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Mallik B, Bhat S, Kumar V. Role of Bin‐Amphiphysin‐Rvs (BAR) domain proteins in mediating neuronal signaling and disease. Synapse 2022; 76:e22248. [DOI: 10.1002/syn.22248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 05/13/2022] [Accepted: 07/18/2022] [Indexed: 11/06/2022]
Affiliation(s)
- Bhagaban Mallik
- Department of Biological Sciences Indian Institute of Science Education and Research (IISER) Bhopal Indore Bypass Road Bhopal Madhya Pradesh 462 066 India
| | - Sajad Bhat
- Department of Biological Sciences Indian Institute of Science Education and Research (IISER) Bhopal Indore Bypass Road Bhopal Madhya Pradesh 462 066 India
| | - Vimlesh Kumar
- Department of Biological Sciences Indian Institute of Science Education and Research (IISER) Bhopal Indore Bypass Road Bhopal Madhya Pradesh 462 066 India
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2
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Chatzi C, Westbrook GL. Revisiting I-BAR Proteins at Central Synapses. Front Neural Circuits 2022; 15:787436. [PMID: 34975417 PMCID: PMC8716821 DOI: 10.3389/fncir.2021.787436] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 11/08/2021] [Indexed: 01/30/2023] Open
Abstract
Dendritic spines, the distinctive postsynaptic feature of central nervous system (CNS) excitatory synapses, have been studied extensively as electrical and chemical compartments, as well as scaffolds for receptor cycling and positioning of signaling molecules. The dynamics of the shape, number, and molecular composition of spines, and how they are regulated by neural activity, are critically important in synaptic efficacy, synaptic plasticity, and ultimately learning and memory. Dendritic spines originate as outward protrusions of the cell membrane, but this aspect of spine formation and stabilization has not been a major focus of investigation compared to studies of membrane protrusions in non-neuronal cells. We review here one family of proteins involved in membrane curvature at synapses, the BAR (Bin-Amphiphysin-Rvs) domain proteins. The subfamily of inverse BAR (I-BAR) proteins sense and introduce outward membrane curvature, and serve as bridges between the cell membrane and the cytoskeleton. We focus on three I-BAR domain proteins that are expressed in the central nervous system: Mtss2, MIM, and IRSp53 that promote negative, concave curvature based on their ability to self-associate. Recent studies suggest that each has distinct functions in synapse formation and synaptic plasticity. The action of I-BARs is also shaped by crosstalk with other signaling components, forming signaling platforms that can function in a circuit-dependent manner. We discuss another potentially important feature-the ability of some BAR domain proteins to impact the function of other family members by heterooligomerization. Understanding the spatiotemporal resolution of synaptic I-BAR protein expression and their interactions should provide insights into the interplay between activity-dependent neural plasticity and network rewiring in the CNS.
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Affiliation(s)
- Christina Chatzi
- Vollum Institute, Oregon Health and Science University, Portland, OR, United States
| | - Gary L Westbrook
- Vollum Institute, Oregon Health and Science University, Portland, OR, United States
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3
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Khanal P, Hotulainen P. Dendritic Spine Initiation in Brain Development, Learning and Diseases and Impact of BAR-Domain Proteins. Cells 2021; 10:cells10092392. [PMID: 34572042 PMCID: PMC8468246 DOI: 10.3390/cells10092392] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 09/08/2021] [Accepted: 09/09/2021] [Indexed: 02/08/2023] Open
Abstract
Dendritic spines are small, bulbous protrusions along neuronal dendrites where most of the excitatory synapses are located. Dendritic spine density in normal human brain increases rapidly before and after birth achieving the highest density around 2-8 years. Density decreases during adolescence, reaching a stable level in adulthood. The changes in dendritic spines are considered structural correlates for synaptic plasticity as well as the basis of experience-dependent remodeling of neuronal circuits. Alterations in spine density correspond to aberrant brain function observed in various neurodevelopmental and neuropsychiatric disorders. Dendritic spine initiation affects spine density. In this review, we discuss the importance of spine initiation in brain development, learning, and potential complications resulting from altered spine initiation in neurological diseases. Current literature shows that two Bin Amphiphysin Rvs (BAR) domain-containing proteins, MIM/Mtss1 and SrGAP3, are involved in spine initiation. We review existing literature and open databases to discuss whether other BAR-domain proteins could also take part in spine initiation. Finally, we discuss the potential molecular mechanisms on how BAR-domain proteins could regulate spine initiation.
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Affiliation(s)
- Pushpa Khanal
- Minerva Foundation Institute for Medical Research, Tukholmankatu 8, 00290 Helsinki, Finland;
- HiLIFE-Neuroscience Center, University of Helsinki, 00014 Helsinki, Finland
| | - Pirta Hotulainen
- Minerva Foundation Institute for Medical Research, Tukholmankatu 8, 00290 Helsinki, Finland;
- Correspondence:
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4
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Izadi M, Seemann E, Schlobinski D, Schwintzer L, Qualmann B, Kessels MM. Functional interdependence of the actin nucleator Cobl and Cobl-like in dendritic arbor development. eLife 2021; 10:67718. [PMID: 34264190 PMCID: PMC8282341 DOI: 10.7554/elife.67718] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 06/30/2021] [Indexed: 12/14/2022] Open
Abstract
Local actin filament formation is indispensable for development of the dendritic arbor of neurons. We show that, surprisingly, the action of single actin filament-promoting factors was insufficient for powering dendritogenesis. Instead, this required the actin nucleator Cobl and its only evolutionary distant ancestor Cobl-like acting interdependently. This coordination between Cobl-like and Cobl was achieved by physical linkage by syndapins. Syndapin I formed nanodomains at convex plasma membrane areas at the base of protrusive structures and interacted with three motifs in Cobl-like, one of which was Ca2+/calmodulin-regulated. Consistently, syndapin I, Cobl-like’s newly identified N terminal calmodulin-binding site and the single Ca2+/calmodulin-responsive syndapin-binding motif all were critical for Cobl-like’s functions. In dendritic arbor development, local Ca2+/CaM-controlled actin dynamics thus relies on regulated and physically coordinated interactions of different F-actin formation-promoting factors and only together they have the power to bring about the sophisticated neuronal morphologies required for neuronal network formation in mammals.
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Affiliation(s)
- Maryam Izadi
- Institute of Biochemistry I, Jena University Hospital/Friedrich-Schiller-University Jena, Jena, Germany
| | - Eric Seemann
- Institute of Biochemistry I, Jena University Hospital/Friedrich-Schiller-University Jena, Jena, Germany
| | - Dirk Schlobinski
- Institute of Biochemistry I, Jena University Hospital/Friedrich-Schiller-University Jena, Jena, Germany
| | - Lukas Schwintzer
- Institute of Biochemistry I, Jena University Hospital/Friedrich-Schiller-University Jena, Jena, Germany
| | - Britta Qualmann
- Institute of Biochemistry I, Jena University Hospital/Friedrich-Schiller-University Jena, Jena, Germany
| | - Michael M Kessels
- Institute of Biochemistry I, Jena University Hospital/Friedrich-Schiller-University Jena, Jena, Germany
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5
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Alimohamadi H, Bell MK, Halpain S, Rangamani P. Mechanical Principles Governing the Shapes of Dendritic Spines. Front Physiol 2021; 12:657074. [PMID: 34220531 PMCID: PMC8242199 DOI: 10.3389/fphys.2021.657074] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Accepted: 05/13/2021] [Indexed: 02/04/2023] Open
Abstract
Dendritic spines are small, bulbous protrusions along the dendrites of neurons and are sites of excitatory postsynaptic activity. The morphology of spines has been implicated in their function in synaptic plasticity and their shapes have been well-characterized, but the potential mechanics underlying their shape development and maintenance have not yet been fully understood. In this work, we explore the mechanical principles that could underlie specific shapes using a minimal biophysical model of membrane-actin interactions. Using this model, we first identify the possible force regimes that give rise to the classic spine shapes-stubby, filopodia, thin, and mushroom-shaped spines. We also use this model to investigate how the spine neck might be stabilized using periodic rings of actin or associated proteins. Finally, we use this model to predict that the cooperation between force generation and ring structures can regulate the energy landscape of spine shapes across a wide range of tensions. Thus, our study provides insights into how mechanical aspects of actin-mediated force generation and tension can play critical roles in spine shape maintenance.
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Affiliation(s)
- Haleh Alimohamadi
- Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, CA, United States
| | - Miriam K. Bell
- Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, CA, United States
| | - Shelley Halpain
- Sanford Consortium for Regenerative Medicine, La Jolla, CA, United States
- Section of Neurobiology, Division of Biological Sciences, University of California, San Diego, La Jolla, CA, United States
| | - Padmini Rangamani
- Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, CA, United States
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6
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Regulation of actin dynamics in dendritic spines: Nanostructure, molecular mobility, and signaling mechanisms. Mol Cell Neurosci 2020; 109:103564. [DOI: 10.1016/j.mcn.2020.103564] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Accepted: 10/04/2020] [Indexed: 12/16/2022] Open
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7
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Kessels MM, Qualmann B. Interplay between membrane curvature and the actin cytoskeleton. Curr Opin Cell Biol 2020; 68:10-19. [PMID: 32927373 DOI: 10.1016/j.ceb.2020.08.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 08/10/2020] [Accepted: 08/11/2020] [Indexed: 12/26/2022]
Abstract
An intimate interplay of the plasma membrane with curvature-sensing and curvature-inducing proteins would allow for defining specific sites or nanodomains of action at the plasma membrane, for example, for protrusion, invagination, and polarization. In addition, such connections are predestined to ensure spatial and temporal order and sequences. The combined forces of membrane shapers and the cortical actin cytoskeleton might hereby in particular be required to overcome the strong resistance against membrane rearrangements in case of high plasma membrane tension or cellular turgor. Interestingly, also the opposite might be necessary, the inhibition of both membrane shapers and cytoskeletal reinforcement structures to relieve membrane tension to protect cells from membrane damage and rupturing during mechanical stress. In this review article, we discuss recent conceptual advances enlightening the interplay of plasma membrane curvature and the cortical actin cytoskeleton during endocytosis, modulations of membrane tensions, and the shaping of entire cells.
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Affiliation(s)
- Michael M Kessels
- Institute of Biochemistry I, Jena University Hospital, Friedrich Schiller University Jena, Nonnenplan 2-4, 07743, Jena, Germany
| | - Britta Qualmann
- Institute of Biochemistry I, Jena University Hospital, Friedrich Schiller University Jena, Nonnenplan 2-4, 07743, Jena, Germany.
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8
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Chen PW, Billington N, Maron BY, Sload JA, Chinthalapudi K, Heissler SM. The BAR domain of the Arf GTPase-activating protein ASAP1 directly binds actin filaments. J Biol Chem 2020; 295:11303-11315. [PMID: 32444496 DOI: 10.1074/jbc.ra119.009903] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Revised: 05/13/2020] [Indexed: 12/11/2022] Open
Abstract
The Arf GTPase-activating protein (Arf GAP) with SH3 domain, ankyrin repeat and PH domain 1 (ASAP1) establishes a connection between the cell membrane and the cortical actin cytoskeleton. The formation, maintenance, and turnover of actin filaments and bundles in the actin cortex are important for cell adhesion, invasion, and migration. Here, using actin cosedimentation, polymerization, and depolymerization assays, along with total internal reflection fluorescence (TIRF), confocal, and EM analyses, we show that the N-terminal N-BAR domain of ASAP1 directly binds to F-actin. We found that ASAP1 homodimerization aligns F-actin in predominantly unipolar bundles and stabilizes them against depolymerization. Furthermore, the ASAP1 N-BAR domain moderately reduced the spontaneous polymerization of G-actin. The overexpression of the ASAP1 BAR-PH tandem domain in fibroblasts induced the formation of actin-filled projections more effectively than did full-length ASAP1. An ASAP1 construct that lacked the N-BAR domain failed to induce cellular projections. Our results suggest that ASAP1 regulates the dynamics and the formation of higher-order actin structures, possibly through direct binding to F-actin via its N-BAR domain. We propose that ASAP1 is a hub protein for dynamic protein-protein interactions in mechanosensitive structures, such as focal adhesions, invadopodia, and podosomes, that are directly implicated in oncogenic events. The effect of ASAP1 on actin dynamics puts a spotlight on its function as a central signaling molecule that regulates the dynamics of the actin cytoskeleton by transmitting signals from the plasma membrane.
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Affiliation(s)
- Pei-Wen Chen
- Department of Biology, Williams College, Williamstown, Massachusetts, USA
| | - Neil Billington
- Laboratory of Molecular Physiology, National Heart, Lung, and Blood Institute, Bethesda, Maryland, USA
| | - Ben Y Maron
- Department of Biology, Williams College, Williamstown, Massachusetts, USA
| | - Jeffrey A Sload
- Department of Biology, Williams College, Williamstown, Massachusetts, USA
| | - Krishna Chinthalapudi
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
| | - Sarah M Heissler
- Department of Physiology and Cell Biology, Dorothy M. Davis Heart and Lung Research Institute, The Ohio State University Wexner Medical Center, Columbus, Ohio, USA
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9
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Seemann E, Kessels MM, Qualmann B. Freeze-Fracture Replica Immunolabeling of Cryopreserved Membrane Compartments, Cultured Cells and Tissues. Methods Mol Biol 2020; 2169:11-25. [PMID: 32548815 DOI: 10.1007/978-1-0716-0732-9_2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Membrane topology information and views of membrane-embedded protein complexes promote our understanding of membrane organization and cell biological function involving membrane compartments. Freeze-fracturing of biological membranes offers both stunning views onto integral membrane proteins and perpendicular views over wide areas of the membrane at electron microscopical resolution. This information is directly assessable for 3D analyses and quantitative analyses of the distribution of components within the membrane if it were possible to specifically detect the components of interest in the membranes. Freeze-fracture replica immunolabeling (FRIL) achieves just that. In addition, FRIL preserves antigens in their genuine cellular context free of artifacts of chemical fixation, as FRIL uses chemically unfixed cellular samples that are rapidly cryofixed. In principle, the method is not limited to integral proteins spanning the membrane. Theoretically, all membrane components should be addressable as long as they are antigenic, embedded into at least one membrane leaflet, and accessible for immunolabeling from either the intracellular or the extracellular side. Consistently, integral proteins spanning both leaflets and only partially inserted membrane proteins have been successfully identified and studied for their molecular organization and distribution in the membrane and/or in relationship to specialized membrane domains. Here we describe the freeze-fracturing of both cultured cells and tissues and the sample preparations that allowed for a successful immunogold-labeling of caveolin1 and caveolin3 or even for double-immunolabelings of caveolins with members of the syndapin family of membrane-associating and -shaping BAR domain proteins as well as with cavin 1. For this purpose samples are cryopreserved, fractured, and replicated. We also describe how the obtained stabilized membrane fractures are then cleaned to remove all loosely attached material and immunogold labeled to finally be viewed by transmission electron microscopy.
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Affiliation(s)
- Eric Seemann
- Institute for Biochemistry I, Jena University Hospital - Friedrich Schiller University Jena, Jena, Germany
| | - Michael M Kessels
- Institute for Biochemistry I, Jena University Hospital - Friedrich Schiller University Jena, Jena, Germany.
| | - Britta Qualmann
- Institute for Biochemistry I, Jena University Hospital - Friedrich Schiller University Jena, Jena, Germany.
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10
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Gasilina A, Vitali T, Luo R, Jian X, Randazzo PA. The ArfGAP ASAP1 Controls Actin Stress Fiber Organization via Its N-BAR Domain. iScience 2019; 22:166-180. [PMID: 31785555 PMCID: PMC6889188 DOI: 10.1016/j.isci.2019.11.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 09/30/2019] [Accepted: 11/06/2019] [Indexed: 12/11/2022] Open
Abstract
ASAP1 is a multi-domain ArfGAP that controls cell migration, spreading, and focal adhesion dynamics. Although its GAP activity contributes to remodeling of the actin cytoskeleton, it does not fully explain all cellular functions of ASAP1. Here we find that ASAP1 regulates actin filament assembly directly through its N-BAR domain and controls stress fiber maintenance. ASAP1 depletion caused defects in stress fiber organization. Conversely, overexpression of ASAP1 enhanced actin remodeling. The BAR-PH fragment was sufficient to affect actin. ASAP1 with the BAR domain replaced with the BAR domain of the related ACAP1 did not affect actin. The BAR-PH tandem of ASAP1 bound and bundled actin filaments directly, whereas the presence of the ArfGAP and the C-terminal linker/SH3 domain reduced binding and bundling of filaments by BAR-PH. Together these data provide evidence that ASAP1 may regulate the actin cytoskeleton through direct interaction of the BAR-PH domain with actin filaments.
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Affiliation(s)
- Anjelika Gasilina
- Section on Regulation of Ras Superfamily, Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bldg. 37, Rm. 2042, Bethesda, MD 20892, USA; Department of Biochemistry and Molecular & Cellular Biology, Georgetown University Medical Center, Washington, DC 20007, USA
| | - Teresa Vitali
- Section on Regulation of Ras Superfamily, Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bldg. 37, Rm. 2042, Bethesda, MD 20892, USA
| | - Ruibai Luo
- Section on Regulation of Ras Superfamily, Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bldg. 37, Rm. 2042, Bethesda, MD 20892, USA
| | - Xiaoying Jian
- Section on Regulation of Ras Superfamily, Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bldg. 37, Rm. 2042, Bethesda, MD 20892, USA
| | - Paul A Randazzo
- Section on Regulation of Ras Superfamily, Laboratory of Cellular and Molecular Biology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bldg. 37, Rm. 2042, Bethesda, MD 20892, USA.
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11
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Abstract
Cell-cell junctions are specializations of the plasma membrane responsible for physically integrating cells into tissues. We are now beginning to appreciate the diverse impacts that mechanical forces exert upon the integrity and function of these junctions. Currently, this is best understood for cadherin-based adherens junctions in epithelia and endothelia, where cell-cell adhesion couples the contractile cytoskeletons of cells together to generate tissue-scale tension. Junctional tension participates in morphogenesis and tissue homeostasis. Changes in tension can also be detected by mechanotransduction pathways that allow cells to communicate with each other. In this review, we discuss progress in characterising the forces present at junctions in physiological conditions; the cellular mechanisms that generate intrinsic tension and detect changes in tension; and, finally, we consider how tissue integrity is maintained in the face of junctional stresses.
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12
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Ziegler AB, Tavosanis G. Glycerophospholipids – Emerging players in neuronal dendrite branching and outgrowth. Dev Biol 2019; 451:25-34. [DOI: 10.1016/j.ydbio.2018.12.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 11/25/2018] [Accepted: 12/11/2018] [Indexed: 01/12/2023]
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13
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Kast DJ, Dominguez R. Mechanism of IRSp53 inhibition by 14-3-3. Nat Commun 2019; 10:483. [PMID: 30696821 PMCID: PMC6351565 DOI: 10.1038/s41467-019-08317-8] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 12/17/2018] [Indexed: 12/26/2022] Open
Abstract
Filopodia are precursors of dendritic spines and polarized cell migration. The I-BAR-domain protein IRSp53 is a key regulator of filopodia dynamics that couples Rho-GTPase signaling to cytoskeleton and membrane remodeling, playing essential roles in neuronal development and cell motility. Here, we describe the structural-functional basis for 14-3-3-dependent inhibition of IRSp53. Phosphoproteomics, quantitative binding and crystallographic studies demonstrate that 14-3-3 binds to two pairs of phosphorylation sites in IRSp53. Using bicistronic expression, we obtain an IRSp53 heterodimer in which only one subunit is phosphorylated, and show that each subunit of IRSp53 independently binds one 14-3-3 dimer. A FRET-sensor assay using natively phosphorylated IRSp53 reveals opposite conformational changes upon binding of activatory (Cdc42, Eps8) or inhibitory (14-3-3) inputs. Finally, we show that 14-3-3 inhibits IRSp53 binding to membranes. Collectively, our findings support a mechanism whereby phosphorylation-dependent inhibition of IRSp53 by 14-3-3 counters membrane binding and interactions with Cdc42 and downstream cytoskeletal effectors. IRSp53 is a key regulator of filopodia formation and cell migration. Here, the authors elucidate a mechanism of phosphorylation-dependent inhibition of IRSp53 by 14-3-3, which impedes the interactions of IRSp53 with membranes and downstream cytoskeletal effectors.
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Affiliation(s)
- David J Kast
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.,Department of Cell Biology and Physiology, Washington University, St. Louis, MO, 63110, USA
| | - Roberto Dominguez
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
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14
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BAR domain proteins-a linkage between cellular membranes, signaling pathways, and the actin cytoskeleton. Biophys Rev 2018; 10:1587-1604. [PMID: 30456600 DOI: 10.1007/s12551-018-0467-7] [Citation(s) in RCA: 79] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 10/17/2018] [Indexed: 12/23/2022] Open
Abstract
Actin filament assembly typically occurs in association with cellular membranes. A large number of proteins sit at the interface between actin networks and membranes, playing diverse roles such as initiation of actin polymerization, modulation of membrane curvature, and signaling. Bin/Amphiphysin/Rvs (BAR) domain proteins have been implicated in all of these functions. The BAR domain family of proteins comprises a diverse group of multi-functional effectors, characterized by their modular architecture. In addition to the membrane-curvature sensing/inducing BAR domain module, which also mediates antiparallel dimerization, most contain auxiliary domains implicated in protein-protein and/or protein-membrane interactions, including SH3, PX, PH, RhoGEF, and RhoGAP domains. The shape of the BAR domain itself varies, resulting in three major subfamilies: the classical crescent-shaped BAR, the more extended and less curved F-BAR, and the inverse curvature I-BAR subfamilies. Most members of this family have been implicated in cellular functions that require dynamic remodeling of the actin cytoskeleton, such as endocytosis, organelle trafficking, cell motility, and T-tubule biogenesis in muscle cells. Here, we review the structure and function of mammalian BAR domain proteins and the many ways in which they are interconnected with the actin cytoskeleton.
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15
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Direct effects of Ca2+/calmodulin on actin filament formation. Biochem Biophys Res Commun 2018; 506:355-360. [DOI: 10.1016/j.bbrc.2018.07.159] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 07/31/2018] [Indexed: 01/06/2023]
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16
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Jaroenlak P, Boakye DW, Vanichviriyakit R, Williams BAP, Sritunyalucksana K, Itsathitphaisarn O. Identification, characterization and heparin binding capacity of a spore-wall, virulence protein from the shrimp microsporidian, Enterocytozoon hepatopenaei (EHP). Parasit Vectors 2018. [PMID: 29530076 PMCID: PMC5848443 DOI: 10.1186/s13071-018-2758-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Background The microsporidian Enterocytozoon hepatopenaei (EHP) is a spore-forming, intracellular parasite that causes an economically debilitating disease (hepatopancreatic microsporidiosis or HPM) in cultured shrimp. HPM is characterized by growth retardation and wide size variation that can result in economic loss for shrimp farmers. Currently, the infection mechanism of EHP in shrimp is poorly understood, especially at the level of host-parasite interaction. In other microsporidia, spore wall proteins have been reported to be involved in host cell recognition. For the host, heparin, a glycosaminoglycan (GAG) molecule found on cell surfaces, has been shown to be recognized by many parasites such as Plasmodium spp. and Leishmania spp. Results We identified and characterized the first spore wall protein of EHP (EhSWP1). EhSWP1 contains three heparin binding motifs (HBMs) at its N-terminus and a Bin-amphiphysin-Rvs-2 (BAR2) domain at its C-terminus. A phylogenetic analysis revealed that EhSWP1 is similar to an uncharacterized spore wall protein from Enterospora canceri. In a cohabitation bioassay using EHP-infected shrimp with naïve shrimp, the expression of EhSWP1 was detected by RT-PCR in the naïve test shrimp at 20 days after the start of cohabitation. Immunofluorescence analysis confirmed that EhSWP1 was localized in the walls of purified, mature spores. Subcellular localization by an immunoelectron assay revealed that EhSWP1 was distributed in both the endospore and exospore layers. An in vitro binding assay, a competition assay and mutagenesis studies revealed that EhSWP1 is a bona fide heparin binding protein. Conclusions Based on our results, we hypothesize that EhSWP1 is an important host-parasite interaction protein involved in tethering spores to host-cell-surface heparin during the process of infection. Electronic supplementary material The online version of this article (10.1186/s13071-018-2758-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Pattana Jaroenlak
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, Thailand.,Center of Excellence for Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Dominic Wiredu Boakye
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Devon, UK
| | - Rapeepun Vanichviriyakit
- Center of Excellence for Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Faculty of Science, Mahidol University, Bangkok, Thailand.,Department of Anatomy, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Bryony A P Williams
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Devon, UK
| | - Kallaya Sritunyalucksana
- National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), Pathumthani, Thailand.,Shrimp Pathogen Interaction Laboratory (SPI), National Center for Genetic Engineering and Biotechnology (BIOTEC), Bangkok, Thailand
| | - Ornchuma Itsathitphaisarn
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, Thailand. .,Center of Excellence for Shrimp Molecular Biology and Biotechnology (Centex Shrimp), Faculty of Science, Mahidol University, Bangkok, Thailand.
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17
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Abstract
The Slit-Robo GTPase-activating proteins (srGAPs) were first identified as potential Slit-Robo effectors that influence growth cone guidance. Given their N-terminal F-BAR, central GAP and C-terminal SH3 domains, srGAPs have the potential to affect membrane dynamics, Rho family GTPase activity and other binding partners. Recent research has clarified how srGAP family members act in distinct ways at the cell membrane, and has expanded our understanding of the roles of srGAPs in neuronal and non-neuronal cells. Gene duplication of the human-specific paralog of srGAP2 has resulted in srGAP2 family proteins that may have increased the density of dendritic spines and promoted neoteny of the human brain during crucial periods of human evolution, underscoring the importance of srGAPs in the unique sculpting of the human brain. Importantly, srGAPs also play roles outside of the nervous system, including during contact inhibition of cell movement and in establishing and maintaining cell adhesions in epithelia. Changes in srGAP expression may contribute to neurodevelopmental disorders, cancer metastasis and inflammation. As discussed in this Review, much remains to be discovered about how this interesting family of proteins functions in a diverse set of processes in metazoans and the functional roles srGAPs play in human disease.
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Affiliation(s)
- Bethany Lucas
- Program in Genetics, University of Wisconsin-Madison, 1117 W. Johnson St., Madison, WI 53706, USA
| | - Jeff Hardin
- Program in Genetics, University of Wisconsin-Madison, 1117 W. Johnson St., Madison, WI 53706, USA
- Department of Integrative Biology, University of Wisconsin-Madison, 1117 W. Johnson St., Madison, WI 53706, USA
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18
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Sporny M, Guez-Haddad J, Kreusch A, Shakartzi S, Neznansky A, Cross A, Isupov MN, Qualmann B, Kessels MM, Opatowsky Y. Structural History of Human SRGAP2 Proteins. Mol Biol Evol 2017; 34:1463-1478. [PMID: 28333212 PMCID: PMC5435084 DOI: 10.1093/molbev/msx094] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
In the development of the human brain, human-specific genes are considered to play key roles, conferring its unique advantages and vulnerabilities. At the time of Homo lineage divergence from Australopithecus, SRGAP2C gradually emerged through a process of serial duplications and mutagenesis from ancestral SRGAP2A (3.4–2.4 Ma). Remarkably, ectopic expression of SRGAP2C endows cultured mouse brain cells, with human-like characteristics, specifically, increased dendritic spine length and density. To understand the molecular mechanisms underlying this change in neuronal morphology, we determined the structure of SRGAP2A and studied the interplay between SRGAP2A and SRGAP2C. We found that: 1) SRGAP2A homo-dimerizes through a large interface that includes an F-BAR domain, a newly identified F-BAR extension (Fx), and RhoGAP-SH3 domains. 2) SRGAP2A has an unusual inverse geometry, enabling associations with lamellipodia and dendritic spine heads in vivo, and scaffolding of membrane protrusions in cell culture. 3) As a result of the initial partial duplication event (∼3.4 Ma), SRGAP2C carries a defective Fx-domain that severely compromises its solubility and membrane-scaffolding ability. Consistently, SRGAP2A:SRAGP2C hetero-dimers form, but are insoluble, inhibiting SRGAP2A activity. 4) Inactivation of SRGAP2A is sensitive to the level of hetero-dimerization with SRGAP2C. 5) The primal form of SRGAP2C (P-SRGAP2C, existing between ∼3.4 and 2.4 Ma) is less effective in hetero-dimerizing with SRGAP2A than the modern SRGAP2C, which carries several substitutions (from ∼2.4 Ma). Thus, the genetic mutagenesis phase contributed to modulation of SRGAP2A’s inhibition of neuronal expansion, by introducing and improving the formation of inactive SRGAP2A:SRGAP2C hetero-dimers, indicating a stepwise involvement of SRGAP2C in human evolutionary history.
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Affiliation(s)
- Michael Sporny
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Julia Guez-Haddad
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Annett Kreusch
- Institute for Biochemistry I, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
| | - Sivan Shakartzi
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Avi Neznansky
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
| | - Alice Cross
- Department of Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Michail N Isupov
- Department of Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Britta Qualmann
- Institute for Biochemistry I, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
| | - Michael M Kessels
- Institute for Biochemistry I, Jena University Hospital, Friedrich Schiller University Jena, Jena, Germany
| | - Yarden Opatowsky
- The Mina & Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, Israel
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19
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Mahadevan V, Khademullah CS, Dargaei Z, Chevrier J, Uvarov P, Kwan J, Bagshaw RD, Pawson T, Emili A, De Koninck Y, Anggono V, Airaksinen M, Woodin MA. Native KCC2 interactome reveals PACSIN1 as a critical regulator of synaptic inhibition. eLife 2017; 6:e28270. [PMID: 29028184 PMCID: PMC5640428 DOI: 10.7554/elife.28270] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 09/08/2017] [Indexed: 01/01/2023] Open
Abstract
KCC2 is a neuron-specific K+-Cl- cotransporter essential for establishing the Cl- gradient required for hyperpolarizing inhibition in the central nervous system (CNS). KCC2 is highly localized to excitatory synapses where it regulates spine morphogenesis and AMPA receptor confinement. Aberrant KCC2 function contributes to human neurological disorders including epilepsy and neuropathic pain. Using functional proteomics, we identified the KCC2-interactome in the mouse brain to determine KCC2-protein interactions that regulate KCC2 function. Our analysis revealed that KCC2 interacts with diverse proteins, and its most predominant interactors play important roles in postsynaptic receptor recycling. The most abundant KCC2 interactor is a neuronal endocytic regulatory protein termed PACSIN1 (SYNDAPIN1). We verified the PACSIN1-KCC2 interaction biochemically and demonstrated that shRNA knockdown of PACSIN1 in hippocampal neurons increases KCC2 expression and hyperpolarizes the reversal potential for Cl-. Overall, our global native-KCC2 interactome and subsequent characterization revealed PACSIN1 as a novel and potent negative regulator of KCC2.
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Affiliation(s)
- Vivek Mahadevan
- Department of Cell and Systems BiologyUniversity of TorontoTorontoCanada
| | | | - Zahra Dargaei
- Department of Cell and Systems BiologyUniversity of TorontoTorontoCanada
| | - Jonah Chevrier
- Department of Cell and Systems BiologyUniversity of TorontoTorontoCanada
| | - Pavel Uvarov
- Department of Anatomy, Faculty of MedicineUniversity of HelsinkiHelsinkiFinland
| | - Julian Kwan
- Department of Molecular Genetics, Donnelly Centre for Cellular and Biomolecular ResearchUniversity of TorontoTorontoCanada
| | - Richard D Bagshaw
- Lunenfeld-Tanenbaum Research InstituteMount Sinai HospitalTorontoCanada
| | - Tony Pawson
- Lunenfeld-Tanenbaum Research InstituteMount Sinai HospitalTorontoCanada
| | - Andrew Emili
- Department of Molecular Genetics, Donnelly Centre for Cellular and Biomolecular ResearchUniversity of TorontoTorontoCanada
| | - Yves De Koninck
- Institut Universitaire en Santé Mentale de QuébecQuébecCanada
- Department of Psychiatry and NeuroscienceUniversité LavalQuébecCanada
| | - Victor Anggono
- Queensland Brain Institute, Clem Jones Centre for Ageing Dementia ResearchThe University of QueenslandBrisbaneAustralia
| | - Matti Airaksinen
- Department of Anatomy, Faculty of MedicineUniversity of HelsinkiHelsinkiFinland
| | - Melanie A Woodin
- Department of Cell and Systems BiologyUniversity of TorontoTorontoCanada
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20
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Bertling E, Hotulainen P. New waves in dendritic spine actin cytoskeleton: From branches and bundles to rings, from actin binding proteins to post-translational modifications. Mol Cell Neurosci 2017; 84:77-84. [PMID: 28479292 DOI: 10.1016/j.mcn.2017.05.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2016] [Revised: 04/24/2017] [Accepted: 05/03/2017] [Indexed: 12/21/2022] Open
Abstract
Dendritic spines are small actin-rich protrusions from neuronal dendrites that form the postsynaptic part of most excitatory synapses. Changes in the number or strength of synapses are physiological mechanisms behind learning. The growth and maturation of dendritic spines and the activity-induced changes to their morphology are all based on changes to the actin cytoskeleton. In this review, we will discuss the regulation of the actin cytoskeleton in dendritic spine formation and maturation, as well as in synaptic strengthening. Concerning spine formation, we will focus on spine initiation, which has received less attention in the literature. We will also examine the recently revealed regulation of the actin cytoskeleton through post-translational modifications of actin monomers, in addition to the conventional regulation of actin via actin-binding proteins.
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Affiliation(s)
- Enni Bertling
- Minerva Foundation Institute for Medical Research, Helsinki, Finland
| | - Pirta Hotulainen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland.
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21
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Mallik B, Dwivedi MK, Mushtaq Z, Kumari M, Verma PK, Kumar V. Regulation of neuromuscular junction organization by Rab2 and its effector ICA69 in Drosophila. Development 2017; 144:2032-2044. [PMID: 28455372 DOI: 10.1242/dev.145920] [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: 10/20/2016] [Accepted: 04/19/2017] [Indexed: 12/31/2022]
Abstract
The mechanisms underlying synaptic differentiation, which involves neuronal membrane and cytoskeletal remodeling, are not completely understood. We performed a targeted RNAi-mediated screen of Drosophila BAR-domain proteins and identified islet cell autoantigen 69 kDa (ICA69) as one of the key regulators of morphological differentiation of the larval neuromuscular junction (NMJ). We show that Drosophila ICA69 colocalizes with α-Spectrin at the NMJ. The conserved N-BAR domain of ICA69 deforms liposomes in vitro Full-length ICA69 and the ICAC but not the N-BAR domain of ICA69 induce filopodia in cultured cells. Consistent with its cytoskeleton regulatory role, ICA69 mutants show reduced α-Spectrin immunoreactivity at the larval NMJ. Manipulating levels of ICA69 or its interactor PICK1 alters the synaptic level of ionotropic glutamate receptors (iGluRs). Moreover, reducing PICK1 or Rab2 levels phenocopies ICA69 mutation. Interestingly, Rab2 regulates not only synaptic iGluR but also ICA69 levels. Thus, our data suggest that: (1) ICA69 regulates NMJ organization through a pathway that involves PICK1 and Rab2, and (2) Rab2 functions genetically upstream of ICA69 and regulates NMJ organization and targeting/retention of iGluRs by regulating ICA69 levels.
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Affiliation(s)
- Bhagaban Mallik
- Department of Biological Sciences, AB-3, Indian Institute of Science Education and Research, Bhauri, Bhopal, Madhya Pradesh 462066, India
| | - Manish Kumar Dwivedi
- Department of Biological Sciences, AB-3, Indian Institute of Science Education and Research, Bhauri, Bhopal, Madhya Pradesh 462066, India
| | - Zeeshan Mushtaq
- Department of Biological Sciences, AB-3, Indian Institute of Science Education and Research, Bhauri, Bhopal, Madhya Pradesh 462066, India
| | - