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Landowski M, Gogoi P, Ikeda S, Ikeda A. Roles of transmembrane protein 135 in mitochondrial and peroxisomal functions - implications for age-related retinal disease. FRONTIERS IN OPHTHALMOLOGY 2024; 4:1355379. [PMID: 38576540 PMCID: PMC10993500 DOI: 10.3389/fopht.2024.1355379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/06/2024]
Abstract
Aging is the most significant risk factor for age-related diseases in general, which is true for age-related diseases in the eye including age-related macular degeneration (AMD). Therefore, in order to identify potential therapeutic targets for these diseases, it is crucial to understand the normal aging process and how its mis-regulation could cause age-related diseases at the molecular level. Recently, abnormal lipid metabolism has emerged as one major aspect of age-related symptoms in the retina. Animal models provide excellent means to identify and study factors that regulate lipid metabolism in relation to age-related symptoms. Central to this review is the role of transmembrane protein 135 (TMEM135) in the retina. TMEM135 was identified through the characterization of a mutant mouse strain exhibiting accelerated retinal aging and positional cloning of the responsible mutation within the gene, indicating the crucial role of TMEM135 in regulating the normal aging process in the retina. Over the past decade, the molecular functions of TMEM135 have been explored in various models and tissues, providing insights into the regulation of metabolism, particularly lipid metabolism, through its action in multiple organelles. Studies indicated that TMEM135 is a significant regulator of peroxisomes, mitochondria, and their interaction. Here, we provide an overview of the molecular functions of TMEM135 which is crucial for regulating mitochondria, peroxisomes, and lipids. The review also discusses the age-dependent phenotypes in mice with TMEM135 perturbations, emphasizing the importance of a balanced TMEM135 function for the health of the retina and other tissues including the heart, liver, and adipose tissue. Finally, we explore the potential roles of TMEM135 in human age-related retinal diseases, connecting its functions to the pathobiology of AMD.
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Affiliation(s)
- Michael Landowski
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, United States
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, United States
| | - Purnima Gogoi
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, United States
| | - Sakae Ikeda
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, United States
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, United States
| | - Akihiro Ikeda
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, United States
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, United States
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Singin Ö, Astapenka A, Costina V, Kühl S, Bonekamp N, Drews O, Islinger M. Analysis of the Mouse Hepatic Peroxisome Proteome-Identification of Novel Protein Constituents Using a Semi-Quantitative SWATH-MS Approach. Cells 2024; 13:176. [PMID: 38247867 PMCID: PMC10814758 DOI: 10.3390/cells13020176] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Revised: 01/12/2024] [Accepted: 01/15/2024] [Indexed: 01/23/2024] Open
Abstract
Ongoing technical and bioinformatics improvements in mass spectrometry (MS) allow for the identifying and quantifying of the enrichment of increasingly less-abundant proteins in individual fractions. Accordingly, this study reassessed the proteome of mouse liver peroxisomes by the parallel isolation of peroxisomes from a mitochondria- and a microsome-enriched prefraction, combining density-gradient centrifugation with a semi-quantitative SWATH-MS proteomics approach to unveil novel peroxisomal or peroxisome-associated proteins. In total, 1071 proteins were identified using MS and assessed in terms of their distribution in either high-density peroxisomal or low-density gradient fractions, containing the bulk of organelle material. Combining the data from both fractionation approaches allowed for the identification of specific protein profiles characteristic of mitochondria, the ER and peroxisomes. Among the proteins significantly enriched in the peroxisomal cluster were several novel peroxisomal candidates. Five of those were validated by colocalization in peroxisomes, using confocal microscopy. The peroxisomal import of HTATIP2 and PAFAH2, which contain a peroxisome-targeting sequence 1 (PTS1), could be confirmed by overexpression in HepG2 cells. The candidates SAR1B and PDCD6, which are known ER-exit-site proteins, did not directly colocalize with peroxisomes, but resided at ER sites, which frequently surrounded peroxisomes. Hence, both proteins might concentrate at presumably co-purified peroxisome-ER membrane contacts. Intriguingly, the fifth candidate, OCIA domain-containing protein 1, was previously described as decreasing mitochondrial network formation. In this work, we confirmed its peroxisomal localization and further observed a reduction in peroxisome numbers in response to OCIAD1 overexpression. Hence, OCIAD1 appears to be a novel protein, which has an impact on both mitochondrial and peroxisomal maintenance.
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Affiliation(s)
- Öznur Singin
- Neuroanatomy, Mannheim Center for Translational Neuroscience, Medical Faculty Mannheim, Heidelberg University, D-68167 Mannheim, Germany; (Ö.S.); (A.A.); (S.K.); (N.B.)
| | - Artur Astapenka
- Neuroanatomy, Mannheim Center for Translational Neuroscience, Medical Faculty Mannheim, Heidelberg University, D-68167 Mannheim, Germany; (Ö.S.); (A.A.); (S.K.); (N.B.)
| | - Victor Costina
- Institute of Clinical Chemistry, Medical Faculty Mannheim, Heidelberg University, D-68167 Mannheim, Germany; (V.C.); (O.D.)
| | - Sandra Kühl
- Neuroanatomy, Mannheim Center for Translational Neuroscience, Medical Faculty Mannheim, Heidelberg University, D-68167 Mannheim, Germany; (Ö.S.); (A.A.); (S.K.); (N.B.)
| | - Nina Bonekamp
- Neuroanatomy, Mannheim Center for Translational Neuroscience, Medical Faculty Mannheim, Heidelberg University, D-68167 Mannheim, Germany; (Ö.S.); (A.A.); (S.K.); (N.B.)
| | - Oliver Drews
- Institute of Clinical Chemistry, Medical Faculty Mannheim, Heidelberg University, D-68167 Mannheim, Germany; (V.C.); (O.D.)
- Biomedical Mass Spectrometry, Center for Medical Research, Johannes Kepler University Linz, 4020 Linz, Austria
| | - Markus Islinger
- Neuroanatomy, Mannheim Center for Translational Neuroscience, Medical Faculty Mannheim, Heidelberg University, D-68167 Mannheim, Germany; (Ö.S.); (A.A.); (S.K.); (N.B.)
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Landowski M, Bhute VJ, Grindel S, Haugstad Z, Gyening YK, Tytanic M, Brush RS, Moyer LJ, Nelson DW, Davis CR, Yen CLE, Ikeda S, Agbaga MP, Ikeda A. Transmembrane protein 135 regulates lipid homeostasis through its role in peroxisomal DHA metabolism. Commun Biol 2023; 6:8. [PMID: 36599953 PMCID: PMC9813353 DOI: 10.1038/s42003-022-04404-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Accepted: 12/23/2022] [Indexed: 01/05/2023] Open
Abstract
Transmembrane protein 135 (TMEM135) is thought to participate in the cellular response to increased intracellular lipids yet no defined molecular function for TMEM135 in lipid metabolism has been identified. In this study, we performed a lipid analysis of tissues from Tmem135 mutant mice and found striking reductions of docosahexaenoic acid (DHA) across all Tmem135 mutant tissues, indicating a role of TMEM135 in the production of DHA. Since all enzymes required for DHA synthesis remain intact in Tmem135 mutant mice, we hypothesized that TMEM135 is involved in the export of DHA from peroxisomes. The Tmem135 mutation likely leads to the retention of DHA in peroxisomes, causing DHA to be degraded within peroxisomes by their beta-oxidation machinery. This may lead to generation or alteration of ligands required for the activation of peroxisome proliferator-activated receptor a (PPARa) signaling, which in turn could result in increased peroxisomal number and beta-oxidation enzymes observed in Tmem135 mutant mice. We confirmed this effect of PPARa signaling by detecting decreased peroxisomes and their proteins upon genetic ablation of Ppara in Tmem135 mutant mice. Using Tmem135 mutant mice, we also validated the protective effect of increased peroxisomes and peroxisomal beta-oxidation on the metabolic disease phenotypes of leptin mutant mice which has been observed in previous studies. Thus, we conclude that TMEM135 has a role in lipid homeostasis through its function in peroxisomes.
