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Hartopp N, Markovinovic A, Miller CCJ, Gomez-Suaga P. Insight into endoplasmic reticulum-mitochondria contacts in human amyotrophic lateral sclerosis. Neural Regen Res 2024; 19:1407-1408. [PMID: 38051870 PMCID: PMC10883496 DOI: 10.4103/1673-5374.387988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Revised: 08/29/2023] [Accepted: 09/11/2023] [Indexed: 12/07/2023] Open
Affiliation(s)
- Naomi Hartopp
- Sheffield Institute for Translational Neuroscience, University of Sheffield, Sheffield, UK
| | - Andrea Markovinovic
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Christopher CJ Miller
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, London, UK
| | - Patricia Gomez-Suaga
- Universidad de Extremadura. Departamento de Bioquímica y Biología Molecular y Genética, Facultad de Enfermería y Terapia Ocupacional, Cáceres, Spain
- Centro de Investigación Biomédica en Red en Enfermedades Neurodegenerativas-Instituto de Salud Carlos III (CIBER-CIBERNED-ISCIII), Madrid, Spain
- Instituto Universitario de Investigación Biosanitaria de Extremadura (INUBE), Cáceres, Spain
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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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Cheng D, Lei ZG, Chu K, Lam OJH, Chiang CY, Zhang ZJ. N, N-Dimethyltryptamine, a natural hallucinogen, ameliorates Alzheimer's disease by restoring neuronal Sigma-1 receptor-mediated endoplasmic reticulum-mitochondria crosstalk. Alzheimers Res Ther 2024; 16:95. [PMID: 38693554 PMCID: PMC11061967 DOI: 10.1186/s13195-024-01462-3] [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: 02/14/2024] [Accepted: 04/17/2024] [Indexed: 05/03/2024]
Abstract
BACKGROUND Aberrant neuronal Sigma-1 receptor (Sig-1r)-mediated endoplasmic reticulum (ER)- mitochondria signaling plays a key role in the neuronal cytopathology of Alzheimer's disease (AD). The natural psychedelic N, N-dimethyltryptamine (DMT) is a Sig-1r agonist that may have the anti-AD potential through protecting neuronal ER-mitochondrial interplay. METHODS 3×TG-AD transgenic mice were administered with chronic DMT (2 mg/kg) for 3 weeks and then performed water maze test. The Aβ accumulation in the mice brain were determined. The Sig-1r level upon DMT treatment was tested. The effect of DMT on the ER-mitochondrial contacts site and multiple mitochondria-associated membrane (MAM)-associated proteins were examined. The effect of DMT on calcium transport between ER and mitochondria and the mitochondrial function were also evaluated. RESULTS chronic DMT (2 mg/kg) markedly alleviated cognitive impairment of 3×TG-AD mice. In parallel, it largely diminished Aβ accumulation in the hippocampus and prefrontal cortex. DMT restored the decreased Sig-1r levels of 3×TG-AD transgenic mice. The hallucinogen reinstated the expression of multiple MAM-associated proteins in the brain of 3×TG-AD mice. DMT also prevented physical contact and calcium dynamic between the two organelles in in vitro and in vivo pathological circumstances. DMT modulated oxidative phosphorylation (OXPHOS) and ATP synthase in the in vitro model of AD. CONCLUSION The anti-AD effects of DMT are associated with its protection of neuronal ER-mitochondria crosstalk via the activation of Sig-1r. DMT has the potential to serve as a novel preventive and therapeutic agent against AD.
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Affiliation(s)
- Dan Cheng
- Department of Chinese Medicine, The University of Hong Kong-Shenzhen Hospital (HKU-SZH), Shenzhen, China
- School of Chinese Medicine, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Zhuo-Gui Lei
- Department of Neuroscience, City University of Hong Kong, Hong Kong, China
| | - Kin Chu
- Department of Psychology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China
| | - Oi Jin Honey Lam
- School of Biomedical Sciences, Faculty of Science, The University of Hong Kong, Hong Kong, China
| | - Chun Yuan Chiang
- Digital Centre of State Key Laboratory of Quality Research in Chinese Medicine, Macau, China
| | - Zhang-Jin Zhang
- Department of Chinese Medicine, The University of Hong Kong-Shenzhen Hospital (HKU-SZH), Shenzhen, China.
- School of Chinese Medicine, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China.
