1
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Tian L, Andrews C, Yan Q, Yang JJ. Molecular regulation of calcium-sensing receptor (CaSR)-mediated signaling. Chronic Dis Transl Med 2024; 10:167-194. [PMID: 39027195 PMCID: PMC11252437 DOI: 10.1002/cdt3.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2024] [Revised: 03/29/2024] [Accepted: 04/09/2024] [Indexed: 07/20/2024] Open
Abstract
Calcium-sensing receptor (CaSR), a family C G-protein-coupled receptor, plays a crucial role in regulating calcium homeostasis by sensing small concentration changes of extracellular Ca2+, Mg2+, amino acids (e.g., L-Trp and L-Phe), small peptides, anions (e.g., HCO3 - and PO4 3-), and pH. CaSR-mediated intracellular Ca2+ signaling regulates a diverse set of cellular processes including gene transcription, cell proliferation, differentiation, apoptosis, muscle contraction, and neuronal transmission. Dysfunction of CaSR with mutations results in diseases such as autosomal dominant hypocalcemia, familial hypocalciuric hypercalcemia, and neonatal severe hyperparathyroidism. CaSR also influences calciotropic disorders, such as osteoporosis, and noncalciotropic disorders, such as cancer, Alzheimer's disease, and pulmonary arterial hypertension. This study first reviews recent advances in biochemical and structural determination of the framework of CaSR and its interaction sites with natural ligands, as well as exogenous positive allosteric modulators and negative allosteric modulators. The establishment of the first CaSR protein-protein interactome network revealed 94 novel players involved in protein processing in endoplasmic reticulum, trafficking, cell surface expression, endocytosis, degradation, and signaling pathways. The roles of these proteins in Ca2+-dependent cellular physiological processes and in CaSR-dependent cellular signaling provide new insights into the molecular basis of diseases caused by CaSR mutations and dysregulated CaSR activity caused by its protein interactors and facilitate the design of therapeutic agents that target CaSR and other family C G-protein-coupled receptors.
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Affiliation(s)
- Li Tian
- Department of Chemistry, Center for Diagnostics and Therapeutics, Advanced Translational Imaging FacilityGeorgia State UniversityAtlantaGeorgiaUSA
| | - Corey Andrews
- Department of Chemistry, Center for Diagnostics and Therapeutics, Advanced Translational Imaging FacilityGeorgia State UniversityAtlantaGeorgiaUSA
| | - Qiuyun Yan
- Department of Chemistry, Center for Diagnostics and Therapeutics, Advanced Translational Imaging FacilityGeorgia State UniversityAtlantaGeorgiaUSA
| | - Jenny J. Yang
- Department of Chemistry, Center for Diagnostics and Therapeutics, Advanced Translational Imaging FacilityGeorgia State UniversityAtlantaGeorgiaUSA
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2
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Renna L, Stefano G, Puggioni MP, Kim SJ, Lavell A, Froehlich JE, Burkart G, Mancuso S, Benning C, Brandizzi F. ER-associated VAP27-1 and VAP27-3 proteins functionally link the lipid-binding ORP2A at the ER-chloroplast contact sites. Nat Commun 2024; 15:6008. [PMID: 39019917 PMCID: PMC11255254 DOI: 10.1038/s41467-024-50425-7] [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: 12/01/2022] [Accepted: 07/09/2024] [Indexed: 07/19/2024] Open
Abstract
The plant endoplasmic reticulum (ER) contacts heterotypic membranes at membrane contact sites (MCSs) through largely undefined mechanisms. For instance, despite the well-established and essential role of the plant ER-chloroplast interactions for lipid biosynthesis, and the reported existence of physical contacts between these organelles, almost nothing is known about the ER-chloroplast MCS identity. Here we show that the Arabidopsis ER membrane-associated VAP27 proteins and the lipid-binding protein ORP2A define a functional complex at the ER-chloroplast MCSs. Specifically, through in vivo and in vitro association assays, we found that VAP27 proteins interact with the outer envelope membrane (OEM) of chloroplasts, where they bind to ORP2A. Through lipidomic analyses, we established that VAP27 proteins and ORP2A directly interact with the chloroplast OEM monogalactosyldiacylglycerol (MGDG), and we demonstrated that the loss of the VAP27-ORP2A complex is accompanied by subtle changes in the acyl composition of MGDG and PG. We also found that ORP2A interacts with phytosterols and established that the loss of the VAP27-ORP2A complex alters sterol levels in chloroplasts. We propose that, by interacting directly with OEM lipids, the VAP27-ORP2A complex defines plant-unique MCSs that bridge ER and chloroplasts and are involved in chloroplast lipid homeostasis.
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Affiliation(s)
- Luciana Renna
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, MI, USA
- Department of Horticulture, University of Florence, Florence, Italy
| | - Giovanni Stefano
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, MI, USA
- Department of Plant Biology, Michigan State University, East Lansing, MI, USA
- Department of Biology, University of Florence, Florence, Italy
| | - Maria Paola Puggioni
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, MI, USA
- Department of Plant Physiology, Umeå Plant Science Centre, Umeå University, Umeå, Sweden
| | - Sang-Jin Kim
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, MI, USA
- Department of Plant Biology, Michigan State University, East Lansing, MI, USA
- Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI, USA
| | - Anastasiya Lavell
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, MI, USA
| | - John E Froehlich
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, MI, USA
- Biochemistry and Molecular Biology Department, Michigan State University, East Lansing, MI, USA
| | - Graham Burkart
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, MI, USA
| | - Stefano Mancuso
- Department of Horticulture, University of Florence, Florence, Italy
- Fondazione per il Futuro delle Città, Florence, Italy
| | - Christoph Benning
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, MI, USA
- Department of Plant Biology, Michigan State University, East Lansing, MI, USA
- Biochemistry and Molecular Biology Department, Michigan State University, East Lansing, MI, USA
| | - Federica Brandizzi
- MSU-DOE Plant Research Lab, Michigan State University, East Lansing, MI, USA.
- Department of Plant Biology, Michigan State University, East Lansing, MI, USA.
- Great Lakes Bioenergy Research Center, Michigan State University, East Lansing, MI, USA.