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Affiliation(s)
- Michael Landowski
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, USA
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, USA
| | - Vijesh J Bhute
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, USA
- Department of Chemical Engineering, Imperial College London, South Kensington, London, UK
| | - Samuel Grindel
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, USA
| | - Zachary Haugstad
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, USA
| | - Yeboah K Gyening
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Dean A. McGee Eye Institute, Oklahoma City, OK, USA
| | - Madison Tytanic
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Dean A. McGee Eye Institute, Oklahoma City, OK, USA
| | - Richard S Brush
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Dean A. McGee Eye Institute, Oklahoma City, OK, USA
| | - Lucas J Moyer
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, USA
| | - David W Nelson
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Christopher R Davis
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Chi-Liang Eric Yen
- Department of Nutritional Sciences, University of Wisconsin-Madison, Madison, WI, USA
| | - Sakae Ikeda
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, USA
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, USA
| | - Martin-Paul Agbaga
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
- Dean A. McGee Eye Institute, Oklahoma City, OK, USA
| | - Akihiro Ikeda
- Department of Medical Genetics, University of Wisconsin-Madison, Madison, WI, USA.
- McPherson Eye Research Institute, University of Wisconsin-Madison, Madison, WI, USA.
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Armstrong FA, Cheng B, Herold RA, Megarity CF, Siritanaratkul B. From Protein Film Electrochemistry to Nanoconfined Enzyme Cascades and the Electrochemical Leaf. Chem Rev 2022; 123:5421-5458. [PMID: 36573907 PMCID: PMC10176485 DOI: 10.1021/acs.chemrev.2c00397] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Protein film electrochemistry (PFE) has given unrivalled insight into the properties of redox proteins and many electron-transferring enzymes, allowing investigations of otherwise ill-defined or intractable topics such as unstable Fe-S centers and the catalytic bias of enzymes. Many enzymes have been established to be reversible electrocatalysts when attached to an electrode, and further investigations have revealed how unusual dependences of catalytic rates on electrode potential have stark similarities with electronics. A special case, the reversible electrochemistry of a photosynthetic enzyme, ferredoxin-NADP+ reductase (FNR), loaded at very high concentrations in the 3D nanopores of a conducting metal oxide layer, is leading to a new technology that brings PFE to myriad enzymes of other classes, the activities of which become controlled by the primary electron exchange. This extension is possible because FNR-based recycling of NADP(H) can be coupled to a dehydrogenase, and thence to other enzymes linked in tandem by the tight channelling of cofactors and intermediates within the nanopores of the material. The earlier interpretations of catalytic wave-shapes and various analogies with electronics are thus extended to initiate a field perhaps aptly named "cascade-tronics", in which the flow of reactions along an enzyme cascade is monitored and controlled through an electrochemical analyzer. Unlike in photosynthesis where FNR transduces electron transfer and hydride transfer through the unidirectional recycling of NADPH, the "electrochemical leaf" (e-Leaf) can be used to drive reactions in both oxidizing and reducing directions. The e-Leaf offers a natural way to study how enzymes are affected by nanoconfinement and crowding, mimicking the physical conditions under which enzyme cascades operate in living cells. The reactions of the trapped enzymes, often at very high local concentration, are thus studied electrochemically, exploiting the potential domain to control rates and direction and the current-rate analogy to derive kinetic data. Localized NADP(H) recycling is very efficient, resulting in very high cofactor turnover numbers and new opportunities for controlling and exploiting biocatalysis.
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Affiliation(s)
- Fraser A. Armstrong
- Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom
| | - Beichen Cheng
- Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom
| | - Ryan A. Herold
- Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom
| | - Clare F. Megarity
- Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom
| | - Bhavin Siritanaratkul
- Stephenson Institute for Renewable Energy and the Department of Chemistry, University of Liverpool, Liverpool L69 7ZF, United Kingdom
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Westhaver LP, Nersesian S, Nelson A, MacLean LK, Carter EB, Boudreau JE. Preparation of mitochondrial damage-associated molecular patterns from mouse liver tissue. STAR Protoc 2022; 3:101738. [PMID: 36183256 PMCID: PMC9529582 DOI: 10.1016/j.xpro.2022.101738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Revised: 07/15/2022] [Accepted: 09/08/2022] [Indexed: 01/26/2023] Open
Abstract
Mitochondrial damage-associated molecular patterns (mitoDAMPs) are released from cells dying uncontrolled, non-apoptotic deaths, usually secondary to disease or trauma. Here, we describe preparation of mitoDAMPs from mouse liver, but this protocol can be adapted for preparation of mitoDAMPs from other species and tissues. Tissues are dissociated and then processed to isolate mitochondria. Mitochondria are then sonicated and mitoDAMPs are collected by ultracentrifugation. This procedure produces μg quantities of mitoDAMPs and facilitates research to understand their impacts in health and disease. For complete details on the use and execution of this protocol, please refer to Westhaver et al. (2022).
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Affiliation(s)
- Lauren P. Westhaver
- Department of Pathology, Dalhousie University, Sir Charles Tupper Medical Building, 5850 College St., Halifax, NS B3H 4H7, Canada,Corresponding author
| | - Sarah Nersesian
- Department of Microbiology and Immunology, Dalhousie University, Room 7C, Sir Charles Tupper Medical Building, 5850 College St., Halifax, NS B3H 4H7, Canada,Beatrice Hunter Cancer Research Institute, Halifax, NS, Canada
| | - Adam Nelson
- Department of Microbiology and Immunology, Dalhousie University, Room 7C, Sir Charles Tupper Medical Building, 5850 College St., Halifax, NS B3H 4H7, Canada,Beatrice Hunter Cancer Research Institute, Halifax, NS, Canada
| | - Leah K. MacLean
- Department of Pathology, Dalhousie University, Sir Charles Tupper Medical Building, 5850 College St., Halifax, NS B3H 4H7, Canada,Beatrice Hunter Cancer Research Institute, Halifax, NS, Canada
| | - Emily B. Carter
- Department of Microbiology and Immunology, Dalhousie University, Room 7C, Sir Charles Tupper Medical Building, 5850 College St., Halifax, NS B3H 4H7, Canada,Beatrice Hunter Cancer Research Institute, Halifax, NS, Canada
| | - Jeanette E. Boudreau
- Department of Pathology, Dalhousie University, Sir Charles Tupper Medical Building, 5850 College St., Halifax, NS B3H 4H7, Canada,Department of Microbiology and Immunology, Dalhousie University, Room 7C, Sir Charles Tupper Medical Building, 5850 College St., Halifax, NS B3H 4H7, Canada,Beatrice Hunter Cancer Research Institute, Halifax, NS, Canada,Corresponding author
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Qin S, Zhang Y, Tian Y, Xu F, Zhang P. Subcellular metabolomics: Isolation, measurement, and applications. J Pharm Biomed Anal 2021; 210:114557. [PMID: 34979492 DOI: 10.1016/j.jpba.2021.114557] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 12/22/2021] [Accepted: 12/26/2021] [Indexed: 11/26/2022]
Abstract
Metabolomics, a technique that profiles global small molecules in biological samples, has been a pivotal tool for disease diagnosis and mechanism research. The sample type in metabolomics covers a wide range, including a variety of body fluids, tissues, and cells. However, little attention was paid to the smaller, relatively independent partition systems in cells, namely the organelles. The organelles are specific compartments/places where diverse metabolic activities are happening in an orderly manner. Metabolic disorders of organelles were found to occur in various pathological conditions such as inherited metabolic diseases, diabetes, cancer, and neurodegenerative diseases. However, at the cellular level, the metabolic outcomes of organelles and cytoplasm are superimposed interactively, making it difficult to describe the changes in subcellular compartments. Therefore, characterizing the metabolic pool in the compartmentalized system is of great significance for understanding the role of organelles in physiological functions and diseases. So far, there are very few research articles or reviews related to subcellular metabolomics. In this review, subcellular fractionation and metabolite analysis methods, as well as the application of subcellular metabolomics in the physiological and pathological studies are systematically reviewed, as a practical reference to promote the continued advancement in subcellular metabolomics.
