degree of saturation of membrane phospholipids. J Neurosci 2015; 35:2731-46. [PMID: 25673862 DOI: 10.1523/jneurosci.1150-14.2015] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Drosophila phototransduction is mediated via a G-protein-coupled PLC cascade. Recent evidence, including the demonstration that light evokes rapid contractions of the photoreceptors, suggested that the light-sensitive channels (TRP and TRPL) may be mechanically gated, together with protons released by PLC-mediated PIP2 hydrolysis. If mechanical gating is involved we predicted that the response to light should be influenced by altering the physical properties of the membrane. To achieve this, we used diet to manipulate the degree of saturation of membrane phospholipids. In flies reared on a yeast diet, lacking polyunsaturated fatty acids (PUFAs), mass spectrometry showed that the proportion of polyunsaturated phospholipids was sevenfold reduced (from 38 to ∼5%) but rescued by adding a single species of PUFA (linolenic or linoleic acid) to the diet. Photoreceptors from yeast-reared flies showed a 2- to 3-fold increase in latency and time to peak of the light response, without affecting quantum bump waveform. In the absence of Ca(2+) influx or in trp mutants expressing only TRPL channels, sensitivity to light was reduced up to ∼10-fold by the yeast diet, and essentially abolished in hypomorphic G-protein mutants (Gαq). PLC activity appeared little affected by the yeast diet; however, light-induced contractions measured by atomic force microscopy or the activation of ectopic mechanosensitive gramicidin channels were also slowed ∼2-fold. The results are consistent with mechanosensitive gating and provide a striking example of how dietary fatty acids can profoundly influence sensory performance in a classical G-protein-coupled signaling cascade.
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20
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Kapelski S, Klockenbring T, Fischer R, Barth S, Fendel R. Assessment of the neutrophilic antibody-dependent respiratory burst (ADRB) response to Plasmodium falciparum. J Leukoc Biol 2014; 96:1131-42. [PMID: 25118179 DOI: 10.1189/jlb.4a0614-283rr] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Semi-immunity against Pf malaria is based on a combination of cellular and humoral immune responses. PMNs and IgGs are considered important components of this process, but the underlying mechanisms are unclear. We investigated the neutrophilic ADRB by analyzing the production of ROS in response to Pf antigen-specific IgGs bound to solid-phase immobilized antigens (sADRB) or whole merozoites (mADRB). We found that the PMN stimulations in each assay were based on different underlying mechanisms, demonstrating the importance of the assay set-up for the evaluation of antibody-triggered PMN responses. In the sADRB assay, ROS were produced externally, and by specific blocking of CD32(a)/FcγRII(a), the immediate neutrophilic response was abolished, whereas the removal of CD16(b)/FcγRIII(b) had no substantial effect. The key role of CD32(a) was confirmed using CD16(b)-deficient PMNs, in which similar changes of neutrophilic ADRB profiles were recorded after treatment. In the mADRB assay, ROS were produced almost exclusively within the cell, suggesting that the underlying mechanism was phagocytosis. This was confirmed using an additional phagocytosis assay, in which PMNs specifically ingested merozoites opsonized with Ghanaian plasma IgGs, seven times more often than merozoites opsonized with European plasma IgGs (P<0.001). Our data show that assay set-ups used to evaluate the responses of PMNs and perhaps other effector cells must be chosen carefully to evaluate the appropriate cellular responses. Our robust, stable, and well-characterized methods could therefore be useful in malaria vaccine studies to analyze the antimalarial effector function of antibodies.
