1
|
Gore E, Duparc T, Genoux A, Perret B, Najib S, Martinez LO. The Multifaceted ATPase Inhibitory Factor 1 (IF1) in Energy Metabolism Reprogramming and Mitochondrial Dysfunction: A New Player in Age-Associated Disorders? Antioxid Redox Signal 2022; 37:370-393. [PMID: 34605675 PMCID: PMC9398489 DOI: 10.1089/ars.2021.0137] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Significance: The mitochondrial oxidative phosphorylation (OXPHOS) system, comprising the electron transport chain and ATP synthase, generates membrane potential, drives ATP synthesis, governs energy metabolism, and maintains redox balance. OXPHOS dysfunction is associated with a plethora of diseases ranging from rare inherited disorders to common conditions, including diabetes, cancer, neurodegenerative diseases, as well as aging. There has been great interest in studying regulators of OXPHOS. Among these, ATPase inhibitory factor 1 (IF1) is an endogenous inhibitor of ATP synthase that has long been thought to avoid the consumption of cellular ATP when ATP synthase acts as an ATP hydrolysis enzyme. Recent Advances: Recent data indicate that IF1 inhibits ATP synthesis and is involved in a multitude of mitochondrial-related functions, such as mitochondrial quality control, energy metabolism, redox balance, and cell fate. IF1 also inhibits the ATPase activity of cell-surface ATP synthase, and it is used as a cardiovascular disease biomarker. Critical Issues: Although recent data have led to a paradigm shift regarding IF1 functions, these have been poorly studied in entire organisms and in different organs. The understanding of the cellular biology of IF1 is, therefore, still limited. The aim of this review was to provide an overview of the current understanding of the role of IF1 in mitochondrial functions, health, and diseases. Future Directions: Further investigations of IF1 functions at the cell, organ, and whole-organism levels and in different pathophysiological conditions will help decipher the controversies surrounding its involvement in mitochondrial function and could unveil therapeutic strategies in human pathology. Antioxid. Redox Signal. 37, 370-393.
Collapse
Affiliation(s)
- Emilia Gore
- I2MC, University of Toulouse, INSERM, UPS, Toulouse, France
| | - Thibaut Duparc
- I2MC, University of Toulouse, INSERM, UPS, Toulouse, France
| | - Annelise Genoux
- I2MC, University of Toulouse, INSERM, UPS, Toulouse, France.,Service de Biochimie, Pôle de biologie, Hôpital de Purpan, CHU de Toulouse, Toulouse, France
| | - Bertrand Perret
- I2MC, University of Toulouse, INSERM, UPS, Toulouse, France.,Service de Biochimie, Pôle de biologie, Hôpital de Purpan, CHU de Toulouse, Toulouse, France
| | - Souad Najib
- I2MC, University of Toulouse, INSERM, UPS, Toulouse, France
| | | |
Collapse
|
2
|
Mishra K, Péter M, Nardiello AM, Keller G, Llado V, Fernandez-Garcia P, Kahlert UD, Barasch D, Saada A, Török Z, Balogh G, Escriba PV, Piotto S, Kakhlon O. Multifaceted Analyses of Isolated Mitochondria Establish the Anticancer Drug 2-Hydroxyoleic Acid as an Inhibitor of Substrate Oxidation and an Activator of Complex IV-Dependent State 3 Respiration. Cells 2022; 11:cells11030578. [PMID: 35159387 PMCID: PMC8834245 DOI: 10.3390/cells11030578] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 02/01/2022] [Accepted: 02/05/2022] [Indexed: 02/04/2023] Open
Abstract
The synthetic fatty acid 2-hydroxyoleic acid (2OHOA) has been extensively investigated as a cancer therapy mainly based on its regulation of membrane lipid composition and structure, activating various cell fate pathways. We discovered, additionally, that 2OHOA can uncouple oxidative phosphorylation, but this has never been demonstrated mechanistically. Here, we explored the effect of 2OHOA on mitochondria isolated by ultracentrifugation from U118MG glioblastoma cells. Mitochondria were analyzed by shotgun lipidomics, molecular dynamic simulations, spectrophotometric assays for determining respiratory complex activity, mass spectrometry for assessing beta oxidation and Seahorse technology for bioenergetic profiling. We showed that the main impact of 2OHOA on mitochondrial lipids is their hydroxylation, demonstrated by simulations to decrease co-enzyme Q diffusion in the liquid disordered membranes embedding respiratory complexes. This decreased co-enzyme Q diffusion can explain the inhibition of disjointly measured complexes I–III activity. However, it doesn’t explain how 2OHOA increases complex IV and state 3 respiration in intact mitochondria. This increased respiration probably allows mitochondrial oxidative phosphorylation to maintain ATP production against the 2OHOA-mediated inhibition of glycolytic ATP production. This work correlates 2OHOA function with its modulation of mitochondrial lipid composition, reflecting both 2OHOA anticancer activity and adaptation to it by enhancement of state 3 respiration.
Collapse
Affiliation(s)
- Kumudesh Mishra
- Department of Neurology, Hadassah-Hebrew University Medical Center, Ein Kerem, Jerusalem 9112102, Israel;
- Faculty of Medicine, Hebrew University of Jerusalem, Ein Kerem, Jerusalem 9112102, Israel; (G.K.); (D.B.); (A.S.)
| | - Mária Péter
- Lipodom Ltd., Dorottya Utca 35-37, 6726 Szeged, Hungary; (M.P.); (Z.T.); (G.B.)
- Biological Research Centre, Institute of Biochemistry, 6726 Szeged, Hungary
| | - Anna Maria Nardiello
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, SA, Italy;
- Bionam Center for Biomaterials, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, SA, Italy
| | - Guy Keller
- Faculty of Medicine, Hebrew University of Jerusalem, Ein Kerem, Jerusalem 9112102, Israel; (G.K.); (D.B.); (A.S.)
- Department of Genetics, Hadassah-Hebrew University Medical Center, Ein Kerem, Jerusalem 9112102, Israel
| | - Victoria Llado
- Laminar Pharmaceuticals, Ctra. de Valldemossa Km. 7, 4 Parc BIT Ed. Naorte Bolque A-1°-3, 07121 Palma de Mallorca, Spain; (V.L.); (P.F.-G.)
| | - Paula Fernandez-Garcia
- Laminar Pharmaceuticals, Ctra. de Valldemossa Km. 7, 4 Parc BIT Ed. Naorte Bolque A-1°-3, 07121 Palma de Mallorca, Spain; (V.L.); (P.F.-G.)
| | - Ulf D. Kahlert
- Molecular and Experimental Surgery, Clinic for General, Visceral, Vascular, and Transplant Surgery, Medical Faculty, University Hospital Magdeburg, 39120 Magdeburg, Germany;
| | - Dinorah Barasch
- Faculty of Medicine, Hebrew University of Jerusalem, Ein Kerem, Jerusalem 9112102, Israel; (G.K.); (D.B.); (A.S.)
- Mass Spectrometry Unit, Institute for Drug Research, School of Pharmacy, The Hebrew University of Jerusalem, Jerusalem 9112102, Israel
| | - Ann Saada
- Faculty of Medicine, Hebrew University of Jerusalem, Ein Kerem, Jerusalem 9112102, Israel; (G.K.); (D.B.); (A.S.)
- Department of Genetics, Hadassah-Hebrew University Medical Center, Ein Kerem, Jerusalem 9112102, Israel
| | - Zsolt Török
- Lipodom Ltd., Dorottya Utca 35-37, 6726 Szeged, Hungary; (M.P.); (Z.T.); (G.B.)
- Biological Research Centre, Institute of Biochemistry, 6726 Szeged, Hungary
| | - Gábor Balogh
- Lipodom Ltd., Dorottya Utca 35-37, 6726 Szeged, Hungary; (M.P.); (Z.T.); (G.B.)
- Biological Research Centre, Institute of Biochemistry, 6726 Szeged, Hungary
| | - Pablo V. Escriba
- Laminar Pharmaceuticals, Ctra. de Valldemossa Km. 7, 4 Parc BIT Ed. Naorte Bolque A-1°-3, 07121 Palma de Mallorca, Spain; (V.L.); (P.F.-G.)
- Department of Biology, University of the Balearic Islands, 07122 Palma de Mallorca, Spain
- Correspondence: (P.V.E.); (S.P.); (O.K.)
| | - Stefano Piotto
- Department of Pharmacy, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, SA, Italy;
- Bionam Center for Biomaterials, University of Salerno, Via Giovanni Paolo II, 132, 84084 Fisciano, SA, Italy
- Correspondence: (P.V.E.); (S.P.); (O.K.)
| | - Or Kakhlon
- Department of Neurology, Hadassah-Hebrew University Medical Center, Ein Kerem, Jerusalem 9112102, Israel;
- Faculty of Medicine, Hebrew University of Jerusalem, Ein Kerem, Jerusalem 9112102, Israel; (G.K.); (D.B.); (A.S.)
- Correspondence: (P.V.E.); (S.P.); (O.K.)
| |
Collapse
|
3
|
Dabbaghizadeh A, Tanguay RM. Structural and functional properties of proteins interacting with small heat shock proteins. Cell Stress Chaperones 2020; 25:629-637. [PMID: 32314314 PMCID: PMC7332586 DOI: 10.1007/s12192-020-01097-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/12/2020] [Indexed: 12/13/2022] Open
Abstract
Small heat shock proteins (sHsps) are ubiquitous molecular chaperones found in all domains of life, possessing significant roles in protein quality control in cells and assisting the refolding of non-native proteins. They are efficient chaperones against many in vitro protein substrates. Nevertheless, the in vivo native substrates of sHsps are not known. To better understand the functions of sHsps and the mechanisms by which they enhance heat resistance, sHsp-interacting proteins were identified using affinity purification under heat shock conditions. This paper aims at providing some insights into the characteristics of natural substrate proteins of sHsps. It seems that sHsps of prokaryotes, as well as sHsps of some eukaryotes, can bind to a wide range of substrate proteins with a preference for certain functional classes of proteins. Using Drosophila melanogaster mitochondrial Hsp22 as a model system, we observed that this sHsp interacted with the members of ATP synthase machinery. Mechanistically, Hsp22 interacts with the multi-type substrate proteins under heat shock conditions as well as non-heat shock conditions.
Collapse
Affiliation(s)
- Afrooz Dabbaghizadeh
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Québec, Canada
| | - Robert M Tanguay
- Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, Québec, Canada.
| |
Collapse
|
4
|
Dabbaghizadeh A, Morrow G, Amer YO, Chatelain EH, Pichaud N, Tanguay RM. Identification of proteins interacting with the mitochondrial small heat shock protein Hsp22 of Drosophila melanogaster: Implication in mitochondrial homeostasis. PLoS One 2018; 13:e0193771. [PMID: 29509794 PMCID: PMC5839585 DOI: 10.1371/journal.pone.0193771] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Accepted: 02/16/2018] [Indexed: 12/17/2022] Open
Abstract
The small heat shock protein (sHsp) Hsp22 from Drosophila melanogaster (DmHsp22) is part of the family of sHsps in this diptera. This sHsp is characterized by its presence in the mitochondrial matrix as well as by its preferential expression during ageing. Although DmHsp22 has been demonstrated to be an efficient in vitro chaperone, its function within mitochondria in vivo remains largely unknown. Thus, determining its protein-interaction network (interactome) in the mitochondrial matrix would help to shed light on its function(s). In the present study we combined immunoaffinity conjugation (IAC) with mass spectroscopy analysis of mitochondria from HeLa cells transfected with DmHsp22 in non-heat shock condition and after heat shock (HS). 60 common DmHsp22-binding mitochondrial partners were detected in two independent IACs. Immunoblotting was used to validate interaction between DmHsp22 and two members of the mitochondrial chaperone machinery; Hsp60 and Hsp70. Among the partners of DmHsp22, several ATP synthase subunits were found. Moreover, we showed that expression of DmHsp22 in transiently transfected HeLa cells increased maximal mitochondrial oxygen consumption capacity and ATP contents, providing a mechanistic link between DmHsp22 and mitochondrial functions.