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Affiliation(s)
- Siyuan Qin
- Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), State Key Laboratory of Natural Medicine, China Pharmaceutical University, Nanjing 210009, PR China
| | - Yuxin Zhang
- Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School, Nanjing, PR China
| | - Yuan Tian
- Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), State Key Laboratory of Natural Medicine, China Pharmaceutical University, Nanjing 210009, PR China
| | - Fengguo Xu
- Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), State Key Laboratory of Natural Medicine, China Pharmaceutical University, Nanjing 210009, PR China.
| | - Pei Zhang
- Key Laboratory of Drug Quality Control and Pharmacovigilance (Ministry of Education), State Key Laboratory of Natural Medicine, China Pharmaceutical University, Nanjing 210009, PR China.
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7
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Stastna M, Slais K. Preparative continuous flow electrophoretic instrumentation for purification of biological samples. Electrophoresis 2021; 42:2103-2111. [PMID: 34370314 DOI: 10.1002/elps.202100160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/20/2021] [Accepted: 08/02/2021] [Indexed: 11/11/2022]
Abstract
We constructed preparative instrumentation and developed the method that are based on separation of the samples by bidirectional isotachophoresis/moving boundary electrophoresis in continuous divergent flow. The described instrumentation can be used for variety of the samples, however, it can be easily optimized and tailored for the specific sample. The trapezoid separation bed from non-woven textile exhibited minimum adsorption effect for sample and it can be used repeatedly. By addition of different spacers via separation space inlets, the sections of pH gradient can be modified to enhance the separation. The liquid flow from two inlets positioned on each side of the sample inlet prevented the contact of the sample with anolyte and catholyte at the analysis beginning. One pair of thin electrodes (graphite and stainless-steel) was placed at the separation space output. The electrode products were washed out into drains without disturbing the focusing process. The influence of EOF was managed by tilting the separation bed in direction from cathodic to anodic side. The components of spirulina supernatant and color pI markers were separated in the pH gradient from 3.9 to 10.1. pH gradient was stable for at least 4.5 hours and spirulina supernatant from about 0.12 g of dry powder was processed. Compared to other preparative methods used for spirulina separation, the presented method/instrumentation working with continuous divergent flow had essential advantages. The efficient separation was fast, and no intermediate steps were necessary to obtain liquid fractions with separated components compatible with further biological experiments. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Miroslava Stastna
- Institute of Analytical Chemistry of the Czech Academy of Sciences, Brno, Czech Republic
| | - Karel Slais
- Institute of Analytical Chemistry of the Czech Academy of Sciences, Brno, Czech Republic
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Ray GJ, Boydston EA, Shortt E, Wyant GA, Lourido S, Chen WW, Sabatini DM. A PEROXO-Tag Enables Rapid Isolation of Peroxisomes from Human Cells. iScience 2020; 23:101109. [PMID: 32417403 PMCID: PMC7254474 DOI: 10.1016/j.isci.2020.101109] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 04/08/2020] [Accepted: 04/22/2020] [Indexed: 11/26/2022] Open
Abstract
Peroxisomes are metabolic organelles that perform a diverse array of critical functions in human physiology. Traditional isolation methods for peroxisomes can take more than 1 h to complete and can be laborious to implement. To address this, we have now extended our prior work on rapid organellar isolation to peroxisomes via the development of a peroxisomally localized 3XHA epitope tag ("PEROXO-Tag") and associated immunoprecipitation ("PEROXO-IP") workflow. Our PEROXO-IP workflow has excellent reproducibility, is easy to implement, and achieves highly rapid (~10 min post homogenization) and specific isolation of human peroxisomes, which we characterize here via proteomic profiling. By offering speed, specificity, reproducibility, and ease of use, the PEROXO-IP workflow should facilitate studies on the biology of peroxisomes.
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Affiliation(s)
- G Jordan Ray
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Department of Biology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA; Broad Institute of Harvard and Massachusetts Institute of Technology, 415 Main Street, Cambridge, MA 02142, USA
| | - Elizabeth A Boydston
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA
| | - Emily Shortt
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA
| | - Gregory A Wyant
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Department of Biology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA; Broad Institute of Harvard and Massachusetts Institute of Technology, 415 Main Street, Cambridge, MA 02142, USA
| | - Sebastian Lourido
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Walter W Chen
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Department of Biology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA; Broad Institute of Harvard and Massachusetts Institute of Technology, 415 Main Street, Cambridge, MA 02142, USA.
| | - David M Sabatini
- Whitehead Institute for Biomedical Research, 455 Main Street, Cambridge, MA 02142, USA; Howard Hughes Medical Institute, Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Department of Biology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA; Broad Institute of Harvard and Massachusetts Institute of Technology, 415 Main Street, Cambridge, MA 02142, USA.
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Van Veldhoven PP, de Schryver E, Young SG, Zwijsen A, Fransen M, Espeel M, Baes M, Van Ael E. Slc25a17 Gene Trapped Mice: PMP34 Plays a Role in the Peroxisomal Degradation of Phytanic and Pristanic Acid. Front Cell Dev Biol 2020; 8:144. [PMID: 32266253 PMCID: PMC7106852 DOI: 10.3389/fcell.2020.00144] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 02/20/2020] [Indexed: 12/04/2022] Open
Abstract
Mice lacking PMP34, a peroxisomal membrane transporter encoded by Slc25a17, did not manifest any obvious phenotype on a Swiss Webster genetic background, even with various treatments designed to unmask impaired peroxisomal functioning. Peroxisomal α- and β-oxidation rates in PMP34 deficient fibroblasts or liver slices were not or only modestly affected and in bile, no abnormal bile acid intermediates were detected. Peroxisomal content of cofactors like CoA, ATP, NAD+, thiamine-pyrophosphate and pyridoxal-phosphate, based on direct or indirect data, appeared normal as were tissue plasmalogen and very long chain fatty acid levels. However, upon dietary phytol administration, the knockout mice displayed hepatomegaly, liver inflammation, and an induction of peroxisomal enzymes. This phenotype was partially mediated by PPARα. Hepatic triacylglycerols and cholesterylesters were elevated and both phytanic acid and pristanic acid accumulated in the liver lipids, in females to higher extent than in males. In addition, pristanic acid degradation products were detected, as wells as the CoA-esters of all these branched fatty acids. Hence, PMP34 is important for the degradation of phytanic/pristanic acid and/or export of their metabolites. Whether this is caused by a shortage of peroxisomal CoA affecting the intraperoxisomal formation of pristanoyl-CoA (and perhaps of phytanoyl-CoA), or the SCPx-catalyzed thiolytic cleavage during pristanic acid β-oxidation, could not be proven in this model, but the phytol-derived acyl-CoA profile is compatible with the latter possibility. On the other hand, the normal functioning of other peroxisomal pathways, and especially bile acid formation, seems to exclude severe transport problems or a shortage of CoA, and other cofactors like FAD, NAD(P)+, TPP. Based on our findings, PMP34 deficiency in humans is unlikely to be a life threatening condition but could cause elevated phytanic/pristanic acid levels in older adults.
