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Briand-Mésange F, Gennero I, Salles J, Trudel S, Dahan L, Ausseil J, Payrastre B, Salles JP, Chap H. From Classical to Alternative Pathways of 2-Arachidonoylglycerol Synthesis: AlterAGs at the Crossroad of Endocannabinoid and Lysophospholipid Signaling. Molecules 2024; 29:3694. [PMID: 39125098 PMCID: PMC11314389 DOI: 10.3390/molecules29153694] [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: 06/21/2024] [Revised: 07/27/2024] [Accepted: 08/02/2024] [Indexed: 08/12/2024] Open
Abstract
2-arachidonoylglycerol (2-AG) is the most abundant endocannabinoid (EC), acting as a full agonist at both CB1 and CB2 cannabinoid receptors. It is synthesized on demand in postsynaptic membranes through the sequential action of phosphoinositide-specific phospholipase Cβ1 (PLCβ1) and diacylglycerol lipase α (DAGLα), contributing to retrograde signaling upon interaction with presynaptic CB1. However, 2-AG production might also involve various combinations of PLC and DAGL isoforms, as well as additional intracellular pathways implying other enzymes and substrates. Three other alternative pathways of 2-AG synthesis rest on the extracellular cleavage of 2-arachidonoyl-lysophospholipids by three different hydrolases: glycerophosphodiesterase 3 (GDE3), lipid phosphate phosphatases (LPPs), and two members of ecto-nucleotide pyrophosphatase/phosphodiesterases (ENPP6-7). We propose the names of AlterAG-1, -2, and -3 for three pathways sharing an ectocellular localization, allowing them to convert extracellular lysophospholipid mediators into 2-AG, thus inducing typical signaling switches between various G-protein-coupled receptors (GPCRs). This implies the critical importance of the regioisomerism of both lysophospholipid (LPLs) and 2-AG, which is the object of deep analysis within this review. The precise functional roles of AlterAGs are still poorly understood and will require gene invalidation approaches, knowing that both 2-AG and its related lysophospholipids are involved in numerous aspects of physiology and pathology, including cancer, inflammation, immune defenses, obesity, bone development, neurodegeneration, or psychiatric disorders.
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Affiliation(s)
- Fabienne Briand-Mésange
- Infinity-Toulouse Institute for Infectious and Inflammatory Diseases, University of Toulouse, INSERM, CNRS, Paul Sabatier University, 31059 Toulouse, France; (F.B.-M.); (I.G.); (J.S.); (S.T.); (J.A.); (J.-P.S.)
| | - Isabelle Gennero
- Infinity-Toulouse Institute for Infectious and Inflammatory Diseases, University of Toulouse, INSERM, CNRS, Paul Sabatier University, 31059 Toulouse, France; (F.B.-M.); (I.G.); (J.S.); (S.T.); (J.A.); (J.-P.S.)
- Centre Hospitalier Universitaire de Toulouse, Service de Biochimie, Institut Fédératif de Biologie, 31059 Toulouse, France
| | - Juliette Salles
- Infinity-Toulouse Institute for Infectious and Inflammatory Diseases, University of Toulouse, INSERM, CNRS, Paul Sabatier University, 31059 Toulouse, France; (F.B.-M.); (I.G.); (J.S.); (S.T.); (J.A.); (J.-P.S.)
- Centre Hospitalier Universitaire de Toulouse, Service de Psychiatrie D’urgences, de Crise et de Liaison, Institut des Handicaps Neurologiques, Psychiatriques et Sensoriels, 31059 Toulouse, France
| | - Stéphanie Trudel
- Infinity-Toulouse Institute for Infectious and Inflammatory Diseases, University of Toulouse, INSERM, CNRS, Paul Sabatier University, 31059 Toulouse, France; (F.B.-M.); (I.G.); (J.S.); (S.T.); (J.A.); (J.-P.S.)
- Centre Hospitalier Universitaire de Toulouse, Service de Biochimie, Institut Fédératif de Biologie, 31059 Toulouse, France
| | - Lionel Dahan
- Centre de Recherches sur la Cognition Animale (CRCA), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, 31062 Toulouse, France;
| | - Jérôme Ausseil
- Infinity-Toulouse Institute for Infectious and Inflammatory Diseases, University of Toulouse, INSERM, CNRS, Paul Sabatier University, 31059 Toulouse, France; (F.B.-M.); (I.G.); (J.S.); (S.T.); (J.A.); (J.-P.S.)
- Centre Hospitalier Universitaire de Toulouse, Service de Biochimie, Institut Fédératif de Biologie, 31059 Toulouse, France
| | - Bernard Payrastre
- I2MC-Institute of Metabolic and Cardiovascular Diseases, INSERM UMR1297 and University of Toulouse III, 31400 Toulouse, France;
- Centre Hospitalier Universitaire de Toulouse, Laboratoire d’Hématologie, 31400 Toulouse, France
| | - Jean-Pierre Salles
- Infinity-Toulouse Institute for Infectious and Inflammatory Diseases, University of Toulouse, INSERM, CNRS, Paul Sabatier University, 31059 Toulouse, France; (F.B.-M.); (I.G.); (J.S.); (S.T.); (J.A.); (J.-P.S.)
- Centre Hospitalier Universitaire de Toulouse, Unité d’Endocrinologie et Maladies Osseuses, Hôpital des Enfants, 31059 Toulouse, France
| | - Hugues Chap
- Infinity-Toulouse Institute for Infectious and Inflammatory Diseases, University of Toulouse, INSERM, CNRS, Paul Sabatier University, 31059 Toulouse, France; (F.B.-M.); (I.G.); (J.S.); (S.T.); (J.A.); (J.-P.S.)
- Académie des Sciences, Inscriptions et Belles Lettres de Toulouse, Hôtel d’Assézat, 31000 Toulouse, France
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2
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Venkatraman K, Budin I. Cardiolipin remodeling maintains the inner mitochondrial membrane in cells with saturated lipidomes. J Lipid Res 2024; 65:100601. [PMID: 39038656 PMCID: PMC11381790 DOI: 10.1016/j.jlr.2024.100601] [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: 05/28/2024] [Revised: 07/14/2024] [Accepted: 07/16/2024] [Indexed: 07/24/2024] Open
Abstract
Cardiolipin (CL) is a unique, four-chain phospholipid synthesized in the inner mitochondrial membrane (IMM). The acyl chain composition of CL is regulated through a remodeling pathway, whose loss causes mitochondrial dysfunction in Barth syndrome (BTHS). Yeast has been used extensively as a model system to characterize CL metabolism, but mutants lacking its two remodeling enzymes, Cld1p and Taz1p, exhibit mild structural and respiratory phenotypes compared to mammalian cells. Here, we show an essential role for CL remodeling in the structure and function of the IMM in yeast grown under reduced oxygenation. Microaerobic fermentation, which mimics natural yeast environments, caused the accumulation of saturated fatty acids and, under these conditions, remodeling mutants showed a loss of IMM ultrastructure. We extended this observation to HEK293 cells, where phospholipase A2 inhibition by Bromoenol lactone resulted in respiratory dysfunction and cristae loss upon mild treatment with exogenous saturated fatty acids. In microaerobic yeast, remodeling mutants accumulated unremodeled, saturated CL, but also displayed reduced total CL levels, highlighting the interplay between saturation and CL biosynthesis and/or breakdown. We identified the mitochondrial phospholipase A1 Ddl1p as a regulator of CL levels, and those of its precursors phosphatidylglycerol and phosphatidic acid, under these conditions. Loss of Ddl1p partially rescued IMM structure in cells unable to initiate CL remodeling and had differing lipidomic effects depending on oxygenation. These results introduce a revised yeast model for investigating CL remodeling and suggest that its structural functions are dependent on the overall lipid environment in the mitochondrion.
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Affiliation(s)
- Kailash Venkatraman
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA, USA
| | - Itay Budin
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA, USA.
