1
|
Schengrund CL. Sphingolipids: Less Enigmatic but Still Many Questions about the Role(s) of Ceramide in the Synthesis/Function of the Ganglioside Class of Glycosphingolipids. Int J Mol Sci 2024; 25:6312. [PMID: 38928016 PMCID: PMC11203820 DOI: 10.3390/ijms25126312] [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: 04/23/2024] [Revised: 05/17/2024] [Accepted: 05/27/2024] [Indexed: 06/28/2024] Open
Abstract
While much has been learned about sphingolipids, originally named for their sphinx-like enigmatic properties, there are still many unanswered questions about the possible effect(s) of the composition of ceramide on the synthesis and/or behavior of a glycosphingolipid (GSL). Over time, studies of their ceramide component, the sphingoid base containing the lipid moiety of GSLs, were frequently distinct from those performed to ascertain the roles of the carbohydrate moieties. Due to the number of classes of GSLs that can be derived from ceramide, this review focuses on the possible role(s) of ceramide in the synthesis/function of just one GSL class, derived from glucosylceramide (Glc-Cer), namely sialylated ganglio derivatives, initially characterized and named gangliosides (GGs) due to their presence in ganglion cells. While much is known about their synthesis and function, much is still being learned. For example, it is only within the last 15-20 years or so that the mechanism by which the fatty acyl component of ceramide affected its transport to different sites in the Golgi, where it is used for the synthesis of Glu- or galactosyl-Cer (Gal-Cer) and more complex GSLs, was defined. Still to be fully addressed are questions such as (1) whether ceramide composition affects the transport of partially glycosylated GSLs to sites where their carbohydrate chain can be elongated or affects the activity of glycosyl transferases catalyzing that elongation; (2) what controls the differences seen in the ceramide composition of GGs that have identical carbohydrate compositions but vary in that of their ceramide and vice versa; (3) how alterations in ceramide composition affect the function of membrane GGs; and (4) how this knowledge might be applied to the development of therapies for treating diseases that correlate with abnormal expression of GGs. The availability of an updatable data bank of complete structures for individual classes of GSLs found in normal tissues as well as those associated with disease would facilitate research in this area.
Collapse
Affiliation(s)
- Cara-Lynne Schengrund
- Department of Biochemistry and Molecular Biology, The Pennsylvania State University College of Medicine, Hershey, PA 17033, USA
| |
Collapse
|
2
|
Nurmi H, Backman AE, Halin J, Lönnfors M, Blom T, Roos-Mattjus P, Mattjus P. Glycolipid transfer protein knockout disrupts vesicle trafficking to the plasma membrane. J Biol Chem 2023; 299:104607. [PMID: 36924944 PMCID: PMC10140181 DOI: 10.1016/j.jbc.2023.104607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2022] [Revised: 02/16/2023] [Accepted: 03/06/2023] [Indexed: 03/17/2023] Open
Abstract
The glycolipid transfer protein (GLTP) has been linked to many cellular processes aside from its best-known in vitro function as a lipid transport protein. It has been proposed to act as a sensor and regulator of glycosphingolipid homeostasis in cells. Furthermore, through its previously determined interaction with the endoplasmic reticulum (ER) membrane protein VAP-A (vesicle-associated membrane protein-associated protein A), GLTP may also be involved in facilitating vesicular transport in cells. In this study, we characterized the phenotype of CRISPR/Cas9-mediated GLTP knockout HeLa cells. We showed that motility, three-dimensional growth, and cellular metabolism were all altered by GLTP knockout. Expression of a GLTP mutant incapable of binding VAP disrupted cell spheroid formation, indicating that the GLTP-VAP interaction is linked to cellular adhesion, cohesion, and three-dimensional growth. Most notably, we found evidence that GLTP, through its interaction with VAP-A, affects vesicular trafficking, marking the first cellular process discovered to be directly impacted by a change in GLTP expression.