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3
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Wang Y, Yang J. ER-organelle contacts: A signaling hub for neurological diseases. Pharmacol Res 2024; 203:107149. [PMID: 38518830 DOI: 10.1016/j.phrs.2024.107149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 03/07/2024] [Accepted: 03/19/2024] [Indexed: 03/24/2024]
Abstract
Neuronal health is closely linked to the homeostasis of intracellular organelles, and organelle dysfunction affects the pathological progression of neurological diseases. In contrast to isolated cellular compartments, a growing number of studies have found that organelles are largely interdependent structures capable of communicating through membrane contact sites (MCSs). MCSs have been identified as key pathways mediating inter-organelle communication crosstalk in neurons, and their alterations have been linked to neurological disease pathology. The endoplasmic reticulum (ER) is a membrane-bound organelle capable of forming an extensive network of pools and tubules with important physiological functions within neurons. There are multiple MCSs between the ER and other organelles and the plasma membrane (PM), which regulate a variety of cellular processes. In this review, we focus on ER-organelle MCSs and their role in a variety of neurological diseases. We compared the biological effects between different tethering proteins and the effects of their respective disease counterparts. We also discuss how altered ER-organelle contacts may affect disease pathogenesis. Therefore, understanding the molecular mechanisms of ER-organelle MCSs in neuronal homeostasis will lay the foundation for the development of new therapies targeting ER-organelle contacts.
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Affiliation(s)
- Yunli Wang
- Key Laboratory of Environmental Stress and Chronic Disease Control & Prevention (China Medical University), Ministry of Education, PR China; Department of Toxicology, School of Public Health, China Medical University, Shenyang 110122, PR China
| | - Jinghua Yang
- Key Laboratory of Environmental Stress and Chronic Disease Control & Prevention (China Medical University), Ministry of Education, PR China; Department of Toxicology, School of Public Health, China Medical University, Shenyang 110122, PR China.
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4
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Cockcroft S. The expanding roles of PI4P and PI(4,5)P 2 at the plasma membrane: Role of phosphatidylinositol transfer proteins. Biochim Biophys Acta Mol Cell Biol Lipids 2024; 1869:159394. [PMID: 37714261 DOI: 10.1016/j.bbalip.2023.159394] [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: 07/19/2023] [Revised: 08/31/2023] [Accepted: 09/05/2023] [Indexed: 09/17/2023]
Abstract
Phosphoinositides are phosphorylated derivatives of phosphatidylinositol, a phospholipid that is synthesised at the endoplasmic reticulum. The plasma membrane contains the enzymes to phosphorylate phosphatidylinositol and is therefore rich in the phosphorylated derivatives, PI4P and PI(4,5)P2. PI(4,5)P2 is a substrate for phospholipase C and during cell signaling, PI(4,5)P2 levels are reduced. Here I discuss a family of proteins, phosphatidylinositol transfer proteins (PITPs) that can restore PI(4,5)P2 levels.
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Affiliation(s)
- Shamshad Cockcroft
- Department of Neuroscience, Physiology and Pharmacology, Division of Biosciences, University College London, 21 University Street, London WC1E 6JJ, UK.
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5
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Saha S, Krishnan H, Raghu P. IMPA1 dependent regulation of phosphatidylinositol 4,5-bisphosphate and calcium signalling by lithium. Life Sci Alliance 2024; 7:e202302425. [PMID: 38056909 PMCID: PMC10700560 DOI: 10.26508/lsa.202302425] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 11/22/2023] [Accepted: 11/27/2023] [Indexed: 12/08/2023] Open
Abstract
Lithium (Li) is widely used as a mood stabilizer to treat bipolar affective disorder. However, the molecular targets of Li that underpin its therapeutic effect remain unresolved. Inositol monophosphatase (IMPA1) is an enzyme involved in phosphatidylinositol 4,5-bisphosphate (PIP2) resynthesis after PLC signaling. In vitro, Li inhibits IMPA1, but the relevance of this inhibition within neural cells remains unknown. Here, we report that treatment with therapeutic concentrations of Li reduces receptor-activated calcium release from intracellular stores and delays PIP2 resynthesis. These effects of Li are abrogated in IMPA1 deleted cells. We also observed that in human forebrain cortical neurons, treatment with Li reduced neuronal excitability and calcium signals. After Li treatment of human cortical neurons, transcriptome analyses revealed down-regulation of signaling by glutamate, a key excitatory neurotransmitter in the human brain. Collectively, our findings suggest that inhibition of IMPA1 by Li reduces receptor-activated PLC signaling and neuronal excitability.
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Affiliation(s)
- Sankhanil Saha
- https://ror.org/03gf8rp76 National Centre for Biological Sciences-TIFR GKVK Campus, Bangalore, India
| | - Harini Krishnan
- https://ror.org/03gf8rp76 National Centre for Biological Sciences-TIFR GKVK Campus, Bangalore, India
| | - Padinjat Raghu
- https://ror.org/03gf8rp76 National Centre for Biological Sciences-TIFR GKVK Campus, Bangalore, India
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6
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Traczyk G, Hromada-Judycka A, Świątkowska A, Wiśniewska J, Ciesielska A, Kwiatkowska K. Diacylglycerol kinase-ε is S-palmitoylated on cysteine in the cytoplasmic end of its N-terminal transmembrane fragment. J Lipid Res 2024; 65:100480. [PMID: 38008259 PMCID: PMC10759177 DOI: 10.1016/j.jlr.2023.100480] [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: 03/30/2023] [Revised: 11/17/2023] [Accepted: 11/18/2023] [Indexed: 11/28/2023] Open
Abstract
Diacylglycerol kinase-ε (DGKε) catalyzes phosphorylation of diacylglycerol to phosphatidic acid with a unique specificity toward 1-stearoyl-2-arachidonoyl-sn-glycerol, which is a backbone of phosphatidylinositol (PI). Owing to this specificity, DGKε is involved in the PI cycle maintaining the cellular level of phosphorylated PI derivatives of signaling activity and was also found crucial for lipid metabolism. DGKε dysfunction is linked with the development of atypical hemolytic uremic syndrome (aHUS) and possibly other human diseases. Despite the DGKε significance, data on its regulation by cotranslational and/or post-translational modifications are scarce. Here, we report that DGKε is S-palmitoylated at Cys38/40 (mouse/human DGKε) located in the cytoplasmic end of its N-terminal putative transmembrane fragment. The S-palmitoylation of DGKε was revealed by metabolic labeling of cells with a palmitic acid analogue followed by click chemistry and with acyl-biotin and acyl-polyethylene glycol exchange assays. The S-acyltransferases zDHHC7 (zinc finger DHHC domain containing) and zDHHC17 and the zDHHC6/16 tandem were found to catalyze DGKε S-palmitoylation, which also increased the DGKε abundance. Mouse DGKε-Myc ectopically expressed in human embryonic kidney 293 cells localized to the endoplasmic reticulum where zDHHC6/16 reside and in small amounts also to the Golgi apparatus where zDHHC7 and zDHHC17 are present. The Cys38Ala substitution upregulated, whereas hyperpalmitoylation of wild-type DGKε reduced the kinase activity, indicating an inhibitory effect of the Cys38 S-palmitoylation. In addition, the substitution of neighboring Pro31 with Ala also diminished the activity of DGKε. Taken together, our data indicate that S-palmitoylation can fine-tune DGKε activity in distinct cellular compartments, possibly by affecting the distance between the kinase and its substrate in a membrane.