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3
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Akefe IO, Saber SH, Matthews B, Venkatesh BG, Gormal RS, Blackmore DG, Alexander S, Sieriecki E, Gambin Y, Bertran-Gonzalez J, Vitale N, Humeau Y, Gaudin A, Ellis SA, Michaels AA, Xue M, Cravatt B, Joensuu M, Wallis TP, Meunier FA. The DDHD2-STXBP1 interaction mediates long-term memory via generation of saturated free fatty acids. EMBO J 2024; 43:533-567. [PMID: 38316990 PMCID: PMC10897203 DOI: 10.1038/s44318-024-00030-7] [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: 05/11/2023] [Revised: 12/06/2023] [Accepted: 12/14/2023] [Indexed: 02/07/2024] Open
Abstract
The phospholipid and free fatty acid (FFA) composition of neuronal membranes plays a crucial role in learning and memory, but the mechanisms through which neuronal activity affects the brain's lipid landscape remain largely unexplored. The levels of saturated FFAs, particularly of myristic acid (C14:0), strongly increase during neuronal stimulation and memory acquisition, suggesting the involvement of phospholipase A1 (PLA1) activity in synaptic plasticity. Here, we show that genetic ablation of the PLA1 isoform DDHD2 in mice dramatically reduces saturated FFA responses to memory acquisition across the brain. Furthermore, DDHD2 loss also decreases memory performance in reward-based learning and spatial memory models prior to the development of neuromuscular deficits that mirror human spastic paraplegia. Via pulldown-mass spectrometry analyses, we find that DDHD2 binds to the key synaptic protein STXBP1. Using STXBP1/2 knockout neurosecretory cells and a haploinsufficient STXBP1+/- mouse model of human early infantile encephalopathy associated with intellectual disability and motor dysfunction, we show that STXBP1 controls targeting of DDHD2 to the plasma membrane and generation of saturated FFAs in the brain. These findings suggest key roles for DDHD2 and STXBP1 in lipid metabolism and in the processes of synaptic plasticity, learning, and memory.
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Affiliation(s)
- Isaac O Akefe
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
- Academy for Medical Education, Medical School, The University of Queensland, 288 Herston Road, 4006, Brisbane, QLD, Australia
| | - Saber H Saber
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, St Lucia, QLD, 4072, Australia
| | - Benjamin Matthews
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Bharat G Venkatesh
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Rachel S Gormal
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Daniel G Blackmore
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Suzy Alexander
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Emma Sieriecki
- School of Medical Science, University of New South Wales, Randwick, NSW, 2052, Australia
- EMBL Australia, Single Molecule Node, University of New South Wales, Sydney, 2052, Australia
| | - Yann Gambin
- School of Medical Science, University of New South Wales, Randwick, NSW, 2052, Australia
- EMBL Australia, Single Molecule Node, University of New South Wales, Sydney, 2052, Australia
| | | | - Nicolas Vitale
- Institut des Neurosciences Cellulaires et Intégratives, UPR-3212 CNRS - Université de Strasbourg, Strasbourg, France
| | - Yann Humeau
- Interdisciplinary Institute for Neuroscience, CNRS UMR 5297, Université de Bordeaux, Bordeaux, France
| | - Arnaud Gaudin
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Sevannah A Ellis
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Alysee A Michaels
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX, USA
| | - Mingshan Xue
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
- The Cain Foundation Laboratories, Jan and Dan Duncan Neurological Research Institute at Texas Children's Hospital, Houston, TX, USA
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, USA
| | - Benjamin Cravatt
- The Department of Chemistry and The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - Merja Joensuu
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia.
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, St Lucia, QLD, 4072, Australia.
| | - Tristan P Wallis
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia.
| | - Frédéric A Meunier
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, 4072, Australia.
- The School of Biomedical Sciences, The University of Queensland, St Lucia, QLD, 4072, Australia.
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Narayanasamy R, Usharani D, Rajasekharan R. Elucidating the functional role of human ABHD16B lipase in regulating triacylglycerol mobilization and membrane lipid synthesis in Saccharomyces cerevisiae. Chem Phys Lipids 2024; 258:105353. [PMID: 37944658 DOI: 10.1016/j.chemphyslip.2023.105353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2023] [Accepted: 11/06/2023] [Indexed: 11/12/2023]
Abstract
Lipids are essential biological macromolecules that play a pivotal role in various physiological processes and cellular homeostasis. ABHD16B, a member of the α/β-hydrolase domain (ABHD) superfamily protein, has emerged as a potential key regulator in lipid metabolism. However, the precise role of human ABHD16B in lipid metabolism remains unclear. In this study, we reported the overexpression of ABHD16B in Saccharomyces cerevisiae to determine its physiological relevance in lipid metabolism. Through in vivo [14C]acetate labeling experiments, we observed that overexpression of ABHD16B causes a decrease in cellular triacylglycerol (TAG) levels and a concurrent increase in phospholipid synthesis in wild-type cells. Mass spectrometry (LC-MS/MS) analysis further corroborated these findings, showing a significant decrease in TAGs with a carbon chain length of 48 and an increase in major phospholipid species, specifically 34:2, upon overexpression of ABHD16B. Confocal microscopy analysis revealed a reduction in the number of lipid droplets in strains overexpressing ABHD16B, consistent with the observed decrease in neutral lipids. Additionally, qRT-PCR analysis indicated a high phospholipid synthetic activity of ABHD16B and a potential decrease in TAG levels in wild-type yeast, possibly due to upregulation of endogenous TAG hydrolytic enzymes, as confirmed using 3tglsΔ mutant strain. Furthermore, GC-MS analysis revealed significant modifications in fatty acid composition upon ABHD16B overexpression. Collectively, our results underscore the influence of ABHD16B overexpression on TAG levels, phospholipid synthesis, lipid droplet dynamics, and fatty acid composition. These findings reveal a complex interplay between TAG hydrolysis and phospholipid synthesis, highlighting the critical involvement of ABHD16B in lipid homeostasis and providing further insights into its regulatory function in cellular lipid metabolism.
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Affiliation(s)
- Raja Narayanasamy
- Department of Food Safety and Analytical Quality Control Laboratory, CSIR-Central Food Technological Research Institute (CFTRI), Mysore, Karnataka 570020, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India
| | - Dandamudi Usharani
- Department of Food Safety and Analytical Quality Control Laboratory, CSIR-Central Food Technological Research Institute (CFTRI), Mysore, Karnataka 570020, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad 201002, India.
| | - Ram Rajasekharan
- Department of Microbiology, School of Life Sciences, Central University of Tamil Nadu, Neelakudi, Thiruvarur 610005, India.
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Hofer P, Grabner GF, König M, Xie H, Bulfon D, Ludwig AE, Wolinski H, Zimmermann R, Zechner R, Heier C. Cooperative lipolytic control of neuronal triacylglycerol by spastic paraplegia-associated enzyme DDHD2 and ATGL. J Lipid Res 2023; 64:100457. [PMID: 37832604 PMCID: PMC10665947 DOI: 10.1016/j.jlr.2023.100457] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 10/01/2023] [Accepted: 10/04/2023] [Indexed: 10/15/2023] Open
Abstract
Intracellular lipolysis-the enzymatic breakdown of lipid droplet-associated triacylglycerol (TAG)-depends on the cooperative action of several hydrolytic enzymes and regulatory proteins, together designated as lipolysome. Adipose triglyceride lipase (ATGL) acts as a major cellular TAG hydrolase and core effector of the lipolysome in many peripheral tissues. Neurons initiate lipolysis independently of ATGL via DDHD domain-containing 2 (DDHD2), a multifunctional lipid hydrolase whose dysfunction causes neuronal TAG deposition and hereditary spastic paraplegia. Whether and how DDHD2 cooperates with other lipolytic enzymes is currently unknown. In this study, we further investigated the enzymatic properties and functions of DDHD2 in neuroblastoma cells and primary neurons. We found that DDHD2 hydrolyzes multiple acylglycerols in vitro and substantially contributes to neutral lipid hydrolase activities of neuroblastoma cells and brain tissue. Substrate promiscuity of DDHD2 allowed its engagement at different steps of the lipolytic cascade: In neuroblastoma cells, DDHD2 functioned exclusively downstream of ATGL in the hydrolysis of sn-1,3-diacylglycerol (DAG) isomers but was dispensable for TAG hydrolysis and lipid droplet homeostasis. In primary cortical neurons, DDHD2 exhibited lipolytic control over both, DAG and TAG, and complemented ATGL-dependent TAG hydrolysis. We conclude that neuronal cells use noncanonical configurations of the lipolysome and engage DDHD2 as dual TAG/DAG hydrolase in cooperation with ATGL.