Collapse
Affiliation(s)
- Afrooz Dabbaghizadeh
- Laboratoire de Génétique Cellulaire et Développementale, IBIS and PROTEO, Département de Biologie Moléculaire, Biochimie Médicale et Pathologie, Faculté de Médecine, Université Laval, Québec, Canada
| | - Geneviève Morrow
- Laboratoire de Génétique Cellulaire et Développementale, IBIS and PROTEO, Département de Biologie Moléculaire, Biochimie Médicale et Pathologie, Faculté de Médecine, Université Laval, Québec, Canada
| | - Yasmine Ould Amer
- Laboratoire de Signalisation Mitochondriale, Département de Biologie, Université de Moncton, Moncton, NB, Canada
| | - Etienne Hebert Chatelain
- Laboratoire de Signalisation Mitochondriale, Département de Biologie, Université de Moncton, Moncton, NB, Canada
| | - Nicolas Pichaud
- Laboratoire de Biochimie et Physiologie Comparée, Département de Chimie et Biochimie, Université de Moncton, Moncton, NB, Canada
| | - Robert M Tanguay
- Laboratoire de Génétique Cellulaire et Développementale, IBIS and PROTEO, Département de Biologie Moléculaire, Biochimie Médicale et Pathologie, Faculté de Médecine, Université Laval, Québec, Canada
| |
Collapse
|
5
|
Taurino F, Gnoni A. Systematic review of plasma-membrane ecto-ATP synthase: A new player in health and disease. Exp Mol Pathol 2018; 104:59-70. [DOI: 10.1016/j.yexmp.2017.12.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 12/15/2017] [Accepted: 12/31/2017] [Indexed: 02/07/2023]
|
6
|
Morel E, Ghezzal S, Lucchi G, Truntzer C, Pais de Barros JP, Simon-Plas F, Demignot S, Mineo C, Shaul PW, Leturque A, Rousset M, Carrière V. Cholesterol trafficking and raft-like membrane domain composition mediate scavenger receptor class B type 1-dependent lipid sensing in intestinal epithelial cells. Biochim Biophys Acta Mol Cell Biol Lipids 2017; 1863:199-211. [PMID: 29196159 DOI: 10.1016/j.bbalip.2017.11.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 11/13/2017] [Accepted: 11/27/2017] [Indexed: 02/02/2023]
Abstract
Scavenger receptor Class B type 1 (SR-B1) is a lipid transporter and sensor. In intestinal epithelial cells, SR-B1-dependent lipid sensing is associated with SR-B1 recruitment in raft-like/ detergent-resistant membrane domains and interaction of its C-terminal transmembrane domain with plasma membrane cholesterol. To clarify the initiating events occurring during lipid sensing by SR-B1, we analyzed cholesterol trafficking and raft-like domain composition in intestinal epithelial cells expressing wild-type SR-B1 or the mutated form SR-B1-Q445A, defective in membrane cholesterol binding and signal initiation. These features of SR-B1 were found to influence both apical cholesterol efflux and intracellular cholesterol trafficking from plasma membrane to lipid droplets, and the lipid composition of raft-like domains. Lipidomic analysis revealed likely participation of d18:0/16:0 sphingomyelin and 16:0/0:0 lysophosphatidylethanolamine in lipid sensing by SR-B1. Proteomic analysis identified proteins, whose abundance changed in raft-like domains during lipid sensing, and these included molecules linked to lipid raft dynamics and signal transduction. These findings provide new insights into the role of SR-B1 in cellular cholesterol homeostasis and suggest molecular links between SR-B1-dependent lipid sensing and cell cholesterol and lipid droplet dynamics.
Collapse
Affiliation(s)
- Etienne Morel
- Centre de Recherche des Cordeliers, INSERM, UMPC Université Paris 6, Université Paris Descartes Paris 5, CNRS, F-75006 Paris, France
| | - Sara Ghezzal
- Centre de Recherche des Cordeliers, INSERM, UMPC Université Paris 6, Université Paris Descartes Paris 5, CNRS, F-75006 Paris, France
| | - Géraldine Lucchi
- Clinical Innovation Proteomic Platform CLIPP, Université Bourgogne Franche-Comté, F-21000 Dijon, France
| | - Caroline Truntzer
- Clinical Innovation Proteomic Platform CLIPP, Université Bourgogne Franche-Comté, F-21000 Dijon, France
| | - Jean-Paul Pais de Barros
- Plateforme de Lipidomique, INSERM UMR1231, Université de Bourgogne Franche Comté, F-21000 Dijon, France
| | - Françoise Simon-Plas
- Agroécologie, AgroSup Dijon, CNRS, INRA, Université Bourgogne Franche-Comté, F-21000 Dijon, France
| | - Sylvie Demignot
- Centre de Recherche des Cordeliers, INSERM, UMPC Université Paris 6, Université Paris Descartes Paris 5, CNRS, F-75006 Paris, France; EPHE, PSL Research University, F-75006 Paris, France
| | - Chieko Mineo
- Center for Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas, Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Philip W Shaul
- Center for Pulmonary and Vascular Biology, Department of Pediatrics, University of Texas, Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Armelle Leturque
- Centre de Recherche des Cordeliers, INSERM, UMPC Université Paris 6, Université Paris Descartes Paris 5, CNRS, F-75006 Paris, France
| | - Monique Rousset
- Centre de Recherche des Cordeliers, INSERM, UMPC Université Paris 6, Université Paris Descartes Paris 5, CNRS, F-75006 Paris, France
| | - Véronique Carrière
- Centre de Recherche des Cordeliers, INSERM, UMPC Université Paris 6, Université Paris Descartes Paris 5, CNRS, F-75006 Paris, France.
| |
Collapse
|
7
|
GRP78 Is an Important Host Factor for Japanese Encephalitis Virus Entry and Replication in Mammalian Cells. J Virol 2017; 91:JVI.02274-16. [PMID: 28053106 DOI: 10.1128/jvi.02274-16] [Citation(s) in RCA: 98] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 12/27/2016] [Indexed: 12/25/2022] Open
Abstract
Japanese encephalitis virus (JEV), a mosquito-borne flavivirus, is the leading cause of viral encephalitis in Southeast Asia with potential to become a global pathogen. Here, we identify glucose-regulated protein 78 (GRP78) as an important host protein for virus entry and replication. Using the plasma membrane fractions from mouse neuronal (Neuro2a) cells, mass spectroscopy analysis identified GRP78 as a protein interacting with recombinant JEV envelope protein domain III. GRP78 was found to be expressed on the plasma membranes of Neuro2a cells, mouse primary neurons, and human epithelial Huh-7 cells. Antibodies against GRP78 significantly inhibited JEV entry in all three cell types, suggesting an important role of the protein in virus entry. Depletion of GRP78 by small interfering RNA (siRNA) significantly blocked JEV entry into Neuro2a cells, further supporting its role in virus uptake. Immunofluorescence studies showed extensive colocalization of GRP78 with JEV envelope protein in virus-infected cells. This interaction was also confirmed by immunoprecipitation studies. Additionally, GRP78 was shown to have an important role in JEV replication, as treatment of cells post-virus entry with subtilase cytotoxin that specifically cleaved GRP78 led to a substantial reduction in viral RNA replication and protein synthesis, resulting in significantly reduced extracellular virus titers. Our results indicate that GRP78, an endoplasmic reticulum chaperon of the HSP70 family, is a novel host factor involved at multiple steps of the JEV life cycle and could be a potential therapeutic target.IMPORTANCE Recent years have seen a rapid spread of mosquito-borne diseases caused by flaviviruses. The flavivirus family includes West Nile, dengue, Japanese encephalitis, and Zika viruses, which are major threats to public health with potential to become global pathogens. JEV is the major cause of viral encephalitis in several parts of Southeast Asia, affecting a predominantly pediatric population with a high mortality rate. This study is focused on identification of crucial host factors that could be targeted to cripple virus infection and ultimately lead to development of effective antivirals. We have identified a cellular protein, GRP78, that plays a dual role in virus entry and virus replication, two crucial steps of the virus life cycle, and thus is a novel host factor that could be a potential therapeutic target.
Collapse
|
8
|
Lee H, Kim SH, Lee JS, Yang YH, Nam JM, Kim BW, Ko YG. Mitochondrial oxidative phosphorylation complexes exist in the sarcolemma of skeletal muscle. BMB Rep 2016; 49:116-21. [PMID: 26645635 PMCID: PMC4915115 DOI: 10.5483/bmbrep.2016.49.2.232] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Indexed: 12/22/2022] Open
Abstract
Although proteomic analyses have revealed the presence of mitochondrial oxidative
phosphorylation (OXPHOS) proteins in the plasma membrane, there have been no
in-depth evaluations of the presence or function of OXPHOS I-V in the plasma
membrane. Here, we demonstrate the in situ localization of
OXPHOS I-V complexes to the sarcolemma of skeletal muscle by immunofluorescence
and immunohistochemistry. A portion of the OXPHOS I-V complex proteins was not
co-stained with MitoTracker but co-localized with caveolin-3 in the sarcolemma
of mouse gastrocnemius. Mitochondrial matrix-facing OXPHOS complex subunits were
ectopically expressed in the sarcolemma of the non-permeabilized muscle fibers
and C2C12 myotubes. The sarcolemmal localization of cytochrome c was also
observed from mouse gastrocnemius muscles and C2C12 myotubes, as determined by
confocal and total internal resonance fluorescence (TIRF) microscopy. Based on
these data, we conclude that a portion of OXPHOS complexes is localized in the
sarcolemma of skeletal muscle and may have non-canonical functions. [BMB Reports
2016; 49(2): 116-121]
Collapse
Affiliation(s)
- Hyun Lee
- Division of Life Sciences, Korea University, Seoul 02841, Korea
| | - Seung-Hyeob Kim
- Division of Life Sciences, Korea University, Seoul 02841, Korea
| | - Jae-Seon Lee
- Department of Biomedical Sciences, College of Medicine, Inha University, Incheon 22212, Korea
| | - Yun-Hee Yang
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Jwa-Min Nam
- Department of Chemistry, Seoul National University, Seoul 08826, Korea
| | - Bong-Woo Kim
- Division of Life Sciences, Korea University, Seoul 02841, Korea
| | - Young-Gyu Ko
- Division of Life Sciences, Korea University, Seoul 02841, Korea
| |
Collapse
|
9
|
Allen-Worthington K, Xie J, Brown JL, Edmunson AM, Dowling A, Navratil AM, Scavelli K, Yoon H, Kim DG, Bynoe MS, Clarke I, Roberson MS. The F0F1 ATP Synthase Complex Localizes to Membrane Rafts in Gonadotrope Cells. Mol Endocrinol 2016; 30:996-1011. [PMID: 27482602 PMCID: PMC5414608 DOI: 10.1210/me.2015-1324] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2015] [Accepted: 07/29/2016] [Indexed: 12/22/2022] Open
Abstract
Fertility in mammals requires appropriate communication within the hypothalamic-pituitary-gonadal axis and the GnRH receptor (GnRHR) is a central conduit for this communication. The GnRHR resides in discrete membrane rafts and raft occupancy is required for signaling by GnRH. The present studies use immunoprecipitation and mass spectrometry to define peptides present within the raft associated with the GnRHR and flotillin-1, a key raft marker. These studies revealed peptides from the F0F1 ATP synthase complex. The catalytic subunits of the F1 domain were validated by immunoprecipitation, flow cytometry, and cell surface biotinylation studies demonstrating that this complex was present at the plasma membrane associated with the GnRHR. The F1 catalytic domain faces the extracellular space and catalyzes ATP synthesis when presented with ADP in normal mouse pituitary explants and a gonadotrope cell line. Steady-state extracellular ATP accumulation was blunted by coadministration of inhibitory factor 1, limiting inorganic phosphate in the media, and by chronic stimulation of the GnRHR. Steady-state extracellular ATP accumulation was enhanced by pharmacological inhibition of ecto-nucleoside triphosphate diphosphohydrolases. Kisspeptin administration induced coincident GnRH and ATP release from the median eminence into the hypophyseal-portal vasculature in ovariectomized sheep. Elevated levels of extracellular ATP augmented GnRH-induced secretion of LH from pituitary cells in primary culture, which was blocked in media containing low inorganic phosphate supporting the importance of extracellular ATP levels to gonadotrope cell function. These studies indicate that gonadotropes have intrinsic ability to metabolize ATP in the extracellular space and extracellular ATP may serve as a modulator of GnRH-induced LH secretion.