Collapse
Affiliation(s)
- Henrik Nurmi
- Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Artillerigatan 6A, III, 20520 Turku, Finland
| | - AndersP E Backman
- Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Artillerigatan 6A, III, 20520 Turku, Finland
| | - Josefin Halin
- Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Artillerigatan 6A, III, 20520 Turku, Finland
| | - Max Lönnfors
- Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Artillerigatan 6A, III, 20520 Turku, Finland
| | - Tomas Blom
- Department of Anatomy and Research Programs Unit, Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | - Pia Roos-Mattjus
- Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Artillerigatan 6A, III, 20520 Turku, Finland
| | - Peter Mattjus
- Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Artillerigatan 6A, III, 20520 Turku, Finland.
| |
Collapse
|
3
|
Guzman G, Creek C, Farley S, Tafesse FG. Genetic Tools for Studying the Roles of Sphingolipids in Viral Infections. Methods Mol Biol 2022; 2610:1-16. [PMID: 36534277 DOI: 10.1007/978-1-0716-2895-9_1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Sphingolipids are a critical family of membrane lipids with diverse functions in eukaryotic cells, and a growing body of literature supports that these lipids play essential roles during the lifecycles of viruses. While small molecule inhibitors of sphingolipid synthesis and metabolism are widely used, the advent of CRISPR-based genomic editing techniques allows for nuanced exploration into the manners in which sphingolipids influence various stages of viral infections. Here we describe some of these critical considerations needed in designing studies utilizing genomic editing techniques for manipulating the sphingolipid metabolic pathway, as well as the current body of literature regarding how viruses depend on the products of this pathway. Here, we highlight the ways in which sphingolipids affect viruses as these pathogens interact with and influence their host cell and describe some of the many open questions remaining in the field.
Collapse
Affiliation(s)
- Gaelen Guzman
- Department of Molecular Microbiology & Immunology, Oregon Health & Science University, Portland, OR, USA
| | - Cameron Creek
- Department of Molecular Microbiology & Immunology, Oregon Health & Science University, Portland, OR, USA
| | - Scotland Farley
- Department of Molecular Microbiology & Immunology, Oregon Health & Science University, Portland, OR, USA
| | - Fikadu G Tafesse
- Department of Molecular Microbiology & Immunology, Oregon Health & Science University, Portland, OR, USA.
| |
Collapse
|
4
|
Wenzel EM, Elfmark LA, Stenmark H, Raiborg C. ER as master regulator of membrane trafficking and organelle function. J Cell Biol 2022; 221:213468. [PMID: 36108241 PMCID: PMC9481738 DOI: 10.1083/jcb.202205135] [Citation(s) in RCA: 40] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 08/16/2022] [Accepted: 08/22/2022] [Indexed: 12/13/2022] Open
Abstract
The endoplasmic reticulum (ER), which occupies a large portion of the cytoplasm, is the cell’s main site for the biosynthesis of lipids and carbohydrate conjugates, and it is essential for folding, assembly, and biosynthetic transport of secreted proteins and integral membrane proteins. The discovery of abundant membrane contact sites (MCSs) between the ER and other membrane compartments has revealed that, in addition to its biosynthetic and secretory functions, the ER plays key roles in the regulation of organelle dynamics and functions. In this review, we will discuss how the ER regulates endosomes, lysosomes, autophagosomes, mitochondria, peroxisomes, and the Golgi apparatus via MCSs. Such regulation occurs via lipid and Ca2+ transfer and also via control of in trans dephosphorylation reactions and organelle motility, positioning, fusion, and fission. The diverse controls of other organelles via MCSs manifest the ER as master regulator of organelle biology.