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Affiliation(s)
- Peter Hofer
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Gernot F Grabner
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Mario König
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Hao Xie
- Institute of Molecular Biosciences, University of Graz, Graz, Austria; State Key Laboratory of Natural Medicines, Key Laboratory of Drug Metabolism and Pharmacokinetics, China Pharmaceutical University, Nanjing, China
| | - Dominik Bulfon
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Anton E Ludwig
- Institute of Molecular Biosciences, University of Graz, Graz, Austria
| | - Heimo Wolinski
- Institute of Molecular Biosciences, University of Graz, Graz, Austria; BioHealth Field of Excellence, University of Graz, Graz, Austria
| | - Robert Zimmermann
- Institute of Molecular Biosciences, University of Graz, Graz, Austria; BioHealth Field of Excellence, University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Rudolf Zechner
- Institute of Molecular Biosciences, University of Graz, Graz, Austria; BioHealth Field of Excellence, University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Christoph Heier
- Institute of Molecular Biosciences, University of Graz, Graz, Austria; BioHealth Field of Excellence, University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria.
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Mathivanan A, Nachiappan V. Deletion of ORM2 Causes Oleic Acid-Induced Growth Defects in Saccharomyces cerevisiae. Appl Biochem Biotechnol 2023; 195:5916-5932. [PMID: 36719521 DOI: 10.1007/s12010-023-04359-3] [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] [Accepted: 01/10/2023] [Indexed: 02/01/2023]
Abstract
The endoplasmic reticulum (ER) resident proteins of the Orm family (Orm1p and Orm2p) play an essential regulatory role in sphingolipid metabolism and proteostasis of Saccharomyces cerevisiae. Sphingolipid metabolism and its relationship with yeast ORM1 and ORM2 have been studied widely, but its position in phospholipids and neutral lipids requires further studies. We found that the deletion of ORM2 reduced phospholipid levels, but orm1Δ had shown no significant alteration of phospholipids. On the contrary, neutral lipid levels and lipid droplet (LD) numbers were increased in both orm1∆ and orm2∆ cells. Unlike orm1Δ, free fatty acid (FFA) levels were steeply accumulated in orm2∆ cells, and deletion of ORM2 made the cells more sensitive towards oleic acid toxicity. Misregulation of fatty acids has been implicated in the causation of several lipid metabolic disorders. It is imminent to comprehend the control mechanisms of free fatty acid homeostasis and its pathophysiology. Our study has provided experimental evidence of ORM2 role in the lipid and fatty acid metabolism of yeast.
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Affiliation(s)
- Arul Mathivanan
- Biomembrane Lab, Department of Biochemistry, School of Life Sciences, Bharathidasan University, Trichy, 620 024, Tamil Nadu, India
| | - Vasanthi Nachiappan
- Biomembrane Lab, Department of Biochemistry, School of Life Sciences, Bharathidasan University, Trichy, 620 024, Tamil Nadu, India.
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7
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Nagaraj B, James AW, Mathivanan A, Nachiappan V. Impairment of RPN4, a transcription factor, induces ER stress and lipid abnormality in Saccharomyces cerevisiae. Mol Cell Biochem 2023; 478:2127-2139. [PMID: 36703093 DOI: 10.1007/s11010-022-04623-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 11/28/2022] [Indexed: 01/28/2023]
Abstract
Accumulation of misfolded/unfolded proteins in the endoplasmic reticulum (ER) induces ER stress. The transcription factor RPN4 {"Regulatory Particle Non-ATPase"} regulates protein homeostasis by degrading proteins that elude proper folding or assembly via the proteasomal degradation pathway. Here, we studied the lipid alterations exerted by Saccharomyces cerevisiae to mitigate (ER) stress during adaptive responses in rpn4∆ cells. The loss of RPN4-induced ER stress increased phospholipid synthesis, leading to altered membrane structures and accumulation of neutral lipids, causing an increase in lipid droplets (LDs). There was a significant upregulation of genes involved in neutral lipid and membrane lipid synthesis in rpn4∆ cells. Overexpression of RPN4 restored the defects caused by rpn4∆ cells. Thus, our study provides new insight that RPN4 impacts lipid homeostasis.
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Affiliation(s)
- Bhanupriya Nagaraj
- Biomembrane Lab, Department of Biochemistry, School of Life Sciences, Bharathidasan University, Trichy, Tamil Nadu, 620 024, India
| | - Antonisamy William James
- Biomembrane Lab, Department of Biochemistry, School of Life Sciences, Bharathidasan University, Trichy, Tamil Nadu, 620 024, India
- Departments of Medicine and Cancer Biology, College of Medicine & Life Sciences, Toledo, USA
| | - Arul Mathivanan
- Biomembrane Lab, Department of Biochemistry, School of Life Sciences, Bharathidasan University, Trichy, Tamil Nadu, 620 024, India
| | - Vasanthi Nachiappan
- Biomembrane Lab, Department of Biochemistry, School of Life Sciences, Bharathidasan University, Trichy, Tamil Nadu, 620 024, India.
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Venkatraman K, Lee CT, Garcia GC, Mahapatra A, Milshteyn D, Perkins G, Kim KY, Pasolli HA, Phan S, Lippincott-Schwartz J, Ellisman MH, Rangamani P, Budin I. Cristae formation is a mechanical buckling event controlled by the inner membrane lipidome. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.03.13.532310. [PMID: 36993370 PMCID: PMC10054968 DOI: 10.1101/2023.03.13.532310] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
Cristae are high curvature structures in the inner mitochondrial membrane (IMM) that are crucial for ATP production. While cristae-shaping proteins have been defined, analogous mechanisms for lipids have yet to be elucidated. Here we combine experimental lipidome dissection with multi-scale modeling to investigate how lipid interactions dictate IMM morphology and ATP generation. When modulating phospholipid (PL) saturation in engineered yeast strains, we observed a surprisingly abrupt breakpoint in IMM topology driven by a continuous loss of ATP synthase organization at cristae ridges. We found that cardiolipin (CL) specifically buffers the IMM against curvature loss, an effect that is independent of ATP synthase dimerization. To explain this interaction, we developed a continuum model for cristae tubule formation that integrates both lipid and protein-mediated curvatures. The model highlighted a snapthrough instability, which drives IMM collapse upon small changes in membrane properties. We also showed that CL is essential in low oxygen conditions that promote PL saturation. These results demonstrate that the mechanical function of CL is dependent on the surrounding lipid and protein components of the IMM.