Collapse
Affiliation(s)
- Krystal Allen-Worthington
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Jianjun Xie
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Jessica L Brown
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Alexa M Edmunson
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Abigail Dowling
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Amy M Navratil
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Kurt Scavelli
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Hojean Yoon
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Do-Geun Kim
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Margaret S Bynoe
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Iain Clarke
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| | - Mark S Roberson
- Department of Biomedical Sciences (K.A.-W., J.X., J.L.B., A.M.E., A.D., K.S., H.Y., M.S.R.) and Microbiology and Immunology (D.-G.K., M.S.B.), College of Veterinary Medicine, Cornell University, Ithaca, New York 14853; Department of Zoology and Physiology (A.M.N.), College of Arts and Sciences, University of Wyoming, Laramie, Wyoming 82071; and Neuroscience Program (I.C.), Monash Biomedicine Discovery Institute and Department of Physiology, Monash University, Melbourne, Victoria 3800, Australia
| |
Collapse
|
10
|
Kim SW, Choi JH, Mukherjee R, Hwang KC, Yun JW. Proteomic identification of fat-browning markers in cultured white adipocytes treated with curcumin. Mol Cell Biochem 2016; 415:51-66. [PMID: 26915100 DOI: 10.1007/s11010-016-2676-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Accepted: 02/17/2016] [Indexed: 01/09/2023]
Abstract
We previously reported that curcumin induces browning of primary white adipocytes via enhanced expression of brown adipocyte-specific genes. In this study, we attempted to identify target proteins responsible for this fat-browning effect by analyzing proteomic changes in cultured white adipocytes in response to curcumin treatment. To elucidate the role of curcumin in fat-browning, we conducted comparative proteomic analysis of primary adipocytes between control and curcumin-treated cells using two-dimensional electrophoresis combined with MALDI-TOF-MS. We also investigated fatty acid metabolic targets, mitochondrial biogenesis, and fat-browning-associated proteins using combined proteomic and network analyses. Proteomic analysis revealed that 58 protein spots from a total of 325 matched spots showed differential expression between control and curcumin-treated adipocytes. Using network analysis, most of the identified proteins were proven to be involved in various metabolic and cellular processes based on the PANTHER classification system. One of the most striking findings is that hormone-sensitive lipase (HSL) was highly correlated with main browning markers based on the STRING database. HSL and two browning markers (UCP1, PGC-1α) were co-immunoprecipitated with these markers, suggesting that HSL possibly plays a role in fat-browning of white adipocytes. Our results suggest that curcumin increased HSL levels and other browning-specific markers, suggesting its possible role in augmentation of lipolysis and suppression of lipogenesis by trans-differentiation from white adipocytes into brown adipocytes (beige).
Collapse
Affiliation(s)
- Sang Woo Kim
- Catholic Kwandong University, International St. Mary's Hospital, Incheon Metropolitan City, 404-834, Republic of Korea. .,Institute for Bio-Medical Convergence, College of Medicine, Catholic Kwandong University, Gangneung-si, Gangwon-do, 210-701, Republic of Korea.
| | - Jae Heon Choi
- Department of Biotechnology, Daegu University, Kyungsan, Kyungbuk, 712-714, Republic of Korea
| | - Rajib Mukherjee
- Department of Biotechnology, Daegu University, Kyungsan, Kyungbuk, 712-714, Republic of Korea
| | - Ki-Chul Hwang
- Catholic Kwandong University, International St. Mary's Hospital, Incheon Metropolitan City, 404-834, Republic of Korea.,Institute for Bio-Medical Convergence, College of Medicine, Catholic Kwandong University, Gangneung-si, Gangwon-do, 210-701, Republic of Korea
| | - Jong Won Yun
- Department of Biotechnology, Daegu University, Kyungsan, Kyungbuk, 712-714, Republic of Korea.
| |
Collapse
|
11
|
Abstract
The hypothesis that the Golgi apparatus is capable of sorting proteins and sending them to the plasma membrane through "lipid rafts," membrane lipid domains highly enriched in glycosphingolipids, sphingomyelin, ceramide, and cholesterol, was formulated by van Meer and Simons in 1988 and came to a turning point when it was suggested that lipid rafts could be isolated thanks to their resistance to solubilization by some detergents, namely Triton X-100. An incredible number of papers have described the composition and properties of detergent-resistant membrane fractions. However, the use of this method has also raised the fiercest criticisms. In this chapter, we would like to discuss the most relevant methodological aspects related to the preparation of detergent-resistant membrane fractions, and to discuss the importance of discriminating between what is present on a cell membrane and what we can prepare from cell membranes in a laboratory tube.
Collapse
|
12
|
Chowdhury SM, Zhu X, Aloor JJ, Azzam KM, Gabor KA, Ge W, Addo KA, Tomer KB, Parks JS, Fessler MB. Proteomic Analysis of ABCA1-Null Macrophages Reveals a Role for Stomatin-Like Protein-2 in Raft Composition and Toll-Like Receptor Signaling. Mol Cell Proteomics 2015; 14:1859-70. [PMID: 25910759 DOI: 10.1074/mcp.m114.045179] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2014] [Indexed: 11/06/2022] Open
Abstract
Lipid raft membrane microdomains organize signaling by many prototypical receptors, including the Toll-like receptors (TLRs) of the innate immune system. Raft-localization of proteins is widely thought to be regulated by raft cholesterol levels, but this is largely on the basis of studies that have manipulated cell cholesterol using crude and poorly specific chemical tools, such as β-cyclodextrins. To date, there has been no proteome-scale investigation of whether endogenous regulators of intracellular cholesterol trafficking, such as the ATP binding cassette (ABC)A1 lipid efflux transporter, regulate targeting of proteins to rafts. Abca1(-/-) macrophages have cholesterol-laden rafts that have been reported to contain increased levels of select proteins, including TLR4, the lipopolysaccharide receptor. Here, using quantitative proteomic profiling, we identified 383 proteins in raft isolates from Abca1(+/+) and Abca1(-/-) macrophages. ABCA1 deletion induced wide-ranging changes to the raft proteome. Remarkably, many of these changes were similar to those seen in Abca1(+/+) macrophages after lipopolysaccharide exposure. Stomatin-like protein (SLP)-2, a member of the stomatin-prohibitin-flotillin-HflK/C family of membrane scaffolding proteins, was robustly and specifically increased in Abca1(-/-) rafts. Pursuing SLP-2 function, we found that rafts of SLP-2-silenced macrophages had markedly abnormal composition. SLP-2 silencing did not compromise ABCA1-dependent cholesterol efflux but reduced macrophage responsiveness to multiple TLR ligands. This was associated with reduced raft levels of the TLR co-receptor, CD14, and defective lipopolysaccharide-induced recruitment of the common TLR adaptor, MyD88, to rafts. Taken together, we show that the lipid transporter ABCA1 regulates the protein repertoire of rafts and identify SLP-2 as an ABCA1-dependent regulator of raft composition and of the innate immune response.
Collapse
Affiliation(s)
| | - Xuewei Zhu
- ¶Section on Molecular Medicine, Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27157
| | - Jim J Aloor
- From the ‡Laboratory of Respiratory Biology and
| | | | | | - William Ge
- From the ‡Laboratory of Respiratory Biology and
| | | | - Kenneth B Tomer
- §Laboratory of Structural Biology, National Institute of Environmental Health Sciences, NIH, Research Triangle Park, NC 27709
| | - John S Parks
- ¶Section on Molecular Medicine, Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, NC 27157
| | | |
Collapse
|
13
|
Peng WH, Lee YC, Chau YP, Lu KS, Kung HN. Short-term exposure of zebrafish embryos to arecoline leads to retarded growth, motor impairment, and somite muscle fiber changes. Zebrafish 2014; 12:58-70. [PMID: 25549301 DOI: 10.1089/zeb.2014.1010] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The areca nut-chewing habit is common in Southeast Asia, India, and Taiwan, and arecoline is the most abundant and potent component in the areca nut. The effects of arecoline on birth defects have been explored in many species, including chicken, mice, and zebrafish. The effects of arecoline on embryos after long-term exposure are well established; however, the effects of short-term embryo exposure to arecoline are not understood. Using zebrafish, we study the effects of short-term exposure of arecoline on embryos to model the human habit of areca nut-chewing during early pregnancy. Arecoline, at concentrations from 0.001% to 0.04%, was administered to zebrafish embryos from 4 to 24 hours post fertilization. The morphological changes, survival rates, body length, and skeletal muscle fiber structure were then investigated by immunohistochemistry, confocal microscopy, and conventional electron microscopy. With exposure of embryos to increasing arecoline concentrations, we observed a significant decline in the hatching and survival rates, general growth retardation, lower locomotor activity, and swimming ability impairment. Immunofluorescent staining demonstrated a loose arrangement of myosin heavy chains, and ultrastructural observations revealed altered myofibril arrangement and swelling of the mitochondria. In addition, the results of flow-cytometry and JC-1 staining to assay mitochondria activity, as well as reverse transcription-polymerase chain reaction analyses of functional gene expression, revealed mitochondrial dysfunctions after exposure to arecoline. We confirmed that short-term arecoline exposure resulted in retarded embryonic development and decreased locomotor activity due to defective somitic skeletal muscle development and mitochondrial dysfunction.