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Affiliation(s)
| | - Evelyn de Schryver
- LIPIT, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Stephen G. Young
- Departments of Medicine and Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA, United States
| | - An Zwijsen
- Laboratory of Developmental Signaling, Department Human Genetics, VIB-KU Leuven, Leuven, Belgium
| | - Marc Fransen
- LIPIT, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
| | - Marc Espeel
- Department of Anatomy, Embryology, Histology and Medical Physics, Ghent University, Ghent, Belgium
| | - Myriam Baes
- Laboratory of Cell Metabolism, Faculty of Pharmaceutical Sciences, KU Leuven, Leuven, Belgium
| | - Elke Van Ael
- LIPIT, Department of Cellular and Molecular Medicine, KU Leuven, Leuven, Belgium
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Ruiz M, Bodhicharla R, Ståhlman M, Svensk E, Busayavalasa K, Palmgren H, Ruhanen H, Boren J, Pilon M. Evolutionarily conserved long-chain Acyl-CoA synthetases regulate membrane composition and fluidity. eLife 2019; 8:47733. [PMID: 31769755 PMCID: PMC6901333 DOI: 10.7554/elife.47733] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 11/23/2019] [Indexed: 12/19/2022] Open
Abstract
The human AdipoR1 and AdipoR2 proteins, as well as their C. elegans homolog PAQR-2, protect against cell membrane rigidification by exogenous saturated fatty acids by regulating phospholipid composition. Here, we show that mutations in the C. elegans gene acs-13 help to suppress the phenotypes of paqr-2 mutant worms, including their characteristic membrane fluidity defects. acs-13 encodes a homolog of the human acyl-CoA synthetase ACSL1, and localizes to the mitochondrial membrane where it likely activates long chains fatty acids for import and degradation. Using siRNA combined with lipidomics and membrane fluidity assays (FRAP and Laurdan dye staining) we further show that the human ACSL1 potentiates lipotoxicity by the saturated fatty acid palmitate: silencing ACSL1 protects against the membrane rigidifying effects of palmitate and acts as a suppressor of AdipoR2 knockdown, thus echoing the C. elegans findings. We conclude that acs-13 mutations in C. elegans and ACSL1 knockdown in human cells prevent lipotoxicity by promoting increased levels of polyunsaturated fatty acid-containing phospholipids.
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Affiliation(s)
- Mario Ruiz
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Rakesh Bodhicharla
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Marcus Ståhlman
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Emma Svensk
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Kiran Busayavalasa
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
| | - Henrik Palmgren
- Metabolism BioScience, Cardiovascular, Renal and Metabolism, BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Hanna Ruhanen
- Helsinki University Lipidomics Unit, Helsinki Institute for Life Science, Helsinki, Finland.,Molecular and Integrative Biosciences Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Jan Boren
- Department of Molecular and Clinical Medicine/Wallenberg Laboratory, Institute of Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Marc Pilon
- Department of Chemistry and Molecular Biology, University of Gothenburg, Gothenburg, Sweden
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11
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Stastna M. Continuous flow electrophoretic separation - Recent developments and applications to biological sample analysis. Electrophoresis 2019; 41:36-55. [PMID: 31650578 DOI: 10.1002/elps.201900288] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2019] [Revised: 10/08/2019] [Accepted: 10/10/2019] [Indexed: 01/23/2023]
Abstract
Continuous flow electrophoretic separation with continuous sample loading provides the advantage of processing volumes of any sizes, as well as the benefit of a real-time monitoring and optimization of the separation process. In addition, the spatial separation of the sample enables collecting multiple separated components simultaneously and in a continuous manner. The separation is usually performed in mild buffers without organic solvents and detergents (sample biological activity is retained) and it is carried out without usage of a solid support in the separation space preventing the interaction of the sample with it (high sample recovery). The method is used for the separation of proteins/peptides in proteomic applications, and its great applicability is to the separation of the cells, cellular organelles, vesicles, membrane fragments, and DNA. This review focuses on the electrophoretic separation performed in a continuous flow and it describes various electrophoretic modes and instrumental setups. Recent developments in methodology and instrumentation, the integration with other techniques, and the application to the biological sample analysis are discussed as well.
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Affiliation(s)
- Miroslava Stastna
- Institute of Analytical Chemistry of the Czech Academy of Sciences, Brno, Czech Republic
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12
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Abstract
Peroxisomes are key metabolic organelles, which contribute to cellular lipid metabolism, e.g. the β-oxidation of fatty acids and the synthesis of myelin sheath lipids, as well as cellular redox balance. Peroxisomal dysfunction has been linked to severe metabolic disorders in man, but peroxisomes are now also recognized as protective organelles with a wider significance in human health and potential impact on a large number of globally important human diseases such as neurodegeneration, obesity, cancer, and age-related disorders. Therefore, the interest in peroxisomes and their physiological functions has significantly increased in recent years. In this review, we intend to highlight recent discoveries, advancements and trends in peroxisome research, and present an update as well as a continuation of two former review articles addressing the unsolved mysteries of this astonishing organelle. We summarize novel findings on the biological functions of peroxisomes, their biogenesis, formation, membrane dynamics and division, as well as on peroxisome-organelle contacts and cooperation. Furthermore, novel peroxisomal proteins and machineries at the peroxisomal membrane are discussed. Finally, we address recent findings on the role of peroxisomes in the brain, in neurological disorders, and in the development of cancer.
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Affiliation(s)
- Markus Islinger
- Institute of Neuroanatomy, Center for Biomedicine and Medical Technology Mannheim, Medical Faculty Manheim, University of Heidelberg, 68167, Mannheim, Germany
| | - Alfred Voelkl
- Institute for Anatomy and Cell Biology, University of Heidelberg, 69120, Heidelberg, Germany
| | - H Dariush Fahimi
- Institute for Anatomy and Cell Biology, University of Heidelberg, 69120, Heidelberg, Germany
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13
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Islinger M, Wildgruber R, Völkl A. Preparative free-flow electrophoresis, a versatile technology complementing gradient centrifugation in the isolation of highly purified cell organelles. Electrophoresis 2018; 39:2288-2299. [DOI: 10.1002/elps.201800187] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2018] [Accepted: 05/01/2018] [Indexed: 12/13/2022]
Affiliation(s)
- Markus Islinger
- Institute for Neuroanatomy, Centre for Biomedicine and Medical Technology Mannheim, Medical Faculty Mannheim; University of Heidelberg; Heidelberg Germany
| | | | - Alfred Völkl
- Department of Medical Cell Biology; Institute of Anatomy; University of Heidelberg; Heidelberg Germany
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14
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Islinger M, Manner A, Völkl A. The Craft of Peroxisome Purification-A Technical Survey Through the Decades. Subcell Biochem 2018; 89:85-122. [PMID: 30378020 DOI: 10.1007/978-981-13-2233-4_4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Purification technologies are one of the working horses in organelle proteomics studies as they guarantee the separation of organelle-specific proteins from the background contamination by other subcellular compartments. The development of methods for the separation of organelles was a major prerequisite for the initial detection and characterization of peroxisome as a discrete entity of the cell. Since then, isolated peroxisomes fractions have been used in numerous studies in order to characterize organelle-specific enzyme functions, to allocate the peroxisome-specific proteome or to unravel the organellar membrane composition. This review will give an overview of the fractionation methods used for the isolation of peroxisomes from animals, plants and fungi. In addition to "classic" centrifugation-based isolation methods, relying on the different densities of individual organelles, the review will also summarize work on alternative technologies like free-flow-electrophoresis or flow field fractionation which are based on distinct physicochemical parameters. A final chapter will further describe how different separation methods and quantitative mass spectrometry have been used in proteomics studies to assign the proteome of PO.