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Affiliation(s)
- Kailash Venkatraman
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA 92093
| | - Christopher T Lee
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, CA 92093
| | - Guadalupe C Garcia
- Computational Neurobiology Laboratory, Salk Institute for Biological Studies, La Jolla CA 92097
| | - Arijit Mahapatra
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, CA 92093
| | - Daniel Milshteyn
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA 92093
| | - Guy Perkins
- National Center for Microscopy and Imaging Research, Center for Research in Biological Systems, University of California San Diego, La Jolla, CA 92093
| | - Keun-Young Kim
- National Center for Microscopy and Imaging Research, Center for Research in Biological Systems, University of California San Diego, La Jolla, CA 92093
| | - H Amalia Pasolli
- Howard Hughes Medical Institute, Janelia Research Campus, Ashburn VA 20147
| | - Sebastien Phan
- National Center for Microscopy and Imaging Research, Center for Research in Biological Systems, University of California San Diego, La Jolla, CA 92093
| | | | - Mark H Ellisman
- National Center for Microscopy and Imaging Research, Center for Research in Biological Systems, University of California San Diego, La Jolla, CA 92093
| | - Padmini Rangamani
- Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, CA 92093
| | - Itay Budin
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA 92093
- Lead contact
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9
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Akefe IO, Nyan ES, Adegoke VA, Lamidi IY, Ameh MP, Chidiebere U, Ubah SA, Ajayi IE. Myrtenal improves memory deficits in mice exposed to radiofrequency-electromagnetic radiation during gestational and neonatal development via enhancing oxido-inflammatory, and neurotransmitter functions. Heliyon 2023; 9:e15321. [PMID: 37123912 PMCID: PMC10133755 DOI: 10.1016/j.heliyon.2023.e15321] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2022] [Revised: 03/17/2023] [Accepted: 04/03/2023] [Indexed: 05/02/2023] Open
Abstract
Objective Radiofrequency-electromagnetic radiation (RF-EMR) exposure during gestational and neonatal development may interact with the foetus and neonate considered hypersensitive to RF-EMR, consequently resulting in developmental defects associated with neuropsychological and neurobehavioral disorders, including learning and memory impairment. This study assessed the potential of Myrtenal (Myrt) to improve memory deficits in C57BL/6 mice exposed to RF-EMR during gestational and neonatal development. Method Thirty-five male mice were randomly allocated into 5 cohorts, each comprising of 7 mice. Group I was administered vehicle, Group II: RF-EMR (900 MHz); Group III: RF-EMR (900 MHz) + 100 mg/kg Myrt; Group IV: RF-EMR (900 MHz) + 200 mg/kg Myrt; and Group V: RF-EMR (900 MHz) + donepezil 0.5 mg/kg. Results Myrt treatment improved short-term memory performance in RF-EMR (900 MHz)-exposed mice by augmenting activities of endogenous antioxidant enzymes and proinflammatory cytokines, thereby protecting the brain from oxido-inflammatory stress. Additionally, Myrt restored the homeostasis of neurotransmitters in RF-EMR-exposed animals. Conclusion Results from the present study shows that exposure to RF-EMR impaired short-term memory in animals and altered the response of markers of oxido-inflammatory stress, and neurotransmitters. It is therefore conceivable that the recommendation of Myrt-enriched fruits may offer protective benefits for foeti and neonates prone to RF-EMR exposure.
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Affiliation(s)
- Isaac Oluwatobi Akefe
- Department of Physiology, Biochemistry, and Pharmacology, Faculty of Veterinary Medicine, University of Jos, Jos, Nigeria
| | - Ezekiel Stephen Nyan
- Department of Science and Laboratory Technology, Ekiti State University, Ado Ekiti, Nigeria
| | | | - Ibrahim Yusuf Lamidi
- Department of Veterinary Pharmacology and Toxicology, University of Maiduguri, Maiduguri, Nigeria
| | - Matthew Phillip Ameh
- Department of Veterinary Pharmacology and Toxicology, Ahmadu Bello University, Zaria, Nigeria
| | - Uchendu Chidiebere
- Department of Physiology, Biochemistry, and Pharmacology, Faculty of Veterinary Medicine, University of Jos, Jos, Nigeria
| | | | - Itopa Etudaye Ajayi
- Faculty of Health Sciences, National Open University of Nigeria, Abuja, Nigeria
- Corresponding author.
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10
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Akefe IO, Osborne SL, Matthews B, Wallis TP, Meunier FA. Lipids and Secretory Vesicle Exocytosis. ADVANCES IN NEUROBIOLOGY 2023; 33:357-397. [PMID: 37615874 DOI: 10.1007/978-3-031-34229-5_14] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Abstract
In recent years, the number of studies implicating lipids in the regulation of synaptic vesicle exocytosis has risen considerably. It has become increasingly clear that lipids such as phosphoinositides, lysophospholipids, cholesterol, arachidonic acid and myristic acid play critical regulatory roles in the processes leading up to exocytosis. Lipids may affect membrane fusion reactions by altering the physical properties of the membrane, recruiting key regulatory proteins, concentrating proteins into exocytic "hotspots" or by modulating protein functions allosterically. Discrete changes in phosphoinositides concentration are involved in multiple trafficking events including exocytosis and endocytosis. Lipid-modifying enzymes such as the DDHD2 isoform of phospholipase A1 were recently shown to contribute to memory acquisition via dynamic modifications of the brain lipid landscape. Considering the increasing reports on neurodegenerative disorders associated with aberrant intracellular trafficking, an improved understanding of the control of lipid pathways is physiologically and clinically significant and will afford unique insights into mechanisms and therapeutic methods for neurodegenerative diseases. Consequently, this chapter will discuss the different classes of lipids, phospholipase enzymes, the evidence linking them to synaptic neurotransmitter release and how they act to regulate key steps in the multi-step process leading to neuronal communication and memory acquisition.
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Affiliation(s)
- Isaac O Akefe
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia
| | - Shona L Osborne
- ARC Training Centre for Innovation in Biomedical Imaging Technology (CIBIT), The University of Queensland, St Lucia, QLD, Australia
| | - Benjamin Matthews
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia
| | - Tristan P Wallis
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia
| | - Frédéric A Meunier
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, St Lucia, QLD, Australia.
- School of Biomedical Sciences, The University of Queensland, St Lucia, QLD, Australia.
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11
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Elsayed LEO, Eltazi IZ, Ahmed AE, Stevanin G. Insights into Clinical, Genetic, and Pathological Aspects of Hereditary Spastic Paraplegias: A Comprehensive Overview. Front Mol Biosci 2021; 8:690899. [PMID: 34901147 PMCID: PMC8662366 DOI: 10.3389/fmolb.2021.690899] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2021] [Accepted: 10/19/2021] [Indexed: 12/31/2022] Open
Abstract
Hereditary spastic paraplegias (HSP) are a heterogeneous group of motor neurodegenerative disorders that have the core clinical presentation of pyramidal syndrome which starts typically in the lower limbs. They can present as pure or complex forms with all classical modes of monogenic inheritance reported. To date, there are more than 100 loci/88 spastic paraplegia genes (SPG) involved in the pathogenesis of HSP. New patterns of inheritance are being increasingly identified in this era of huge advances in genetic and functional studies. A wide range of clinical symptoms and signs are now reported to complicate HSP with increasing overall complexity of the clinical presentations considered as HSP. This is especially true with the emergence of multiple HSP phenotypes that are situated in the borderline zone with other neurogenetic disorders. The genetic diagnostic approaches and the utilized techniques leave a diagnostic gap of 25% in the best studies. In this review, we summarize the known types of HSP with special focus on those in which spasticity is the principal clinical phenotype ("SPGn" designation). We discuss their modes of inheritance, clinical phenotypes, underlying genetics, and molecular pathways, providing some observations about therapeutic opportunities gained from animal models and functional studies. This review may pave the way for more analytic approaches that take into consideration the overall picture of HSP. It will shed light on subtle associations that can explain the occurrence of the disease and allow a better understanding of its observed variations. This should help in the identification of future biomarkers, predictors of disease onset and progression, and treatments for both better functional outcomes and quality of life.