Collapse
Affiliation(s)
- Wei-Hau Peng
- 1 Department of Anatomy and Cell Biology, College of Medicine, National Taiwan University , Taipei, Taiwan
| | | | | | | | | |
Collapse
|
14
|
Thomas PV, Cheng AL, Colby CC, Liu L, Patel CK, Josephs L, Duncan RK. Localization and proteomic characterization of cholesterol-rich membrane microdomains in the inner ear. J Proteomics 2014; 103:178-93. [PMID: 24713161 DOI: 10.1016/j.jprot.2014.03.037] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 03/25/2014] [Accepted: 03/26/2014] [Indexed: 12/14/2022]
Abstract
UNLABELLED Biological membranes organize and compartmentalize cell signaling into discrete microdomains, a process that often involves stable, cholesterol-rich platforms that facilitate protein-protein interactions. Polarized cells with distinct apical and basolateral cell processes rely on such compartmentalization to maintain proper function. In the cochlea, a variety of highly polarized sensory and non-sensory cells are responsible for the early stages of sound processing in the ear, yet little is known about the mechanisms that traffic and organize signaling complexes within these cells. We sought to determine the prevalence, localization, and protein composition of cholesterol-rich lipid microdomains in the cochlea. Lipid raft components, including the scaffolding protein caveolin and the ganglioside GM1, were found in sensory, neural, and glial cells. Mass spectrometry of detergent-resistant membrane (DRM) fractions revealed over 600 putative raft proteins associated with subcellular localization, trafficking, and metabolism. Among the DRM constituents were several proteins involved in human forms of deafness including those involved in ion homeostasis, such as the potassium channel KCNQ1, the co-transporter SLC12A2, and gap junction proteins GJA1 and GJB6. The presence of caveolin in the cochlea and the abundance of proteins in cholesterol-rich DRM suggest that lipid microdomains play a significant role in cochlear physiology. BIOLOGICAL SIGNIFICANCE Although mechanisms underlying cholesterol synthesis, homeostasis, and compartmentalization in the ear are poorly understood, there are several lines of evidence indicating that cholesterol is a key modulator of cochlear function. Depletion of cholesterol in mature sensory cells alters calcium signaling, changes excitability during development, and affects the biomechanical processes in outer hair cells that are responsible for hearing acuity. More recently, we have established that the cholesterol-modulator beta-cyclodextrin is capable of inducing significant and permanent hearing loss when delivered subcutaneously at high doses. We hypothesize that proteins involved in cochlear homeostasis and otopathology are partitioned into cholesterol-rich domains. The results of a large-scale proteomic analysis point to metabolic processes, scaffolding/trafficking, and ion homeostasis as particularly associated with cholesterol microdomains. These data offer insight into the proteins and protein families that may underlie cholesterol-mediated effects in sensory cell excitability and cyclodextrin ototoxicity.
Collapse
Affiliation(s)
- Paul V Thomas
- Kresge Hearing Research Institute, 5323 Medical Science Building I, 1150 West Medical Center Drive, The University of Michigan, Ann Arbor, MI 48109-5616, USA
| | - Andrew L Cheng
- Kresge Hearing Research Institute, 5323 Medical Science Building I, 1150 West Medical Center Drive, The University of Michigan, Ann Arbor, MI 48109-5616, USA
| | - Candice C Colby
- Kresge Hearing Research Institute, 5323 Medical Science Building I, 1150 West Medical Center Drive, The University of Michigan, Ann Arbor, MI 48109-5616, USA
| | - Liqian Liu
- Kresge Hearing Research Institute, 5323 Medical Science Building I, 1150 West Medical Center Drive, The University of Michigan, Ann Arbor, MI 48109-5616, USA
| | - Chintan K Patel
- Kresge Hearing Research Institute, 5323 Medical Science Building I, 1150 West Medical Center Drive, The University of Michigan, Ann Arbor, MI 48109-5616, USA
| | - Lydia Josephs
- Kresge Hearing Research Institute, 5323 Medical Science Building I, 1150 West Medical Center Drive, The University of Michigan, Ann Arbor, MI 48109-5616, USA
| | - R Keith Duncan
- Kresge Hearing Research Institute, 5323 Medical Science Building I, 1150 West Medical Center Drive, The University of Michigan, Ann Arbor, MI 48109-5616, USA.
| |
Collapse
|
15
|
Panfoli I, Ravera S, Bruschi M, Candiano G, Morelli A. Proteomics unravels the exportability of mitochondrial respiratory chains. Expert Rev Proteomics 2014; 8:231-9. [DOI: 10.1586/epr.11.1] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
|
16
|
Loza-Huerta A, Vera-Estrella R, Darszon A, Beltrán C. Certain Strongylocentrotus purpuratus sperm mitochondrial proteins co-purify with low density detergent-insoluble membranes and are PKA or PKC-substrates possibly involved in sperm motility regulation. Biochim Biophys Acta Gen Subj 2013; 1830:5305-15. [DOI: 10.1016/j.bbagen.2013.07.029] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2012] [Revised: 06/24/2013] [Accepted: 07/27/2013] [Indexed: 12/14/2022]
|
17
|
Ectopic F0F 1 ATP synthase contains both nuclear and mitochondrially-encoded subunits. J Bioenerg Biomembr 2013; 45:569-79. [PMID: 23943123 DOI: 10.1007/s10863-013-9522-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2013] [Accepted: 07/14/2013] [Indexed: 12/11/2022]
Abstract
Over the past few years, several reports have described the presence of F0F1 ATP synthase subunits at the surface of hepatocytes, where the hydrolytic activity of F1 sector faces outside and triggers HDL endocytosis. An intriguing question is whether the ectopic enzyme has same subunit composition and molecular mass as that of the mitochondrial ATP synthase. Also due to the polar nature of hepatocytes, the enzyme may be localized to a particular cell boundary. Using different methods to prepare rat liver plasma membranes, which have been subjected to digitonin extraction, hr CN PAGE, immunoblotting, and mass spectrometry analysis, we demonstrate the presence of ecto-F0F1 complexes which have a similar molecular weight to the monomeric form of the mitochondrial complexes, containing both nuclear and mitochondrially-encoded subunits. This finding makes it unlikely that the enzyme assembles on the plasma membranes, but suggest it to be transported whole after being assembled in mitochondria by still unknown pathways. Moreover, the plasma membrane preparation enriched in basolateral proteins contains much higher amounts of complete and active F0F1 complexes, consistent with their specific function to modulate the HDL uptake on hepatocyte surface.
Collapse
|
18
|
Wu Q, Wu S. Lipid rafts association and anti-apoptotic function of prohibitin in ultraviolet B light-irradiated HaCaT keratinocytes. Exp Dermatol 2012; 21:640-2. [PMID: 22776003 DOI: 10.1111/j.1600-0625.2012.01547.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Upon UVB irradiation, an alternation of major lipid raft components can lead to the recruitment/activation of rafts-associated proteins and initiation of downstream apoptotic signalling pathways. We used two-dimensional gel electrophoresis (2-DE) to identify potential regulators of UVB-induced apoptosis and mass spectrometry fingerprint analysis to identify proteins that are altered in the rafts after UVB irradiation. Our data show that levels of several proteins, including prohibitin (PHB), were changed in lipid rafts after UVB irradiation. We also demonstrate that while total PHB expression was not changed, the protein was enriched in lipid rafts after UVB irradiation. Reduced expression of PHB using siRNA knockdown resulted in an increase in cellular apoptosis after UVB irradiation. Based on these results, we propose that PHB protects keratinocytes from UVB-induced apoptosis.
Collapse
Affiliation(s)
- Qiong Wu
- Department of Chemistry and Biochemistry, Edison Biotechnology Institute, Ohio University, Athens, OH, USA
| | | |
Collapse
|
19
|
Koh J, Chen S, Zhu N, Yu F, Soltis PS, Soltis DE. Comparative proteomics of the recently and recurrently formed natural allopolyploid Tragopogon mirus (Asteraceae) and its parents. THE NEW PHYTOLOGIST 2012; 196:292-305. [PMID: 22861377 DOI: 10.1111/j.1469-8137.2012.04251.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
• We examined the proteomes of the recently formed natural allopolyploid Tragopogon mirus and its diploid parents (T. dubius, T. porrifolius), as well as a diploid F(1) hybrid and synthetic T. mirus. • Analyses using iTRAQ LC-MS/MS technology identified 476 proteins produced by all three species. Of these, 408 proteins showed quantitative additivity of the two parental profiles in T. mirus (both natural and synthetic); 68 proteins were quantitatively differentially expressed. • Comparison of F(1) hybrid, and synthetic and natural polyploid T. mirus with the parental diploid species revealed 32 protein expression changes associated with hybridization, 22 with genome doubling and 14 that had occurred since the origin of T. mirus c. 80 yr ago. We found six proteins with novel expression; this phenomenon appears to start in the F(1) hybrid and results from post-translational modifications. • Our results indicate that the impact of hybridization on the proteome is more important than is polyploidization. Furthermore, two cases of homeolog-specific expression in T. mirus suggest that silencing in T. mirus was not associated with hybridization itself, but occurred subsequent to both hybridization and polyploidization. This study has shown the utility of proteomics in the analysis of the evolutionary consequences of polyploidy.
Collapse
Affiliation(s)
- Jin Koh
- Department of Biology, University of Florida, Gainesville, FL 32611, USA
- Interdisciplinary Center for Biotechnology Research, University of Florida, PO Box 103622, Gainesville, FL 32610, USA
| | - Sixue Chen
- Department of Biology, University of Florida, Gainesville, FL 32611, USA
- Interdisciplinary Center for Biotechnology Research, University of Florida, PO Box 103622, Gainesville, FL 32610, USA
- Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| | - Ning Zhu
- Department of Biology, University of Florida, Gainesville, FL 32611, USA
| | - Fahong Yu
- Interdisciplinary Center for Biotechnology Research, University of Florida, PO Box 103622, Gainesville, FL 32610, USA
| | - Pamela S Soltis
- Genetics Institute, University of Florida, Gainesville, FL 32610, USA
- Florida Museum of Natural History, University of Florida, Gainesville, FL 32611, USA
| | - Douglas E Soltis
- Department of Biology, University of Florida, Gainesville, FL 32611, USA
- Genetics Institute, University of Florida, Gainesville, FL 32610, USA
| |
Collapse
|
20
|
Christie DA, Kirchhof MG, Vardhana S, Dustin ML, Madrenas J. Mitochondrial and plasma membrane pools of stomatin-like protein 2 coalesce at the immunological synapse during T cell activation. PLoS One 2012; 7:e37144. [PMID: 22623988 PMCID: PMC3356372 DOI: 10.1371/journal.pone.0037144] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Accepted: 04/13/2012] [Indexed: 01/29/2023] Open
Abstract
Stomatin-like protein 2 (SLP-2) is a member of the stomatin-prohibitin-flotillin-HflC/K (SPFH) superfamily. Recent evidence indicates that SLP-2 is involved in the organization of cardiolipin-enriched microdomains in mitochondrial membranes and the regulation of mitochondrial biogenesis and function. In T cells, this role translates into enhanced T cell activation. Although the major pool of SLP-2 is associated with mitochondria, we show here that there is an additional pool of SLP-2 associated with the plasma membrane of T cells. Both plasma membrane-associated and mitochondria-associated pools of SLP-2 coalesce at the immunological synapse (IS) upon T cell activation. SLP-2 is not required for formation of IS nor for the re-localization of mitochondria to the IS because SLP-2-deficient T cells showed normal re-localization of these organelles in response to T cell activation. Interestingly, upon T cell activation, we found the surface pool of SLP-2 mostly excluded from the central supramolecular activation complex, and enriched in the peripheral area of the IS where signalling TCR microclusters are located. Based on these results, we propose that SLP-2 facilitates the compartmentalization not only of mitochondrial membranes but also of the plasma membrane into functional microdomains. In this latter location, SLP-2 may facilitate the optimal assembly of TCR signalosome components. Our data also suggest that there may be a net exchange of membrane material between mitochondria and plasma membrane, explaining the presence of some mitochondrial proteins in the plasma membrane.