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Affiliation(s)
- Markus Islinger
- Institute for Neuroanatomy, Centre for Biomedicine and Medical Technology Mannheim, Medical Faculty Mannheim, University of Heidelberg, Heidelberg, Germany.
| | - Andreas Manner
- Institute for Neuroanatomy, Centre for Biomedicine and Medical Technology Mannheim, Medical Faculty Mannheim, University of Heidelberg, Heidelberg, Germany
| | - Alfred Völkl
- Department of Medical Cell Biology, Institute of Anatomy, University of Heidelberg, Heidelberg, Germany
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15
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Abstract
The current view on peroxisomes has changed dramatically from being human cell oddities to vital organelles that host several key metabolic pathways. To fulfil over 50 different enzymatic functions, human peroxisomes host either unique peroxisomal proteins or dual-localized proteins. The identification and characterization of the complete peroxisomal proteome in humans is important for diagnosis and treatment of patients with peroxisomal disorders as well as for uncovering novel peroxisomal functions and regulatory modules. Hence, here we compiled a comprehensive list of mammalian peroxisomal and peroxisome-associated proteins by curating results of several quantitative and non-quantitative proteomic studies together with entries in the UniProtKB and Compartments knowledge channel databases. Our analysis gives a holistic view on the mammalian peroxisomal proteome and brings to light potential new peroxisomal and peroxisome-associated proteins. We believe that this dataset, represents a valuable surrogate map of the human peroxisomal proteome.
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16
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He YC, Kong FZ, Fan LY, Wu JY, Liu XP, Li J, Sun Y, Zhang Q, Yang Y, Wu XJ, Xiao H, Cao CX. Preparation of intact mitochondria using free-flow isoelectric focusing with post-pH gradient sample injection for morphological, functional and proteomics studies. Anal Chim Acta 2017; 982:200-208. [DOI: 10.1016/j.aca.2017.06.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Revised: 06/10/2017] [Accepted: 06/13/2017] [Indexed: 12/31/2022]
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17
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Yofe I, Soliman K, Chuartzman SG, Morgan B, Weill U, Yifrach E, Dick TP, Cooper SJ, Ejsing CS, Schuldiner M, Zalckvar E, Thoms S. Pex35 is a regulator of peroxisome abundance. J Cell Sci 2017; 130:791-804. [PMID: 28049721 DOI: 10.1242/jcs.187914] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 11/24/2016] [Indexed: 12/12/2022] Open
Abstract
Peroxisomes are cellular organelles with vital functions in lipid, amino acid and redox metabolism. The cellular formation and dynamics of peroxisomes are governed by PEX genes; however, the regulation of peroxisome abundance is still poorly understood. Here, we use a high-content microscopy screen in Saccharomyces cerevisiae to identify new regulators of peroxisome size and abundance. Our screen led to the identification of a previously uncharacterized gene, which we term PEX35, which affects peroxisome abundance. PEX35 encodes a peroxisomal membrane protein, a remote homolog to several curvature-generating human proteins. We systematically characterized the genetic and physical interactome as well as the metabolome of mutants in PEX35, and we found that Pex35 functionally interacts with the vesicle-budding-inducer Arf1. Our results highlight the functional interaction between peroxisomes and the secretory pathway.
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Affiliation(s)
- Ido Yofe
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Kareem Soliman
- Department of Child and Adolescent Health, University Medical Center, Göttingen 37075, Germany
| | - Silvia G Chuartzman
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Bruce Morgan
- Department of Cellular Biochemistry, University of Kaiserslautern, Kaiserslautern 67653, Germany.,Division of Redox Regulation, ZMBH-DKFZ Alliance, German Cancer Research Center (DKFZ), Heidelberg 69121, Germany
| | - Uri Weill
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Eden Yifrach
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Tobias P Dick
- Division of Redox Regulation, ZMBH-DKFZ Alliance, German Cancer Research Center (DKFZ), Heidelberg 69121, Germany
| | - Sara J Cooper
- HudsonAlpha Institute for Biotechnology, Huntsville, AL 35806, USA
| | - Christer S Ejsing
- Department of Biochemistry and Molecular Biology, VILLUM Center for Bioanalytical Sciences, University of Southern Denmark, Odense 5230, Denmark
| | - Maya Schuldiner
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Einat Zalckvar
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Sven Thoms
- Department of Child and Adolescent Health, University Medical Center, Göttingen 37075, Germany
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18
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Novo P, Dell'Aica M, Jender M, Höving S, Zahedi RP, Janasek D. Integration of polycarbonate membranes in microfluidic free-flow electrophoresis. Analyst 2017; 142:4228-4239. [DOI: 10.1039/c7an01514c] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A general difficulty in the miniaturization of free-flow electrophoresis relates to the need to separate electrodes and separation bed compartments.
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Affiliation(s)
- Pedro Novo
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V
- 44227 Dortmund
- Germany
| | - Margherita Dell'Aica
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V
- 44227 Dortmund
- Germany
| | - Matthias Jender
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V
- 44227 Dortmund
- Germany
| | - Stefan Höving
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V
- 44227 Dortmund
- Germany
| | - René P. Zahedi
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V
- 44227 Dortmund
- Germany
| | - Dirk Janasek
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V
- 44227 Dortmund
- Germany
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19
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Schrader M, Costello J, Godinho LF, Islinger M. Peroxisome-mitochondria interplay and disease. J Inherit Metab Dis 2015; 38:681-702. [PMID: 25687155 DOI: 10.1007/s10545-015-9819-7] [Citation(s) in RCA: 130] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Revised: 01/21/2015] [Accepted: 01/26/2015] [Indexed: 12/16/2022]
Abstract
Peroxisomes and mitochondria are ubiquitous, highly dynamic organelles with an oxidative type of metabolism in eukaryotic cells. Over the years, substantial evidence has been provided that peroxisomes and mitochondria exhibit a close functional interplay which impacts on human health and development. The so-called "peroxisome-mitochondria connection" includes metabolic cooperation in the degradation of fatty acids, a redox-sensitive relationship, an overlap in key components of the membrane fission machineries and cooperation in anti-viral signalling and defence. Furthermore, combined peroxisome-mitochondria disorders with defects in organelle division have been revealed. In this review, we present the latest progress in the emerging field of peroxisomal and mitochondrial interplay in mammals with a particular emphasis on cooperative fatty acid β-oxidation, redox interplay, organelle dynamics, cooperation in anti-viral signalling and the resulting implications for disease.
