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Morleo M, Venditti R, Theodorou E, Briere LC, Rosello M, Tirozzi A, Tammaro R, Al-Badri N, High FA, Shi J, Putti E, Ferrante L, Cetrangolo V, Torella A, Walker MA, Tenconi R, Iascone M, Mei D, Guerrini R, van der Smagt J, Kroes HY, van Gassen KLI, Bilal M, Umair M, Pingault V, Attie-Bitach T, Amiel J, Ejaz R, Rodan L, Zollino M, Agrawal PB, Del Bene F, Nigro V, Sweetser DA, Franco B. De novo missense variants in phosphatidylinositol kinase PIP5KIγ underlie a neurodevelopmental syndrome associated with altered phosphoinositide signaling. Am J Hum Genet 2023; 110:1377-1393. [PMID: 37451268 PMCID: PMC10432144 DOI: 10.1016/j.ajhg.2023.06.012] [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: 01/24/2023] [Revised: 06/22/2023] [Accepted: 06/22/2023] [Indexed: 07/18/2023] Open
Abstract
Phosphoinositides (PIs) are membrane phospholipids produced through the local activity of PI kinases and phosphatases that selectively add or remove phosphate groups from the inositol head group. PIs control membrane composition and play key roles in many cellular processes including actin dynamics, endosomal trafficking, autophagy, and nuclear functions. Mutations in phosphatidylinositol 4,5 bisphosphate [PI(4,5)P2] phosphatases cause a broad spectrum of neurodevelopmental disorders such as Lowe and Joubert syndromes and congenital muscular dystrophy with cataracts and intellectual disability, which are thus associated with increased levels of PI(4,5)P2. Here, we describe a neurodevelopmental disorder associated with an increase in the production of PI(4,5)P2 and with PI-signaling dysfunction. We identified three de novo heterozygous missense variants in PIP5K1C, which encodes an isoform of the phosphatidylinositol 4-phosphate 5-kinase (PIP5KIγ), in nine unrelated children exhibiting intellectual disability, developmental delay, acquired microcephaly, seizures, visual abnormalities, and dysmorphic features. We provide evidence that the PIP5K1C variants result in an increase of the endosomal PI(4,5)P2 pool, giving rise to ectopic recruitment of filamentous actin at early endosomes (EEs) that in turn causes dysfunction in EE trafficking. In addition, we generated an in vivo zebrafish model that recapitulates the disorder we describe with developmental defects affecting the forebrain, including the eyes, as well as craniofacial abnormalities, further demonstrating the pathogenic effect of the PIP5K1C variants.
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Affiliation(s)
- Manuela Morleo
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy; Department of Precision Medicine, University of Campania "Luigi Vanvitelli," Naples, Italy.
| | - Rossella Venditti
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy; Department of Molecular Medicine and Medical Biotechnology, University of Naples "Federico II," Medical School, Naples, Italy
| | - Evangelos Theodorou
- Center for Genomic Medicine, Divisions of Pediatric Hematology/Oncology and Medical Genetics and Metabolism, Department of Pediatrics, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Lauren C Briere
- Center for Genomic Medicine, Divisions of Pediatric Hematology/Oncology and Medical Genetics and Metabolism, Department of Pediatrics, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Marion Rosello
- Sorbonne Université, INSERM U968, CNRS UMR 7210, Institut de la Vision, Paris, France
| | - Alfonsina Tirozzi
- Department of Precision Medicine, University of Campania "Luigi Vanvitelli," Naples, Italy; Department of Epidemiology and Prevention, IRCCS NEUROMED, Pozzilli, Italy
| | - Roberta Tammaro
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy
| | - Nour Al-Badri
- Sorbonne Université, INSERM U968, CNRS UMR 7210, Institut de la Vision, Paris, France
| | - Frances A High
- Division of Medical Genetics & Metabolism, Massachusetts General Hospital for Children, Boston, MA 02114, USA
| | - Jiahai Shi
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Elena Putti
- Sorbonne Université, INSERM U968, CNRS UMR 7210, Institut de la Vision, Paris, France
| | - Luigi Ferrante
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy
| | - Viviana Cetrangolo
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy
| | - Annalaura Torella
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy; Department of Precision Medicine, University of Campania "Luigi Vanvitelli," Naples, Italy
| | - Melissa A Walker
- Department of Neurology, Division of Neurogenetics, Child Neurology, Massachusetts General Hospital, Boston, MA, USA
| | - Romano Tenconi
- Clinical Genetics Unit, Department of Women and Children's Health, University of Padova, Padova, Italy
| | - Maria Iascone
- Medical Genetics, ASST Papa Giovanni XXIII, 24127 Bergamo, Italy
| | - Davide Mei
- Meyer Children's Hospital IRCCS, Neuroscience Department, Florence, Italy
| | - Renzo Guerrini
- Meyer Children's Hospital IRCCS, Neuroscience Department, Florence, Italy
| | - Jasper van der Smagt
- Department of Genetics, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Hester Y Kroes
- Department of Genetics, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Koen L I van Gassen
- Department of Genetics, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Muhammad Bilal
- Department of Biochemistry, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Muhammad Umair
- Medical Genomics Research Department, King Abdullah International Medical Research Center & King Saud Bin Abdulaziz University for Health Sciences, Ministry of National Guard Health Affairs, Riyadh, Saudi Arabia
| | - Veronica Pingault
- Service de Médecine Génomique des Maladies Rares, et Institut Imagine, Hôpital Necker-Enfants Malades, Paris, France
| | - Tania Attie-Bitach
- Service de Médecine Génomique des Maladies Rares, et Institut Imagine, Hôpital Necker-Enfants Malades, Paris, France
| | - Jeannine Amiel
- Service de Médecine Génomique des Maladies Rares, et Institut Imagine, Hôpital Necker-Enfants Malades, Paris, France
| | - Resham Ejaz
- Division of Genetics, Department of Pediatrics, McMaster Children's Hospital, Hamilton, ON, Canada
| | - Lance Rodan
- Department of Neurology, Boston Children's Hospital, Boston, MA, USA; Division of Genetics and Genomics, Department of Pediatrics, Boston Children's Hospital, Boston, MA, USA
| | - Marcella Zollino
- Institute of Medical Genetics, A. Gemelli School of Medicine, Catholic University of the Sacred Heart, Rome, Italy
| | - Pankaj B Agrawal
- Divisions of Newborn Medicine, Boston Children's Hospital, Boston, MA, USA; Genetics and Genomics, The Manton Center for Orphan Disease Research, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA
| | - Filippo Del Bene
- Sorbonne Université, INSERM U968, CNRS UMR 7210, Institut de la Vision, Paris, France
| | - Vincenzo Nigro
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy; Department of Precision Medicine, University of Campania "Luigi Vanvitelli," Naples, Italy
| | - David A Sweetser
- Center for Genomic Medicine, Divisions of Pediatric Hematology/Oncology and Medical Genetics and Metabolism, Department of Pediatrics, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA.
| | - Brunella Franco
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli, Naples, Italy; Scuola Superiore Meridionale (SSM, School of Advanced Studies), Genomics and Experimental Medicine Program, Naples, Italy; Medical Genetics, Department of Translational Medicine, University of Naples "Federico II," Via Sergio Pansini, 80131 Naples, Italy
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2
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Bura A, Čabrijan S, Đurić I, Bruketa T, Jurak Begonja A. A Plethora of Functions Condensed into Tiny Phospholipids: The Story of PI4P and PI(4,5)P 2. Cells 2023; 12:1411. [PMID: 37408244 DOI: 10.3390/cells12101411] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 05/08/2023] [Accepted: 05/09/2023] [Indexed: 07/07/2023] Open
Abstract
Phosphoinositides (PIs) are small, phosphorylated lipids that serve many functions in the cell. They regulate endo- and exocytosis, vesicular trafficking, actin reorganization, and cell mobility, and they act as signaling molecules. The most abundant PIs in the cell are phosphatidylinositol-4-monophosphate (PI4P) and phosphatidylinositol-4,5-bisphosphate [PI(4,5)P2]. PI4P is mostly localized at the Golgi apparatus where it regulates the anterograde trafficking from the Golgi apparatus to the plasma membrane (PM), but it also localizes at the PM. On the other hand, the main localization site of PI(4,5)P2 is the PM where it regulates the formation of endocytic vesicles. The levels of PIs are regulated by many kinases and phosphatases. Four main kinases phosphorylate the precursor molecule phosphatidylinositol into PI4P, divided into two classes (PI4KIIα, PI4KIIβ, PI4KIIIα, and PI4KIIIβ), and three main kinases phosphorylate PI4P to form PI(4,5)P2 (PI4P5KIα, PI4P5KIβ, and PI4P5KIγ). In this review, we discuss the localization and function of the kinases that produce PI4P and PI(4,5)P2, as well as the localization and function of their product molecules with an overview of tools for the detection of these PIs.