Collapse
Affiliation(s)
- Darah A. Christie
- The Centre for Human Immunology, Robarts Research Institute, and the Departments of Microbiology and Immunology, and Medicine, The University of Western Ontario, London, Ontario, Canada
| | - Mark G. Kirchhof
- The Centre for Human Immunology, Robarts Research Institute, and the Departments of Microbiology and Immunology, and Medicine, The University of Western Ontario, London, Ontario, Canada
| | - Santosh Vardhana
- Program in Molecular Pathogenesis, Skirball Institute of Biomolecular Medicine, New York, New York, United States of America
| | - Michael L. Dustin
- Program in Molecular Pathogenesis, Skirball Institute of Biomolecular Medicine, New York, New York, United States of America
| | - Joaquín Madrenas
- The Centre for Human Immunology, Robarts Research Institute, and the Departments of Microbiology and Immunology, and Medicine, The University of Western Ontario, London, Ontario, Canada
- Department of Microbiology and Immunology, McGill University, Montreal, Quebec, Canada
- * E-mail:
| |
Collapse
|
21
|
Guo W, Liu S, Peng J, Wei X, Sun Y, Qiu Y, Gao G, Wang P, Xu Y. Examining the interactome of huperzine A by magnetic biopanning. PLoS One 2012; 7:e37098. [PMID: 22615909 PMCID: PMC3353884 DOI: 10.1371/journal.pone.0037098] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2011] [Accepted: 04/18/2012] [Indexed: 11/25/2022] Open
Abstract
Huperzine A is a bioactive compound derived from traditional Chinese medicine plant Qian Ceng Ta (Huperzia serrata), and was found to have multiple neuroprotective effects. In addition to being a potent acetylcholinesterase inhibitor, it was thought to act through other mechanisms such as antioxidation, antiapoptosis, etc. However, the molecular targets involved with these mechanisms were not identified. In this study, we attempted to exam the interactome of Huperzine A using a cDNA phage display library and also mammalian brain tissue extracts. The drugs were chemically linked on the surface of magnetic particles and the interactive phages or proteins were collected and analyzed. Among the various cDNA expressing phages selected, one was identified to encode the mitochondria NADH dehydrogenase subunit 1. Specific bindings between the drug and the target phages and target proteins were confirmed. Another enriched phage clone was identified as mitochondria ATP synthase, which was also panned out from the proteome of mouse brain tissue lysate. These data indicated the possible involvement of mitochondrial respiratory chain matrix enzymes in Huperzine A's pharmacological effects. Such involvement had been suggested by previous studies based on enzyme activity changes. Our data supported the new mechanism. Overall we demonstrated the feasibility of using magnetic biopanning as a simple and viable method for investigating the complex molecular mechanisms of bioactive molecules.
Collapse
Affiliation(s)
- Wei Guo
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Shupeng Liu
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, People's Republic of China
- Institute of Biomedical Engineering, Shanghai University, Shanghai, People's Republic of China
| | - Jinliang Peng
- Med-X Research Institute, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Xiaohui Wei
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Ye Sun
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Yangsheng Qiu
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Guangwei Gao
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Peng Wang
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, People's Republic of China
| | - Yuhong Xu
- School of Pharmacy, Shanghai Jiao Tong University, Shanghai, People's Republic of China
- Med-X Research Institute, Shanghai Jiao Tong University, Shanghai, People's Republic of China
- * E-mail:
| |
Collapse
|
22
|
Hur JY, Teranishi Y, Kihara T, Yamamoto NG, Inoue M, Hosia W, Hashimoto M, Winblad B, Frykman S, Tjernberg LO. Identification of novel γ-secretase-associated proteins in detergent-resistant membranes from brain. J Biol Chem 2012; 287:11991-2005. [PMID: 22315232 DOI: 10.1074/jbc.m111.246074] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In Alzheimer disease, oligomeric amyloid β-peptide (Aβ) species lead to synapse loss and neuronal death. γ-Secretase, the transmembrane protease complex that mediates the final catalytic step that liberates Aβ from its precursor protein (APP), has a multitude of substrates, and therapeutics aimed at reducing Aβ production should ideally be specific for APP cleavage. It has been shown that APP can be processed in lipid rafts, and γ-secretase-associated proteins can affect Aβ production. Here, we use a biotinylated inhibitor for affinity purification of γ-secretase and associated proteins and mass spectrometry for identification of the purified proteins, and we identify novel γ-secretase-associated proteins in detergent-resistant membranes from brain. Furthermore, we show by small interfering RNA-mediated knockdown of gene expression that a subset of the γ-secretase-associated proteins, in particular voltage-dependent anion channel 1 (VDAC1) and contactin-associated protein 1 (CNTNAP1), reduced Aβ production (Aβ40 and Aβ42) by around 70%, whereas knockdown of presenilin 1, one of the essential γ-secretase complex components, reduced Aβ production by 50%. Importantly, these proteins had a less pronounced effect on Notch processing. We conclude that VDAC1 and CNTNAP1 associate with γ-secretase in detergent-resistant membranes and affect APP processing and suggest that molecules that interfere with this interaction could be of therapeutic use for Alzheimer disease.
Collapse
Affiliation(s)
- Ji-Yeun Hur
- Karolinska Institutet Dainippon Sumitomo Pharma Alzheimer Center, KI Alzheimer Disease Research Center, Department of Neurobiology, Karolinska Institutet, Novum, Huddinge SE-141 57, Sweden.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
23
|
Raimondo F, Morosi L, Chinello C, Perego R, Bianchi C, Albo G, Ferrero S, Rocco F, Magni F, Pitto M. Protein profiling of microdomains purified from renal cell carcinoma and normal kidney tissue samples. ACTA ACUST UNITED AC 2012; 8:1007-16. [DOI: 10.1039/c2mb05372a] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
|
24
|
Xie N, Huang K, Zhang T, Lei Y, Liu R, Wang K, Zhou S, Li J, Wu J, Wu H, Deng C, Zhao X, Nice EC, Huang C. Comprehensive proteomic analysis of host cell lipid rafts modified by HBV infection. J Proteomics 2012; 75:725-39. [DOI: 10.1016/j.jprot.2011.09.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2011] [Revised: 08/26/2011] [Accepted: 09/17/2011] [Indexed: 12/29/2022]
|
25
|
Secretion modification region-derived peptide disrupts HIV-1 Nef's interaction with mortalin and blocks virus and Nef exosome release. J Virol 2011; 86:406-19. [PMID: 22013042 DOI: 10.1128/jvi.05720-11] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Nef is secreted from infected cells in exosomes and is found in abundance in the sera of HIV-infected individuals. Secreted exosomal Nef (exNef) induces apoptosis in uninfected CD4⁺ T cells and may be a key component of HIV pathogenesis. The exosomal pathway has been implicated in HIV-1 virus release, suggesting a possible link between these two viral processes. However, the underlying mechanisms and cellular components of exNef secretion have not been elucidated. We have previously described a Nef motif, the secretion modification region (SMR; amino acids 66 to 70), that is required for exNef secretion. In silico modeling data suggest that this motif can form a putative binding pocket. We hypothesized that the Nef SMR binds a cellular protein involved in protein trafficking and that inhibition of this interaction would abrogate exNef secretion. By using tandem mass spectrometry and coimmunoprecipitation with a novel SMR-based peptide (SMRwt) that blocks exNef secretion and HIV-1 virus release, we identified mortalin as an SMR-specific cellular protein. A second set of coimmunoprecipitation experiments with full-length Nef confirmed that mortalin interacts with Nef via Nef's SMR motif and that this interaction is disrupted by the SMRwt peptide. Overexpression and microRNA knockdown of mortalin revealed a positive correlation between exNef secretion levels and mortalin protein expression. Using antibody inhibition we demonstrated that the Nef/mortalin interaction is necessary for exNef secretion. Taken together, this work constitutes a significant step in understanding the underlying mechanism of exNef secretion, identifies a novel host-pathogen interaction, and introduces an HIV-derived peptide with antiviral properties.
Collapse
|
26
|
Stomatin-like protein 2 binds cardiolipin and regulates mitochondrial biogenesis and function. Mol Cell Biol 2011; 31:3845-56. [PMID: 21746876 DOI: 10.1128/mcb.05393-11] [Citation(s) in RCA: 103] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Stomatin-like protein 2 (SLP-2) is a widely expressed mitochondrial inner membrane protein of unknown function. Here we show that human SLP-2 interacts with prohibitin-1 and -2 and binds to the mitochondrial membrane phospholipid cardiolipin. Upregulation of SLP-2 expression increases cardiolipin content and the formation of metabolically active mitochondrial membranes and induces mitochondrial biogenesis. In human T lymphocytes, these events correlate with increased complex I and II activities, increased intracellular ATP stores, and increased resistance to apoptosis through the intrinsic pathway, ultimately enhancing cellular responses. We propose that the function of SLP-2 is to recruit prohibitins to cardiolipin to form cardiolipin-enriched microdomains in which electron transport complexes are optimally assembled. Likely through the prohibitin functional interactome, SLP-2 then regulates mitochondrial biogenesis and function.
Collapse
|
27
|
Dolganiuc A. Role of lipid rafts in liver health and disease. World J Gastroenterol 2011; 17:2520-35. [PMID: 21633657 PMCID: PMC3103810 DOI: 10.3748/wjg.v17.i20.2520] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2011] [Revised: 02/24/2011] [Accepted: 03/03/2011] [Indexed: 02/06/2023] Open
Abstract
Liver diseases are an increasingly common cause of morbidity and mortality; new approaches for investigation of mechanisms of liver diseases and identification of therapeutic targets are emergent. Lipid rafts (LRs) are specialized domains of cellular membranes that are enriched in saturated lipids; they are small, mobile, and are key components of cellular architecture, protein partition to cellular membranes, and signaling events. LRs have been identified in the membranes of all liver cells, parenchymal and non-parenchymal; more importantly, LRs are active participants in multiple physiological and pathological conditions in individual types of liver cells. This article aims to review experimental-based evidence with regard to LRs in the liver, from the perspective of the liver as a whole organ composed of a multitude of cell types. We have gathered up-to-date information related to the role of LRs in individual types of liver cells, in liver health and diseases, and identified the possibilities of LR-dependent therapeutic targets in liver diseases.