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Markovinovic A, Martín-Guerrero SM, Mórotz GM, Salam S, Gomez-Suaga P, Paillusson S, Greig J, Lee Y, Mitchell JC, Noble W, Miller CCJ. Stimulating VAPB-PTPIP51 ER-mitochondria tethering corrects FTD/ALS mutant TDP43 linked Ca 2+ and synaptic defects. Acta Neuropathol Commun 2024; 12:32. [PMID: 38395965 PMCID: PMC10885568 DOI: 10.1186/s40478-024-01742-x] [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: 09/20/2023] [Accepted: 02/05/2024] [Indexed: 02/25/2024] Open
Abstract
Frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) are clinically linked major neurodegenerative diseases. Notably, TAR DNA-binding protein-43 (TDP43) accumulations are hallmark pathologies of FTD/ALS and mutations in the gene encoding TDP43 cause familial FTD/ALS. There are no cures for FTD/ALS. FTD/ALS display damage to a broad range of physiological functions, many of which are regulated by signaling between the endoplasmic reticulum (ER) and mitochondria. This signaling is mediated by the VAPB-PTPIP51 tethering proteins that serve to recruit regions of ER to the mitochondrial surface so as to facilitate inter-organelle communications. Several studies have now shown that disrupted ER-mitochondria signaling including breaking of the VAPB-PTPIP51 tethers are features of FTD/ALS and that for TDP43 and other familial genetic FTD/ALS insults, this involves activation of glycogen kinase-3β (GSK3β). Such findings have prompted suggestions that correcting damage to ER-mitochondria signaling and the VAPB-PTPIP51 interaction may be broadly therapeutic. Here we provide evidence to support this notion. We show that overexpression of VAPB or PTPIP51 to enhance ER-mitochondria signaling corrects mutant TDP43 induced damage to inositol 1,4,5-trisphosphate (IP3) receptor delivery of Ca2+ to mitochondria which is a primary function of the VAPB-PTPIP51 tethers, and to synaptic function. Moreover, we show that ursodeoxycholic acid (UDCA), an FDA approved drug linked to FTD/ALS and other neurodegenerative diseases therapy and whose precise therapeutic target is unclear, corrects TDP43 linked damage to the VAPB-PTPIP51 interaction. We also show that this effect involves inhibition of TDP43 mediated activation of GSK3β. Thus, correcting damage to the VAPB-PTPIP51 tethers may have therapeutic value for FTD/ALS and other age-related neurodegenerative diseases.
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Affiliation(s)
- Andrea Markovinovic
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK.
| | - Sandra M Martín-Guerrero
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK
| | - Gábor M Mórotz
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK
| | - Shaakir Salam
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK
| | - Patricia Gomez-Suaga
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK
| | - Sebastien Paillusson
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK
| | - Jenny Greig
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK
| | - Younbok Lee
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK
| | - Jacqueline C Mitchell
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK
| | - Wendy Noble
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK
| | - Christopher C J Miller
- Department of Basic and Clinical Neuroscience, Institute of Psychiatry, Psychology and Neuroscience, King's College London, SE5 9RX, London, UK.
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Momin ID, Rigler J, Chitrala KN. Analysis of Potential Biomarkers in Frontal Temporal Dementia: A Bioinformatics Approach. Int J Mol Sci 2023; 24:14910. [PMID: 37834358 PMCID: PMC10573524 DOI: 10.3390/ijms241914910] [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: 08/06/2023] [Revised: 09/29/2023] [Accepted: 10/03/2023] [Indexed: 10/15/2023] Open
Abstract
Frontal temporal dementia (FTD) is a neurological disorder known to have fewer therapeutic options. So far, only a few biomarkers are available for FTD that can be used as potential comorbidity targets. For example, genes such as VCP, which has a role in breast cancer, and WFS1, which has a role in COVID-19, are known to show a role in FTD as well. To this end, in the present study, we aim to identify potential biomarkers or susceptible genes for FTD that show comorbidities with diseases such as COVID-19 and breast cancer. A dataset from Gene Expression Omnibus containing FTD expression profiles from African American and white ethnicity backgrounds was included in our study. In FTD samples of the GSE193391 dataset, we identified 305 DEGs, with 168 genes being up-regulated and 137 genes being down-regulated. We conducted a comorbidity analysis for COVID-19 and breast cancer, followed by an analysis of potential drug interactions, pathogenicity, analysis of genetic variants, and functional enrichment analysis. Our results showed that the genes AKT3, GFAP, ADCYAP1R1, VDAC1, and C4A have significant transcriptomic alterations in FTD along with the comorbidity status with COVID-19 and breast cancer. Functional pathway analysis revealed that these comorbid genes were significantly enriched in the pathways such as glioma, JAK/STAT signaling, systematic lupus erythematosus, neurodegeneration-multiple diseases, and neuroactive ligand-receptor interaction. Overall, from these results, we concluded that these genes could be recommended as potential therapeutic targets for the treatment of comorbidities (breast cancer and COVID-19) in patients with FTD.
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Affiliation(s)
| | | | - Kumaraswamy Naidu Chitrala
- Department of Engineering Technology, University of Houston, Sugar Land, TX 77479, USA; (I.D.M.); (J.R.)
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Rühmkorf A, Harbauer AB. Role of Mitochondria-ER Contact Sites in Mitophagy. Biomolecules 2023; 13:1198. [PMID: 37627263 PMCID: PMC10452924 DOI: 10.3390/biom13081198] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 07/28/2023] [Accepted: 07/29/2023] [Indexed: 08/27/2023] Open
Abstract
Mitochondria are often referred to as the "powerhouse" of the cell. However, this organelle has many more functions than simply satisfying the cells' metabolic needs. Mitochondria are involved in calcium homeostasis and lipid metabolism, and they also regulate apoptotic processes. Many of these functions require contact with the ER, which is mediated by several tether proteins located on the respective organellar surfaces, enabling the formation of mitochondria-ER contact sites (MERCS). Upon damage, mitochondria produce reactive oxygen species (ROS) that can harm the surrounding cell. To circumvent toxicity and to maintain a functional pool of healthy organelles, damaged and excess mitochondria can be targeted for degradation via mitophagy, a form of selective autophagy. Defects in mitochondria-ER tethers and the accumulation of damaged mitochondria are found in several neurodegenerative diseases, including Parkinson's disease and amyotrophic lateral sclerosis, which argues that the interplay between the two organelles is vital for neuronal health. This review provides an overview of the different mechanisms of mitochondrial quality control that are implicated with the different mitochondria-ER tether proteins, and also provides a novel perspective on how MERCS are involved in mediating mitophagy upon mitochondrial damage.
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Affiliation(s)
- Alina Rühmkorf
- TUM Medical Graduate Center, Technical University of Munich, 81675 Munich, Germany
- Max Planck Institute for Biological Intelligence, 82152 Planegg-Martinsried, Germany
| | - Angelika Bettina Harbauer
- Max Planck Institute for Biological Intelligence, 82152 Planegg-Martinsried, Germany
- Institute of Neuronal Cell Biology, Technical University of Munich, 80802 Munich, Germany
- Munich Cluster for Systems Neurology, 81377 Munich, Germany
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de Ridder I, Kerkhofs M, Lemos FO, Loncke J, Bultynck G, Parys JB. The ER-mitochondria interface, where Ca 2+ and cell death meet. Cell Calcium 2023; 112:102743. [PMID: 37126911 DOI: 10.1016/j.ceca.2023.102743] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Revised: 04/20/2023] [Accepted: 04/24/2023] [Indexed: 05/03/2023]
Abstract
Endoplasmic reticulum (ER)-mitochondria contact sites are crucial to allow Ca2+ flux between them and a plethora of proteins participate in tethering both organelles together. Inositol 1,4,5-trisphosphate receptors (IP3Rs) play a pivotal role at such contact sites, participating in both ER-mitochondria tethering and as Ca2+-transport system that delivers Ca2+ from the ER towards mitochondria. At the ER-mitochondria contact sites, the IP3Rs function as a multi-protein complex linked to the voltage-dependent anion channel 1 (VDAC1) in the outer mitochondrial membrane, via the chaperone glucose-regulated protein 75 (GRP75). This IP3R-GRP75-VDAC1 complex supports the efficient transfer of Ca2+ from the ER into the mitochondrial intermembrane space, from which the Ca2+ ions can reach the mitochondrial matrix through the mitochondrial calcium uniporter. Under physiological conditions, basal Ca2+ oscillations deliver Ca2+ to the mitochondrial matrix, thereby stimulating mitochondrial oxidative metabolism. However, when mitochondrial Ca2+ overload occurs, the increase in [Ca2+] will induce the opening of the mitochondrial permeability transition pore, thereby provoking cell death. The IP3R-GRP75-VDAC1 complex forms a hub for several other proteins that stabilize the complex and/or regulate the complex's ability to channel Ca2+ into the mitochondria. These proteins and their mechanisms of action are discussed in the present review with special attention for their role in pathological conditions and potential implication for therapeutic strategies.
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Affiliation(s)
- Ian de Ridder
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium
| | - Martijn Kerkhofs
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium
| | - Fernanda O Lemos
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium
| | - Jens Loncke
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium
| | - Geert Bultynck
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium.
| | - Jan B Parys
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium.
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Arjona SP, Allen CNS, Santerre M, Gross S, Soboloff J, Booze R, Sawaya BE. Disruption of Mitochondrial-associated ER membranes by HIV-1 tat protein contributes to premature brain aging. CNS Neurosci Ther 2022; 29:365-377. [PMID: 36419337 PMCID: PMC9804058 DOI: 10.1111/cns.14011] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 10/04/2022] [Accepted: 10/19/2022] [Indexed: 11/27/2022] Open
Abstract
INTRODUCTION Mitochondrial-associated ER membranes (MAMs) control many cellular functions, including calcium and lipid exchange, intracellular trafficking, and mitochondrial biogenesis. The disruption of these functions contributes to neurocognitive disorders, such as spatial memory impairment and premature brain aging. Using neuronal cells, we demonstrated that HIV-1 Tat protein deregulates the mitochondria. METHODS& RESULTS To determine the mechanisms, we used a neuronal cell line and showed that Tat-induced changes in expression and interactions of both MAM-associated proteins and MAM tethering proteins. The addition of HIV-1 Tat protein alters expression levels of PTPIP51 and VAPB proteins in the MAM fraction but not the whole cell. Phosphorylation of PTPIP51 protein regulates its subcellular localization and function. We demonstrated that the Tat protein promotes PTPIP51 phosphorylation on tyrosine residues and prevents its binding to VAPB. Treatment of the cells with a kinase inhibitor restores the PTPIP51-VAPB interaction and overcomes the effect of Tat. CONCLUSION These results suggest that Tat disrupts the MAM, through the induction of PTPIP51 phosphorylation, leading to ROS accumulation, mitochondrial stress, and altered movement. Hence, we concluded that interfering in the MAM-associated cellular pathways contributes to spatial memory impairment and premature brain aging often observed in HIV-1-infected patients.
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Affiliation(s)
- Sterling P. Arjona
- Molecular Studies of Neurodegenerative Diseases Lab, Fels Cancer Institute for Personalized Medicine, Lewis Katz School of MedicineTemple UniversityPhiladelphiaPennsylvaniaUSA
| | - Charles N. S. Allen
- Molecular Studies of Neurodegenerative Diseases Lab, Fels Cancer Institute for Personalized Medicine, Lewis Katz School of MedicineTemple UniversityPhiladelphiaPennsylvaniaUSA
| | - Maryline Santerre
- Molecular Studies of Neurodegenerative Diseases Lab, Fels Cancer Institute for Personalized Medicine, Lewis Katz School of MedicineTemple UniversityPhiladelphiaPennsylvaniaUSA
| | - Scott Gross
- Fels Cancer Institute for Personalized Medicine, Lewis Katz School of MedicineTemple UniversityPhiladelphiaPennsylvaniaUSA
| | - Jonathan Soboloff
- Fels Cancer Institute for Personalized Medicine, Lewis Katz School of MedicineTemple UniversityPhiladelphiaPennsylvaniaUSA
| | - Rosemarie Booze
- Program of Behavioral Neuroscience, Department of PsychologyUniversity of South CarolinaColumbiaSouth CarolinaUSA
| | - Bassel E. Sawaya
- Molecular Studies of Neurodegenerative Diseases Lab, Fels Cancer Institute for Personalized Medicine, Lewis Katz School of MedicineTemple UniversityPhiladelphiaPennsylvaniaUSA,Department of Cancer and Cellular BiologyLewis Katz School of Medicine, Temple UniversityPhiladelphiaPennsylvaniaUSA,Department of Neural SciencesLewis Katz School of Medicine, Temple UniversityPhiladelphiaPennsylvaniaUSA
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Kors S, Kurian SM, Costello JL, Schrader M. Controlling contacts-Molecular mechanisms to regulate organelle membrane tethering. Bioessays 2022; 44:e2200151. [PMID: 36180400 DOI: 10.1002/bies.202200151] [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: 08/03/2022] [Revised: 09/07/2022] [Accepted: 09/12/2022] [Indexed: 11/06/2022]
Abstract
In recent years, membrane contact sites (MCS), which mediate interactions between virtually all subcellular organelles, have been extensively characterized and shown to be essential for intracellular communication. In this review essay, we focus on an emerging topic: the regulation of MCS. Focusing on the tether proteins themselves, we discuss some of the known mechanisms which can control organelle tethering events and identify apparent common regulatory hubs, such as the VAP interface at the endoplasmic reticulum (ER). We also highlight several currently hypothetical concepts, including the idea of tether oligomerization and redox regulation playing a role in MCS formation. We identify gaps in our current understanding, such as the identity of the majority of kinases/phosphatases involved in tether modification and conclude that a holistic approach-incorporating the formation of multiple MCS, regulated by interconnected regulatory modulators-may be required to fully appreciate the true complexity of these fascinating intracellular communication systems.
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Affiliation(s)
- Suzan Kors
- College of Life and Environmental Sciences, Biosciences, University of Exeter, Exeter, UK
| | - Smija M Kurian
- College of Life and Environmental Sciences, Biosciences, University of Exeter, Exeter, UK
| | - Joseph L Costello
- College of Life and Environmental Sciences, Biosciences, University of Exeter, Exeter, UK
| | - Michael Schrader
- College of Life and Environmental Sciences, Biosciences, University of Exeter, Exeter, UK
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