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Affiliation(s)
- Stephanie Kapelski
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Department of Pharmaceutical Product Development, Aachen, Germany; Rheinisch-Westfälische Technische Hochschule Aachen University, Institute for Molecular Biotechnology, Aachen, Germany; and
| | - Torsten Klockenbring
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Department of Pharmaceutical Product Development, Aachen, Germany
| | - Rainer Fischer
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Department of Pharmaceutical Product Development, Aachen, Germany; Rheinisch-Westfälische Technische Hochschule Aachen University, Institute for Molecular Biotechnology, Aachen, Germany; and
| | - Stefan Barth
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Department of Pharmaceutical Product Development, Aachen, Germany; Institute for Applied Medical Engineering at Rheinisch-Westfälische Technische Hochschule Aachen University and Hospital, Department of Experimental Medicine and Immunotherapy, Aachen, Germany
| | - Rolf Fendel
- Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Department of Pharmaceutical Product Development, Aachen, Germany; Rheinisch-Westfälische Technische Hochschule Aachen University, Institute for Molecular Biotechnology, Aachen, Germany; and
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21
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Zhang Y, Frohman MA. Cellular and physiological roles for phospholipase D1 in cancer. J Biol Chem 2014; 289:22567-22574. [PMID: 24990946 DOI: 10.1074/jbc.r114.576876] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Phospholipase D enzymes have long been proposed to play multiple cell biological roles in cancer. With the generation of phospholipase D1 (PLD1)-deficient mice and the development of small molecule PLD-specific inhibitors, in vivo roles for PLD1 in cancer are now being defined, both in the tumor cells and in the tumor environment. We review here tools now used to explore in vivo roles for PLD1 in cancer and summarize recent findings regarding functions in angiogenesis and metastasis.
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Affiliation(s)
- Yi Zhang
- Center for Developmental Genetics and the Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York 11794
| | - Michael A Frohman
- Center for Developmental Genetics and the Department of Pharmacological Sciences, Stony Brook University, Stony Brook, New York 11794.
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22
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Kang DW, Choi KY, Min DS. Functional regulation of phospholipase D expression in cancer and inflammation. J Biol Chem 2014; 289:22575-22582. [PMID: 24990948 DOI: 10.1074/jbc.r114.569822] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Phospholipase D (PLD) regulates downstream effectors by generating phosphatidic acid. Growing links of dysregulation of PLD to human disease have spurred interest in therapeutics that target its function. Aberrant PLD expression has been identified in multiple facets of complex pathological states, including cancer and inflammatory diseases. Thus, it is important to understand how the signaling network of PLD expression is regulated and contributes to progression of these diseases. Interestingly, small molecule PLD inhibitors can suppress PLD expression as well as enzymatic activity of PLD and have been shown to be effective in pathological mice models, suggesting the potential for use of PLD inhibitors as therapeutics against cancer and inflammation. Here, we summarize recent scientific developments regarding the regulation of PLD expression and its role in cancer and inflammatory processes.
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Affiliation(s)
- Dong Woo Kang
- Department of Molecular Biology, College of Natural Science, Pusan National University, Busan 609-735
| | - Kang-Yell Choi
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul 120-749, and; Translational Research Center for Protein Function Control, Yonsei University, Seoul 120-749, Korea
| | - Do Sik Min
- Department of Molecular Biology, College of Natural Science, Pusan National University, Busan 609-735,; Translational Research Center for Protein Function Control, Yonsei University, Seoul 120-749, Korea.
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23
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Rohwedder A, Zhang Q, Rudge SA, Wakelam MJO. Lipid droplet formation in response to oleic acid in Huh-7 cells is mediated by the fatty acid receptor FFAR4. J Cell Sci 2014; 127:3104-15. [PMID: 24876224 DOI: 10.1242/jcs.145854] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
It is unclear how changes in lipid droplet size and number are regulated - for example, it is not known whether this involves a signalling pathway or is directed by cellular lipid uptake. Here, we show that oleic acid stimulates lipid droplet formation by activating the long-chain fatty acid receptor FFAR4, which signals through a pertussis-toxin-sensitive G-protein signalling pathway involving phosphoinositide 3-kinase (PI3-kinase), AKT (also known as protein kinase B) and phospholipase D (PLD) activities. This initial lipid droplet formation is not dependent upon exogenous lipid, whereas the subsequent more sustained increase in the number of lipid droplets is dependent upon lipid uptake. These two mechanisms of lipid droplet formation point to distinct potential intervention points.