Collapse
|
28
|
Kim KB, Yi JS, Nguyen N, Lee JH, Kwon YC, Ahn BY, Cho H, Kim YK, Yoo HJ, Lee JS, Ko YG. Cell-surface receptor for complement component C1q (gC1qR) is a key regulator for lamellipodia formation and cancer metastasis. J Biol Chem 2011; 286:23093-101. [PMID: 21536672 DOI: 10.1074/jbc.m111.233304] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
We previously demonstrated that the receptor for the complement component C1q (gC1qR) is a lipid raft protein that is indispensable for adipogenesis and insulin signaling. Here, we provide the first report that gC1qR is an essential component of lamellipodia in human lung carcinoma A549 cells. Cell-surface gC1qR was concentrated in the lamellipodia along with CD44, monosialoganglioside, actin, and phosphorylated focal adhesion kinase in cells stimulated with insulin, IGF-1, EGF, or serum. The growth factor-induced lamellipodia formation and cell migration were significantly decreased in gC1qR-depleted cells, with a concomitant blunt activation of the focal adhesion kinase and the respective receptor tyrosine kinases. Moreover, the gC1qR-depleted cells exhibited a reduced proliferation rate in culture as well as diminished tumorigenic and metastatic activities in grafted mice. We therefore conclude that cell-surface gC1qR regulates lamellipodia formation and metastasis via receptor tyrosine kinase activation.
Collapse
Affiliation(s)
- Ki-Bum Kim
- College of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Proteomic profiling of lipid rafts in a human breast cancer model of tumorigenic progression. Clin Exp Metastasis 2011; 28:529-40. [PMID: 21533873 DOI: 10.1007/s10585-011-9389-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Accepted: 04/10/2011] [Indexed: 12/27/2022]
Abstract
Tumor biomarkers assist in the early detection of cancer, act as therapeutic targets for intervention, and function as diagnostic indicators for the evaluation of therapeutic responses. To identify novel human breast cancer biomarkers, we have analyzed the protein content of lipid rafts isolated from a series of human mammary epithelial cell lines with increasing tumorigenic potential. Since lipid rafts function as platforms for protein interaction critical to several biological processes, we hypothesized that the abundance of proteins associated with proliferation, invasion and metastasis would be dysregulated in highly transformed cells. For this purpose, the MCF10A epithelial lineage, which include benign MCF10A cells, premalignant AT and TG3B cells, and malignant CA1a tumor cells, was utilized. Detergent-resistant membranes were isolated from each line and proteins were identified and relatively quantitated using iTRAQ™ reagents and tandem mass spectrometry. 57 proteins were identified, and 1667 peptide identifications, mapping to 49 proteins, contained sufficient information for semi-quantitative analysis. When comparing malignant to benign cells, we observed consistent alterations in groups of proteins, such as a 5.7-fold average decrease in G protein content (n = 5), 2.7-fold decrease in glycosylphosphatidylinositol-linked proteins (n = 7) and 3.3-fold increase in intermediate filaments (n = 9). Several of the identified proteins, including caveolin-1, filamin A, keratins 5, 6 and 17, and vimentin, are bona fide or candidate biomarkers in clinical studies, underscoring the usefulness of the MCF10A series as a model to better understand the biological mechanisms underlying cancer progression.
Collapse
|
30
|
Dong P, Flores J, Pelton K, Solomon KR. Prohibitin is a cholesterol-sensitive regulator of cell cycle transit. J Cell Biochem 2011; 111:1367-74. [PMID: 20830747 DOI: 10.1002/jcb.22865] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Cholesterol is essential in establishing most functional animal cell membranes; cells cannot grow or proliferate in the absence of sufficient cholesterol. Consequently, almost every cell, tissue, and animal tightly regulates cholesterol homeostasis, including complex mechanisms of synthesis, transport, uptake, and disposition of cholesterol molecules. We hypothesize that cellular recognition of cholesterol insufficiency causes cell cycle arrest in order to avoid a catastrophic failure in membrane synthesis. Here, we demonstrate using unbiased proteomics and standard biochemistry that cholesterol insufficiency causes upregulation of prohibitin, an inhibitor of cell cycle progression, through activation of a cholesterol-responsive promoter element. We also demonstrate that prohibitin protects cells from apoptosis caused by cholesterol insufficiency. This is the first study tying cholesterol homeostasis to a specific cell cycle regulator that inhibits apoptosis.
Collapse
Affiliation(s)
- Pei Dong
- Department of Orthopaedic Surgery, Children's Hospital Boston, 300 Longwood Avenue, Boston, Massachusetts 02115, USA
| | | | | | | |
Collapse
|
31
|
Kim BW, Lee CS, Yi JS, Lee JH, Lee JW, Choo HJ, Jung SY, Kim MS, Lee SW, Lee MS, Yoon G, Ko YG. Lipid raft proteome reveals that oxidative phosphorylation system is associated with the plasma membrane. Expert Rev Proteomics 2011; 7:849-66. [PMID: 21142887 DOI: 10.1586/epr.10.87] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Although accumulating proteomic analyses have supported the fact that mitochondrial oxidative phosphorylation (OXPHOS) complexes are localized in lipid rafts, which mediate cell signaling, immune response and host-pathogen interactions, there has been no in-depth study of the physiological functions of lipid-raft OXPHOS complexes. Here, we show that many subunits of OXPHOS complexes were identified from the lipid rafts of human adipocytes, C2C12 myotubes, Jurkat cells and surface biotin-labeled Jurkat cells via shotgun proteomic analysis. We discuss the findings of OXPHOS complexes in lipid rafts, the role of the surface ATP synthase complex as a receptor for various ligands and extracellular superoxide generation by plasma membrane oxidative phosphorylation complexes.
Collapse
Affiliation(s)
- Bong-Woo Kim
- College of Life Sciences and Biotechnology, Korea University, 1, 5-ka, Anam-dong, Sungbuk-ku, Seoul, Korea
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Wu YP, Chang CM, Hung CY, Tsai MC, Schuyler SC, Wang RYL. Japanese encephalitis virus co-opts the ER-stress response protein GRP78 for viral infectivity. Virol J 2011; 8:128. [PMID: 21418596 PMCID: PMC3071342 DOI: 10.1186/1743-422x-8-128] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2011] [Accepted: 03/20/2011] [Indexed: 12/19/2022] Open
Abstract
The serum-free medium from Japanese encephalitis virus (JEV) infected Baby Hamster Kidney-21 (BHK-21) cell cultures was analyzed by liquid chromatography tandem mass spectrometry (LC-MS) to identify host proteins that were secreted upon viral infection. Five proteins were identified, including the molecular chaperones Hsp90, GRP78, and Hsp70. The functional role of GRP78 in the JEV life cycle was then investigated. Co-migration of GRP78 with JEV particles in sucrose density gradients was observed and co-localization of viral E protein with GRP78 was detected by immunofluorescence analysis in vivo. Knockdown of GRP78 expression by siRNA did not effect viral RNA replication, but did impair mature viral production. Mature viruses that do not co-fractionate with GPR78 displayed a significant decrease in viral infectivity. Our results support the hypothesis that JEV co-opts host cell GPR78 for use in viral maturation and in subsequent cellular infections.
Collapse
Affiliation(s)
- Yi-Ping Wu
- Department of Biomedical Sciences, Chang Gung University, TaoYuan, 33302, Taiwan
| | | | | | | | | | | |
Collapse
|
33
|
Freeman KW, Bowman BR, Zetter BR. Regenerative protein thymosin beta-4 is a novel regulator of purinergic signaling. FASEB J 2011; 25:907-15. [PMID: 21106936 DOI: 10.1096/fj.10-169417] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2023]
Abstract
By an unknown mechanism, β-thymosins are extracellular modulators of angiogenesis, inflammation, wound healing, and development. We were interested in identifying β-thymosin interactors and determining their importance in β-thymosins signaling in human vein endothelial cells (HUVECs). We performed pulldown experiments with biotinylated thymosin β-4 (Tβ4) in comparison to neutravidin beads alone and used mass spectrometric analysis to identify differentially interacting proteins. By this method, we identified F1-F0 ATP synthase, a known target of antiangiogenic angiostatin. By surface plasmon resonance, we determined for Tβ4 binding to the β subunit of ATP synthase a K(D) of 12 nM. Blocking antibodies and antagonists (oligomycin, IC(50) ∼1.8 μM; piceatannol, IC(50) ∼1.05 μM; and angiostatin, IC(50) ∼2.9 μg/ml) of ATP synthase inhibited the Tβ4-induced increase in cell surface ATP levels, as measured by luciferase assay, and the Tβ4-induced increase in HUVEC migration, as measured by transwell migration assay. Silencing of the ATP-responsive purinergic receptor P2X4 with siRNA also blocked Tβ4-induced HUVEC migration in a transwell assay. Furthermore, in silico we identified common amphiphilic α-helical structural similarities between β-thymosins and the inhibitory factor 1 (IF1), an inhibitor of ATP synthase hydrolysis. In summary, we have identified an extracellular signaling pathway where Tβ4 increases cell surface ATP levels via ATP synthase and have shown further that ATP-responsive P2X4 receptor is required for Tβ4-induced HUVEC migration.
Collapse
Affiliation(s)
- Kevin W Freeman
- Vascular Biology Program and Department of Surgery, Children's Hospital, Boston, MA 02115, USA
| | | | | |
Collapse
|
34
|
Ravera S, Aluigi MG, Calzia D, Ramoino P, Morelli A, Panfoli I. Evidence for Ectopic Aerobic ATP Production on C6 Glioma Cell Plasma Membrane. Cell Mol Neurobiol 2010; 31:313-21. [DOI: 10.1007/s10571-010-9624-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2010] [Accepted: 10/20/2010] [Indexed: 01/26/2023]
|
35
|
Ponce J, Brea D, Carrascal M, Guirao V, Degregorio-Rocasolano N, Sobrino T, Castillo J, Dávalos A, Gasull T. The effect of simvastatin on the proteome of detergent-resistant membrane domains: decreases of specific proteins previously related to cytoskeleton regulation, calcium homeostasis and cell fate. Proteomics 2010; 10:1954-65. [PMID: 20217863 DOI: 10.1002/pmic.200900055] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Cell death induced by over-activation of glutamate receptors occurs in different neuropathologies. Cholesterol depletors protect from neurotoxic over-activation of glutamate receptors, and we have recently reported that this neuroprotection is associated with a reduction of the N-methyl-D-aspartate subtype of glutamate receptors in detergent-resistant membrane domains (DRM). In the present study we used comparative proteomics to further identify which proteins, besides the N-methyl-D-aspartate receptor, change its percentage of association to DRM after treatment of neurons with simvastatin. We detected 338 spots in neuronal DRM subjected to 2-DE; eleven of these spots changed its intensity after treatment with simvastatin. All 11 differential spots showed reduced intensity in simvastatin-treated samples and were identified as adipocyte plasma membrane associated protein, enolase, calretinin, coronin 1a, f-actin capping protein alpha1, f-actin capping protein alpha2, heat shock cognate protein 71, malate dehydrogenase, n-myc downregulated gene 1, prohibitin 2, Rab GDP dissociation inhibitor, translationally controlled tumor protein and voltage dependent anion selective channel protein 1. The proteins tested colocalized with the lipid raft marker caveolin-1. Interestingly, the proteins we have identified in the present study had been previously reported to play a role in cell fate and, thus, they might represent novel targets for neuroprotection.