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Affiliation(s)
- Ana Bura
- Laboratory of Hematopoiesis, Department of Biotechnology, University of Rijeka, R. Matejcic 2, 51000 Rijeka, Croatia
| | - Sara Čabrijan
- Laboratory of Hematopoiesis, Department of Biotechnology, University of Rijeka, R. Matejcic 2, 51000 Rijeka, Croatia
| | - Iris Đurić
- Laboratory of Hematopoiesis, Department of Biotechnology, University of Rijeka, R. Matejcic 2, 51000 Rijeka, Croatia
| | - Tea Bruketa
- Laboratory of Hematopoiesis, Department of Biotechnology, University of Rijeka, R. Matejcic 2, 51000 Rijeka, Croatia
| | - Antonija Jurak Begonja
- Laboratory of Hematopoiesis, Department of Biotechnology, University of Rijeka, R. Matejcic 2, 51000 Rijeka, Croatia
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Burroughs A, Aravind L. New biochemistry in the Rhodanese-phosphatase superfamily: emerging roles in diverse metabolic processes, nucleic acid modifications, and biological conflicts. NAR Genom Bioinform 2023; 5:lqad029. [PMID: 36968430 PMCID: PMC10034599 DOI: 10.1093/nargab/lqad029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 02/10/2023] [Accepted: 03/09/2023] [Indexed: 03/25/2023] Open
Abstract
The protein-tyrosine/dual-specificity phosphatases and rhodanese domains constitute a sprawling superfamily of Rossmannoid domains that use a conserved active site with a cysteine to catalyze a range of phosphate-transfer, thiotransfer, selenotransfer and redox activities. While these enzymes have been extensively studied in the context of protein/lipid head group dephosphorylation and various thiotransfer reactions, their overall diversity and catalytic potential remain poorly understood. Using comparative genomics and sequence/structure analysis, we comprehensively investigate and develop a natural classification for this superfamily. As a result, we identified several novel clades, both those which retain the catalytic cysteine and those where a distinct active site has emerged in the same location (e.g. diphthine synthase-like methylases and RNA 2' OH ribosyl phosphate transferases). We also present evidence that the superfamily has a wider range of catalytic capabilities than previously known, including a set of parallel activities operating on various sugar/sugar alcohol groups in the context of NAD+-derivatives and RNA termini, and potential phosphate transfer activities involving sugars and nucleotides. We show that such activities are particularly expanded in the RapZ-C-DUF488-DUF4326 clade, defined here for the first time. Some enzymes from this clade are predicted to catalyze novel DNA-end processing activities as part of nucleic-acid-modifying systems that are likely to function in biological conflicts between viruses and their hosts.
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Affiliation(s)
- A Maxwell Burroughs
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
| | - L Aravind
- National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, MD 20894, USA
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4
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Raut P, Obeng B, Waters H, Zimmerberg J, Gosse JA, Hess ST. Phosphatidylinositol 4,5-Bisphosphate Mediates the Co-Distribution of Influenza A Hemagglutinin and Matrix Protein M1 at the Plasma Membrane. Viruses 2022; 14:v14112509. [PMID: 36423118 PMCID: PMC9698905 DOI: 10.3390/v14112509] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 11/04/2022] [Accepted: 11/08/2022] [Indexed: 11/16/2022] Open
Abstract
The fully assembled influenza A virus (IAV) has on its surface the highest density of a single membrane protein found in nature-the glycoprotein hemagglutinin (HA) that mediates viral binding, entry, and assembly. HA clusters at the plasma membrane of infected cells, and the HA density (number of molecules per unit area) of these clusters correlates with the infectivity of the virus. Dense HA clusters are considered to mark the assembly site and ultimately lead to the budding of infectious IAV. The mechanism of spontaneous HA clustering, which occurs with or without other viral components, has not been elucidated. Using super-resolution fluorescence photoactivation localization microscopy (FPALM), we have previously shown that these HA clusters are interdependent on phosphatidylinositol 4,5-biphosphate (PIP2). Here, we show that the IAV matrix protein M1 co-clusters with PIP2, visualized using the pleckstrin homology domain. We find that cetylpyridinium chloride (CPC), which is a positively charged quaternary ammonium compound known for its antibacterial and antiviral properties at millimolar concentrations, disrupts M1 clustering and M1-PIP2 co-clustering at micromolar concentrations well below the critical micelle concentration (CMC). CPC also disrupts the co-clustering of M1 with HA at the plasma membrane, suggesting the role of host cell PIP2 clusters as scaffolds for gathering and concentrating M1 and HA to achieve their unusually high cluster densities in the IAV envelope.
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Affiliation(s)
- Prakash Raut
- Department of Physics and Astronomy, University of Maine, Orono, ME 04469-5709, USA
| | - Bright Obeng
- Department of Molecular and Biomedical Sciences, University of Maine, Orono, ME 04469-5735, USA
| | - Hang Waters
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-1855, USA
| | - Joshua Zimmerberg
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892-1855, USA
| | - Julie A. Gosse
- Department of Molecular and Biomedical Sciences, University of Maine, Orono, ME 04469-5735, USA
| | - Samuel T. Hess
- Department of Physics and Astronomy, University of Maine, Orono, ME 04469-5709, USA
- Correspondence:
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5
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An Arabidopsis mutant deficient in phosphatidylinositol-4-phosphate kinases ß1 and ß2 displays altered auxin-related responses in roots. Sci Rep 2022; 12:6947. [PMID: 35484296 PMCID: PMC9051118 DOI: 10.1038/s41598-022-10458-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 04/04/2022] [Indexed: 11/11/2022] Open
Abstract
Phosphatidylinositol 4-kinases (PI4Ks) are the first enzymes that commit phosphatidylinositol into the phosphoinositide pathway. Here, we show that Arabidopsis thaliana seedlings deficient in PI4Kβ1 and β2 have several developmental defects including shorter roots and unfinished cytokinesis. The pi4kβ1β2 double mutant was insensitive to exogenous auxin concerning inhibition of root length and cell elongation; it also responded more slowly to gravistimulation. The pi4kß1ß2 root transcriptome displayed some similarities to a wild type plant response to auxin. Yet, not all the genes displayed such a constitutive auxin-like response. Besides, most assessed genes did not respond to exogenous auxin. This is consistent with data with the transcriptional reporter DR5-GUS. The content of bioactive auxin in the pi4kß1ß2 roots was similar to that in wild-type ones. Yet, an enhanced auxin-conjugating activity was detected and the auxin level reporter DII-VENUS did not respond to exogenous auxin in pi4kß1ß2 mutant. The mutant exhibited altered subcellular trafficking behavior including the trapping of PIN-FORMED 2 protein in rapidly moving vesicles. Bigger and less fragmented vacuoles were observed in pi4kß1ß2 roots when compared to the wild type. Furthermore, the actin filament web of the pi4kß1ß2 double mutant was less dense than in wild-type seedling roots, and less prone to rebuilding after treatment with latrunculin B. A mechanistic model is proposed in which an altered PI4K activity leads to actin filament disorganization, changes in vesicle trafficking, and altered auxin homeostasis and response resulting in a pleiotropic root phenotypes.
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Raut P, Weller SR, Obeng B, Soos BL, West BE, Potts CM, Sangroula S, Kinney MS, Burnell JE, King BL, Gosse JA, Hess ST. Cetylpyridinium chloride (CPC) reduces zebrafish mortality from influenza infection: Super-resolution microscopy reveals CPC interference with multiple protein interactions with phosphatidylinositol 4,5-bisphosphate in immune function. Toxicol Appl Pharmacol 2022; 440:115913. [PMID: 35149080 PMCID: PMC8824711 DOI: 10.1016/j.taap.2022.115913] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 01/04/2022] [Accepted: 02/04/2022] [Indexed: 01/12/2023]
Abstract
The COVID-19 pandemic raises significance for a potential influenza therapeutic compound, cetylpyridinium chloride (CPC), which has been extensively used in personal care products as a positively-charged quaternary ammonium antibacterial agent. CPC is currently in clinical trials to assess its effects on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) morbidity. Two published studies have provided mouse and human data indicating that CPC may alleviate influenza infection, and here we show that CPC (0.1 μM, 1 h) reduces zebrafish mortality and viral load following influenza infection. However, CPC mechanisms of action upon viral-host cell interaction are currently unknown. We have utilized super-resolution fluorescence photoactivation localization microscopy to probe the mode of CPC action. Reduction in density of influenza viral protein hemagglutinin (HA) clusters is known to reduce influenza infectivity: here, we show that CPC (at non-cytotoxic doses, 5-10 μM) reduces HA density and number of HA molecules per cluster within the plasma membrane of NIH-3T3 mouse fibroblasts. HA is known to colocalize with the negatively-charged mammalian lipid phosphatidylinositol 4,5-bisphosphate (PIP2); here, we show that nanoscale co-localization of HA with the PIP2-binding Pleckstrin homology (PH) reporter in the plasma membrane is diminished by CPC. CPC also dramatically displaces the PIP2-binding protein myristoylated alanine-rich C-kinase substrate (MARCKS) from the plasma membrane of rat RBL-2H3 mast cells; this disruption of PIP2 is correlated with inhibition of mast cell degranulation. Together, these findings offer a PIP2-focused mechanism underlying CPC disruption of influenza and suggest potential pharmacological use of this drug as an influenza therapeutic to reduce global deaths from viral disease.
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Affiliation(s)
- Prakash Raut
- Department of Physics and Astronomy, University of Maine, Orono, ME, USA
| | - Sasha R Weller
- Department of Molecular and Biomedical Sciences, University of Maine, Orono, ME, USA
| | - Bright Obeng
- Department of Molecular and Biomedical Sciences, University of Maine, Orono, ME, USA
| | - Brandy L Soos
- Department of Molecular and Biomedical Sciences, University of Maine, Orono, ME, USA
| | - Bailey E West
- Department of Molecular and Biomedical Sciences, University of Maine, Orono, ME, USA
| | - Christian M Potts
- Department of Molecular and Biomedical Sciences, University of Maine, Orono, ME, USA
| | - Suraj Sangroula
- Department of Molecular and Biomedical Sciences, University of Maine, Orono, ME, USA
| | - Marissa S Kinney
- Department of Molecular and Biomedical Sciences, University of Maine, Orono, ME, USA
| | - John E Burnell
- Department of Molecular and Biomedical Sciences, University of Maine, Orono, ME, USA
| | - Benjamin L King
- Department of Molecular and Biomedical Sciences, University of Maine, Orono, ME, USA
| | - Julie A Gosse
- Department of Molecular and Biomedical Sciences, University of Maine, Orono, ME, USA.
| | - Samuel T Hess
- Department of Physics and Astronomy, University of Maine, Orono, ME, USA.
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Lai A, Cox CD, Chandra Sekar N, Thurgood P, Jaworowski A, Peter K, Baratchi S. Mechanosensing by Piezo1 and its implications for physiology and various pathologies. Biol Rev Camb Philos Soc 2021; 97:604-614. [PMID: 34781417 DOI: 10.1111/brv.12814] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 10/21/2021] [Accepted: 11/04/2021] [Indexed: 11/27/2022]
Abstract
Piezo1 is a mechanosensitive ion channel with essential roles in cardiovascular, lung, urinary, and immune functions. Piezo1 is widely distributed in different tissues in the human body and its specific roles have been identified following a decade of research; however, not all are well understood. Many structural and functional characteristics of Piezo1 have been discovered and are known to differ greatly from the characteristics of other mechanosensitive ion channels. Understanding the mechanisms by which this ion channel functions may be useful in determining its physiological roles in various organ systems. This review provides insight into the signalling pathways activated by mechanical stimulation of Piezo1 in various organ systems and cell types. We discuss downstream targets of Piezo1 and the overall effects resulting from Piezo1 activation, which may provide insights into potential treatment targets for diseases involving this ion channel.
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Affiliation(s)
- Austin Lai
- School of Health and Biomedical Sciences, RMIT University, 289 McKimmies Rd, Bundoora, Victoria, 3083, Australia
| | - Charles D Cox
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, 405 Liverpool St, Sydney, New South Wales, 2010, Australia
| | - Nadia Chandra Sekar
- School of Health and Biomedical Sciences, RMIT University, 289 McKimmies Rd, Bundoora, Victoria, 3083, Australia
| | - Peter Thurgood
- School of Engineering, RMIT University, 124 La Trobe St, Melbourne, Victoria, 3001, Australia
| | - Anthony Jaworowski
- School of Health and Biomedical Sciences, RMIT University, 289 McKimmies Rd, Bundoora, Victoria, 3083, Australia
| | - Karlheinz Peter
- School of Health and Biomedical Sciences, RMIT University, 289 McKimmies Rd, Bundoora, Victoria, 3083, Australia.,Baker Heart and Diabetes Institute, 75 Commercial Rd, Melbourne, Victoria, 3004, Australia.,Baker Department of Cardiometabolic Health, University of Melbourne, 30 Flemington Rd, Parkville, 3053, Australia
| | - Sara Baratchi
- School of Health and Biomedical Sciences, RMIT University, 289 McKimmies Rd, Bundoora, Victoria, 3083, Australia.,Baker Heart and Diabetes Institute, 75 Commercial Rd, Melbourne, Victoria, 3004, Australia.,Baker Department of Cardiometabolic Health, University of Melbourne, 30 Flemington Rd, Parkville, 3053, Australia
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8
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Insuela DBR, Ferrero MR, Gonçalves-de-Albuquerque CF, Chaves ADS, da Silva AYO, Castro-Faria-Neto HC, Simões RL, Barja-Fidalgo TC, Silva PMRE, Martins MA, Silva AR, Carvalho VF. Glucagon Reduces Neutrophil Migration and Increases Susceptibility to Sepsis in Diabetic Mice. Front Immunol 2021; 12:633540. [PMID: 34295325 PMCID: PMC8290340 DOI: 10.3389/fimmu.2021.633540] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 06/21/2021] [Indexed: 11/28/2022] Open
Abstract
Sepsis is one of the most common comorbidities observed in diabetic patients, associated with a deficient innate immune response. Recently, we have shown that glucagon possesses anti-inflammatory properties. In this study, we investigated if hyperglucagonemia triggered by diabetes might reduce the migration of neutrophils, increasing sepsis susceptibility. 21 days after diabetes induction by intravenous injection of alloxan, we induced moderate sepsis in Swiss-Webster mice through cecum ligation and puncture (CLP). The glucagon receptor (GcgR) antagonist des-his1-[Glu9]-glucagon amide was injected intraperitoneally 24h and 1h before CLP. We also tested the effect of glucagon on CXCL1/KC-induced neutrophil migration to the peritoneal cavity in mice. Neutrophil chemotaxis in vitro was tested using transwell plates, and the expression of total PKA and phospho-PKA was evaluated by western blot. GcgR antagonist restored neutrophil migration, reduced CFU numbers in the peritoneal cavity and improved survival rate of diabetic mice after CLP procedure, however, the treatment did no alter hyperglycemia, CXCL1/KC plasma levels and blood neutrophilia. In addition, glucagon inhibited CXCL1/KC-induced neutrophil migration to the peritoneal cavity of non-diabetic mice. Glucagon also decreased the chemotaxis of neutrophils triggered by CXCL1/KC, PAF, or fMLP in vitro. The inhibitory action of glucagon occurred in parallel with the reduction of CXCL1/KC-induced actin polymerization in neutrophils in vitro, but not CD11a and CD11b translocation to cell surface. The suppressor effect of glucagon on CXCL1/KC-induced neutrophil chemotaxis in vitro was reversed by pre-treatment with GcgR antagonist and adenylyl cyclase or PKA inhibitors. Glucagon also increased PKA phosphorylation directly in neutrophils in vitro. Furthermore, glucagon impaired zymosan-A-induced ROS production by neutrophils in vitro. Human neutrophil chemotaxis and adherence to endothelial cells in vitro were inhibited by glucagon treatment. According to our results, this inhibition was independent of CD11a and CD11b translocation to neutrophil surface or neutrophil release of CXCL8/IL-8. Altogether, our results suggest that glucagon may be involved in the reduction of neutrophil migration and increased susceptibility to sepsis in diabetic mice. This work collaborates with better understanding of the increased susceptibility and worsening of sepsis in diabetics, which can contribute to the development of new effective therapeutic strategies for diabetic septic patients.
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Affiliation(s)
| | - Maximiliano Ruben Ferrero
- Laboratory of Inflammation, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Cassiano Felippe Gonçalves-de-Albuquerque
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil.,Laboratory of Immunopharmacology, Biomedical Institute, Federal University of the State of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Amanda da Silva Chaves
- Laboratory of Inflammation, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | | | - Hugo Caire Castro-Faria-Neto
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil.,Laboratory of Inflammation, National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Rio de Janeiro, Brazil
| | - Rafael Loureiro Simões
- Laboratory of Cellular and Molecular Pharmacology, Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, Brazil
| | - Thereza Christina Barja-Fidalgo
- Laboratory of Cellular and Molecular Pharmacology, Biology Institute, State University of Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Marco Aurélio Martins
- Laboratory of Inflammation, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil
| | - Adriana Ribeiro Silva
- Laboratory of Immunopharmacology, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil.,Laboratory of Inflammation, National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Rio de Janeiro, Brazil
| | - Vinicius Frias Carvalho
- Laboratory of Inflammation, Oswaldo Cruz Institute, Oswaldo Cruz Foundation (FIOCRUZ), Rio de Janeiro, Brazil.,Laboratory of Inflammation, National Institute of Science and Technology on Neuroimmunomodulation (INCT-NIM), Rio de Janeiro, Brazil
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9
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Ernest James Phillips T, Maguire E. Phosphoinositides: Roles in the Development of Microglial-Mediated Neuroinflammation and Neurodegeneration. Front Cell Neurosci 2021; 15:652593. [PMID: 33841102 PMCID: PMC8032904 DOI: 10.3389/fncel.2021.652593] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 03/08/2021] [Indexed: 12/11/2022] Open
Abstract
Microglia are increasingly recognized as vital players in the pathology of a variety of neurodegenerative conditions including Alzheimer’s (AD) and Parkinson’s (PD) disease. While microglia have a protective role in the brain, their dysfunction can lead to neuroinflammation and contributes to disease progression. Also, a growing body of literature highlights the seven phosphoinositides, or PIPs, as key players in the regulation of microglial-mediated neuroinflammation. These small signaling lipids are phosphorylated derivates of phosphatidylinositol, are enriched in the brain, and have well-established roles in both homeostasis and disease.Disrupted PIP levels and signaling has been detected in a variety of dementias. Moreover, many known AD disease modifiers identified via genetic studies are expressed in microglia and are involved in phospholipid metabolism. One of these, the enzyme PLCγ2 that hydrolyzes the PIP species PI(4,5)P2, displays altered expression in AD and PD and is currently being investigated as a potential therapeutic target.Perhaps unsurprisingly, neurodegenerative conditions exhibiting PIP dyshomeostasis also tend to show alterations in aspects of microglial function regulated by these lipids. In particular, phosphoinositides regulate the activities of proteins and enzymes required for endocytosis, toll-like receptor signaling, purinergic signaling, chemotaxis, and migration, all of which are affected in a variety of neurodegenerative conditions. These functions are crucial to allow microglia to adequately survey the brain and respond appropriately to invading pathogens and other abnormalities, including misfolded proteins. AD and PD therapies are being developed to target many of the above pathways, and although not yet investigated, simultaneous PIP manipulation might enhance the beneficial effects observed. Currently, only limited therapeutics are available for dementia, and although these show some benefits for symptom severity and progression, they are far from curative. Given the importance of microglia and PIPs in dementia development, this review summarizes current research and asks whether we can exploit this information to design more targeted, or perhaps combined, dementia therapeutics. More work is needed to fully characterize the pathways discussed in this review, but given the strength of the current literature, insights in this area could be invaluable for the future of neurodegenerative disease research.
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Affiliation(s)
| | - Emily Maguire
- UK Dementia Research Institute at Cardiff University, Cardiff, United Kingdom
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10
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Cristobal CD, Ye Q, Jo J, Ding X, Wang CY, Cortes D, Chen Z, Lee HK. Daam2 couples translocation and clustering of Wnt receptor signalosomes through Rac1. J Cell Sci 2021; 134:jcs.251140. [PMID: 33310913 DOI: 10.1242/jcs.251140] [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: 07/03/2020] [Accepted: 12/07/2020] [Indexed: 11/20/2022] Open
Abstract
Wnt signaling plays a critical role in development across species and is dysregulated in a host of human diseases. A key step in signal transduction is the formation of Wnt receptor signalosomes, during which a large number of components translocate to the membrane, cluster together and amplify downstream signaling. However, the molecular processes that coordinate these events remain poorly defined. Here, we show that Daam2 regulates canonical Wnt signaling via the PIP2-PIP5K axis through its association with Rac1. Clustering of Daam2-mediated Wnt receptor complexes requires both Rac1 and PIP5K, and PIP5K promotes membrane localization of these complexes in a Rac1-dependent manner. Importantly, the localization of Daam2 complexes and Daam2-mediated canonical Wnt signaling is dependent upon actin polymerization. These studies - in chick spinal cord and human and monkey cell lines - highlight novel roles for Rac1 and the actin cytoskeleton in the regulation of canonical Wnt signaling and define Daam2 as a key scaffolding hub that coordinates membrane translocation and signalosome clustering.
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Affiliation(s)
- Carlo D Cristobal
- Program in Integrative Molecular and Biomedical Sciences, Baylor College of Medicine, Houston, TX 77030, USA
| | - Qi Ye
- Department of Pediatric, Baylor College of Medicine, Houston, TX 77030, USA
| | - Juyeon Jo
- Department of Pediatric, Baylor College of Medicine, Houston, TX 77030, USA
| | - Xiaoyun Ding
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA
| | - Chih-Yen Wang
- Department of Pediatric, Baylor College of Medicine, Houston, TX 77030, USA
| | - Diego Cortes
- Department of Pediatric, Baylor College of Medicine, Houston, TX 77030, USA
| | - Zheng Chen
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX 77030, USA
| | - Hyun Kyoung Lee
- Program in Integrative Molecular and Biomedical Sciences, Baylor College of Medicine, Houston, TX 77030, USA .,Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, USA.,Jan and Dan Duncan Neurological Research Institute, Texas Children's Hospital, Baylor College of Medicine, Houston, TX 77030, USA
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11
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Promoted migration of fibroblast cells on low aspect ratio isotropic nanopore surface by reduced maturation of focal adhesion at peripheral region. Colloids Surf B Biointerfaces 2020; 195:111229. [DOI: 10.1016/j.colsurfb.2020.111229] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2020] [Revised: 06/26/2020] [Accepted: 06/29/2020] [Indexed: 01/08/2023]
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12
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Szlasa W, Zendran I, Zalesińska A, Tarek M, Kulbacka J. Lipid composition of the cancer cell membrane. J Bioenerg Biomembr 2020; 52:321-342. [PMID: 32715369 PMCID: PMC7520422 DOI: 10.1007/s10863-020-09846-4] [Citation(s) in RCA: 177] [Impact Index Per Article: 44.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 07/10/2020] [Indexed: 12/12/2022]
Abstract
Cancer cell possesses numerous adaptations to resist the immune system response and chemotherapy. One of the most significant properties of the neoplastic cells is the altered lipid metabolism, and consequently, the abnormal cell membrane composition. Like in the case of phosphatidylcholine, these changes result in the modulation of certain enzymes and accumulation of energetic material, which could be used for a higher proliferation rate. The changes are so prominent, that some lipids, such as phosphatidylserines, could even be considered as the cancer biomarkers. Additionally, some changes of biophysical properties of cell membranes lead to the higher resistance to chemotherapy, and finally to the disturbances in signalling pathways. Namely, the increased levels of certain lipids, like for instance phosphatidylserine, lead to the attenuation of the immune system response. Also, changes in lipid saturation prevent the cells from demanding conditions of the microenvironment. Particularly interesting is the significance of cell membrane cholesterol content in the modulation of metastasis. This review paper discusses the roles of each lipid type in cancer physiology. The review combined theoretical data with clinical studies to show novel therapeutic options concerning the modulation of cell membranes in oncology.
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Affiliation(s)
- Wojciech Szlasa
- Faculty of Medicine, Wroclaw Medical University, Wrocław, Poland
| | - Iga Zendran
- Faculty of Medicine, Wroclaw Medical University, Wrocław, Poland
| | | | - Mounir Tarek
- Université de Lorraine, CNRS, LPCT, F-54000, Nancy, France
| | - Julita Kulbacka
- Department of Molecular and Cellular Biology, Faculty of Pharmacy, Wroclaw Medical University, Wrocław, Poland.
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13
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Low H, Mukhamedova N, Capettini LDSA, Xia Y, Carmichael I, Cody SH, Huynh K, Ditiatkovski M, Ohkawa R, Bukrinsky M, Meikle PJ, Choi SH, Field S, Miller YI, Sviridov D. Cholesterol Efflux-Independent Modification of Lipid Rafts by AIBP (Apolipoprotein A-I Binding Protein). Arterioscler Thromb Vasc Biol 2020; 40:2346-2359. [PMID: 32787522 PMCID: PMC7530101 DOI: 10.1161/atvbaha.120.315037] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE AIBP (apolipoprotein A-I binding protein) is an effective and selective regulator of lipid rafts modulating many metabolic pathways originating from the rafts, including inflammation. The mechanism of action was suggested to involve stimulation by AIBP of cholesterol efflux, depleting rafts of cholesterol, which is essential for lipid raft integrity. Here we describe a different mechanism contributing to the regulation of lipid rafts by AIBP. Approach and Results: We demonstrate that modulation of rafts by AIBP may not exclusively depend on the rate of cholesterol efflux or presence of the key regulator of the efflux, ABCA1 (ATP-binding cassette transporter A-I). AIBP interacted with phosphatidylinositol 3-phosphate, which was associated with increased abundance and activation of Cdc42 and rearrangement of the actin cytoskeleton. Cytoskeleton rearrangement was accompanied with reduction of the abundance of lipid rafts, without significant changes in the lipid composition of the rafts. The interaction of AIBP with phosphatidylinositol 3-phosphate was blocked by AIBP substrate, NADPH (nicotinamide adenine dinucleotide phosphate), and both NADPH and silencing of Cdc42 interfered with the ability of AIBP to regulate lipid rafts and cholesterol efflux. CONCLUSIONS Our findings indicate that an underlying mechanism of regulation of lipid rafts by AIBP involves PIP-dependent rearrangement of the cytoskeleton.
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Affiliation(s)
- Hann Low
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia (H.L., N.M., K.H., M.D., R.O., P.J.M., D.S.)
| | - Nigora Mukhamedova
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia (H.L., N.M., K.H., M.D., R.O., P.J.M., D.S.)
| | - Luciano Dos Santos Aggum Capettini
- Department of Medicine, University of California San Diego, La Jolla (L.d.S.A.C., Y.X., S.-H.C., S.F., Y.I.M.).,Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Brazil (L.d.S.A.C.)
| | - Yining Xia
- Department of Medicine, University of California San Diego, La Jolla (L.d.S.A.C., Y.X., S.-H.C., S.F., Y.I.M.)
| | - Irena Carmichael
- Department of Monash Micro Imaging, Monash University, Melbourne, VIC, Australia (I.C., S.H.C.)
| | - Stephen H Cody
- Department of Monash Micro Imaging, Monash University, Melbourne, VIC, Australia (I.C., S.H.C.)
| | - Kevin Huynh
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia (H.L., N.M., K.H., M.D., R.O., P.J.M., D.S.)
| | - Michael Ditiatkovski
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia (H.L., N.M., K.H., M.D., R.O., P.J.M., D.S.)
| | - Ryunosuke Ohkawa
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia (H.L., N.M., K.H., M.D., R.O., P.J.M., D.S.).,Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Japan (R.O.)
| | - Michael Bukrinsky
- Department of Microbiology, Immunology and Tropical Medicine, George Washington University School of Medicine and Health Sciences, DC (M.B.)
| | - Peter J Meikle
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia (H.L., N.M., K.H., M.D., R.O., P.J.M., D.S.)
| | - Soo-Ho Choi
- Department of Medicine, University of California San Diego, La Jolla (L.d.S.A.C., Y.X., S.-H.C., S.F., Y.I.M.)
| | - Seth Field
- Department of Medicine, University of California San Diego, La Jolla (L.d.S.A.C., Y.X., S.-H.C., S.F., Y.I.M.)
| | - Yury I Miller
- Department of Medicine, University of California San Diego, La Jolla (L.d.S.A.C., Y.X., S.-H.C., S.F., Y.I.M.)
| | - Dmitri Sviridov
- Baker Heart and Diabetes Institute, Melbourne, VIC, Australia (H.L., N.M., K.H., M.D., R.O., P.J.M., D.S.).,Department of Biochemistry and Molecular Biology, Monash University, Clayton, VIC, Australia (D.S.)
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14
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Abstract
Profilin is a ubiquitously expressed protein well known as a key regulator of actin polymerisation. The actin cytoskeleton is involved in almost all cellular processes including motility, endocytosis, metabolism, signal transduction and gene transcription. Hence, profilin's role in the cell goes beyond its direct and essential function in regulating actin dynamics. This review will focus on the interactions of Profilin 1 and its ligands at the plasma membrane, in the cytoplasm and the nucleus of the cells and the regulation of profilin activity within those cell compartments. We will discuss the interactions of profilin in cell signalling pathways and highlight the importance of the cell context in the multiple functions that this small essential protein has in conjunction with its role in cytoskeletal organisation and dynamics. We will review some of the mechanisms that control profilin expression and the implications of changed expression of profilin in the light of cancer biology and other pathologies.
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15
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Heikenwalder M, Lorentzen A. The role of polarisation of circulating tumour cells in cancer metastasis. Cell Mol Life Sci 2019; 76:3765-3781. [PMID: 31218452 PMCID: PMC6744547 DOI: 10.1007/s00018-019-03169-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2019] [Revised: 04/23/2019] [Accepted: 05/29/2019] [Indexed: 02/06/2023]
Abstract
Metastasis is the spread of cancer cells from a primary tumour to a distant site of the body. Metastasising tumour cells have to survive and readjust to different environments, such as heterogeneous solid tissues and liquid phase in lymph- or blood circulation, which they achieve through a high degree of plasticity that renders them adaptable to varying conditions. One defining characteristic of the metastatic process is the transition of tumour cells between different polarised phenotypes, ranging from differentiated epithelial polarity to migratory front-rear polarity. Here, we review the polarisation types adopted by tumour cells during the metastatic process and describe the recently discovered single-cell polarity in liquid phase observed in circulating tumour cells. We propose that single-cell polarity constitutes a mode of polarisation of the cell cortex that is uncoupled from the intracellular polarisation machinery, which distinguishes single-cell polarity from other types of polarity identified so far. We discuss how single-cell polarity can contribute to tumour metastasis and the therapeutic potential of this new discovery.
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Affiliation(s)
- Mathias Heikenwalder
- Divison of Chronic Inflammation and Cancer, German Cancer Research Center (DKFZ), 69120, Heidelberg, Germany.
| | - Anna Lorentzen
- Department of Molecular Biology and Genetics, Aarhus University, 8000, Aarhus, Denmark.
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16
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Raghu P, Joseph A, Krishnan H, Singh P, Saha S. Phosphoinositides: Regulators of Nervous System Function in Health and Disease. Front Mol Neurosci 2019; 12:208. [PMID: 31507376 PMCID: PMC6716428 DOI: 10.3389/fnmol.2019.00208] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2019] [Accepted: 08/07/2019] [Indexed: 12/11/2022] Open
Abstract
Phosphoinositides, the seven phosphorylated derivatives of phosphatidylinositol have emerged as regulators of key sub-cellular processes such as membrane transport, cytoskeletal function and plasma membrane signaling in eukaryotic cells. All of these processes are also present in the cells that constitute the nervous system of animals and in this setting too, these are likely to tune key aspects of cell biology in relation to the unique structure and function of neurons. Phosphoinositides metabolism and function are mediated by enzymes and proteins that are conserved in evolution, and analysis of knockouts of these in animal models implicate this signaling system in neural function. Most recently, with the advent of human genome analysis, mutations in genes encoding components of the phosphoinositide signaling pathway have been implicated in human diseases although the cell biological basis of disease phenotypes in many cases remains unclear. In this review we evaluate existing evidence for the involvement of phosphoinositide signaling in human nervous system diseases and discuss ways of enhancing our understanding of the role of this pathway in the human nervous system's function in health and disease.
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Affiliation(s)
- Padinjat Raghu
- National Centre for Biological Sciences-TIFR, Bengaluru, India
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17
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Nakada-Tsukui K, Watanabe N, Maehama T, Nozaki T. Phosphatidylinositol Kinases and Phosphatases in Entamoeba histolytica. Front Cell Infect Microbiol 2019; 9:150. [PMID: 31245297 PMCID: PMC6563779 DOI: 10.3389/fcimb.2019.00150] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Accepted: 04/23/2019] [Indexed: 12/11/2022] Open
Abstract
Phosphatidylinositol (PtdIns) metabolism is indispensable in eukaryotes. Phosphoinositides (PIs) are phosphorylated derivatives of PtdIns and consist of seven species generated by reversible phosphorylation of the inositol moieties at the positions 3, 4, and 5. Each of the seven PIs has a unique subcellular and membrane domain distribution. In the enteric protozoan parasite Entamoeba histolytica, it has been previously shown that the PIs phosphatidylinositol 3-phosphate (PtdIns3P), PtdIns(4,5)P2, and PtdIns(3,4,5)P3 are localized to phagosomes/phagocytic cups, plasma membrane, and phagocytic cups, respectively. The localization of these PIs in E. histolytica is similar to that in mammalian cells, suggesting that PIs have orthologous functions in E. histolytica. In contrast, the conservation of the enzymes that metabolize PIs in this organism has not been well-documented. In this review, we summarized the full repertoire of the PI kinases and PI phosphatases found in E. histolytica via a genome-wide survey of the current genomic information. E. histolytica appears to have 10 PI kinases and 23 PI phosphatases. It has a panel of evolutionarily conserved enzymes that generate all the seven PI species. However, class II PI 3-kinases, type II PI 4-kinases, type III PI 5-phosphatases, and PI 4P-specific phosphatases are not present. Additionally, regulatory subunits of class I PI 3-kinases and type III PI 4-kinases have not been identified. Instead, homologs of class I PI 3-kinases and PTEN, a PI 3-phosphatase, exist as multiple isoforms, which likely reflects that elaborate signaling cascades mediated by PtdIns(3,4,5)P3 are present in this organism. There are several enzymes that have the nuclear localization signal: one phosphatidylinositol phosphate (PIP) kinase, two PI 3-phosphatases, and one PI 5-phosphatase; this suggests that PI metabolism also has conserved roles related to nuclear functions in E. histolytica, as it does in model organisms.
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Affiliation(s)
- Kumiko Nakada-Tsukui
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan
| | - Natsuki Watanabe
- Department of Parasitology, National Institute of Infectious Diseases, Tokyo, Japan.,Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
| | - Tomohiko Maehama
- Division of Molecular and Cellular Biology, Graduate School of Medicine, Kobe University, Kobe, Japan
| | - Tomoyoshi Nozaki
- Department of Biomedical Chemistry, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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18
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Liu X, Cao W, Qi J, Li Q, Zhao M, Chen Z, Zhu J, Huang Z, Wu L, Zhang B, Yuan Y, Xing C. Leonurine ameliorates adriamycin-induced podocyte injury via suppression of oxidative stress. Free Radic Res 2018; 52:952-960. [PMID: 30334481 DOI: 10.1080/10715762.2018.1500021] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Leonurine, a major bioactive component from Herba Leonuri, shows therapeutic potential in several diseases, including diabetes, cardiovascular disease, bovine mastitis and depression. In kidney, it was reported that leonurine was performing a protective effect in both acute kidney injury and renal fibrosis mice models. The aim of this study is to investigate the effect of leonurine in podocyte injury. In the mice model of adriamycin (ADR) -induced nephropathy, the application of leonurine significantly prevented early kidney damage, macrophage infiltration and proteinuria. Meanwhile, leonurine suppressed ADR-induced podocyte injury and reactive oxygen species (ROS) production. Consistent to in vivo results, leonurine prevented ADR-induced podocyte injury and ROS production in cultured human podocytes. All these results suggested that leonurine might suppress ADR-induced podocyte injury via inhibiting oxidative stress. Leonurine might be a novel therapeutic drug for prevention of glomerular diseases.
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Affiliation(s)
- Xi Liu
- a Department of Nephrology , the First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University , Nanjing , China
| | - Wei Cao
- a Department of Nephrology , the First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University , Nanjing , China
| | - Jia Qi
- b Department of Pharmacy , Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine , Shanghai , China
| | - Qing Li
- a Department of Nephrology , the First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University , Nanjing , China
| | - Min Zhao
- c Department of Nephrology , Affiliated Nanjing Drum Tower Hospital, Nanjing University School of Medicine , Nanjing , China
| | - Zhuyun Chen
- a Department of Nephrology , the First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University , Nanjing , China
| | - Jingfeng Zhu
- a Department of Nephrology , the First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University , Nanjing , China
| | - Zhimin Huang
- a Department of Nephrology , the First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University , Nanjing , China
| | - Lin Wu
- a Department of Nephrology , the First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University , Nanjing , China
| | - Bo Zhang
- a Department of Nephrology , the First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University , Nanjing , China
| | - Yanggang Yuan
- a Department of Nephrology , the First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University , Nanjing , China
| | - Changying Xing
- a Department of Nephrology , the First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University , Nanjing , China
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19
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Li L, Kołodziej T, Jafari N, Chen J, Zhu H, Rajfur Z, Huang C. Cdk5-mediated phosphorylation regulates phosphatidylinositol 4-phosphate 5-kinase type I γ 90 activity and cell invasion. FASEB J 2018; 33:631-642. [PMID: 30040488 DOI: 10.1096/fj.201800296r] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Phosphatidylinositol 4-phosphate 5-kinase type I γ (PIPKIγ90) regulates cell migration, invasion, and metastasis. However, it is unknown how cellular signals regulate those processes. Here, we show that cyclin-dependent kinase 5 (Cdk5), a protein kinase that regulates cell migration and invasion, phosphorylates PIPKIγ90 at S453, and that Cdk5-mediated PIPKIγ90 phosphorylation is essential for cell invasion. Moreover, Cdk5-mediated phosphorylation down-regulates the activity of PIPKIγ90 and the secretion of fibronectin, an extracellular matrix protein that regulates cell migration and invasion. Furthermore, inhibition of PIPKIγ activity with the chemical inhibitor UNC3230 suppresses fibronectin secretion in a dose-dependent manner, whereas depletion of Cdk5 enhances fibronectin secretion. With total internal reflection fluorescence microscopy, we found that secreted fibronectin appears as round dots, which colocalize with Tks5 and CD9 but not with Zyxin. These data suggest that Cdk5-mediated PIPKIγ90 phosphorylation regulates cell invasion by controlling PIPKIγ90 activity and fibronectin secretion.-Li, L., Kołodziej, T., Jafari, N., Chen, J., Zhu, H., Rajfur, Z., Huang, C. Cdk5-mediated phosphorylation regulates phosphatidylinositol 4-phosphate 5-kinase type I γ 90 activity and cell invasion.
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Affiliation(s)
- Liqing Li
- Markey Cancer Center, University of Kentucky, Lexington, Kentucky, USA
| | - Tomasz Kołodziej
- Markey Cancer Center, University of Kentucky, Lexington, Kentucky, USA.,Faculty of Physics, Astronomy, and Applied Computer Science, Institute of Physics, Jagiellonian University, Krakow, Poland
| | - Naser Jafari
- Markey Cancer Center, University of Kentucky, Lexington, Kentucky, USA
| | - Jing Chen
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, USA; and
| | - Haining Zhu
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, Kentucky, USA; and
| | - Zenon Rajfur
- Faculty of Physics, Astronomy, and Applied Computer Science, Institute of Physics, Jagiellonian University, Krakow, Poland
| | - Cai Huang
- Markey Cancer Center, University of Kentucky, Lexington, Kentucky, USA.,Department of Pharmacology and Nutritional Sciences, University of Kentucky, Lexington, Kentucky, USA
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20
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Scholze MJ, Barbieux KS, De Simone A, Boumasmoud M, Süess CCN, Wang R, Gönczy P. PI(4,5)P 2 forms dynamic cortical structures and directs actin distribution as well as polarity in Caenorhabditis elegans embryos. Development 2018; 145:dev.164988. [PMID: 29724757 DOI: 10.1242/dev.164988] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 04/19/2018] [Indexed: 01/25/2023]
Abstract
Asymmetric division is crucial for embryonic development and stem cell lineages. In the one-cell Caenorhabditis elegans embryo, a contractile cortical actomyosin network contributes to asymmetric division by segregating partitioning-defective (PAR) proteins to discrete cortical domains. In the current study, we found that the plasma membrane lipid phosphatidylinositol 4,5-bisphosphate (PIP2) localizes to polarized dynamic structures in C. elegans zygotes, distributing in a PAR-dependent manner along the anterior-posterior (A-P) embryonic axis. PIP2 cortical structures overlap with F-actin, and coincide with the actin regulators RHO-1 and CDC-42, as well as ECT-2. Particle image velocimetry analysis revealed that PIP2 and F-actin cortical movements are coupled, with PIP2 structures moving slightly ahead of F-actin. Importantly, we established that PIP2 cortical structure formation and movement is actin dependent. Moreover, we found that decreasing or increasing the level of PIP2 resulted in severe F-actin disorganization, revealing interdependence between these components. Furthermore, we determined that PIP2 and F-actin regulate the sizing of PAR cortical domains, including during the maintenance phase of polarization. Overall, our work establishes that a lipid membrane component, PIP2, modulates actin organization and cell polarity in C. elegans embryos.
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Affiliation(s)
- Melina J Scholze
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (EPFL), CH-1015 Lausanne, Switzerland
| | - Kévin S Barbieux
- Geodetic Engineering Laboratory (TOPO), Swiss Federal Institute of Technology (EPFL), Environmental Engineering Institute (IIE), CH-1015 Lausanne, Switzerland
| | - Alessandro De Simone
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (EPFL), CH-1015 Lausanne, Switzerland
| | - Mathilde Boumasmoud
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (EPFL), CH-1015 Lausanne, Switzerland
| | - Camille C N Süess
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (EPFL), CH-1015 Lausanne, Switzerland
| | - Ruijia Wang
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (EPFL), CH-1015 Lausanne, Switzerland
| | - Pierre Gönczy
- Swiss Institute for Experimental Cancer Research (ISREC), School of Life Sciences, Swiss Federal Institute of Technology (EPFL), CH-1015 Lausanne, Switzerland
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21
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Mkrtschjan MA, Gaikwad SB, Kappenman KJ, Solís C, Dommaraju S, Le LV, Desai TA, Russell B. Lipid signaling affects primary fibroblast collective migration and anchorage in response to stiffness and microtopography. J Cell Physiol 2017; 233:3672-3683. [PMID: 29034471 DOI: 10.1002/jcp.26236] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 10/05/2017] [Indexed: 12/13/2022]
Abstract
Cell migration is regulated by several mechanotransduction pathways, which consist of sensing and converting mechanical microenvironmental cues to internal biochemical cellular signals, such as protein phosphorylation and lipid signaling. While there has been significant progress in understanding protein changes in the context of mechanotransduction, lipid signaling is more difficult to investigate. In this study, physical cues of stiffness (10, 100, 400 kPa, and glass), and microrod or micropost topography were manipulated in order to reprogram primary fibroblasts and assess the effects of lipid signaling on the actin cytoskeleton. In an in vitro wound closure assay, primary cardiac fibroblast migration velocity was significantly higher on soft polymeric substrata. Modulation of PIP2 availability through neomycin treatment nearly doubled migration velocity on 10 kPa substrata, with significant increases on all stiffnesses. The distance between focal adhesions and the lamellar membrane (using wortmannin treatment to increase PIP2 via PI3K inhibition) was significantly shortest compared to untreated fibroblasts grown on the same surface. PIP2 localized to the leading edge of migrating fibroblasts more prominently in neomycin-treated cells. The membrane-bound protein, lamellipodin, did not vary under any condition. Additionally, fifteen micron-high micropost topography, which blocks migration, concentrates PIP2 near to the post. Actin dynamics within stress fibers, measured by fluorescence recovery after photobleaching, was not significantly different with stiffness, microtopography, nor with drug treatment. PIP2-modulating drugs delivered from microrod structures also affected migration velocity. Thus, manipulation of the microenvironment and lipid signaling regulatory drugs might be beneficial in improving therapeutics geared toward wound healing.
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Affiliation(s)
- Michael A Mkrtschjan
- Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois
| | - Snehal B Gaikwad
- Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois
| | - Kevin J Kappenman
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, Illinois
| | - Christopher Solís
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, Illinois
| | - Sagar Dommaraju
- Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, Illinois
| | - Long V Le
- Department of Bioengineering and Therapeutic Sciences, University of California at San Francisco, San Francisco, California
| | - Tejal A Desai
- Department of Bioengineering and Therapeutic Sciences, University of California at San Francisco, San Francisco, California
| | - Brenda Russell
- Department of Bioengineering, University of Illinois at Chicago, Chicago, Illinois.,Department of Physiology and Biophysics, University of Illinois at Chicago, Chicago, Illinois
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22
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Mohan K, Nosbisch JL, Elston TC, Bear JE, Haugh JM. A Reaction-Diffusion Model Explains Amplification of the PLC/PKC Pathway in Fibroblast Chemotaxis. Biophys J 2017; 113:185-194. [PMID: 28700916 DOI: 10.1016/j.bpj.2017.05.035] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Revised: 05/18/2017] [Accepted: 05/25/2017] [Indexed: 12/20/2022] Open
Abstract
During the proliferative phase of cutaneous wound healing, dermal fibroblasts are recruited into the clotted wound by a concentration gradient of platelet-derived growth factor (PDGF), together with other spatial cues. Despite the importance of this chemotactic process, the mechanisms controlling the directed migration of slow-moving mesenchymal cells such as fibroblasts are not well understood. Here, we develop and analyze a reaction-diffusion model of phospholipase C/protein kinase C (PKC) signaling, which was recently identified as a requisite PDGF-gradient-sensing pathway, with the goal of identifying mechanisms that can amplify its sensitivity in the shallow external gradients typical of chemotaxis experiments. We show that phosphorylation of myristoylated alanine-rich C kinase substrate by membrane-localized PKC constitutes a positive feedback that is sufficient for local pathway amplification. The release of phosphorylated myristoylated alanine-rich C kinase substrate and its subsequent diffusion and dephosphorylation in the cytosol also serves to suppress the pathway in down-gradient regions of the cell. By itself, this mechanism only weakly amplifies signaling in a shallow PDGF gradient, but it synergizes with other feedback mechanisms to enhance amplification. This model offers a framework for a mechanistic understanding of phospholipase C/PKC signaling in chemotactic gradient sensing and can guide the design of experiments to assess the roles of putative feedback loops.
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Affiliation(s)
- Krithika Mohan
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina
| | - Jamie L Nosbisch
- Biomathematics Graduate Program, North Carolina State University, Raleigh, North Carolina
| | - Timothy C Elston
- Department of Pharmacology, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - James E Bear
- Department of Cell Biology and Physiology, Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Jason M Haugh
- Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, North Carolina.
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23
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Verkhovsky AB. The mechanisms of spatial and temporal patterning of cell-edge dynamics. Curr Opin Cell Biol 2015; 36:113-21. [PMID: 26432504 DOI: 10.1016/j.ceb.2015.09.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Revised: 09/11/2015] [Accepted: 09/11/2015] [Indexed: 01/14/2023]
Abstract
Adherent cells migrate and change their shape by means of protrusion and retraction at their edges. When and where these activities occur defines the shape of the cell and the way it moves. Despite a great deal of knowledge about the structural organization, components, and biochemical reactions involved in protrusion and retraction, the origins of their spatial and temporal patterns are still poorly understood. Chemical signaling circuitry is believed to be an important source of patterning, but recent studies highlighted mechanisms based on physical forces, motion, and mechanical feedback.
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Affiliation(s)
- Alexander B Verkhovsky
- Laboratory of Physics of Living Matter, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
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24
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Leondaritis G, Eickholt BJ. Short Lives with Long-Lasting Effects: Filopodia Protrusions in Neuronal Branching Morphogenesis. PLoS Biol 2015; 13:e1002241. [PMID: 26334727 PMCID: PMC4559444 DOI: 10.1371/journal.pbio.1002241] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The branching behaviors of both dendrites and axons are part of a neuronal maturation process initiated by the generation of small and transient membrane protrusions. These are highly dynamic, actin-enriched structures, collectively called filopodia, which can mature in neurons to form stable branches. Consequently, the generation of filopodia protrusions is crucial during the formation of neuronal circuits and involves the precise control of an interplay between the plasma membrane and actin dynamics. In this issue of PLOS Biology, Hou and colleagues identify a Ca2+/CaM-dependent molecular machinery in dendrites that ensures proper targeting of branch formation by activation of the actin nucleator Cobl. A new study provides novel insight into how calcium signalling can control the branching of dendrites during nervous system development.
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Affiliation(s)
- George Leondaritis
- Department of Pharmacology, Medical School, University of Ioannina, Ioannina, Greece
| | - Britta Johanna Eickholt
- Institute of Biochemistry & Neuro Cure Cluster of Excellence, Charité – Universitätsmedizin Berlin, Berlin, Germany
- * E-mail:
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25
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Detchokul S, Frauman AG. Editorial: cell movement. Br J Pharmacol 2015; 171:5459-61. [PMID: 25442220 DOI: 10.1111/bph.12849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
UNLABELLED Cell movement is a fundamental process of normal cellular physiology and pathophysiology. Abnormal regulation of cell migration is a common denominator of many medical disorders, including cancer metastasis, autoimmune disease and inflammation. Increased interest in the targeting of cell migration and invasion, which has potential for therapeutic intervention in many diseases are behind this special themed issue. Thus, the focus of this issue is centred on the control of cellular cytoskeletal dynamics and cellular or tissue microenvironment sensors. Novel therapeutic opportunities targeting regulation of cell migration are discussed including the emerging roles of tetraspanins, phosphoinositides, transient receptor potential cation channels, stromal interaction molecules and calcium release-activated calcium modulators. Better understanding of these regulatory factors will hopefully bring greater attention to strategically targeting aberrant cell migration, which has many therapeutic implications for common human diseases. LINKED ARTICLES This article is part of a themed section on Cytoskeleton, Extracellular Matrix, Cell Migration, Wound Healing and Related Topics. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-24
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Affiliation(s)
- S Detchokul
- Clinical Pharmacology and Therapeutics Unit, Department of Medicine, The University of Melbourne, Heidelberg, VIC, Australia
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26
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Curthoys NM, Parent M, Mlodzianoski M, Nelson AJ, Lilieholm J, Butler MB, Valles M, Hess ST. Dances with Membranes: Breakthroughs from Super-resolution Imaging. CURRENT TOPICS IN MEMBRANES 2015; 75:59-123. [PMID: 26015281 PMCID: PMC5584789 DOI: 10.1016/bs.ctm.2015.03.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Biological membrane organization mediates numerous cellular functions and has also been connected with an immense number of human diseases. However, until recently, experimental methodologies have been unable to directly visualize the nanoscale details of biological membranes, particularly in intact living cells. Numerous models explaining membrane organization have been proposed, but testing those models has required indirect methods; the desire to directly image proteins and lipids in living cell membranes is a strong motivation for the advancement of technology. The development of super-resolution microscopy has provided powerful tools for quantification of membrane organization at the level of individual proteins and lipids, and many of these tools are compatible with living cells. Previously inaccessible questions are now being addressed, and the field of membrane biology is developing rapidly. This chapter discusses how the development of super-resolution microscopy has led to fundamental advances in the field of biological membrane organization. We summarize the history and some models explaining how proteins are organized in cell membranes, and give an overview of various super-resolution techniques and methods of quantifying super-resolution data. We discuss the application of super-resolution techniques to membrane biology in general, and also with specific reference to the fields of actin and actin-binding proteins, virus infection, mitochondria, immune cell biology, and phosphoinositide signaling. Finally, we present our hopes and expectations for the future of super-resolution microscopy in the field of membrane biology.
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Affiliation(s)
- Nikki M. Curthoys
- Department of Physics and Astronomy, University of Maine, Orono, ME, USA
| | - Matthew Parent
- Department of Physics and Astronomy, University of Maine, Orono, ME, USA
| | | | - Andrew J. Nelson
- Department of Physics and Astronomy, University of Maine, Orono, ME, USA
| | - Jennifer Lilieholm
- Department of Physics and Astronomy, University of Maine, Orono, ME, USA
| | - Michael B. Butler
- Department of Physics and Astronomy, University of Maine, Orono, ME, USA
| | - Matthew Valles
- Department of Physics and Astronomy, University of Maine, Orono, ME, USA
| | - Samuel T. Hess
- Department of Physics and Astronomy, University of Maine, Orono, ME, USA
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