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Affiliation(s)
- Michael Schrader
- College of Life and Environmental Sciences, Biosciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK,
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20
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Yan J, Yang CZ, Zhang Q, Liu XP, Kong FZ, Cao CX, Jin XQ. Experimental study on the optimization of general conditions for a free-flow electrophoresis device with a thermoelectric cooler†. J Sep Sci 2014; 37:3555-63. [DOI: 10.1002/jssc.201400770] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Revised: 08/22/2014] [Accepted: 09/04/2014] [Indexed: 11/10/2022]
Affiliation(s)
- Jian Yan
- Key State Laboratory of Microbial Metabolism; School of Life Science and Biotechnology; Shanghai Jiao Tong University; Shanghai China
- Institute of Refrigeration and Cryogenics; School of Mechanical Engineering; Shanghai Jiao Tong University; Shanghai China
| | - Cheng-Zhang Yang
- Key State Laboratory of Microbial Metabolism; School of Life Science and Biotechnology; Shanghai Jiao Tong University; Shanghai China
| | - Qiang Zhang
- Key State Laboratory of Microbial Metabolism; School of Life Science and Biotechnology; Shanghai Jiao Tong University; Shanghai China
| | - Xiao-Ping Liu
- Key State Laboratory of Microbial Metabolism; School of Life Science and Biotechnology; Shanghai Jiao Tong University; Shanghai China
| | - Fan-Zhi Kong
- Key State Laboratory of Microbial Metabolism; School of Life Science and Biotechnology; Shanghai Jiao Tong University; Shanghai China
| | - Cheng-Xi Cao
- Key State Laboratory of Microbial Metabolism; School of Life Science and Biotechnology; Shanghai Jiao Tong University; Shanghai China
| | - Xin-Qiao Jin
- Institute of Refrigeration and Cryogenics; School of Mechanical Engineering; Shanghai Jiao Tong University; Shanghai China
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21
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Yang CZ, Yan J, Zhang Q, Guo CG, Kong FZ, Cao CX, Fan LY, Jin XQ. Negative-pressure-induced collector for a self-balance free-flow electrophoresis device. J Sep Sci 2014; 37:1359-63. [PMID: 24648284 DOI: 10.1002/jssc.201400007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Revised: 03/12/2014] [Accepted: 03/13/2014] [Indexed: 11/10/2022]
Abstract
Uneven flow in free-flow electrophoresis (FFE) with a gravity-induced fraction collector caused by air bubbles in outlets and/or imbalance of the surface tension of collecting tubes would result in a poor separation. To solve these issues, this work describes a novel collector for FFE. The collector is composed of a self-balance unit, multisoft pipe flow controller, fraction collector, and vacuum pump. A negative pressure induced continuous air flow rapidly flowed through the self-balance unit, taking the background electrolyte and samples into the fraction collector. The developed collector has the following advantages: (i) supplying a stable and harmonious hydrodynamic environment in the separation chamber for FFE separation, (ii) effectively preventing background electrolyte and sample flow-back at the outlet of the chamber and improving the resolution, (iii) increasing the preparative scale of the separation, and (iv) simplifying the operation. In addition, the cost of the FFE device was reduced without using a multichannel peristaltic pump for sample collection. Finally, comparative FFE experiments on dyes, proteins, and cells were carried out. It is evident that the new developed collector could overcome the problems inherent in the previous gravity-induced self-balance collector.
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Affiliation(s)
- Cheng-Zhang Yang
- Laboratory of Analytical Biochemistry and Bioseparation, Key State Laboratory of Microbial Metabolism, School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
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22
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Hunt MC, Tillander V, Alexson SEH. Regulation of peroxisomal lipid metabolism: the role of acyl-CoA and coenzyme A metabolizing enzymes. Biochimie 2014; 98:45-55. [PMID: 24389458 DOI: 10.1016/j.biochi.2013.12.018] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2013] [Accepted: 12/19/2013] [Indexed: 12/11/2022]
Abstract
Peroxisomes are nearly ubiquitous organelles involved in a number of metabolic pathways that vary between organisms and tissues. A common metabolic function in mammals is the partial degradation of various (di)carboxylic acids via α- and β-oxidation. While only a small number of enzymes catalyze the reactions of β-oxidation, numerous auxiliary enzymes have been identified to be involved in uptake of fatty acids and cofactors required for β-oxidation, regulation of β-oxidation and transport of metabolites across the membrane. These proteins include membrane transporters/channels, acyl-CoA thioesterases, acyl-CoA:amino acid N-acyltransferases, carnitine acyltransferases and nudix hydrolases. Here we review the current view of the role of these auxiliary enzymes in peroxisomal lipid metabolism and propose that they function in concert to provide a means to regulate fatty acid metabolism and transport of products across the peroxisomal membrane.
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Affiliation(s)
- Mary C Hunt
- Dublin Institute of Technology, College of Sciences & Health, School of Biological Sciences, Kevin Street, Dublin 8, Ireland.
| | - Veronika Tillander
- Karolinska Institutet, Department of Laboratory Medicine, Division of Clinical Chemistry, Karolinska University Hospital, SE 141 86, Stockholm, Sweden
| | - Stefan E H Alexson
- Karolinska Institutet, Department of Laboratory Medicine, Division of Clinical Chemistry, Karolinska University Hospital, SE 141 86, Stockholm, Sweden
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23
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Parsons HT, Fernández-Niño SMG, Heazlewood JL. Separation of the plant Golgi apparatus and endoplasmic reticulum by free-flow electrophoresis. Methods Mol Biol 2014; 1072:527-539. [PMID: 24136544 DOI: 10.1007/978-1-62703-631-3_35] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Free-flow electrophoresis (FFE) is a technique for separation of proteins, peptides, organelles, and cells. With zone electrophoresis (ZE-FFE), organelles are separated according to surface charge. The plant Golgi and endoplasmic reticulum (ER) are similar in density and are therefore separated with difficulty using standard techniques such as density centrifugation. Purification of the ER and Golgi apparatus permits a biochemical and proteomic characterization which can reveal the division of processes between these compartments. Here we describe complete separation between the ER and more negatively charged Golgi compartments using ZE-FFE. We also describe techniques for assigning proteins to partially separated ER and the less negatively charged Golgi compartments.
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Affiliation(s)
- Harriet T Parsons
- Joint BioEnergy Institute and Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
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24
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Yan J, Guo CG, Liu XP, Kong FZ, Shen QY, Yang CZ, Li J, Cao CX, Jin XQ. A simple and highly stable free-flow electrophoresis device with thermoelectric cooling system. J Chromatogr A 2013; 1321:119-26. [DOI: 10.1016/j.chroma.2013.10.058] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Revised: 10/01/2013] [Accepted: 10/18/2013] [Indexed: 11/26/2022]
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25
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Wildgruber R, Weber G, Wise P, Grimm D, Bauer J. Free-flow electrophoresis in proteome sample preparation. Proteomics 2013; 14:629-36. [PMID: 24123730 DOI: 10.1002/pmic.201300253] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2013] [Revised: 08/07/2013] [Accepted: 08/23/2013] [Indexed: 02/01/2023]
Abstract
An aim of proteome research is to identify the entire complement of proteins expressed in defined cell types of humans, animals, plants, and microorganisms. The approach requires searching for low abundant or even rarely expressed proteins in many cell types, as well as the determination of the protein expression levels in subcellular compartments and organelles. In recent years, rather powerful MS technologies have been developed. At this stage of MS device development, it is of highest interest to purify intact cell types or isolate subcellular compartments, where the proteins of interest are originating from, which determine the final composition of a peptide mixture. Free-flow electrophoresis proved to be useful to prepare meaningful peptide mixtures because of its improved capabilities in particle electrophoresis and the enhanced resolution in protein separation. Sample preparation by free-flow electrophoresis mediated particle separation was preferentially performed for purification of either organelles and their subspecies or major protein complexes. Especially, the introduction of isotachophoresis and interval zone electrophoresis improved the purity of the gained analytes of interest. In addition, free-flow IEF proved to be helpful, when proteins of low solubility, obtained, e.g. from cell membranes, were investigated.