Collapse
Affiliation(s)
- Jovita Ponce
- Cellular and Molecular Neurobiology Research Group and Grup de Recerca en Neurociencies del IGTP, Department of Neurosciences, Fundació Institut d'Investigació en Ciències de la Salut Germans Trias I Pujol-Universitat Autónoma de Barcelona, Badalona, Spain
| | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Ma Z, Cao M, Liu Y, He Y, Wang Y, Yang C, Wang W, Du Y, Zhou M, Gao F. Mitochondrial F1Fo-ATP synthase translocates to cell surface in hepatocytes and has high activity in tumor-like acidic and hypoxic environment. Acta Biochim Biophys Sin (Shanghai) 2010; 42:530-7. [PMID: 20705594 DOI: 10.1093/abbs/gmq063] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
F1Fo-ATP synthase was originally thought to exclusively locate in the inner membrane of the mitochondria. However, recent studies prove the existence of ectopic F1Fo-ATP synthase on the outside of the cell membrane. Ectopic ATP synthase was proposed as a marker for tumor target therapy. Nevertheless, the protein transport mechanism of the ectopic ATP synthase is still unclear. The specificity of the ectopic ATP synthase, with regard to tumors, is questioned because of its widespread expression. In the current study, we constructed green fluorescent protein-ATP5B fusion protein and introduced it into HepG2 cells to study the localization of the ATP synthase. The expression of ATP5B was analyzed in six cell lines with different 'malignancies'. These cells were cultured in both normal and tumor-like acidic and hypoxic conditions. The results suggested that the ectopic expression of ATP synthase is a consequence of translocation from the mitochondria. The expression and catalytic activity of ectopic ATP synthase were similar on the surface of malignant cells as on the surface of less malignant cells. Interestingly, the expression of ectopic ATP synthase was not up-regulated in tumor-like acidic and hypoxic microenvironments. However, the catalytic activity of ectopic ATP synthase was up-regulated in tumor-like microenvironments. Therefore, the specificity of ectopic ATP synthase for tumor target therapy relies on the high level of catalytic activity that is observed in acidic and hypoxic microenvironments in tumor tissues.
Collapse
Affiliation(s)
- Zhan Ma
- Department of Molecular Biology Laboratory, Shanghai Sixth People's Hospital Affiliated Shanghai Jiao Tong University School of Medicine, China
| | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Magnetic nanoparticle-based isolation of endocytic vesicles reveals a role of the heat shock protein GRP75 in macromolecular delivery. Proc Natl Acad Sci U S A 2010; 107:13342-7. [PMID: 20624969 DOI: 10.1073/pnas.1002622107] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
An increased understanding of cellular uptake mechanisms of macromolecules remains an important challenge in cell biology with implications for viral infection and macromolecular drug delivery. Here, we report a strategy based on antibody-conjugated magnetic nanoparticles for the isolation of endocytic vesicles induced by heparan sulfate proteoglycans (HSPGs), key cell-surface receptors of macromolecular delivery. We provide evidence for a role of the glucose-regulated protein (GRP)75/PBP74/mtHSP70/mortalin (hereafter termed "GRP75") in HSPG-mediated endocytosis of macromolecules. GRP75 was found to be a functional constituent of intracellular vesicles of a nonclathrin-, noncaveolin-dependent pathway that was sensitive to membrane cholesterol depletion and that showed colocalization with the membrane raft marker cholera toxin subunit B. We further demonstrate a functional role of the RhoA GTPase family member CDC42 in this transport pathway; however, the small GTPase dynamin appeared not to be involved. Interestingly, we provide evidence of a functional role of GRP75 using RNAi-mediated down-regulation of GRP75 and GRP75-blocking antibodies, both of which inhibited macromolecular endocytosis. We conclude that GRP75, a chaperone protein classically found in the endoplasmic reticulum and mitochondria, is a functional constituent of noncaveolar, membrane raft-associated endocytic vesicles. Our data provide proof of principle of a strategy that should be generally applicable in the molecular characterization of selected endocytic pathways involved in macromolecular uptake by mammalian cells.
Collapse
|
38
|
Shokolenko IN, Alexeyev MF, LeDoux SP, Wilson GL. The approaches for manipulating mitochondrial proteome. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2010; 51:451-461. [PMID: 20544885 PMCID: PMC3249350 DOI: 10.1002/em.20570] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Over the past decade a large volume of research data has accumulated which has established a fundamental role for mitochondria in normal cellular functioning, as well as in various pathologies. Mitochondria play a pivotal role in metabolism and energy production, and are one of the key players involved in programmed cell death. On the other hand, mitochondrial dysfunction is implicated, directly or indirectly in numerous pathological conditions including inherited mitochondrial disorders, diabetes, cardiovascular and neurodegenerative diseases, and a variety of malignancies. The ability to modulate mitochondrial function by altering the diverse protein component of this organelle may be of great value for developing future therapeutic interventions. This review will discuss approaches used to introduce proteins into mitochondria. One group of methods utilizes strategies aimed at expressing proteins from genes in the nucleus. These include overexpression of nuclear-encoded mitochondrial proteins, allotopic expression, which is the re-coding and relocation of mitochondrial genes to the nucleus for expression and subsequent delivery of their gene products to mitochondria, and xenotopic expression, which is the nuclear expression of genes coding electron transport chain components from distant species, for delivery of their products to mammalian mitochondria. Additionally, antigenomic and progenomic strategies which focus on expression of mitochondrially targeted nuclear proteins involved in the maintenance of mtDNA will be discussed. The second group of methods considered will focus on attempts to use purified proteins for mitochondrial delivery. Special consideration has been given to the complexities involved in targeting exogenous proteins to mitochondria.
Collapse
|
39
|
Kim BW, Lee JW, Choo HJ, Lee CS, Jung SY, Yi JS, Ham YM, Lee JH, Hong J, Kang MJ, Chi SG, Hyung SW, Lee SW, Kim HM, Cho BR, Min DS, Yoon G, Ko YG. Mitochondrial oxidative phosphorylation system is recruited to detergent-resistant lipid rafts during myogenesis. Proteomics 2010; 10:2498-515. [DOI: 10.1002/pmic.200900826] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
40
|
TRIM72 negatively regulates myogenesis via targeting insulin receptor substrate-1. Cell Death Differ 2010; 17:1254-65. [PMID: 20139895 DOI: 10.1038/cdd.2010.1] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Lipid rafts have been known to be platforms to initiate cellular signal transduction of insulin-like growth factor (IGF) inducing skeletal muscle differentiation and hypertrophy. Here, tripartite motif 72 (TRIM72), with a really interesting new gene (RING)-finger domain, a B-box, two coiled-coil domains, and a SPRY (SPla and RYanodine receptor) domain, was revealed to be predominantly expressed in the sarcolemma lipid rafts of skeletal and cardiac muscles. Adenoviral TRIM72 overexpression prevented but RNAi-mediated TRIM72 silencing enhanced C2C12 myogenesis by modulating the IGF-induced insulin receptor substrate-1 (IRS-1) activation through the molecular association of TRIM72 with IRS-1. Furthermore, myogenic activity was highly enhanced with increased IGF-induced Akt activation in the satellite cells of TRIM72(-/-) mice, compared to those of TRIM72+/+ mice. Because TRIM72 promoter analysis shows that two proximal E-boxes in TRIM72 promoter were essential for MyoD- and Akt-dependent TRIM72 transcription, we can conclude that TRIM72 is a novel antagonist of IRS-1, and is essential as a negative regulator of IGF-induced muscle differentiation.
Collapse
|
41
|
Kim KB, Byun HO, Han NK, Ko YG, Choi HD, Kim N, Pack JK, Lee JS. Two-dimensional electrophoretic analysis of radio-frequency radiation-exposed MCF7 breast cancer cells. JOURNAL OF RADIATION RESEARCH 2010; 51:205-213. [PMID: 20339255 DOI: 10.1269/jrr.09030] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Although many in vitro studies have previously been conducted to elucidate the biological effects of radio frequency (RF) radiation over the past decades, the existence and nature of any effects is still inconclusive. In an effort to further elucidate this question, we have monitored changes in protein expression profiles in RF-exposed MCF7 human breast cancer cells using two-dimensional gel electrophoresis. MCF7 cells were exposed to 849 MHz RF radiation for 1 h per day for three consecutive days at specific absorption rates (SARs) of either 2 W/Kg or 10 W/kg. During exposure, the temperature in the exposure chamber was kept in an isothermal condition. Twenty-four hours after the final RF exposure, the protein lysates from MCF cells were prepared and two-dimensional electrophoretic analyses were conducted. The protein expression profiles of the MCF cells were not significantly altered as the result of RF exposure. None of the protein spots on the two-dimensional electrophoretic gels showed reproducible changes in three independent experiments. To determine effect of RF radiation on protein expression profiles more clearly, three spots showing altered expression without reproducibility were identified using electrospray ionization tandem mass spectrometry analysis and their expressions were examined with RT-PCR and Western blot assays. There was no alteration in their mRNA and protein levels. As we were unable to observe any significant and reproducible changes in the protein expression profiles of the RF radiation-exposed MCF7 cells using high throughput and non-high throughput techniques, it seems unlikely that RF exposure modulates the protein expression profile.
Collapse
MESH Headings
- Adenocarcinoma/chemistry
- Adenocarcinoma/pathology
- Blotting, Western
- Breast Neoplasms/chemistry
- Breast Neoplasms/pathology
- Cell Line, Tumor/chemistry
- Cell Line, Tumor/radiation effects
- Cell Phone
- Electrophoresis, Gel, Two-Dimensional
- Female
- Gene Expression Regulation, Neoplastic/radiation effects
- Humans
- Neoplasm Proteins/analysis
- Neoplasm Proteins/biosynthesis
- Neoplasm Proteins/genetics
- RNA, Messenger/analysis
- RNA, Neoplasm/analysis
- Radio Waves
- Reproducibility of Results
- Reverse Transcriptase Polymerase Chain Reaction
- Spectrometry, Mass, Electrospray Ionization
- Tandem Mass Spectrometry
Collapse
Affiliation(s)
- Ki-Bum Kim
- School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea
| | | | | | | | | | | | | | | |
Collapse
|
42
|
Trusch M, Böhlick A, Hildebrand D, Lichtner B, Bertsch A, Kohlbacher O, Bachmann S, Schlüter H. Application of displacement chromatography for the analysis of a lipid raft proteome. J Chromatogr B Analyt Technol Biomed Life Sci 2009; 878:309-14. [PMID: 20015709 DOI: 10.1016/j.jchromb.2009.11.035] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2009] [Revised: 10/16/2009] [Accepted: 11/20/2009] [Indexed: 10/20/2022]
Abstract
Defining membrane proteomes is fundamental to understand the role of membrane proteins in biological processes and to find new targets for drug development. Usually multidimensional chromatography using step or gradient elution is applied for the separation of tryptic peptides of membrane proteins prior to their mass spectrometric analysis. Displacement chromatography (DC) offers several advantages that are helpful for proteome analysis. However, DC has so far been applied for proteomic investigations only in few cases. In this study we therefore applied DC in a multidimensional LC-MS approach for the separation and identification of membrane proteins located in cholesterol-enriched membrane microdomains (lipid rafts) obtained from rat kidney by density gradient centrifugation. The tryptic peptides were separated on a cation-exchange column in the displacement mode with spermine used as displacer. Fractions obtained from DC were analyzed using an HPLC-chip system coupled to an electrospray-ionization ion-trap mass spectrometer. This procedure yielded more than 400 highly significant peptide spectrum matches and led to the identification of more than 140 reliable protein hits within an established rat kidney lipid raft proteome. The majority of identified proteins were membrane proteins. In sum, our results demonstrate that DC is a suitable alternative to gradient elution separations for the identification of proteins via a multidimensional LC-MS approach.