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Affiliation(s)
- Arndt Rohwedder
- Signalling Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Qifeng Zhang
- Signalling Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Simon A Rudge
- Signalling Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
| | - Michael J O Wakelam
- Signalling Programme, Babraham Institute, Babraham Research Campus, Cambridge CB22 3AT, UK
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24
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Sergeant S, McPhail LC. Measurement of phospholipid metabolism in intact neutrophils. Methods Mol Biol 2014; 1124:89-105. [PMID: 24504948 DOI: 10.1007/978-1-62703-845-4_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Phospholipid-metabolizing enzymes are important participants in neutrophil signal transduction pathways. The methods discussed herein describe assays for assessing the activities of phospholipase A2 (PLA2), phospholipase C (PLC), phospholipase D (PLD), and phosphoinositide 3-OH-kinase in intact neutrophils. PLA2 activity is measured as the release of radiolabeled arachidonic acid. PLC activity is measured as the accumulation of inositol 1,4,5-trisphosphate (IP3), a water-soluble product, using a commercially available radioreceptor assay kit. PLD activity is measured as the appearance of its radiolabeled products, phosphatidic acid and phosphatidylethanol. PI3-K activity is measured as the appearance of its radiolabeled product, phosphatidylinositol-3,4,5-trisphosphate.
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Affiliation(s)
- Susan Sergeant
- Department of Biochemistry, Wake Forest University School of Medicine, Winston-Salem, NC, USA
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25
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Dibble CC, Manning BD. Signal integration by mTORC1 coordinates nutrient input with biosynthetic output. Nat Cell Biol 2013; 15:555-64. [PMID: 23728461 DOI: 10.1038/ncb2763] [Citation(s) in RCA: 535] [Impact Index Per Article: 48.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Flux through metabolic pathways is inherently sensitive to the levels of specific substrates and products, but cellular metabolism is also managed by integrated control mechanisms that sense the nutrient and energy status of a cell or organism. The mechanistic target of rapamycin complex 1 (mTORC1), a protein kinase complex ubiquitous to eukaryotic cells, has emerged as a critical signalling node that links nutrient sensing to the coordinated regulation of cellular metabolism. Here, we discuss the role of mTORC1 as a conduit between cellular growth conditions and the anabolic processes that promote cell growth. The emerging network of signalling pathways through which mTORC1 integrates systemic signals (secreted growth factors) with local signals (cellular nutrients - amino acids, glucose and oxygen - and energy, ATP) is detailed. Our expanding understanding of the regulatory network upstream of mTORC1 provides molecular insights into the integrated sensing mechanisms by which diverse cellular signals converge to control cell physiology.
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Affiliation(s)
- Christian C Dibble
- Division of Signal Transduction, Beth Israel Deaconess Medical Center, Systems Biology Department, Harvard Medical School, Boston, Massachusetts 02115, USA
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26
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Jaafar R, De Larichaudy J, Chanon S, Euthine V, Durand C, Naro F, Bertolino P, Vidal H, Lefai E, Némoz G. Phospholipase D regulates the size of skeletal muscle cells through the activation of mTOR signaling. Cell Commun Signal 2013; 11:55. [PMID: 23915343 PMCID: PMC3765503 DOI: 10.1186/1478-811x-11-55] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2012] [Accepted: 07/18/2013] [Indexed: 12/13/2022] Open
Abstract
mTOR is a major actor of skeletal muscle mass regulation in situations of atrophy or hypertrophy. It is established that Phospholipase D (PLD) activates mTOR signaling, through the binding of its product phosphatidic acid (PA) to mTOR protein. An influence of PLD on muscle cell size could thus be suspected. We explored the consequences of altered expression and activity of PLD isoforms in differentiated L6 myotubes. Inhibition or down-regulation of the PLD1 isoform markedly decreased myotube size and muscle specific protein content. Conversely, PLD1 overexpression induced muscle cell hypertrophy, both in vitro in myotubes and in vivo in mouse gastrocnemius. In the presence of atrophy-promoting dexamethasone, PLD1 overexpression or addition of exogenous PA protected myotubes against atrophy. Similarly, exogenous PA protected myotubes against TNFα-induced atrophy. Moreover, the modulation of PLD expression or activity in myotubes showed that PLD1 negatively regulates the expression of factors involved in muscle protein degradation, such as the E3-ubiquitin ligases Murf1 and Atrogin-1, and the Foxo3 transcription factor. Inhibition of mTOR by PP242 abolished the positive effects of PLD1 on myotubes, whereas modulating PLD influenced the phosphorylation of both S6K1 and Akt, which are respectively substrates of mTORC1 and mTORC2 complexes. These observations suggest that PLD1 acts through the activation of both mTORC1 and mTORC2 to induce positive trophic effects on muscle cells. This pathway may offer interesting therapeutic potentialities in the treatment of muscle wasting.