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Affiliation(s)
- Liena E. O. Elsayed
- Department of Basic Sciences, College of Medicine, Princess Nourah bint Abdulrahman University [PNU], Riyadh, Saudi Arabia
- Faculty of Medicine, University of Khartoum, Khartoum, Sudan
| | | | - Ammar E. Ahmed
- Faculty of Medicine, University of Khartoum, Khartoum, Sudan
| | - Giovanni Stevanin
- Institut du Cerveau – Paris Brain Institute - ICM, Sorbonne Université, INSERM, CNRS, APHP, Paris, France
- CNRS, INCIA, Université de Bordeaux, Bordeaux, France
- Ecole Pratique des Hautes Etudes, EPHE, PSL Research University, Paris, France
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12
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Dolui AK, Vijayaraj P. Functional Omics Identifies Serine Hydrolases That Mobilize Storage Lipids during Rice Seed Germination. PLANT PHYSIOLOGY 2020; 184:693-708. [PMID: 32817194 PMCID: PMC7536657 DOI: 10.1104/pp.20.00268] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 08/04/2020] [Indexed: 05/10/2023]
Abstract
Elucidating proteolipidome dynamics is crucial for understanding the roles of these molecules in plant physiology and disease. Sequence-based functional annotation of the protein is inadequate, since protein activities depend on posttranslational modification. In this study, we applied a gel-free activity-based protein profiling approach to unravel the active lipases, including other Serine hydrolases (SHs), expressed during seed germination in rice (Oryza sativa). We successfully mapped the active sites of 43 active SHs encompassing lipases/esterases, GDSL lipases, proteases, Ser carboxypeptidases, ABHD protein, pectin acetylesterase, and other SHs. The mRNA expression levels of those genes encoding the identified SHs were monitored using microarray analysis. The lipidome analysis revealed distinct patterns of molecular species distribution in individual lipid classes and displayed the metabolic connections between lipid mobilization and rice seedling growth. Changes in the mobilization of storage lipids and their molecular species remodeling were correlated with the expression of the identified lipases and their lipase activity in a time-dependent manner. The physiological significance of the identified SHs was explored during biotic stress with Fusarium verticillioides infection. The fungal infection significantly reduced lipase activity and lipid mobilization, thus impairing the rice seedling. Collectively, our data demonstrate application of the functional proteome strategy along with the shotgun lipidome approach for the identification of active SHs, and thus for deciphering the role of lipid homeostasis during rice seed germination.
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Affiliation(s)
- Achintya Kumar Dolui
- Lipid and Nutrition Laboratory, Department of Lipid Science, Council of Scientific and Industrial Research-Central Food Technological Research Institute, Mysore, Karnataka, 570020, India
- Academy of Scientific and Innovative Research, Ghaziabad, 201002, Uttar Pradesh, India
| | - Panneerselvam Vijayaraj
- Lipid and Nutrition Laboratory, Department of Lipid Science, Council of Scientific and Industrial Research-Central Food Technological Research Institute, Mysore, Karnataka, 570020, India
- Academy of Scientific and Innovative Research, Ghaziabad, 201002, Uttar Pradesh, India
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13
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Rickman OJ, Baple EL, Crosby AH. Lipid metabolic pathways converge in motor neuron degenerative diseases. Brain 2020; 143:1073-1087. [PMID: 31848577 PMCID: PMC7174042 DOI: 10.1093/brain/awz382] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 09/11/2019] [Accepted: 10/01/2019] [Indexed: 12/11/2022] Open
Abstract
Motor neuron diseases (MNDs) encompass an extensive and heterogeneous group of upper and/or lower motor neuron degenerative disorders, in which the particular clinical outcomes stem from the specific neuronal component involved in each condition. While mutations in a large number of molecules associated with lipid metabolism are known to be implicated in MNDs, there remains a lack of clarity regarding the key functional pathways involved, and their inter-relationships. This review highlights evidence that defines defects within two specific lipid (cholesterol/oxysterol and phosphatidylethanolamine) biosynthetic cascades as being centrally involved in MND, particularly hereditary spastic paraplegia. We also identify how other MND-associated molecules may impact these cascades, in particular through impaired organellar interfacing, to propose ‘subcellular lipidome imbalance’ as a likely common pathomolecular theme in MND. Further exploration of this mechanism has the potential to identify new therapeutic targets and management strategies for modulation of disease progression in hereditary spastic paraplegias and other MNDs.
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Affiliation(s)
- Olivia J Rickman
- Medical Research (Level 4), RILD Wellcome Wolfson Centre, University of Exeter Medical School, Royal Devon and Exeter NHS Foundation Trust, Barrack Road, Exeter, EX2 5DW, UK
| | - Emma L Baple
- Medical Research (Level 4), RILD Wellcome Wolfson Centre, University of Exeter Medical School, Royal Devon and Exeter NHS Foundation Trust, Barrack Road, Exeter, EX2 5DW, UK
| | - Andrew H Crosby
- Medical Research (Level 4), RILD Wellcome Wolfson Centre, University of Exeter Medical School, Royal Devon and Exeter NHS Foundation Trust, Barrack Road, Exeter, EX2 5DW, UK
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14
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Patton-Vogt J, de Kroon AIPM. Phospholipid turnover and acyl chain remodeling in the yeast ER. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1865:158462. [PMID: 31146038 PMCID: PMC10716787 DOI: 10.1016/j.bbalip.2019.05.006] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 05/01/2019] [Accepted: 05/15/2019] [Indexed: 12/14/2022]
Abstract
The turnover of phospholipids plays an essential role in membrane lipid homeostasis by impacting both lipid head group and acyl chain composition. This review focusses on the degradation and acyl chain remodeling of the major phospholipid classes present in the ER membrane of the reference eukaryote Saccharomyces cerevisiae, i.e. phosphatidylcholine (PC), phosphatidylinositol (PI) and phosphatidylethanolamine (PE). Phospholipid turnover reactions are introduced, and the occurrence and important functions of phospholipid remodeling in higher eukaryotes are briefly summarized. After presenting an inventory of established mechanisms of phospholipid acyl chain exchange, current knowledge of phospholipid degradation and remodeling by phospholipases and acyltransferases localized to the yeast ER is summarized. PC is subject to the PC deacylation-reacylation remodeling pathway (PC-DRP) involving a phospholipase B, the recently identified glycerophosphocholine acyltransferase Gpc1p, and the broad specificity acyltransferase Ale1p. PI is post-synthetically enriched in C18:0 acyl chains by remodeling reactions involving Cst26p. PE may undergo turnover by the phospholipid: diacylglycerol acyltransferase Lro1p as first step in acyl chain remodeling. Clues as to the functions of phospholipid acyl chain remodeling are discussed.
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Affiliation(s)
- Jana Patton-Vogt
- Department of Biological Sciences, Duquesne University, Pittsburgh, PA, USA
| | - Anton I P M de Kroon
- Membrane Biochemistry & Biophysics, Bijvoet Center and Institute of Biomembranes, Utrecht University, Utrecht, the Netherlands.
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15
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Lian J, Schultz C, Cao M, HamediRad M, Zhao H. Multi-functional genome-wide CRISPR system for high throughput genotype-phenotype mapping. Nat Commun 2019; 10:5794. [PMID: 31857575 PMCID: PMC6923430 DOI: 10.1038/s41467-019-13621-4] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2018] [Accepted: 11/12/2019] [Indexed: 01/20/2023] Open
Abstract
Genome-scale engineering is an indispensable tool to understand genome functions due to our limited knowledge of cellular networks. Unfortunately, most existing methods for genome-wide genotype–phenotype mapping are limited to a single mode of genomic alteration, i.e. overexpression, repression, or deletion. Here we report a multi-functional genome-wide CRISPR (MAGIC) system to precisely control the expression level of defined genes to desired levels throughout the whole genome. By combining the tri-functional CRISPR system and array-synthesized oligo pools, MAGIC is used to create, to the best of our knowledge, one of the most comprehensive and diversified genomic libraries in yeast ever reported. The power of MAGIC is demonstrated by the identification of previously uncharacterized genetic determinants of complex phenotypes, particularly those having synergistic interactions when perturbed to different expression levels. MAGIC represents a powerful synthetic biology tool to investigate fundamental biological questions as well as engineer complex phenotypes for biotechnological applications. Genome-scale engineering is generally limited to single methods of alteration such as overexpression, repression or deletion. Here the authors present a tri-functional CRISPR system that can engineer complex synergistic interactions in a genome-wide manner.
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Affiliation(s)
- Jiazhang Lian
- Department of Chemical and Biomolecular Engineering, Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.,Key Laboratory of Biomass Chemical Engineering of Ministry of Education, College of Chemical and Biological Engineering, Zhejiang University, 310027, Hangzhou, China
| | - Carl Schultz
- Department of Chemical and Biomolecular Engineering, Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Mingfeng Cao
- Department of Chemical and Biomolecular Engineering, Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA
| | - Mohammad HamediRad
- Department of Chemical and Biomolecular Engineering, Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.,Lifefoundry Inc., 60 Hazelwood Dr., Champaign, IL, 61820, USA
| | - Huimin Zhao
- Department of Chemical and Biomolecular Engineering, Carl R. Woese Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA. .,Departments of Chemistry, Biochemistry, and Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
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16
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Martins TS, Costa V, Pereira C. Signaling pathways governing iron homeostasis in budding yeast. Mol Microbiol 2018; 109:422-432. [DOI: 10.1111/mmi.14009] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/13/2018] [Indexed: 12/13/2022]
Affiliation(s)
- Telma S. Martins
- I3S-Instituto de Investigação e Inovação em Saúde; Universidade do Porto; Porto Portugal
- IBMC-Instituto de Biologia Molecular e Celular; Universidade do Porto; Porto Portugal
| | - Vítor Costa
- I3S-Instituto de Investigação e Inovação em Saúde; Universidade do Porto; Porto Portugal
- IBMC-Instituto de Biologia Molecular e Celular; Universidade do Porto; Porto Portugal
- Departamento de Biologia Molecular; Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto; Porto Portugal
| | - Clara Pereira
- I3S-Instituto de Investigação e Inovação em Saúde; Universidade do Porto; Porto Portugal
- IBMC-Instituto de Biologia Molecular e Celular; Universidade do Porto; Porto Portugal
- Departamento de Biologia Molecular; Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto; Porto Portugal
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17
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Morisada S, Nishida I, Kawamukai M, Horiuchi H, Fukuda R. Suppression of respiratory growth defect of mutant deficient in mitochondrial phospholipase A1 by overexpression of genes involved in coenzyme Q synthesis in Saccharomyces cerevisiae. Biosci Biotechnol Biochem 2018; 82:1633-1639. [DOI: 10.1080/09168451.2018.1476124] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
ABSTRACT
DDL1 encodes a mitochondrial phospholipase A1 involved in acyl chain remodeling of mitochondrial phospholipids and degradation of cardiolipin in Saccharomyces cerevisiae. The deletion of DDL1 leads to respiratory growth defects. To elucidate the physiological role of DDL1, we screened for genes that, when overexpressed, suppress the respiratory growth defect of the DDL1 deletion mutant. Introduction of COQ8, COQ9, or COQ5, which are involved in coenzyme Q (CoQ) synthesis, using a multicopy vector suppressed the respiratory growth defect of the DDL1 deletion mutant. In contrast, introduction of COQ8 using a multicopy vector did not accelerate the growth of the deletion mutants of TAZ1 or CLD1, which encode an acyltransferase or phospholipase A2, respectively, involved in the remodeling of cardiolipin. These results suggest genetic interactions between the mitochondrial phospholipase A1 gene and the genes involved in CoQ synthesis.
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Affiliation(s)
- Shiho Morisada
- Department of Biotechnology, The University of Tokyo, Tokyo, Japan
| | - Ikuhisa Nishida
- Faculty of Life and Environmental Science, Department of Life Sciences, Shimane University, Matsue, Japan
| | - Makoto Kawamukai
- Faculty of Life and Environmental Science, Department of Life Sciences, Shimane University, Matsue, Japan
| | | | - Ryouichi Fukuda
- Department of Biotechnology, The University of Tokyo, Tokyo, Japan
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18
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Loss of DDHD2, whose mutation causes spastic paraplegia, promotes reactive oxygen species generation and apoptosis. Cell Death Dis 2018; 9:797. [PMID: 30038238 PMCID: PMC6056544 DOI: 10.1038/s41419-018-0815-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2017] [Revised: 05/08/2018] [Accepted: 06/21/2018] [Indexed: 11/30/2022]
Abstract
DDHD2/KIAA0725p is a mammalian intracellular phospholipase A1 that exhibits phospholipase and lipase activities. Mutation of the DDHD2 gene causes hereditary spastic paraplegia (SPG54), an inherited neurological disorder characterized by lower limb spasticity and weakness. Although previous studies demonstrated lipid droplet accumulation in the brains of SPG54 patients and DDHD2 knockout mice, the cause of SPG54 remains elusive. Here, we show that ablation of DDHD2 in mice induces age-dependent apoptosis of motor neurons in the spinal cord. In vitro, motor neurons and embryonic fibroblasts from DDHD2 knockout mice fail to survive and are susceptible to apoptotic stimuli. Chemical and probe-based analysis revealed a substantial decrease in cardiolipin content and an increase in reactive oxygen species generation in DDHD2 knockout cells. Reactive oxygen species production in DDHD2 knockout cells was reversed by the expression of wild-type DDHD2, but not by an active-site DDHD2 mutant, DDHD2 mutants related to hereditary spastic paraplegia, or DDHD1, another member of the intracellular phospholipase A1 family whose mutation also causes spastic paraplegia (SPG28). Our results demonstrate the protective role of DDHD2 for mitochondrial integrity and provide a clue to the pathogenic mechanism of SPG54.
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19
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Converging cellular themes for the hereditary spastic paraplegias. Curr Opin Neurobiol 2018; 51:139-146. [PMID: 29753924 DOI: 10.1016/j.conb.2018.04.025] [Citation(s) in RCA: 80] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Revised: 03/22/2018] [Accepted: 04/25/2018] [Indexed: 01/08/2023]
Abstract
Hereditary spastic paraplegias (HSPs) are neurologic disorders characterized by prominent lower-extremity spasticity, resulting from a length-dependent axonopathy of corticospinal upper motor neurons. They are among the most genetically-diverse neurologic disorders, with >80 distinct genetic loci and over 60 identified genes. Studies investigating the molecular pathogenesis underlying HSPs have emphasized the importance of converging cellular pathogenic themes in the most common forms of HSP, providing compelling targets for therapy. Most notably, these include organelle shaping and biogenesis as well as membrane and cargo trafficking.
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20
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Rao MJ, Srinivasan M, Rajasekharan R. Cell size is regulated by phospholipids and not by storage lipids in Saccharomyces cerevisiae. Curr Genet 2018. [PMID: 29536156 DOI: 10.1007/s00294-018-0821-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Cell size and morphology are key adaptive features that influence almost all aspects of cellular physiology such as cell cycle and lipid metabolism. Here we report the role of a transcription factor Suppressor Phenotype of Ty elements insertion 10 (SPT10) of Saccharomyces cerevisiae in regulating cell cycle, cell size and lipid metabolism in concert, in addition to its defined role of histone gene expression. Morphological and biochemical analyses of spt10Δ strain show an abnormal cell size, cell cycle and lipid levels. The expression of Spt10p in spt10Δ strain helps the cell revert to typical wild-type phenotypes. SPT10 controls lipid metabolism by negatively regulating the expression of lipid biosynthetic genes, and positively regulating the expression of the lipid hydrolyzing genes. Spt10p helps in maintaining the cell size by regulating the amount of carbon flux into the phospholipid constituents of the cell membranes. On the contrary, storage lipids have no role in regulating the cell size. An exogenous supply of phosphatidic acid increases the cell size, proving the positive impact of the phospholipids on cell size modulation. SPT10 affects cell cycle, cell size and lipid metabolism by an orchestrated transcriptional regulation of the corresponding genes.
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Affiliation(s)
- Monala Jayaprakash Rao
- Department of Lipid Science, Lipidomics Center, CSIR-Central Food Technological Research Institute, Mysore, Karnataka, 570020, India.,Academy of Scientific and Innovative Research, CSIR-Central Food Technological Research Institute, Mysore, Karnataka, 570020, India
| | - Malathi Srinivasan
- Department of Lipid Science, Lipidomics Center, CSIR-Central Food Technological Research Institute, Mysore, Karnataka, 570020, India.,Academy of Scientific and Innovative Research, CSIR-Central Food Technological Research Institute, Mysore, Karnataka, 570020, India
| | - Ram Rajasekharan
- Department of Lipid Science, Lipidomics Center, CSIR-Central Food Technological Research Institute, Mysore, Karnataka, 570020, India. .,Academy of Scientific and Innovative Research, CSIR-Central Food Technological Research Institute, Mysore, Karnataka, 570020, India.
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21
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Yadav PK, Rajvanshi PK, Rajasekharan R. The role of yeast m 6A methyltransferase in peroxisomal fatty acid oxidation. Curr Genet 2017; 64:417-422. [PMID: 29043484 DOI: 10.1007/s00294-017-0769-5] [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: 10/11/2017] [Revised: 10/13/2017] [Accepted: 10/15/2017] [Indexed: 01/08/2023]
Abstract
The precise and controlled regulation of gene expression at transcriptional and post-transcriptional levels is crucial for the eukaryotic cell survival and functions. In eukaryotes, more than 100 types of post-transcriptional RNA modifications have been identified. The N6-methyladenosine (m6A) modification in mRNA is among the most common post-transcriptional RNA modifications known in eukaryotic organisms, and the m6A RNA modification can regulate gene expression. The role of yeast m6A methyltransferase (Ime4) in meiosis, sporulation, triacylglycerol metabolism, vacuolar morphology, and mitochondrial functions has been reported. Stress triggers triacylglycerol accumulation as lipid droplets. Lipid droplets are physically connected to the different organelles such as endoplasmic reticulum, mitochondria, and peroxisomes. However, the physiological relevance of these physical interactions remains poorly understood. In yeast, peroxisome is the sole site of fatty acid β-oxidation. The metabolic status of the cell readily governs the number and physiological function of peroxisomes. Under low-glucose or stationary-phase conditions, peroxisome biogenesis and proliferation increase in the cells. Therefore, we hypothesized a possible role of Ime4 in the peroxisomal functions. There is no report on the role of Ime4 in peroxisomal biology. Here, we report that IME4 gene deletion causes peroxisomal dysfunction under stationary-phase conditions in Saccharomyces cerevisiae; besides, the ime4Δ cells showed a significant decrease in the expression of the key genes involved in peroxisomal β-oxidation compared to the wild-type cells. Therefore, identification and determination of the target genes of Ime4 that are directly involved in the peroxisomal biogenesis, morphology, and functions will pave the way to better understand the role of m6A methylation in peroxisomal biology.
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Affiliation(s)
- Pradeep Kumar Yadav
- Lipidomic Centre, Department of Lipid Science, CSIR-Central Food Technological Research Institute (CFTRI), Council of Scientific and Industrial Research, Mysore, Karnataka, 570020, India.,Academy of Scientific and Innovative Research, CSIR-CFTRI, Mysore, India
| | - Praveen Kumar Rajvanshi
- Lipidomic Centre, Department of Lipid Science, CSIR-Central Food Technological Research Institute (CFTRI), Council of Scientific and Industrial Research, Mysore, Karnataka, 570020, India.,Academy of Scientific and Innovative Research, CSIR-CFTRI, Mysore, India
| | - Ram Rajasekharan
- Lipidomic Centre, Department of Lipid Science, CSIR-Central Food Technological Research Institute (CFTRI), Council of Scientific and Industrial Research, Mysore, Karnataka, 570020, India. .,Academy of Scientific and Innovative Research, CSIR-CFTRI, Mysore, India.
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22
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Yadav PK, Rajasekharan R. The m 6A methyltransferase Ime4 and mitochondrial functions in yeast. Curr Genet 2017; 64:353-357. [PMID: 28975387 DOI: 10.1007/s00294-017-0758-8] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Revised: 09/25/2017] [Accepted: 09/25/2017] [Indexed: 12/21/2022]
Abstract
In eukaryotes, the precise transcriptional and post-transcriptional regulations of gene expression are crucial for the developmental processes. More than 100 types of post-transcriptional RNA modifications have been identified in eukaryotes. The deposition of N6-methyladenosine (m6A) into mRNA is among the most common post-transcriptional RNA modifications known in eukaryotes. It has been reported that m6A RNA modification can regulate gene expression. The role of yeast m6A methyltransferase (Ime4) in meiosis and sporulation in diploid cells is very well proven, but its physiological role in haploid cells has remained unknown until recently. Previously, we have shown that Ime4 epitranscriptionally regulates triacylglycerol (TAG) metabolism and vacuolar morphology in haploid cells. Mitochondrial dysfunction leads to TAG accumulation as lipid droplets (LDs) in the cells; besides, LDs are physically connected to the mitochondria. As of now there are no reports on the role of Ime4 in mitochondrial biology. Here we report the important role played by Ime4 in the mitochondrial morphology and functions in Saccharomyces cerevisiae. The confocal microscopic analysis showed that IME4 gene deletion causes mitochondrial fragmentation; besides, the ime4Δ cells showed a significant decrease in cytochrome c oxidase and citrate synthase activities compared to the wild-type cells. IME4 gene deletion causes mitochondrial dysfunction, and it will be interesting to find out the target genes of Ime4 related to the mitochondrial biology. The determination of the role of Ime4 and its targets in mitochondrial biology could probably help in formulating potential cures for the mitochondria-linked rare genetic disorders.
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Affiliation(s)
- Pradeep Kumar Yadav
- Lipidomic Centre, Department of Lipid Science, CSIR-Central Food Technological Research Institute (CFTRI), Mysore, Karnataka, 570020, India.,Academy of Scientific and Innovative Research, CSIR-CFTRI, Mysore, India
| | - Ram Rajasekharan
- Lipidomic Centre, Department of Lipid Science, CSIR-Central Food Technological Research Institute (CFTRI), Mysore, Karnataka, 570020, India. .,Academy of Scientific and Innovative Research, CSIR-CFTRI, Mysore, India.
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Rajvanshi PK, Arya M, Rajasekharan R. The stress-regulatory transcription factors Msn2 and Msn4 regulate fatty acid oxidation in budding yeast. J Biol Chem 2017; 292:18628-18643. [PMID: 28924051 DOI: 10.1074/jbc.m117.801704] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2017] [Revised: 09/12/2017] [Indexed: 11/06/2022] Open
Abstract
The transcription factors Msn2 and Msn4 (multicopy suppressor of SNF1 mutation proteins 2 and 4) bind the stress-response element in gene promoters in the yeast Saccharomyces cerevisiae However, the roles of Msn2/4 in primary metabolic pathways such as fatty acid β-oxidation are unclear. Here, in silico analysis revealed that the promoters of most genes involved in the biogenesis, function, and regulation of the peroxisome contain Msn2/4-binding sites. We also found that transcript levels of MSN2/MSN4 are increased in glucose-depletion conditions and that during growth in nonpreferred carbon sources, Msn2 is constantly localized to the nucleus in wild-type cells. Of note, the double mutant msn2Δmsn4Δ exhibited a severe growth defect when grown with oleic acid as the sole carbon source and had reduced transcript levels of major β-oxidation genes. ChIP indicated that Msn2 has increased occupancy on the promoters of β-oxidation genes in glucose-depleted conditions, and in vivo reporter gene analysis indicated reduced expression of these genes in msn2Δmsn4Δ cells. Moreover, mobility shift assays revealed that Msn4 binds β-oxidation gene promoters. Immunofluorescence microscopy with anti-peroxisome membrane protein antibodies disclosed that the msn2Δmsn4Δ strain had fewer peroxisomes than the wild type, and lipid analysis indicated that the msn2Δmsn4Δ strain had increased triacylglycerol and steryl ester levels. Collectively, our data suggest that Msn2/Msn4 transcription factors activate expression of the genes involved in fatty acid oxidation. Because glucose sensing, signaling, and fatty acid β-oxidation pathways are evolutionarily conserved throughout eukaryotes, the msn2Δmsn4Δ strain could therefore be a good model system for further study of these critical processes.