Collapse
Affiliation(s)
- Maria Trusch
- Department of Clinical Chemistry, University Medical Center Hamburg-Eppendorf, Campus Forschung, Martinistr. 52, D-20246 Hamburg, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
43
|
Molecular chaperone BiP interacts with Borna disease virus glycoprotein at the cell surface. J Virol 2009; 83:12622-5. [PMID: 19776128 DOI: 10.1128/jvi.01201-09] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Borna disease virus (BDV) is characterized by highly neurotropic infection. BDV enters its target cells using virus surface glycoprotein (G), but the cellular molecules mediating this process remain to be elucidated. We demonstrate here that the N-terminal product of G, GP1, interacts with the 78-kDa chaperone protein BiP. BiP was found at the surface of BDV-permissive cells, and anti-BiP antibody reduced BDV infection as well as GP1 binding to the cell surface. We also reveal that BiP localizes at the synapse of neurons. These results indicate that BiP may participate in the cell surface association of BDV.
Collapse
|
44
|
Hynek R, Svensson B, Jensen ON, Barkholt V, Finnie C. The plasma membrane proteome of germinating barley embryos. Proteomics 2009; 9:3787-94. [DOI: 10.1002/pmic.200800745] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
|
45
|
Byun HO, Han NK, Lee HJ, Kim KB, Ko YG, Yoon G, Lee YS, Hong SI, Lee JS. Cathepsin D and eukaryotic translation elongation factor 1 as promising markers of cellular senescence. Cancer Res 2009; 69:4638-47. [PMID: 19487283 DOI: 10.1158/0008-5472.can-08-4042] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Induction of premature senescence may be a promising strategy for cancer treatment. However, biomarkers for senescent cancer cells are lacking. To identify such biomarkers, we performed comparative proteomic analysis of MCF7 human breast cancer cells undergoing cellular senescence in response to ionizing radiation (IR). IR-induced senescence was associated with up-regulation of cathepsin D (CD) and down-regulation of eukaryotic translation elongation factor 1beta2 (eEF1B2), as confirmed by Western blot. The other elongation factor, eukaryotic translation elongation factor 1alpha1 (eEF1A1), was also down-regulated. IR-induced senescence was associated with similar changes of CD and eEF1 (eEF1A1 and eEF1B2) levels in the HCT116 colon cancer cell line and the H460 lung cancer cell line. Up-regulation of CD and down-regulation of eEF1 seemed to be specific to senescence, as they were observed during cellular senescence induced by hydrogen peroxide or anticancer drugs (camptothecin, etoposide, or 50 ng doxorubicin) but not during apoptosis induced by Taxol or 10 microg doxorubicin or autophagy induced by tamoxifen. The same alterations in CD and eEF1A1 levels were observed during replicative senescence and Ras oncogene-induced senescence. Transient cell cycle arrest did not alter levels of eEF1 or CD. Chemical inhibition of CD (pepstatin A) and small interfering RNA-mediated knockdown of CD and eEF1 revealed that these factors participate in cell proliferation. Finally, the senescence-associated alteration in CD and eEF1 levels observed in cell lines was also observed in IR-exposed xenografted tumors. These findings show that CD and eEF1 are promising markers for the detection of cellular senescence induced by a variety of treatments.
Collapse
Affiliation(s)
- Hae-Ok Byun
- Divisions of Radiation Cancer Research, Korea Institute of Radiological and Medical Sciences, Seoul, Korea
| | | | | | | | | | | | | | | | | |
Collapse
|
46
|
Pienaar IS, Schallert T, Hattingh S, Daniels WMU. Behavioral and quantitative mitochondrial proteome analyses of the effects of simvastatin: implications for models of neural degeneration. J Neural Transm (Vienna) 2009; 116:791-806. [PMID: 19504041 DOI: 10.1007/s00702-009-0247-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2009] [Accepted: 05/15/2009] [Indexed: 01/20/2023]
Abstract
The 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor, simvastatin, is used for lowering elevated low-density lipoprotein cholesterol concentrations. This translates into reduced cardiovascular disease-related morbidity and mortality, while the drugs' anti-oxidant and anti-inflammatory properties have earmarked it as a potential treatment strategy against various neurological conditions. Statins have been shown to protect neurons from degeneration in a number of animal models. Although no mechanism completely explains the multiple benefits exerted by statins, emerging evidence suggests that in some degenerative and brain injury models, mitochondrial impairment may play a contributive rate. However, [corrected] evidence lacks to support a directly influencing role for statins on mitochondria-related proteins and motor behavior. Mitochondrial dysfunction may increase oxygen free radical production, which in turn leaves cells susceptible to energy failure, apoptosis and related events [corrected] which could prove fatal. The potential link between simvastatin treatment and mitochondrial function would be supported if key mitochondrial proteins were altered by simvastatin exposure. Using mass spectroscopy (MS), we identified 24 mitochondrial proteins that differed significantly (P < 0.05) in relative abundancy as a result of simvastatin treatment. The identified proteins represented many facets of mitochondrial integrity, with the majority forming part of the electron transport chain machinery, which is necessary for energy production. In a follow-up study, we then addressed whether simvastatin is capable of altering sensorimotor function in a mitochondrial toxin-induced animal model. Rats were pre-treated with simvastatin for 14 days, followed by a single unihemispheric (substantia nigra; SN) injection of rotenone, a mitochondrial complex I (Co-I) inhibitor. Results showed that simvastatin improved motor performance in rotenone-infused rats. The data are consistent with the possibility that alteration of mitochondrial function may contribute to the beneficial effects associated with statin use.
Collapse
Affiliation(s)
- Ilse S Pienaar
- MRC Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford OX1 3QX, UK.
| | | | | | | |
Collapse
|
47
|
Proteomic analysis of membrane microdomain-associated proteins in the dorsolateral prefrontal cortex in schizophrenia and bipolar disorder reveals alterations in LAMP, STXBP1 and BASP1 protein expression. Mol Psychiatry 2009; 14:601-13. [PMID: 18268500 DOI: 10.1038/mp.2008.7] [Citation(s) in RCA: 136] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The dorsolateral prefrontal cortex (dlpfc) is strongly implicated in the pathogenesis of schizophrenia (SCZ) and bipolar disorder (BPD) and, within this region, abnormalities in glutamatergic neurotransmission and synaptic function have been described. Proteins associated with these functions are enriched in membrane microdomains (MM). In the current study, we used two complementary proteomic methods, two-dimensional difference gel electrophoresis and one-dimensional sodium dodecyl sulphate polyacrylamide gel electrophoresis followed by reverse phase-liquid chromatography-tandem mass spectrometry (RP-LC-MS/MS) (gel separation liquid chromatography-tandem mass spectrometry (GeLC-MS/MS)) to assess protein expression in MM in pooled samples of dlpfc from SCZ, BPD and control cases (n=10 per group) from the Stanley Foundation Brain series. We identified 16 proteins altered in one/both disorders using proteomic methods. We selected three proteins with roles in synaptic function (syntaxin-binding protein 1 (STXBP1), brain abundant membrane-attached signal protein 1 (BASP1) and limbic system-associated membrane protein (LAMP)) for validation by western blotting. This revealed significantly increased expression of these proteins in SCZ (STXBP1 (24% difference; P<0.001), BASP1 (40% difference; P<0.05) and LAMP (22% difference; P<0.01)) and BPD (STXBP1 (31% difference; P<0.001), BASP1 (23% difference; P<0.01) and LAMP (20% difference; P<0.01)) in the Stanley brain series (n=20 per group). Further validation in dlpfc from the Harvard brain subseries (n=10 per group) confirmed increased protein expression in SCZ of STXBP1 (18% difference; P<0.0001), BASP1 (14% difference; P<0.0001) but not LAMP (20% difference; P=0.14). No significant differences in STXBP1, BASP1 or LAMP protein expression in BPD dlpfc were observed. This study, through proteomic assessments of MM in dlpfc and validation in two brain series, strongly implicates LAMP, STXBP1 and BASP1 in SCZ and supports the view of a neuritic and synaptic dysfunction in the neuropathology of SCZ.
Collapse
|
48
|
Staubach S, Razawi H, Hanisch FG. Proteomics of MUC1-containing lipid rafts from plasma membranes and exosomes of human breast carcinoma cells MCF-7. Proteomics 2009; 9:2820-35. [DOI: 10.1002/pmic.200800793] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
49
|
Kim KB, Kim BW, Choo HJ, Kwon YC, Ahn BY, Choi JS, Lee JS, Ko YG. Proteome analysis of adipocyte lipid rafts reveals that gC1qR plays essential roles in adipogenesis and insulin signal transduction. Proteomics 2009; 9:2373-82. [DOI: 10.1002/pmic.200800811] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
50
|
Lippe G, Bisetto E, Comelli M, Contessi S, Di Pancrazio F, Mavelli I. Mitochondrial and cell-surface F0F1ATPsynthase in innate and acquired cardioprotection. J Bioenerg Biomembr 2009; 41:151-7. [PMID: 19387805 DOI: 10.1007/s10863-009-9208-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Mitochondria are central to heart function and dysfunction, and the pathways activated by different cardioprotective interventions mostly converge on mitochondria. In a context of perspectives in innate and acquired cardioprotection, we review some recent advances in F(0)F(1)ATPsynthase structure/function and regulation in cardiac cells. We focus on three topics regarding the mitochondrial F(0)F(1)ATPsynthase and the plasma membrane enzyme, i.e.: i) the crucial role of cardiac mitochondrial F(0)F(1)ATPsynthase regulation by the inhibitory protein IF(1) in heart preconditioning strategies; ii) the structure and function of mitochondrial F(0)F(1)ATPsynthase oligomers in mammalian myocardium as possible endogenous factors of mitochondria resistance to ischemic insult; iii) the external location and characterization of plasma membrane F(0)F(1) ATP synthase in search for possible actors of its regulation, such as IF(1) and calmodulin, at cell surface.
Collapse
Affiliation(s)
- Giovanna Lippe
- Department of Biomedical Sciences and Technologies and M.A.T.I. Centre of Excellence, University of Udine, P.le Kolbe 4, 33100, Udine, Italy
| | | | | | | | | | | |
Collapse
|