Collapse
Affiliation(s)
- Eva Maria Wenzel
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Oslo, Norway 1
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway 2
| | - Liv Anker Elfmark
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Oslo, Norway 1
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway 2
| | - Harald Stenmark
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Oslo, Norway 1
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway 2
| | - Camilla Raiborg
- Centre for Cancer Cell Reprogramming, Faculty of Medicine, University of Oslo, Oslo, Norway 1
- Department of Molecular Cell Biology, Institute for Cancer Research, Oslo University Hospital, Oslo, Norway 2
| |
Collapse
|
5
|
Galvagnion C, Marlet FR, Cerri S, Schapira AHV, Blandini F, Di Monte DA. Sphingolipid changes in Parkinson L444P GBA mutation fibroblasts promote α-synuclein aggregation. Brain 2022; 145:1038-1051. [PMID: 35362022 PMCID: PMC9050548 DOI: 10.1093/brain/awab371] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2020] [Revised: 08/19/2021] [Accepted: 09/06/2021] [Indexed: 12/30/2022] Open
Abstract
Intraneuronal accumulation of aggregated α-synuclein is a pathological hallmark of Parkinson’s disease. Therefore, mechanisms capable of promoting α-synuclein deposition bear important pathogenetic implications. Mutations of the glucocerebrosidase 1 (GBA) gene represent a prevalent Parkinson’s disease risk factor. They are associated with loss of activity of a key enzyme involved in lipid metabolism, glucocerebrosidase, supporting a mechanistic relationship between abnormal α-synuclein–lipid interactions and the development of Parkinson pathology. In this study, the lipid membrane composition of fibroblasts isolated from control subjects, patients with idiopathic Parkinson’s disease and Parkinson's disease patients carrying the L444P GBA mutation (PD-GBA) was assayed using shotgun lipidomics. The lipid profile of PD-GBA fibroblasts differed significantly from that of control and idiopathic Parkinson’s disease cells. It was characterized by an overall increase in sphingolipid levels. It also featured a significant increase in the proportion of ceramide, sphingomyelin and hexosylceramide molecules with shorter chain length and a decrease in the percentage of longer-chain sphingolipids. The extent of this shift was correlated to the degree of reduction of fibroblast glucocerebrosidase activity. Lipid extracts from control and PD-GBA fibroblasts were added to recombinant α-synuclein solutions. The kinetics of α-synuclein aggregation were significantly accelerated after addition of PD-GBA extracts as compared to control samples. Amyloid fibrils collected at the end of these incubations contained lipids, indicating α-synuclein–lipid co-assembly. Lipids extracted from α-synuclein fibrils were also analysed by shotgun lipidomics. Data revealed that the lipid content of these fibrils was significantly enriched by shorter-chain sphingolipids. In a final set of experiments, control and PD-GBA fibroblasts were incubated in the presence of the small molecule chaperone ambroxol. This treatment restored glucocerebrosidase activity and sphingolipid levels and composition of PD-GBA cells. It also reversed the pro-aggregation effect that lipid extracts from PD-GBA fibroblasts had on α-synuclein. Taken together, the findings of this study indicate that the L444P GBA mutation and consequent enzymatic loss are associated with a distinctly altered membrane lipid profile that provides a biological fingerprint of this mutation in Parkinson fibroblasts. This altered lipid profile could also be an indicator of increased risk for α-synuclein aggregate pathology.
Collapse
Affiliation(s)
- Céline Galvagnion
- German Center for Neurodegenerative Diseases (DZNE), 53127 Bonn, Germany.,Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen Ø, Denmark
| | - Frederik Ravnkilde Marlet
- Department of Drug Design and Pharmacology, Faculty of Health and Medical Sciences, University of Copenhagen, 2100 Copenhagen Ø, Denmark
| | - Silvia Cerri
- Cellular and Molecular Neurobiology Unit, IRCCS Mondino Foundation, 27100 Pavia, Italy
| | - Anthony H V Schapira
- Department of Clinical and Movement Neurosciences, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Fabio Blandini
- Cellular and Molecular Neurobiology Unit, IRCCS Mondino Foundation, 27100 Pavia, Italy.,Department of Brain and Behavioral Sciences, University of Pavia, 27100 Pavia, Italy
| | - Donato A Di Monte
- German Center for Neurodegenerative Diseases (DZNE), 53127 Bonn, Germany
| |
Collapse
|
6
|
Kors S, Costello JL, Schrader M. VAP Proteins - From Organelle Tethers to Pathogenic Host Interactors and Their Role in Neuronal Disease. Front Cell Dev Biol 2022; 10:895856. [PMID: 35756994 PMCID: PMC9213790 DOI: 10.3389/fcell.2022.895856] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 04/25/2022] [Indexed: 12/26/2022] Open
Abstract
Vesicle-associated membrane protein (VAMP)-associated proteins (VAPs) are ubiquitous ER-resident tail-anchored membrane proteins in eukaryotic cells. Their N-terminal major sperm protein (MSP) domain faces the cytosol and allows them to interact with a wide variety of cellular proteins. Therefore, VAP proteins are vital to many cellular processes, including organelle membrane tethering, lipid transfer, autophagy, ion homeostasis and viral defence. Here, we provide a timely overview of the increasing number of VAPA/B binding partners and discuss the role of VAPA/B in maintaining organelle-ER interactions and cooperation. Furthermore, we address how viruses and intracellular bacteria hijack VAPs and their binding partners to induce interactions between the host ER and pathogen-containing compartments and support pathogen replication. Finally, we focus on the role of VAP in human disease and discuss how mutated VAPB leads to the disruption of cellular homeostasis and causes amyotrophic lateral sclerosis.
Collapse
Affiliation(s)
- Suzan Kors
- *Correspondence: Suzan Kors, ; Michael Schrader,
| | | | | |
Collapse
|
7
|
Fredriksen K, Aivazidis S, Sharma K, Burbidge KJ, Pitcairn C, Zunke F, Gelyana E, Mazzulli JR. Pathological α-syn aggregation is mediated by glycosphingolipid chain length and the physiological state of α-syn in vivo. Proc Natl Acad Sci U S A 2021; 118:e2108489118. [PMID: 34893541 PMCID: PMC8685670 DOI: 10.1073/pnas.2108489118] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/25/2021] [Indexed: 11/18/2022] Open
Abstract
GBA1 mutations that encode lysosomal β-glucocerebrosidase (GCase) cause the lysosomal storage disorder Gaucher disease (GD) and are strong risk factors for synucleinopathies, including Parkinson's disease and Lewy body dementia. Only a subset of subjects with GBA1 mutations exhibit neurodegeneration, and the factors that influence neurological phenotypes are unknown. We find that α-synuclein (α-syn) neuropathology induced by GCase depletion depends on neuronal maturity, the physiological state of α-syn, and specific accumulation of long-chain glycosphingolipid (GSL) GCase substrates. Reduced GCase activity does not initiate α-syn aggregation in neonatal mice or immature human midbrain cultures; however, adult mice or mature midbrain cultures that express physiological α-syn oligomers are aggregation prone. Accumulation of long-chain GSLs (≥C22), but not short-chain species, induced α-syn pathology and neurological dysfunction. Selective reduction of long-chain GSLs ameliorated α-syn pathology through lysosomal cathepsins. We identify specific requirements that dictate synuclein pathology in GD models, providing possible explanations for the phenotypic variability in subjects with GCase deficiency.
Collapse
Affiliation(s)
- Kristina Fredriksen
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Stefanos Aivazidis
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Karan Sharma
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Kevin J Burbidge
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Caleb Pitcairn
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Friederike Zunke
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen 91054, Germany
| | - Eilrayna Gelyana
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611
| | - Joseph R Mazzulli
- The Ken and Ruth Davee Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611;
| |
Collapse
|
8
|
Ikhlef S, Lipp NF, Delfosse V, Fuggetta N, Bourguet W, Magdeleine M, Drin G. Functional analyses of phosphatidylserine/PI(4)P exchangers with diverse lipid species and membrane contexts reveal unanticipated rules on lipid transfer. BMC Biol 2021; 19:248. [PMID: 34801011 PMCID: PMC8606082 DOI: 10.1186/s12915-021-01183-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 11/04/2021] [Indexed: 11/14/2022] Open
Abstract
Background Lipid species are accurately distributed in the eukaryotic cell so that organelle and plasma membranes have an adequate lipid composition to support numerous cellular functions. In the plasma membrane, a precise regulation of the level of lipids such as phosphatidylserine, PI(4)P, and PI(4,5)P2, is critical for maintaining the signaling competence of the cell. Several lipid transfer proteins of the ORP/Osh family contribute to this fine-tuning by delivering PS, synthesized in the endoplasmic reticulum, to the plasma membrane in exchange for PI(4)P. To get insights into the role of these PS/PI(4)P exchangers in regulating plasma membrane features, we question how they selectively recognize and transfer lipid ligands with different acyl chains, whether these proteins exchange PS exclusively for PI(4)P or additionally for PI(4,5)P2, and how sterol abundance in the plasma membrane impacts their activity. Results We measured in vitro how the yeast Osh6p and human ORP8 transported PS and PI(4)P subspecies of diverse length and unsaturation degree between membranes by fluorescence-based assays. We established that the exchange activity of Osh6p and ORP8 strongly depends on whether these ligands are saturated or not, and is high with representative cellular PS and PI(4)P subspecies. Unexpectedly, we found that the speed at which these proteins individually transfer lipid ligands between membranes is inversely related to their affinity for them and that high-affinity ligands must be exchanged to be transferred more rapidly. Next we determined that Osh6p and ORP8 cannot use PI(4,5)P2 for exchange processes, because it is a low-affinity ligand, and do not transfer more PS into sterol-rich membranes. Conclusions Our study provides new insights into PS/PI(4)P exchangers by indicating the degree to which they can regulate the acyl chain composition of the PM, and how they control PM phosphoinositide levels. Moreover, we establish general rules on how the activity of lipid transfer proteins relates to their affinity for ligands. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-021-01183-1.
Collapse
Affiliation(s)
- Souade Ikhlef
- Université Côte d'Azur, Centre National de la Recherche Scientifique, Institut de Pharmacologie Moléculaire et Cellulaire, 660 route des lucioles, 06560, Valbonne, France
| | - Nicolas-Frédéric Lipp
- Université Côte d'Azur, Centre National de la Recherche Scientifique, Institut de Pharmacologie Moléculaire et Cellulaire, 660 route des lucioles, 06560, Valbonne, France.,Current position: Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA, USA
| | - Vanessa Delfosse
- Centre de Biologie Structurale, INSERM, CNRS, Université de Montpellier, Montpellier, France
| | - Nicolas Fuggetta
- Université Côte d'Azur, Centre National de la Recherche Scientifique, Institut de Pharmacologie Moléculaire et Cellulaire, 660 route des lucioles, 06560, Valbonne, France
| | - William Bourguet
- Centre de Biologie Structurale, INSERM, CNRS, Université de Montpellier, Montpellier, France
| | - Maud Magdeleine
- Université Côte d'Azur, Centre National de la Recherche Scientifique, Institut de Pharmacologie Moléculaire et Cellulaire, 660 route des lucioles, 06560, Valbonne, France
| | - Guillaume Drin
- Université Côte d'Azur, Centre National de la Recherche Scientifique, Institut de Pharmacologie Moléculaire et Cellulaire, 660 route des lucioles, 06560, Valbonne, France.
| |
Collapse
|
9
|
Backman APE, Mattjus P. Who moves the sphinx? An overview of intracellular sphingolipid transport. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1866:159021. [PMID: 34339859 DOI: 10.1016/j.bbalip.2021.159021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 06/24/2021] [Accepted: 06/27/2021] [Indexed: 11/28/2022]
Abstract
Lipid bilayers function as boundaries that enclose their content from the surrounding media, and the composition of different membrane types is accurately and dynamically tailored so that they can perform their function. To achieve this balance, lipid biosynthetic machinery and lipid trafficking events are intertwined into an elegant network. In this review, we focus on the intracellular movement of sphingolipids mediated by sphingolipid transfer proteins. Additionally, we will focus on the best characterized and understood mammalian sphingolipid transfer proteins and provide an overview of how they are hypothesized to function. Some are already well understood, while others remain enigmatic. A few are actual lipid transfer proteins, moving lipids from membrane to membrane, while others may have more of a sensor role, possibly reacting to changes in the concentrations of their ligands. Considering the substrates available for cytosolic sphingolipid transfer proteins, one open question that is discussed is whether galactosylceramide is a target. Another question is the exact mechanics by which sphingolipid transfer proteins are targeted to different organelles, such as how four phosphate adapter protein-2, FAPP2 is targeted to the endoplasmic reticulum. The aim of this review is to discuss what is known within the field today and to provide a basic understanding of how these proteins may work.
Collapse
Affiliation(s)
- Anders P E Backman
- Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland
| | - Peter Mattjus
- Biochemistry, Faculty of Science and Engineering, Åbo Akademi University, Turku, Finland.
| |
Collapse
|
10
|
Li C, Qian T, He R, Wan C, Liu Y, Yu H. Endoplasmic Reticulum-Plasma Membrane Contact Sites: Regulators, Mechanisms, and Physiological Functions. Front Cell Dev Biol 2021; 9:627700. [PMID: 33614657 PMCID: PMC7889955 DOI: 10.3389/fcell.2021.627700] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 01/13/2021] [Indexed: 12/13/2022] Open
Abstract
The endoplasmic reticulum (ER) forms direct membrane contact sites with the plasma membrane (PM) in eukaryotic cells. These ER-PM contact sites play essential roles in lipid homeostasis, ion dynamics, and cell signaling, which are carried out by protein-protein or protein-lipid interactions. Distinct tethering factors dynamically control the architecture of ER-PM junctions in response to intracellular signals or external stimuli. The physiological roles of ER-PM contact sites are dependent on a variety of regulators that individually or cooperatively perform functions in diverse cellular processes. This review focuses on proteins functioning at ER-PM contact sites and highlights the recent progress in their mechanisms and physiological roles.
Collapse
Affiliation(s)
- Chenlu Li
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Tiantian Qian
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Ruyue He
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Chun Wan
- Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, CO, United States
| | - Yinghui Liu
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Haijia Yu
- Jiangsu Key Laboratory for Molecular and Medical Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| |
Collapse
|
11
|
Mishra SK, Gao YG, Zou X, Stephenson DJ, Malinina L, Hinchcliffe EH, Chalfant CE, Brown RE. Emerging roles for human glycolipid transfer protein superfamily members in the regulation of autophagy, inflammation, and cell death. Prog Lipid Res 2020; 78:101031. [PMID: 32339554 DOI: 10.1016/j.plipres.2020.101031] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 02/27/2020] [Accepted: 02/27/2020] [Indexed: 12/14/2022]
Abstract
Glycolipid transfer proteins (GLTPs) were first identified over three decades ago as ~24kDa, soluble, amphitropic proteins that specifically accelerate the intermembrane transfer of glycolipids. Upon discovery that GLTPs use a unique, all-α-helical, two-layer 'sandwich' architecture (GLTP-fold) to bind glycosphingolipids (GSLs), a new protein superfamily was born. Structure/function studies have provided exquisite insights defining features responsible for lipid headgroup selectivity and hydrophobic 'pocket' adaptability for accommodating hydrocarbon chains of differing length and unsaturation. In humans, evolutionarily-modified GLTP-folds have been identified with altered sphingolipid specificity, e. g. ceramide-1-phosphate transfer protein (CPTP), phosphatidylinositol 4-phosphate adaptor protein-2 (FAPP2) which harbors a GLTP-domain and GLTPD2. Despite the wealth of structural data (>40 Protein Data Bank deposits), insights into the in vivo functional roles of GLTP superfamily members have emerged slowly. In this review, recent advances are presented and discussed implicating human GLTP superfamily members as important regulators of: i) pro-inflammatory eicosanoid production associated with Group-IV cytoplasmic phospholipase A2; ii) autophagy and inflammasome assembly that drive surveillance cell release of interleukin-1β and interleukin-18 inflammatory cytokines; iii) cell cycle arrest and necroptosis induction in certain colon cancer cell lines. The effects exerted by GLTP superfamily members appear linked to their ability to regulate sphingolipid homeostasis by acting in either transporter and/or sensor capacities. These timely findings are opening new avenues for future cross-disciplinary, translational medical research involving GLTP-fold proteins in human health and disease. Such avenues include targeted regulation of specific GLTP superfamily members to alter sphingolipid levels as a therapeutic means for combating viral infection, neurodegenerative conditions and circumventing chemo-resistance during cancer treatment.
Collapse
Affiliation(s)
- Shrawan K Mishra
- Hormel Institute, University of Minnesota, Austin, MN 55912, USA
| | - Yong-Guang Gao
- Hormel Institute, University of Minnesota, Austin, MN 55912, USA
| | - Xianqiong Zou
- Hormel Institute, University of Minnesota, Austin, MN 55912, USA
| | - Daniel J Stephenson
- Department of Biochemistry and Molecular Biology, Virginia Commonwealth University Medical Center, Richmond, VA 23298-0614, USA; Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL 33620, USA
| | - Lucy Malinina
- Hormel Institute, University of Minnesota, Austin, MN 55912, USA
| | | | - Charles E Chalfant
- Department of Cell Biology, Microbiology and Molecular Biology, University of South Florida, Tampa, FL 33620, USA; Research Service, James A. Haley Veterans Hospital, Tampa, FL 33612, USA; The Moffitt Cancer Center, Tampa, FL 33620, USA
| | | |
Collapse
|