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26
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Satori CP, Henderson MM, Krautkramer EA, Kostal V, Distefano MM, Arriaga EA. Bioanalysis of eukaryotic organelles. Chem Rev 2013; 113:2733-811. [PMID: 23570618 PMCID: PMC3676536 DOI: 10.1021/cr300354g] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Chad P. Satori
- Department of Chemistry, University of Minnesota, Twin Cities, Minneapolis, MN, USA, 55455
| | - Michelle M. Henderson
- Department of Chemistry, University of Minnesota, Twin Cities, Minneapolis, MN, USA, 55455
| | - Elyse A. Krautkramer
- Department of Chemistry, University of Minnesota, Twin Cities, Minneapolis, MN, USA, 55455
| | - Vratislav Kostal
- Tescan, Libusina trida 21, Brno, 623 00, Czech Republic
- Institute of Analytical Chemistry ASCR, Veveri 97, Brno, 602 00, Czech Republic
| | - Mark M. Distefano
- Department of Chemistry, University of Minnesota, Twin Cities, Minneapolis, MN, USA, 55455
| | - Edgar A. Arriaga
- Department of Chemistry, University of Minnesota, Twin Cities, Minneapolis, MN, USA, 55455
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27
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Schrader M, Grille S, Fahimi HD, Islinger M. Peroxisome interactions and cross-talk with other subcellular compartments in animal cells. Subcell Biochem 2013; 69:1-22. [PMID: 23821140 DOI: 10.1007/978-94-007-6889-5_1] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Peroxisomes are remarkably plastic and dynamic organelles, which fulfil important functions in hydrogen peroxide and lipid metabolism rendering them essential for human health and development. Despite great advances in the identification and characterization of essential components and molecular mechanisms associated with the biogenesis and function of peroxisomes, our understanding of how peroxisomes are incorporated into metabolic pathways and cellular communication networks is just beginning to emerge. Here we address the interaction of peroxisomes with other subcellular compartments including the relationship with the endoplasmic reticulum, the peroxisome-mitochondria connection and the association with lipid droplets. We highlight metabolic cooperations and potential cross-talk and summarize recent findings on peroxisome-peroxisome interactions and the interaction of peroxisomes with microtubules in mammalian cells.
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Affiliation(s)
- Michael Schrader
- College of Life and Environmental Sciences, Biosciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK,
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28
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Assessing heterogeneity of peroxisomes: isolation of two subpopulations from rat liver. METHODS IN MOLECULAR BIOLOGY (CLIFTON, N.J.) 2012; 909:83-96. [PMID: 22903710 DOI: 10.1007/978-1-61779-959-4_6] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Peroxisomes exhibit a heterogeneous morphological appearance in rat liver tissue. In this respect, the isolation and subsequent biochemical characterization of peroxisome species from different subcellular prefractions should help to solve the question of whether peroxisomes indeed diverge into functionally specialized subgroups in one tissue. As a means to address this question, we provide a detailed separation protocol for the isolation of peroxisomes from both the light (LM-Po) and the heavy (HM-Po) mitochondrial prefraction for their subsequent comparative analysis. Both isolation strategies rely on centrifugation in individually adapted Optiprep gradients. In case of the heavy mitochondrial fraction, free flow electrophoresis is appended as an additional separation step to yield peroxisomes of sufficient purity. In view of their morphology, peroxisomes isolated from both fractions are surrounded by a continuous single membrane and contain a gray-opaque inner matrix. However, beyond this overall similar appearance, HM-Po exhibit a smaller average diameter, float at lower density, and show a more negative average membrane charge when compared to LM-Po.
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29
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Satori CP, Kostal V, Arriaga EA. Review on recent advances in the analysis of isolated organelles. Anal Chim Acta 2012; 753:8-18. [PMID: 23107131 PMCID: PMC3484375 DOI: 10.1016/j.aca.2012.09.041] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Revised: 09/22/2012] [Accepted: 09/24/2012] [Indexed: 10/27/2022]
Abstract
The analysis of isolated organelles is one of the pillars of modern bioanalytical chemistry. This review describes recent developments on the isolation and characterization of isolated organelles both from living organisms and cell cultures. Salient reports on methods to release organelles focused on reproducibility and yield, membrane isolation, and integrated devices for organelle release. New developments on organelle fractionation after their isolation were on the topics of centrifugation, immunocapture, free flow electrophoresis, flow field-flow fractionation, fluorescence activated organelle sorting, laser capture microdissection, and dielectrophoresis. New concepts on characterization of isolated organelles included atomic force microscopy, optical tweezers combined with Raman spectroscopy, organelle sensors, flow cytometry, capillary electrophoresis, and microfluidic devices.
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Affiliation(s)
- Chad P Satori
- Department of Chemistry, University of Minnesota, Minneapolis, MN 55455, USA
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30
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Pang B, Shao J, Zhang J, Geng JZ, Fan LY, Cao CX, Hou JL. Enhancing separation of histidine from amino acids via free-flow affinity electrophoresis with gravity-induced uniform hydrodynamic flow. Electrophoresis 2012; 33:856-65. [DOI: 10.1002/elps.201100494] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Bo Pang
- Laboratory of Bioseparation and Analytical Biochemistry; State Key Laboratory of Microbial Metabolism; School of Life Science and Biotechnology; Shanghai Jiao Tong University; Shanghai; China
| | - Jing Shao
- Laboratory of Bioseparation and Analytical Biochemistry; State Key Laboratory of Microbial Metabolism; School of Life Science and Biotechnology; Shanghai Jiao Tong University; Shanghai; China
| | - Jie Zhang
- Laboratory of Bioseparation and Analytical Biochemistry; State Key Laboratory of Microbial Metabolism; School of Life Science and Biotechnology; Shanghai Jiao Tong University; Shanghai; China
| | - Jia-Zhen Geng
- Laboratory of Bioseparation and Analytical Biochemistry; State Key Laboratory of Microbial Metabolism; School of Life Science and Biotechnology; Shanghai Jiao Tong University; Shanghai; China
| | - Liu-Yin Fan
- Laboratory of Bioseparation and Analytical Biochemistry; State Key Laboratory of Microbial Metabolism; School of Life Science and Biotechnology; Shanghai Jiao Tong University; Shanghai; China
| | - Cheng-Xi Cao
- Laboratory of Bioseparation and Analytical Biochemistry; State Key Laboratory of Microbial Metabolism; School of Life Science and Biotechnology; Shanghai Jiao Tong University; Shanghai; China
| | - Jing-Li Hou
- Instrumental Analysis Center; Shanghai Jiao Tong University; Shanghai; China
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31
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Watkins PA, Ellis JM. Peroxisomal acyl-CoA synthetases. Biochim Biophys Acta Mol Basis Dis 2012; 1822:1411-20. [PMID: 22366061 DOI: 10.1016/j.bbadis.2012.02.010] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Revised: 01/12/2012] [Accepted: 02/10/2012] [Indexed: 01/26/2023]
Abstract
Peroxisomes carry out many essential lipid metabolic functions. Nearly all of these functions require that an acyl group-either a fatty acid or the acyl side chain of a steroid derivative-be thioesterified to coenzyme A (CoA) for subsequent reactions to proceed. This thioesterification, or "activation", reaction, catalyzed by enzymes belonging to the acyl-CoA synthetase family, is thus central to cellular lipid metabolism. However, despite our rather thorough understanding of peroxisomal metabolic pathways, surprisingly little is known about the specific peroxisomal acyl-CoA synthetases that participate in these pathways. Of the 26 acyl-CoA synthetases encoded by the human and mouse genomes, only a few have been reported to be peroxisomal, including ACSL4, SLC27A2, and SLC27A4. In this review, we briefly describe the primary peroxisomal lipid metabolic pathways in which fatty acyl-CoAs participate. Then, we examine the evidence for presence and functions of acyl-CoA synthetases in peroxisomes, much of which was obtained before the existence of multiple acyl-CoA synthetase isoenzymes was known. Finally, we discuss the role(s) of peroxisome-specific acyl-CoA synthetase isoforms in lipid metabolism.