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Affiliation(s)
- Gabriela Traczyk
- Laboratory of Molecular Membrane Biology, Nencki Institute of Experimental Biology PAS, Warsaw, Poland
| | - Aneta Hromada-Judycka
- Laboratory of Molecular Membrane Biology, Nencki Institute of Experimental Biology PAS, Warsaw, Poland
| | - Anna Świątkowska
- Laboratory of Molecular Membrane Biology, Nencki Institute of Experimental Biology PAS, Warsaw, Poland
| | - Julia Wiśniewska
- Laboratory of Molecular Membrane Biology, Nencki Institute of Experimental Biology PAS, Warsaw, Poland
| | - Anna Ciesielska
- Laboratory of Molecular Membrane Biology, Nencki Institute of Experimental Biology PAS, Warsaw, Poland
| | - Katarzyna Kwiatkowska
- Laboratory of Molecular Membrane Biology, Nencki Institute of Experimental Biology PAS, Warsaw, Poland.
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7
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Allaire P, He J, Mayer J, Moat L, Gerstenberger P, Wilhorn R, Strutz S, Kim DS, Zeng C, Cox N, Shay JW, Denny J, Bastarache L, Hebbring S. Genetic and clinical determinants of telomere length. HGG ADVANCES 2023; 4:100201. [PMID: 37216007 PMCID: PMC10199259 DOI: 10.1016/j.xhgg.2023.100201] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 04/21/2023] [Indexed: 05/24/2023] Open
Abstract
Many epidemiologic studies have identified important relationships between leukocyte telomere length (LTL) with genetics and health. Most of these studies have been significantly limited in scope by focusing predominantly on individual diseases or restricted to GWAS analysis. Using two large patient populations derived from Vanderbilt University and Marshfield Clinic biobanks linked to genomic and phenomic data from medical records, we investigated the inter-relationship between LTL, genomics, and human health. Our GWAS confirmed 11 genetic loci previously associated with LTL and two novel loci in SCNN1D and PITPNM1. PheWAS of LTL identified 67 distinct clinical phenotypes associated with both short and long LTL. We demonstrated that several diseases associated with LTL were related to one another but were largely independent from LTL genetics. Age of death was correlated with LTL independent of age. Those with very short LTL (<-1.5 standard deviation [SD]) died 10.4 years (p < 0.0001) younger than those with average LTL (±0.5 SD; mean age of death = 74.2 years). Likewise, those with very long LTL (>1.5 SD) died 1.9 years (p = 0.0175) younger than those with average LTL. This is consistent with the PheWAS results showing diseases associating with both short and long LTL. Finally, we estimated that the genome (12.8%) and age (8.5%) explain the largest proportion of LTL variance, whereas the phenome (1.5%) and sex (0.9%) explained a smaller fraction. In total, 23.7% of LTL variance was explained. These observations provide the rationale for expanded research to understand the multifaceted correlations between TL biology and human health over time, leading to effective LTL usage in medical applications.
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Affiliation(s)
- Patrick Allaire
- Marshfield Clinic Research Institute, Center for Precision Medicine Research, Marshfield, WI, USA
| | - Jing He
- Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - John Mayer
- Marshfield Clinic Research Institute, Office of Research Computing and Analytics, Marshfield, WI, USA
| | - Luke Moat
- Marshfield Clinic Research Institute, Center for Precision Medicine Research, Marshfield, WI, USA
| | - Peter Gerstenberger
- Marshfield Clinic Research Institute, Center for Precision Medicine Research, Marshfield, WI, USA
| | - Reynor Wilhorn
- Marshfield Clinic Research Institute, Center for Precision Medicine Research, Marshfield, WI, USA
| | - Sierra Strutz
- Marshfield Clinic Research Institute, Center for Precision Medicine Research, Marshfield, WI, USA
| | - David S.L. Kim
- Marshfield Clinic Health System, Pathology, Marshfield, WI, USA
| | - Chenjie Zeng
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Nancy Cox
- Vanderbilt Genetics Institute, Division of Genetic Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Jerry W. Shay
- University of Texas Southwestern Medical Center, Department of Cell Biology and the Simmons Comprehensive Cancer Center, Dallas, TX, USA
| | - Joshua Denny
- National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA
| | - Lisa Bastarache
- Center for Precision Medicine, Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Scott Hebbring
- Marshfield Clinic Research Institute, Center for Precision Medicine Research, Marshfield, WI, USA
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8
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Jensen JB, Falkenburger BH, Dickson EJ, de la Cruz L, Dai G, Myeong J, Jung SR, Kruse M, Vivas O, Suh BC, Hille B. Biophysical physiology of phosphoinositide rapid dynamics and regulation in living cells. J Gen Physiol 2022; 154:e202113074. [PMID: 35583815 PMCID: PMC9121023 DOI: 10.1085/jgp.202113074] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 04/28/2022] [Indexed: 01/07/2023] Open
Abstract
Phosphoinositide membrane lipids are ubiquitous low-abundance signaling molecules. They direct many physiological processes that involve ion channels, membrane identification, fusion of membrane vesicles, and vesicular endocytosis. Pools of these lipids are continually broken down and refilled in living cells, and the rates of some of these reactions are strongly accelerated by physiological stimuli. Recent biophysical experiments described here measure and model the kinetics and regulation of these lipid signals in intact cells. Rapid on-line monitoring of phosphoinositide metabolism is made possible by optical tools and electrophysiology. The experiments reviewed here reveal that as for other cellular second messengers, the dynamic turnover and lifetimes of membrane phosphoinositides are measured in seconds, controlling and timing rapid physiological responses, and the signaling is under strong metabolic regulation. The underlying mechanisms of this metabolic regulation remain questions for the future.
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Affiliation(s)
- Jill B. Jensen
- Department of Physiology and Biophysics, University of Washington, Seattle, WA
| | | | - Eamonn J. Dickson
- Department of Physiology and Membrane Biology, University of California, Davis, Davis, CA
| | - Lizbeth de la Cruz
- Department of Physiology and Biophysics, University of Washington, Seattle, WA
| | - Gucan Dai
- Department of Biochemistry and Molecular Biology, Saint Louis University School of Medicine, St. Louis, MO
| | - Jongyun Myeong
- Department of Cell Biology and Physiology, Washington University in St. Louis, St. Louis, MO
| | | | - Martin Kruse
- Department of Biology and Program in Neuroscience, Bates College, Lewiston, ME
| | - Oscar Vivas
- Department of Physiology and Biophysics, University of Washington, Seattle, WA
| | - Byung-Chang Suh
- Department of Brain Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Republic of Korea
| | - Bertil Hille
- Department of Physiology and Biophysics, University of Washington, Seattle, WA
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9
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Ventura R, Martínez-Ruiz I, Hernández-Alvarez MI. Phospholipid Membrane Transport and Associated Diseases. Biomedicines 2022; 10:biomedicines10051201. [PMID: 35625937 PMCID: PMC9138374 DOI: 10.3390/biomedicines10051201] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 05/19/2022] [Accepted: 05/20/2022] [Indexed: 11/16/2022] Open
Abstract
Phospholipids are the basic structure block of eukaryotic membranes, in both the outer and inner membranes, which delimit cell organelles. Phospholipids can also be damaged by oxidative stress produced by mitochondria, for instance, becoming oxidized phospholipids. These damaged phospholipids have been related to prevalent diseases such as atherosclerosis or non-alcoholic steatohepatitis (NASH) because they alter gene expression and induce cellular stress and apoptosis. One of the main sites of phospholipid synthesis is the endoplasmic reticulum (ER). ER association with other organelles through membrane contact sites (MCS) provides a close apposition for lipid transport. Additionally, an important advance in this small cytosolic gap are lipid transfer proteins (LTPs), which accelerate and modulate the distribution of phospholipids in other organelles. In this regard, LTPs can be established as an essential point within phospholipid circulation, as relevant data show impaired phospholipid transport when LTPs are defected. This review will focus on phospholipid function, metabolism, non-vesicular transport, and associated diseases.
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Affiliation(s)
- Raúl Ventura
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, 08028 Barcelona, Spain; (R.V.); (I.M.-R.)
| | - Inma Martínez-Ruiz
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, 08028 Barcelona, Spain; (R.V.); (I.M.-R.)
| | - María Isabel Hernández-Alvarez
- Departament de Bioquímica i Biomedicina Molecular, Facultat de Biologia, Universitat de Barcelona, 08028 Barcelona, Spain; (R.V.); (I.M.-R.)
- Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Instituto de Salud Carlos III, 28029 Madrid, Spain
- IBUB Universitat de Barcelona—Institut de Biomedicina de la Universitat de Barcelona, 08028 Barcelona, Spain
- Correspondence:
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10
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Jamecna D, Antonny B. Intrinsically disordered protein regions at membrane contact sites. Biochim Biophys Acta Mol Cell Biol Lipids 2021; 1866:159020. [PMID: 34352388 DOI: 10.1016/j.bbalip.2021.159020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 06/30/2021] [Accepted: 07/01/2021] [Indexed: 12/14/2022]
Abstract
Membrane contact sites (MCS) are regions of close apposition between membrane-bound organelles. Proteins that occupy MCS display various domain organisation. Among them, lipid transfer proteins (LTPs) frequently contain both structured domains as well as regions of intrinsic disorder. In this review, we discuss the various roles of intrinsically disordered protein regions (IDPRs) in LTPs as well as in other proteins that are associated with organelle contact sites. We distinguish the following functions: (i) to act as flexible tethers between two membranes; (ii) to act as entropic barriers to prevent protein crowding and regulate membrane tethering geometry; (iii) to define the action range of catalytic domains. These functions are added to other functions of IDPRs in membrane environments, such as mediating protein-protein and protein-membrane interactions. We suggest that the overall efficiency and fidelity of contact sites might require fine coordination between all these IDPR activities.
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Affiliation(s)
- Denisa Jamecna
- Université Côte d'Azur et CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, 660 route des lucioles, 06560 Valbonne, France; Biochemistry Center (BZH), Heidelberg, Germany
| | - Bruno Antonny
- Université Côte d'Azur et CNRS, Institut de Pharmacologie Moléculaire et Cellulaire, 660 route des lucioles, 06560 Valbonne, France.
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11
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James C, Kehlenbach RH. The Interactome of the VAP Family of Proteins: An Overview. Cells 2021; 10:cells10071780. [PMID: 34359948 PMCID: PMC8306308 DOI: 10.3390/cells10071780] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Revised: 06/28/2021] [Accepted: 07/08/2021] [Indexed: 12/11/2022] Open
Abstract
Membrane contact sites (MCS) are sites of close apposition of two organelles that help in lipid transport and synthesis, calcium homeostasis and several other biological processes. The VAMP-associated proteins (VAPs) VAPA, VAPB, MOSPD2 and the recently described MOSPD1 and MOSPD3 are tether proteins of MCSs that are mainly found at the endoplasmic reticulum (ER). VAPs interact with various proteins with a motif called FFAT (two phenylalanines in an acidic tract), recruiting the associated organelle to the ER. In addition to the conventional FFAT motif, the recently described FFNT (two phenylalanines in a neutral tract) and phospho-FFAT motifs contribute to the interaction with VAPs. In this review, we summarize and compare the recent interactome studies described for VAPs, including in silico and proximity labeling methods. Collectively, the interaction repertoire of VAPs is very diverse and highlights the complexity of interactions mediated by the different FFAT motifs to the VAPs.
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12
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Tábara LC, Morris JL, Prudent J. The Complex Dance of Organelles during Mitochondrial Division. Trends Cell Biol 2021; 31:241-253. [PMID: 33446409 DOI: 10.1016/j.tcb.2020.12.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 11/28/2020] [Accepted: 12/07/2020] [Indexed: 12/17/2022]
Abstract
Mitochondria are dynamic organelles that undergo cycles of fission and fusion events depending on cellular requirements. During mitochondrial division, the GTPase dynamin-related protein-1 is recruited to endoplasmic reticulum (ER)-induced mitochondrial constriction sites where it drives fission. However, the events required to complete scission of mitochondrial membranes are not well understood. Here, we emphasize the recently described roles for Golgi-derived phosphatidylinositol 4-phosphate (PI4P)-containing vesicles in the last steps of mitochondrial division. We then propose how trans-Golgi network vesicles at mitochondria-ER contact sites and PI4P generation could mechanistically execute mitochondrial division, by recruiting PI4P effectors and/or the actin nucleation machinery. Finally, we speculate on mechanisms to explain why such a complex dance of different organelles is required to facilitate the remodelling of mitochondrial membranes.
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Affiliation(s)
- Luis-Carlos Tábara
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Jordan L Morris
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Julien Prudent
- Medical Research Council Mitochondrial Biology Unit, University of Cambridge, The Keith Peters Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK.
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13
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Lete MG, Tripathi A, Chandran V, Bankaitis VA, McDermott MI. Lipid transfer proteins and instructive regulation of lipid kinase activities: Implications for inositol lipid signaling and disease. Adv Biol Regul 2020; 78:100740. [PMID: 32992233 PMCID: PMC7986245 DOI: 10.1016/j.jbior.2020.100740] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Revised: 06/16/2020] [Accepted: 06/24/2020] [Indexed: 05/17/2023]
Abstract
Cellular membranes are critical platforms for intracellular signaling that involve complex interfaces between lipids and proteins, and a web of interactions between a multitude of lipid metabolic pathways. Membrane lipids impart structural and functional information in this regulatory circuit that encompass biophysical parameters such as membrane thickness and fluidity, as well as chaperoning the interactions of protein binding partners. Phosphatidylinositol and its phosphorylated derivatives, the phosphoinositides, play key roles in intracellular membrane signaling, and these involvements are translated into an impressively diverse set of biological outcomes. The phosphatidylinositol transfer proteins (PITPs) are key regulators of phosphoinositide signaling. Found in a diverse array of organisms from plants, yeast and apicomplexan parasites to mammals, PITPs were initially proposed to be simple transporters of lipids between intracellular membranes. It now appears increasingly unlikely that the soluble versions of these proteins perform such functions within the cell. Rather, these serve to facilitate the activity of intrinsically biologically insufficient inositol lipid kinases and, in so doing, promote diversification of the biological outcomes of phosphoinositide signaling. The central engine for execution of such functions is the lipid exchange cycle that is a fundamental property of PITPs. How PITPs execute lipid exchange remains very poorly understood. Molecular dynamics simulation approaches are now providing the first atomistic insights into how PITPs, and potentially other lipid-exchange/transfer proteins, operate.
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Affiliation(s)
- Marta G Lete
- Department of Molecular and Cellular Medicine, Texas A&M Health Sciences Center, College Station, TX, 77843-1114, USA; Institute Biofisika (UPV/EHU, CSIC) and University of the Basque Country, Leioa, Spain
| | - Ashutosh Tripathi
- Department of Molecular and Cellular Medicine, Texas A&M Health Sciences Center, College Station, TX, 77843-1114, USA
| | - Vijay Chandran
- Department of Molecular and Cellular Medicine, Texas A&M Health Sciences Center, College Station, TX, 77843-1114, USA
| | - Vytas A Bankaitis
- Department of Molecular and Cellular Medicine, Texas A&M Health Sciences Center, College Station, TX, 77843-1114, USA; Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX, 77843-2128, USA; Department of Chemistry, Texas A&M University, College Station, TX, 77840, USA
| | - Mark I McDermott
- Department of Molecular and Cellular Medicine, Texas A&M Health Sciences Center, College Station, TX, 77843-1114, USA.
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14
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Katan M, Cockcroft S. Phosphatidylinositol(4,5)bisphosphate: diverse functions at the plasma membrane. Essays Biochem 2020; 64:513-531. [PMID: 32844214 PMCID: PMC7517351 DOI: 10.1042/ebc20200041] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 07/25/2020] [Accepted: 07/29/2020] [Indexed: 12/20/2022]
Abstract
Phosphatidylinositol(4,5) bisphosphate (PI(4,5)P2) has become a major focus in biochemistry, cell biology and physiology owing to its diverse functions at the plasma membrane. As a result, the functions of PI(4,5)P2 can be explored in two separate and distinct roles - as a substrate for phospholipase C (PLC) and phosphoinositide 3-kinase (PI3K) and as a primary messenger, each having unique properties. Thus PI(4,5)P2 makes contributions in both signal transduction and cellular processes including actin cytoskeleton dynamics, membrane dynamics and ion channel regulation. Signalling through plasma membrane G-protein coupled receptors (GPCRs), receptor tyrosine kinases (RTKs) and immune receptors all use PI(4,5)P2 as a substrate to make second messengers. Activation of PI3K generates PI(3,4,5)P3 (phosphatidylinositol(3,4,5)trisphosphate), a lipid that recruits a plethora of proteins with pleckstrin homology (PH) domains to the plasma membrane to regulate multiple aspects of cellular function. In contrast, PLC activation results in the hydrolysis of PI(4,5)P2 to generate the second messengers, diacylglycerol (DAG), an activator of protein kinase C and inositol(1,4,5)trisphosphate (IP3/I(1,4,5)P3) which facilitates an increase in intracellular Ca2+. Decreases in PI(4,5)P2 by PLC also impact on functions that are dependent on the intact lipid and therefore endocytosis, actin dynamics and ion channel regulation are subject to control. Spatial organisation of PI(4,5)P2 in nanodomains at the membrane allows for these multiple processes to occur concurrently.
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Affiliation(s)
- Matilda Katan
- Institute of Structural and Molecular Biology, Division of Biosciences, University College London, Gower Street, London WC1E 6BT, U.K
| | - Shamshad Cockcroft
- Department of Neuroscience, Physiology and Pharmacology, Division of Biosciences, University College London, 21 University Street, London WC1E 6JJ, U.K
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15
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Li W, Zhang S, Yang G. Dynamic organization of intracellular organelle networks. WIREs Mech Dis 2020; 13:e1505. [PMID: 32865347 DOI: 10.1002/wsbm.1505] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Revised: 06/06/2020] [Accepted: 07/09/2020] [Indexed: 01/07/2023]
Abstract
Intracellular organelles are membrane-bound and biochemically distinct compartments constructed to serve specialized functions in eukaryotic cells. Through extensive interactions, they form networks to coordinate and integrate their specialized functions for cell physiology. A fundamental property of these organelle networks is that they constantly undergo dynamic organization via membrane fusion and fission to remodel their internal connections and to mediate direct material exchange between compartments. The dynamic organization not only enables them to serve critical physiological functions adaptively but also differentiates them from many other biological networks such as gene regulatory networks and cell signaling networks. This review examines this fundamental property of the organelle networks from a systems point of view. The focus is exclusively on homotypic networks formed by mitochondria, lysosomes, endosomes, and the endoplasmic reticulum, respectively. First, key mechanisms that drive the dynamic organization of these networks are summarized. Then, several distinct organizational properties of these networks are highlighted. Next, spatial properties of the dynamic organization of these networks are emphasized, and their functional implications are examined. Finally, some representative molecular machineries that mediate the dynamic organization of these networks are surveyed. Overall, the dynamic organization of intracellular organelle networks is emerging as a fundamental and unifying paradigm in the internal organization of eukaryotic cells. This article is categorized under: Metabolic Diseases > Molecular and Cellular Physiology.
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Affiliation(s)
- Wenjing Li
- Laboratory of Computational Biology and Machine Intelligence, School of Artificial Intelligence, University of Chinese Academy of Sciences, Beijing, China.,National Laboratory of Pattern Recognition, Institute of Automation, Chinese Academy of Sciences, Beijing, China
| | - Shuhao Zhang
- Laboratory of Computational Biology and Machine Intelligence, School of Artificial Intelligence, University of Chinese Academy of Sciences, Beijing, China.,National Laboratory of Pattern Recognition, Institute of Automation, Chinese Academy of Sciences, Beijing, China.,College of Life Sciences, Nankai University, Tianjin, China
| | - Ge Yang
- Laboratory of Computational Biology and Machine Intelligence, School of Artificial Intelligence, University of Chinese Academy of Sciences, Beijing, China.,National Laboratory of Pattern Recognition, Institute of Automation, Chinese Academy of Sciences, Beijing, China.,Department of Biomedical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA.,Department of Computational Biology, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
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16
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Kirmiz M, Gillies TE, Dickson EJ, Trimmer JS. Neuronal ER-plasma membrane junctions organized by Kv2-VAP pairing recruit Nir proteins and affect phosphoinositide homeostasis. J Biol Chem 2019; 294:17735-17757. [PMID: 31594866 DOI: 10.1074/jbc.ra119.007635] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 10/02/2019] [Indexed: 12/21/2022] Open
Abstract
The association of plasma membrane (PM)-localized voltage-gated potassium (Kv2) channels with endoplasmic reticulum (ER)-localized vesicle-associated membrane protein-associated proteins VAPA and VAPB defines ER-PM junctions in mammalian brain neurons. Here, we used proteomics to identify proteins associated with Kv2/VAP-containing ER-PM junctions. We found that the VAP-interacting membrane-associated phosphatidylinositol (PtdIns) transfer proteins PYK2 N-terminal domain-interacting receptor 2 (Nir2) and Nir3 specifically associate with Kv2.1 complexes. When coexpressed with Kv2.1 and VAPA in HEK293T cells, Nir2 colocalized with cell-surface-conducting and -nonconducting Kv2.1 isoforms. This was enhanced by muscarinic-mediated PtdIns(4,5)P2 hydrolysis, leading to dynamic recruitment of Nir2 to Kv2.1 clusters. In cultured rat hippocampal neurons, exogenously expressed Nir2 did not strongly colocalize with Kv2.1, unless exogenous VAPA was also expressed, supporting the notion that VAPA mediates the spatial association of Kv2.1 and Nir2. Immunolabeling signals of endogenous Kv2.1, Nir2, and VAP puncta were spatially correlated in cultured neurons. Fluorescence-recovery-after-photobleaching experiments revealed that Kv2.1, VAPA, and Nir2 have comparable turnover rates at ER-PM junctions, suggesting that they form complexes at these sites. Exogenous Kv2.1 expression in HEK293T cells resulted in significant differences in the kinetics of PtdIns(4,5)P2 recovery following repetitive muscarinic stimulation, with no apparent impact on resting PtdIns(4,5)P2 or PtdIns(4)P levels. Finally, the brains of Kv2.1-knockout mice had altered composition of PtdIns lipids, suggesting a crucial role for native Kv2.1-containing ER-PM junctions in regulating PtdIns lipid metabolism in brain neurons. These results suggest that ER-PM junctions formed by Kv2 channel-VAP pairing regulate PtdIns lipid homeostasis via VAP-associated PtdIns transfer proteins.
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Affiliation(s)
- Michael Kirmiz
- Department of Neurobiology, Physiology, and Behavior, University of California, Davis, California 95616
| | - Taryn E Gillies
- Department of Bioengineering, Stanford University, Stanford, California 94305
| | - Eamonn J Dickson
- Department of Physiology and Membrane Biology, University of California Davis School of Medicine, Davis, California 95616
| | - James S Trimmer
- Department of Neurobiology, Physiology, and Behavior, University of California, Davis, California 95616 .,Department of Physiology and Membrane Biology, University of California Davis School of Medicine, Davis, California 95616
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17
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Blunsom NJ, Gomez-Espinosa E, Ashlin TG, Cockcroft S. Sustained phospholipase C stimulation of H9c2 cardiomyoblasts by vasopressin induces an increase in CDP-diacylglycerol synthase 1 (CDS1) through protein kinase C and cFos. Biochim Biophys Acta Mol Cell Biol Lipids 2019; 1864:1072-1082. [PMID: 30862571 PMCID: PMC6495107 DOI: 10.1016/j.bbalip.2019.03.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 02/28/2019] [Accepted: 03/06/2019] [Indexed: 01/18/2023]
Abstract
Chronic stimulation (24 h) with vasopressin leads to hypertrophy in H9c2 cardiomyoblasts and this is accompanied by continuous activation of phospholipase C. Consequently, vasopressin stimulation leads to a depletion of phosphatidylinositol levels. The substrate for phospholipase C is phosphatidylinositol (4, 5) bisphosphate (PIP2) and resynthesis of phosphatidylinositol and its subsequent phosphorylation maintains the supply of PIP2. The resynthesis of PI requires the conversion of phosphatidic acid to CDP-diacylglycerol catalysed by CDP-diacylglycerol synthase (CDS) enzymes. To examine whether the resynthesis of PI is regulated by vasopressin stimulation, we focussed on the CDS enzymes. Three CDS enzymes are present in mammalian cells: CDS1 and CDS2 are integral membrane proteins localised at the endoplasmic reticulum and TAMM41 is a peripheral protein localised in the mitochondria. Vasopressin selectively stimulates an increase CDS1 mRNA that is dependent on protein kinase C, and can be inhibited by the AP-1 inhibitor, T-5224. Vasopressin also stimulates an increase in cFos protein which is inhibited by a protein kinase C inhibitor. We conclude that vasopressin stimulates CDS1 mRNA through phospholipase C, protein kinase C and cFos and provides a potential mechanism for maintenance of phosphatidylinositol levels during long-term phospholipase C signalling.
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Affiliation(s)
- Nicholas J Blunsom
- Dept. of Neuroscience, Physiology and Pharmacology, Division of Biosciences, University College London, London WC1E 6JJ, UK
| | - Evelyn Gomez-Espinosa
- Dept. of Neuroscience, Physiology and Pharmacology, Division of Biosciences, University College London, London WC1E 6JJ, UK
| | - Tim G Ashlin
- Dept. of Neuroscience, Physiology and Pharmacology, Division of Biosciences, University College London, London WC1E 6JJ, UK
| | - Shamshad Cockcroft
- Dept. of Neuroscience, Physiology and Pharmacology, Division of Biosciences, University College London, London WC1E 6JJ, UK.
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18
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Jing J, Liu G, Huang Y, Zhou Y. A molecular toolbox for interrogation of membrane contact sites. J Physiol 2019; 598:1725-1739. [PMID: 31119749 PMCID: PMC7098838 DOI: 10.1113/jp277761] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 04/17/2019] [Indexed: 01/04/2023] Open
Abstract
Membrane contact sites (MCSs) are specialized subcellular compartments formed by closely apposed membranes from two organelles. The intermembrane gap is separated by a distance ranging from 10 to 35 nm. MCSs are typically maintained through dynamic protein–protein and protein–lipid interactions. These intermembrane contact sites constitute important intracellular signalling hotspots to mediate a plethora of cellular processes, including calcium homeostasis, lipid metabolism, membrane biogenesis and organelle remodelling. In recent years, a series of genetically encoded probes and chemogenetic or optogenetic actuators have been invented to aid the visualization and interrogation of MCSs in both fixed and living cells. These molecular tools have greatly accelerated the pace of mechanistic dissection of membrane contact sites at the molecular level. In this review, we present an overview on the latest progress in this endeavour, and provide a general guide to the selection of methods and molecular tools for probing interorganellar membrane contact sites.
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Affiliation(s)
- Ji Jing
- Center for Translational Cancer Research, Institute of Biosciences and Technology, College of Medicine, Texas A&M University, Houston, TX, 77030, USA
| | - Gan Liu
- Cockrell School of Engineering, University of Texas, Austin, TX, 78712, USA
| | - Yun Huang
- Center for Epigenetics and Disease Prevention, Institute of Biosciences and Technology, College of Medicine, Texas A&M University, Houston, TX, 77030, USA
| | - Yubin Zhou
- Center for Translational Cancer Research, Institute of Biosciences and Technology, College of Medicine, Texas A&M University, Houston, TX, 77030, USA
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19
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Genevini P, Colombo MN, Venditti R, Marcuzzo S, Colombo SF, Bernasconi P, De Matteis MA, Borgese N, Navone F. VAPB depletion alters neuritogenesis and phosphoinositide balance in motoneuron-like cells: relevance to VAPB-linked amyotrophic lateral sclerosis. J Cell Sci 2019; 132:jcs.220061. [PMID: 30745341 DOI: 10.1242/jcs.220061] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 02/01/2019] [Indexed: 12/12/2022] Open
Abstract
VAPB and VAPA are ubiquitously expressed endoplasmic reticulum membrane proteins that play key roles in lipid exchange at membrane contact sites. A mutant, aggregation-prone, form of VAPB (P56S) is linked to a dominantly inherited form of amyotrophic lateral sclerosis; however, it has been unclear whether its pathogenicity is due to toxic gain of function, to negative dominance, or simply to insufficient levels of the wild-type protein produced from a single allele (haploinsufficiency). To investigate whether reduced levels of functional VAPB, independently from the presence of the mutant form, affect the physiology of mammalian motoneuron-like cells, we generated NSC34 clones, from which VAPB was partially or nearly completely depleted. VAPA levels, determined to be over fourfold higher than those of VAPB in untransfected cells, were unaffected. Nonetheless, cells with even partially depleted VAPB showed an increase in Golgi- and acidic vesicle-localized phosphatidylinositol-4-phosphate (PI4P) and reduced neurite extension when induced to differentiate. Conversely, the PI4 kinase inhibitors PIK93 and IN-10 increased neurite elongation. Thus, for long-term survival, motoneurons might require the full dose of functional VAPB, which may have unique function(s) that VAPA cannot perform.
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Affiliation(s)
- Paola Genevini
- Consiglio Nazionale delle Ricerche Neuroscience Institute and BIOMETRA Department, Università degli Studi di Milano, Milan 20129, Italy
| | - Maria Nicol Colombo
- Consiglio Nazionale delle Ricerche Neuroscience Institute and BIOMETRA Department, Università degli Studi di Milano, Milan 20129, Italy
| | | | - Stefania Marcuzzo
- Neurology IV - Neuroimmunology and Neuromuscular Diseases Unit, Fondazione Istituto Neurologico 'Carlo Besta', Milan 20133, Italy
| | - Sara Francesca Colombo
- Consiglio Nazionale delle Ricerche Neuroscience Institute and BIOMETRA Department, Università degli Studi di Milano, Milan 20129, Italy
| | - Pia Bernasconi
- Neurology IV - Neuroimmunology and Neuromuscular Diseases Unit, Fondazione Istituto Neurologico 'Carlo Besta', Milan 20133, Italy
| | - Maria Antonietta De Matteis
- Telethon Institute of Genetics and Medicine, Pozzuoli 80078, Italy.,Department of Molecular Medicine and Medical Biotechnology, University of Naples Federico II, Naples 80133, Italy
| | - Nica Borgese
- Consiglio Nazionale delle Ricerche Neuroscience Institute and BIOMETRA Department, Università degli Studi di Milano, Milan 20129, Italy
| | - Francesca Navone
- Consiglio Nazionale delle Ricerche Neuroscience Institute and BIOMETRA Department, Università degli Studi di Milano, Milan 20129, Italy
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20
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Pemberton JG, Balla T. Polyphosphoinositide-Binding Domains: Insights from Peripheral Membrane and Lipid-Transfer Proteins. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1111:77-137. [PMID: 30483964 DOI: 10.1007/5584_2018_288] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Within eukaryotic cells, biochemical reactions need to be organized on the surface of membrane compartments that use distinct lipid constituents to dynamically modulate the functions of integral proteins or influence the selective recruitment of peripheral membrane effectors. As a result of these complex interactions, a variety of human pathologies can be traced back to improper communication between proteins and membrane surfaces; either due to mutations that directly alter protein structure or as a result of changes in membrane lipid composition. Among the known structural lipids found in cellular membranes, phosphatidylinositol (PtdIns) is unique in that it also serves as the membrane-anchored precursor of low-abundance regulatory lipids, the polyphosphoinositides (PPIn), which have restricted distributions within specific subcellular compartments. The ability of PPIn lipids to function as signaling platforms relies on both non-specific electrostatic interactions and the selective stereospecific recognition of PPIn headgroups by specialized protein folds. In this chapter, we will attempt to summarize the structural diversity of modular PPIn-interacting domains that facilitate the reversible recruitment and conformational regulation of peripheral membrane proteins. Outside of protein folds capable of capturing PPIn headgroups at the membrane interface, recent studies detailing the selective binding and bilayer extraction of PPIn species by unique functional domains within specific families of lipid-transfer proteins will also be highlighted. Overall, this overview will help to outline the fundamental physiochemical mechanisms that facilitate localized interactions between PPIn lipids and the wide-variety of PPIn-binding proteins that are essential for the coordinate regulation of cellular metabolism and membrane dynamics.
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Affiliation(s)
- Joshua G Pemberton
- Section on Molecular Signal Transduction, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
| | - Tamas Balla
- Section on Molecular Signal Transduction, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA.
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21
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Grabon A, Bankaitis VA, McDermott MI. The interface between phosphatidylinositol transfer protein function and phosphoinositide signaling in higher eukaryotes. J Lipid Res 2018; 60:242-268. [PMID: 30504233 DOI: 10.1194/jlr.r089730] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 11/12/2018] [Indexed: 12/22/2022] Open
Abstract
Phosphoinositides are key regulators of a large number of diverse cellular processes that include membrane trafficking, plasma membrane receptor signaling, cell proliferation, and transcription. How a small number of chemically distinct phosphoinositide signals are functionally amplified to exert specific control over such a diverse set of biological outcomes remains incompletely understood. To this end, a novel mechanism is now taking shape, and it involves phosphatidylinositol (PtdIns) transfer proteins (PITPs). The concept that PITPs exert instructive regulation of PtdIns 4-OH kinase activities and thereby channel phosphoinositide production to specific biological outcomes, identifies PITPs as central factors in the diversification of phosphoinositide signaling. There are two evolutionarily distinct families of PITPs: the Sec14-like and the StAR-related lipid transfer domain (START)-like families. Of these two families, the START-like PITPs are the least understood. Herein, we review recent insights into the biochemical, cellular, and physiological function of both PITP families with greater emphasis on the START-like PITPs, and we discuss the underlying mechanisms through which these proteins regulate phosphoinositide signaling and how these actions translate to human health and disease.
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Affiliation(s)
- Aby Grabon
- E. L. Wehner-Welch Laboratory, Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX 77843-1114
| | - Vytas A Bankaitis
- E. L. Wehner-Welch Laboratory, Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX 77843-1114
| | - Mark I McDermott
- E. L. Wehner-Welch Laboratory, Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX 77843-1114
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22
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Abstract
Membrane biology seeks to understand how lipids and proteins within bilayers assemble into large structures such as organelles and the plasma membranes. Historically, lipids were thought to merely provide structural support for bilayer formation and membrane protein function. Research has now revealed that phospholipid metabolism regulates nearly all cellular processes. Sophisticated techniques helped identify >10,000 lipid species suggesting that lipids support many biological processes. Here, we highlight the synthesis of the most abundant glycerophospholipid classes and their distribution in organelles. We review vesicular and nonvesicular transport pathways shuttling lipids between organelles and discuss lipid regulators of membrane trafficking and second messengers in eukaryotic cells.
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Affiliation(s)
- Yanbo Yang
- From the Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, Ontario M5B 1W8.,the Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, and
| | - Minhyoung Lee
- From the Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, Ontario M5B 1W8.,the Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, and
| | - Gregory D Fairn
- From the Keenan Research Centre for Biomedical Science, St. Michael's Hospital, Toronto, Ontario M5B 1W8, .,the Department of Biochemistry, University of Toronto, Toronto, Ontario M5S 1A8, and.,the Department of Surgery, University of Toronto, Toronto, Ontario M5T 1P5, Canada
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