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Affiliation(s)
- Praveen Kumar Rajvanshi
- From the Department of Lipid Science of the Lipidomic Centre and.,the Academy of Scientific and Innovative Research, Council of Scientific and Industrial Research-Central Food Technological Research Institute, Mysuru 570020, Karnataka, India
| | - Madhuri Arya
- From the Department of Lipid Science of the Lipidomic Centre and.,the Academy of Scientific and Innovative Research, Council of Scientific and Industrial Research-Central Food Technological Research Institute, Mysuru 570020, Karnataka, India
| | - Ram Rajasekharan
- From the Department of Lipid Science of the Lipidomic Centre and .,the Academy of Scientific and Innovative Research, Council of Scientific and Industrial Research-Central Food Technological Research Institute, Mysuru 570020, Karnataka, India
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24
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Yadav PK, Rajasekharan R. The m 6A methyltransferase Ime4 epitranscriptionally regulates triacylglycerol metabolism and vacuolar morphology in haploid yeast cells. J Biol Chem 2017; 292:13727-13744. [PMID: 28655762 DOI: 10.1074/jbc.m117.783761] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 06/02/2017] [Indexed: 12/20/2022] Open
Abstract
N6-Methyladenosine (m6A) is among the most common modifications in eukaryotic mRNA. The role of yeast m6A methyltransferase, Ime4, in meiosis and sporulation in diploid strains is very well studied, but its role in haploid strains has remained unknown. Here, with the help of an immunoblotting strategy and Ime4-GFP protein localization studies, we establish the physiological role of Ime4 in haploid cells. Our data showed that Ime4 epitranscriptionally regulates triacylglycerol metabolism and vacuolar morphology through the long-chain fatty acyl-CoA synthetase Faa1, independently of the RNA methylation complex (MIS complex). The MIS complex consists of the Ime4, Mum2, and Slz1 proteins. Our affinity enrichment strategy (methylated RNA immunoprecipitation assays) using m6A polyclonal antibodies coupled with mRNA isolation, quantitative real-time PCR, and standard PCR analyses confirmed the presence of m6A-modified FAA1 transcripts in haploid yeast cells. The term "epitranscriptional regulation" encompasses the RNA modification-mediated regulation of genes. Moreover, we demonstrate that the Aft2 transcription factor up-regulates FAA1 expression. Because the m6A methylation machinery is fundamentally conserved throughout eukaryotes, our findings will help advance the rapidly emerging field of RNA epitranscriptomics. The metabolic link identified here between m6A methylation and triacylglycerol metabolism via the Ime4 protein provides new insights into lipid metabolism and the pathophysiology of lipid-related metabolic disorders, such as obesity. Because the yeast vacuole is an analogue of the mammalian lysosome, our findings pave the way to better understand the role of m6A methylation in lysosome-related functions and diseases.
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Affiliation(s)
- Pradeep Kumar Yadav
- From the Lipidomic Centre, Department of Lipid Science, and.,the Academy of Scientific and Innovative Research, CSIR-Central Food Technological Research Institute, Mysuru, Karnataka 570020, India
| | - Ram Rajasekharan
- From the Lipidomic Centre, Department of Lipid Science, and .,the Academy of Scientific and Innovative Research, CSIR-Central Food Technological Research Institute, Mysuru, Karnataka 570020, India
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25
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Yadav PK, Rajasekharan R. Cardiolipin deficiency causes triacylglycerol accumulation in Saccharomyces cerevisiae. Mol Cell Biochem 2017; 434:89-103. [PMID: 28432553 DOI: 10.1007/s11010-017-3039-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2017] [Accepted: 04/12/2017] [Indexed: 01/05/2023]
Abstract
In yeast, the synthesis of cardiolipin (CL) and phosphatidylethanolamine (PE) occurs mainly in mitochondria. CL and PE have overlapping functions, and they are required for mitochondrial function. PE is physiologically linked with triacylglycerol (TAG) metabolism in Saccharomyces cerevisiae, involving an acyl-CoA-independent pathway through the phospholipid:diacylglycerol acyltransferase activity of the Lro1 protein. There is no report on the physiological link between CL and TAG metabolism. Here we report a metabolic link between CL and TAG accumulation in the S. cerevisiae. Our data indicated that CL deficiency causes TAG accumulation, involving an acyl-CoA-dependent pathway through the diacylglycerol acyltransferase activity of the Dga1 protein with no changes in the TAG molecular species. The DGA1 gene deletion from the CL-deficient strains reduced the TAG levels. Data from in vitro and in vivo analyses showed that CL did not affect the enzymatic activity of Dga1. Our data also showed that CL deficiency leads to the up-regulation of acetyl-CoA synthetase genes (ACS1 and ACS2) of the cytosolic pyruvate dehydrogenase bypass pathway. This study establishes a physiological link between CL and TAG metabolism in S. cerevisiae.
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Affiliation(s)
- Pradeep Kumar Yadav
- Lipidomic Centre, Department of Lipid Science, CSIR-Central Food Technological Research Institute (CFTRI), Council of Scientific and Industrial Research, Mysore, Karnataka, 570020, India
- Academy of Scientific & Innovative Research, CSIR-CFTRI, Mysore, India
| | - Ram Rajasekharan
- Lipidomic Centre, Department of Lipid Science, CSIR-Central Food Technological Research Institute (CFTRI), Council of Scientific and Industrial Research, Mysore, Karnataka, 570020, India.
- Academy of Scientific & Innovative Research, CSIR-CFTRI, Mysore, India.
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Gáliková M, Klepsatel P, Münch J, Kühnlein RP. Spastic paraplegia-linked phospholipase PAPLA1 is necessary for development, reproduction, and energy metabolism in Drosophila. Sci Rep 2017; 7:46516. [PMID: 28422159 PMCID: PMC5395975 DOI: 10.1038/srep46516] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 03/17/2017] [Indexed: 12/01/2022] Open
Abstract
The human PAPLA1 phospholipase family is associated with hereditary spastic paraplegia (HSP), a neurodegenerative syndrome characterized by progressive spasticity and weakness of the lower limbs. Taking advantage of a new Drosophila PAPLA1 mutant, we describe here novel functions of this phospholipase family in fly development, reproduction, and energy metabolism. Loss of Drosophila PAPLA1 reduces egg hatchability, pre-adult viability, developmental speed, and impairs reproductive functions of both males and females. In addition, our work describes novel metabolic roles of PAPLA1, manifested as decreased food intake, lower energy expenditure, and reduced ATP levels of the mutants. Moreover, PAPLA1 has an important role in the glycogen metabolism, being required for expression of several regulators of carbohydrate metabolism and for glycogen storage. In contrast, global loss of PAPLA1 does not affect fat reserves in adult flies. Interestingly, several of the PAPLA1 phenotypes in fly are reminiscent of symptoms described in some HSP patients, suggesting evolutionary conserved functions of PAPLA1 family in the affected processes. Altogether, this work reveals novel physiological functions of PAPLA1, which are likely evolutionary conserved from flies to humans.
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Affiliation(s)
- Martina Gáliková
- Max Planck Institute for Biophysical Chemistry, Research Group Molecular Physiology, Am Faßberg 11, D-37077 Göttingen, Germany.,Max Planck Institute for Biophysical Chemistry, Department of Molecular Developmental Biology, Am Faßberg 11, D-37077 Göttingen, Germany.,Stockholm University, Department of Zoology, Svante Arrhenius väg 18B, S-106 91 Stockholm, Sweden
| | - Peter Klepsatel
- Max Planck Institute for Biophysical Chemistry, Research Group Molecular Physiology, Am Faßberg 11, D-37077 Göttingen, Germany
| | - Judith Münch
- Max Planck Institute for Biophysical Chemistry, Research Group Molecular Physiology, Am Faßberg 11, D-37077 Göttingen, Germany.,University of Leipzig, Faculty of Chemistry and Mineralogy, Johannisallee 29, D-04103 Leipzig, Germany
| | - Ronald P Kühnlein
- Max Planck Institute for Biophysical Chemistry, Research Group Molecular Physiology, Am Faßberg 11, D-37077 Göttingen, Germany.,University of Graz, Institute of Molecular Biosciences, Humboldtstraße 50/2.OG, A-8010 Graz, Austria
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