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Abstract
Micro free flow electrophoresis (micro-FFE) is a continuous micro-separation or preparation technique, which has been applied in the analysis of biomolecules, such as cells, sub cell organics and proteins. In this review, the recent progresses in micro FFE are summarized, with emphasis on the design of microchips, the separation modes and the applications of micro-FFE. Furthermore, the further developments of micro-FFE are prospected.
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Affiliation(s)
- Pingli Wang
- National Chromatographic R. & A. Center, Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
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33
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Reumann S. Toward a definition of the complete proteome of plant peroxisomes: Where experimental proteomics must be complemented by bioinformatics. Proteomics 2011; 11:1764-79. [PMID: 21472859 DOI: 10.1002/pmic.201000681] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2010] [Revised: 02/06/2011] [Accepted: 02/11/2011] [Indexed: 12/23/2022]
Abstract
In the past few years, proteome analysis of Arabidopsis peroxisomes has been established by the complementary efforts of four research groups and has emerged as the major unbiased approach to identify new peroxisomal proteins on a large scale. Collectively, more than 100 new candidate proteins from plant peroxisomes have been identified, including long-awaited low-abundance proteins. More than 50 proteins have been validated as peroxisome targeted, nearly doubling the number of established plant peroxisomal proteins. Sequence homologies of the new proteins predict unexpected enzyme activities, novel metabolic pathways and unknown non-metabolic peroxisome functions. Despite this remarkable success, proteome analyses of plant peroxisomes remain highly material intensive and require major preparative efforts. Characterization of the membrane proteome or post-translational protein modifications poses major technical challenges. New strategies, including quantitative mass spectrometry methods, need to be applied to allow further identifications of plant peroxisomal proteins, such as of stress-inducible proteins. In the long process of defining the complete proteome of plant peroxisomes, the prediction of peroxisome-targeted proteins from plant genome sequences emerges as an essential complementary approach to identify additional peroxisomal proteins that are, for instance, specific to peroxisome variants from minor tissues and organs or to abiotically stressed model and crop plants.
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Affiliation(s)
- Sigrun Reumann
- Centre for Organelle Research, University of Stavanger, Stavanger, Norway.
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34
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Ly L, Wasinger VC. Protein and peptide fractionation, enrichment and depletion: Tools for the complex proteome. Proteomics 2011; 11:513-34. [DOI: 10.1002/pmic.201000394] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Revised: 10/03/2010] [Accepted: 10/18/2010] [Indexed: 12/28/2022]
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35
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Raimondo F, Morosi L, Chinello C, Magni F, Pitto M. Advances in membranous vesicle and exosome proteomics improving biological understanding and biomarker discovery. Proteomics 2011; 11:709-20. [PMID: 21241021 DOI: 10.1002/pmic.201000422] [Citation(s) in RCA: 237] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2010] [Revised: 09/16/2010] [Accepted: 10/20/2010] [Indexed: 12/12/2022]
Abstract
Exosomes are membranous vesicles released by cells in extracellular fluids: they have been found and analyzed in blood, urine, amniotic fluid, breast milk, seminal fluid, saliva and malignant effusions, besides conditioned media from different cell lines. Several recent papers show that exosome proteomes of different origin include both a common set of membrane and cytosolic proteins, and specific subsets of proteins, likely correlated to cell-type associated functions. This is particularly interesting in relation to their possible involvement in human diseases. The knowledge of exosome proteomics can help not only in understanding their biological roles but also in supplying new biomarkers to be searched for in patients' fluids. This review offers an overview of technical and analytical issues in exosome proteomics, and it highlights the significance of proteomic studies in terms of biological and clinical usefulness.
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Affiliation(s)
- Francesca Raimondo
- Department of Experimental Medicine, University of Milano-Bicocca, Monza, Italy
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36
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Lee YH, Tan HT, Chung MCM. Subcellular fractionation methods and strategies for proteomics. Proteomics 2010; 10:3935-56. [DOI: 10.1002/pmic.201000289] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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37
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Wang P, Zhang L, Shan Y, Cong Y, Liang Y, Han B, Liang Z, Zhang Y. Protein separation using free-flow electrophoresis microchip etched in a single step. J Sep Sci 2010; 33:2039-44. [DOI: 10.1002/jssc.201000162] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Islinger M, Eckerskorn C, Völkl A. Free-flow electrophoresis in the proteomic era: A technique in flux. Electrophoresis 2010; 31:1754-63. [DOI: 10.1002/elps.200900771] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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39
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Islinger M, Cardoso MJR, Schrader M. Be different--the diversity of peroxisomes in the animal kingdom. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2010; 1803:881-97. [PMID: 20347886 DOI: 10.1016/j.bbamcr.2010.03.013] [Citation(s) in RCA: 76] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2010] [Revised: 03/15/2010] [Accepted: 03/18/2010] [Indexed: 10/19/2022]
Abstract
Peroxisomes represent so-called "multipurpose organelles" as they contribute to various anabolic as well as catabolic pathways. Thus, with respect to the physiological specialization of an individual organ or animal species, peroxisomes exhibit a functional diversity, which is documented by significant variations in their proteome. These differences are usually regarded as an adaptational response to the nutritional and environmental life conditions of a specific organism. Thus, human peroxisomes can be regarded as an in part physiologically unique organellar entity fulfilling metabolic functions that differ from our animal model systems. In line with this, a profound understanding on how peroxisomes acquired functional heterogeneity in terms of an evolutionary and mechanistic background is required. This review summarizes our current knowledge on the heterogeneity of peroxisomal physiology, providing insights into the genetic and cell biological mechanisms, which lead to the differential localization or expression of peroxisomal proteins and further gives an overview on peroxisomal biochemical pathways, which are specialized in different animal species and organs. Moreover, it addresses the impact of proteome studies on our understanding of differential peroxisome function describing the utility of mass spectrometry and computer-assisted algorithms to identify peroxisomal target sequences for the detection of new organ- or species-specific peroxisomal proteins.
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Affiliation(s)
- M Islinger
- Department of Anatomy and Cell Biology, Ruprecht-Karls University, 69120 Heidelberg, Germany
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