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Affiliation(s)
- Rami Jaafar
- Lyon 1 University, INSERM U1060, CarMeN Laboratory, Institut National de la Recherche Agronomique USC1235, F-69600 Oullins, France
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27
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Tsai YR, Huang LJ, Lin HY, Hung YJ, Lee MR, Kuo SC, Hsu MF, Wang JP. Inhibition of formyl peptide-stimulated phospholipase D activation by Fal-002-2 via blockade of the Arf6, RhoA and protein kinase C signaling pathways in rat neutrophils. Naunyn Schmiedebergs Arch Pharmacol 2013; 386:507-19. [PMID: 23525454 DOI: 10.1007/s00210-013-0851-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2012] [Accepted: 03/11/2013] [Indexed: 01/09/2023]
Abstract
Three recently developed selective phospholipase D (PLD) inhibitors N-(2-(4-(2-oxo-2,3-dihydro-1H-benzo[d]imidazol-1-yl)piperidin-1-yl)ethyl)-2-naphthamide (VU0155056), (S)-N-(1-(4-(5-chloro-2-oxo-2,3-dihydro-1H-benzo[d]imidazol-1-yl)piperidin-1-yl)propan-2-yl)-2-naphthamide (VU0155069), and N-(2-(4-oxo-1-phenyl-1,3,8-triazaspiro[4,5]decan-8-yl)ethyl)quinoline-3-carboxamide (VU0285655-1) inhibited O2 (•-) generation in formyl-Met-Leu-Phe (fMLP)-stimulated rat neutrophils. A novel 2-phenyl-4-quinolone compound 6-chloro-2-(2-chlorophenyl)-4-oxo-1,4-dihydroquinoline-3-carboxylate (Fal-002-2), which inhibited O2 (•-) generation, also reduced the fMLP- but not phorbol ester-stimulated PLD activity (IC50 16.0 ± 5.0 μM). Fal-002-2 attenuated the interaction of PLD1 with ADP-ribosylation factor (Arf) 6, Ras homology (Rho) A and protein kinase C (PKC) isoforms (α, βI, and βII), and also inhibited the membrane recruitment of Arf6 and RhoA in fMLP-stimulated neutrophils, but not in GTPγS-stimulated cell-free system. The cellular levels of GTP-bound Arf6 and GTP-bound RhoA were reduced by Fal-002-2. Fal-002-2 also attenuated the membrane recruitment of Rho-associated protein kinase 1, phosphorylation of myosin light chain 2 at Thr18/Ser19 and PLD1 at Thr147, and the interaction of Arf6 with both arfaptin 1 and phosphatidylinositol 4-phosphate 5-kinase 1A. The association between RhoA and Vav, the interaction of Vav with both Lyn and Lck, the membrane recruitment of Vav, and the phosphorylation of Vav at Tyr174, but not Src family at Tyr416, were all attenuated by Fal-002-2 in fMLP-stimulated neutrophils. These results indicate that Fal-002-2 is not a direct PLD inhibitor, but the inhibition of fMLP-stimulated PLD activity by Fal-002-2, which partly accounts for its suppression of O2 (•-) generation, is attributable to the blockade of both Arf6 and RhoA activation and attenuation of the interaction of Arf6, RhoA and PKC isoforms with PLD1 in rat neutrophils.
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Affiliation(s)
- Ya-Ru Tsai
- Department of Medical Research, Taichung Veterans General Hospital, 160, Section 3, Chung Kang Road, Taichung, 407, Taiwan
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Mahankali M, Henkels KM, Gomez-Cambronero J. A GEF-to-phospholipase molecular switch caused by phosphatidic acid, Rac and JAK tyrosine kinase that explains leukocyte cell migration. J Cell Sci 2013; 126:1416-28. [PMID: 23378025 PMCID: PMC3644142 DOI: 10.1242/jcs.117960] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/19/2012] [Indexed: 12/22/2022] Open
Abstract
Phospholipase D2 (PLD2) is a cell-signaling molecule that bears two activities: a guanine-nucleotide exchange factor (GEF) and a lipase that reside in the PX/PH domains and in two HKD domains, respectively. Upon cell stimulation, the GEF activity yields Rac2-GTP and the lipase activity yields phosphatidic acid (PA). In the present study, we show for the first time that these activities regulate one another. Upon cell stimulation, both GEF and lipase activities are quickly (within ∼3 min) elevated. As soon as it is produced, PA positively feeds back on the GEF and further activates it. Rac2-GTP, on the other hand, is inhibitory to the lipase activity. PLD2 would remain downregulated if it were not for the contribution of the tyrosine kinase Janus kinase 3 (JAK3), which restores lipase action (by phosphorylation at Y415). Conversely, the GEF is inhibited upon phosphorylation by JAK3 and is effectively terminated by this action and by the increasing accumulation of PA at >15 min of cell stimulation. This PA interferes with the ability of the GEF to bind to its substrate (Rac2-GTP). Thus, both temporal inter-regulation and phosphorylation-dependent mechanisms are involved in determining a GEF-lipase switch within the same molecule. Human neutrophils stimulated by interleukin-8 follow a biphasic pattern of GEF and lipase activation that can be explained by such an intramolecular switch. This is the first report of a temporal inter-regulation of two enzymatic activities that reside in the same molecule with profound biological consequences in leukocyte cell migration.
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Affiliation(s)
| | | | - Julian Gomez-Cambronero
- Department of Biochemistry and Molecular Biology, Wright State University School of Medicine, OH 45435, USA
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Phospholipases of mineralization competent cells and matrix vesicles: roles in physiological and pathological mineralizations. Int J Mol Sci 2013; 14:5036-129. [PMID: 23455471 PMCID: PMC3634480 DOI: 10.3390/ijms14035036] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 01/24/2013] [Accepted: 01/25/2013] [Indexed: 02/08/2023] Open
Abstract
The present review aims to systematically and critically analyze the current knowledge on phospholipases and their role in physiological and pathological mineralization undertaken by mineralization competent cells. Cellular lipid metabolism plays an important role in biological mineralization. The physiological mechanisms of mineralization are likely to take place in tissues other than in bones and teeth under specific pathological conditions. For instance, vascular calcification in arteries of patients with renal failure, diabetes mellitus or atherosclerosis recapitulates the mechanisms of bone formation. Osteoporosis—a bone resorbing disease—and rheumatoid arthritis originating from the inflammation in the synovium are also affected by cellular lipid metabolism. The focus is on the lipid metabolism due to the effects of dietary lipids on bone health. These and other phenomena indicate that phospholipases may participate in bone remodelling as evidenced by their expression in smooth muscle cells, in bone forming osteoblasts, chondrocytes and in bone resorbing osteoclasts. Among various enzymes involved, phospholipases A1 or A2, phospholipase C, phospholipase D, autotaxin and sphingomyelinase are engaged in membrane lipid remodelling during early stages of mineralization and cell maturation in mineralization-competent cells. Numerous experimental evidences suggested that phospholipases exert their action at various stages of mineralization by affecting intracellular signaling and cell differentiation. The lipid metabolites—such as arachidonic acid, lysophospholipids, and sphingosine-1-phosphate are involved in cell signaling and inflammation reactions. Phospholipases are also important members of the cellular machinery engaged in matrix vesicle (MV) biogenesis and exocytosis. They may favour mineral formation inside MVs, may catalyse MV membrane breakdown necessary for the release of mineral deposits into extracellular matrix (ECM), or participate in hydrolysis of ECM. The biological functions of phospholipases are discussed from the perspective of animal and cellular knockout models, as well as disease implications, development of potent inhibitors and therapeutic interventions.
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Bohdanowicz M, Grinstein S. Role of Phospholipids in Endocytosis, Phagocytosis, and Macropinocytosis. Physiol Rev 2013; 93:69-106. [DOI: 10.1152/physrev.00002.2012] [Citation(s) in RCA: 198] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Endocytosis, phagocytosis, and macropinocytosis are fundamental processes that enable cells to sample their environment, eliminate pathogens and apoptotic bodies, and regulate the expression of surface components. While a great deal of effort has been devoted over many years to understanding the proteins involved in these processes, the important contribution of phospholipids has only recently been appreciated. This review is an attempt to collate and analyze the rapidly emerging evidence documenting the role of phospholipids in clathrin-mediated endocytosis, phagocytosis, and macropinocytosis. A primer on phospholipid biosynthesis, catabolism, subcellular distribution, and transport is presented initially, for reference, together with general considerations of the effects of phospholipids on membrane curvature and charge. This is followed by a detailed analysis of the critical functions of phospholipids in the internalization processes and in the maturation of the resulting vesicles and vacuoles as they progress along the endo-lysosomal pathway.
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Affiliation(s)
- Michal Bohdanowicz
- Division of Cell Biology, Hospital for Sick Children, and Institute of Medical Sciences, University of Toronto, Toronto, Canada
| | - Sergio Grinstein
- Division of Cell Biology, Hospital for Sick Children, and Institute of Medical Sciences, University of Toronto, Toronto, Canada
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Molecular mechanisms of N-formyl-methionyl-leucyl-phenylalanine-induced superoxide generation and degranulation in mouse neutrophils: phospholipase D is dispensable. Mol Cell Biol 2012; 33:136-45. [PMID: 23109426 DOI: 10.1128/mcb.00869-12] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Phospholipase D (PLD), which produces the lipid messenger phosphatidic acid (PA), has been implicated in superoxide generation and degranulation in neutrophils. The basis for this conclusion is the observation that primary alcohols, which interfere with PLD-catalyzed PA production, inhibit these neutrophil functions. However, off-target effects of primary alcohols cannot be totally excluded. Here, we generated PLD(-/-) mice in order to reevaluate the involvement of PLD in and investigate the molecular mechanisms of these neutrophil functions. Surprisingly, N-formyl-methionyl-leucyl-phenylalanine (fMLP) induced these functions in PLD(-/-) neutrophils, and these functions were suppressed by ethanol. These results indicate that PLD is dispensable for these neutrophil functions and that ethanol nonspecifically inhibits them, warning against the use of primary alcohols as specific inhibitors of PLD-mediated PA formation. The calcium ionophore ionomycin and the membrane-permeative compound 1-oleoyl-2-acetyl-sn-glycerol (OADG) synergistically induced superoxide generation. On the other hand, ionomycin alone induced degranulation, which was further augmented by OADG. These results demonstrate that conventional protein kinase C (cPKC) is crucial for superoxide generation, and a Ca(2+)-dependent signaling pathway(s) and cPKC are involved in degranulation in mouse neutrophils.
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GPCR activation of Ras and PI3Kc in neutrophils depends on PLCb2/b3 and the RasGEF RasGRP4. EMBO J 2012; 31:3118-29. [PMID: 22728827 PMCID: PMC3400018 DOI: 10.1038/emboj.2012.167] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Accepted: 05/15/2012] [Indexed: 12/31/2022] Open
Abstract
The molecular mechanisms by which receptors regulate the Ras Binding Domains of the PIP3-generating, class I PI3Ks remain poorly understood, despite their importance in a range of biological settings, including tumorigenesis, activation of neutrophils by pro-inflammatory mediators, chemotaxis of Dictyostelium and cell growth in Drosophila. We provide evidence that G protein-coupled receptors (GPCRs) can stimulate PLCb2/b3 and diacylglycerol- dependent activation of the RasGEF, RasGRP4 in neutrophils. The genetic loss of RasGRP4 phenocopies knock-in of a Ras-insensitive version of PI3Kc in its effects on PI3Kc-dependent PIP3 accumulation, PKB activation, chemokinesis and reactive oxygen species (ROS) formation. These results establish a new mechanism by which GPCRs can stimulate Ras, and the broadly important principle that PLCs can control activation of class I PI3Ks.
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Selvy PE, Lavieri RR, Lindsley CW, Brown HA. Phospholipase D: enzymology, functionality, and chemical modulation. Chem Rev 2011; 111:6064-119. [PMID: 21936578 PMCID: PMC3233269 DOI: 10.1021/cr200296t] [Citation(s) in RCA: 251] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Paige E Selvy
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee 37064, USA
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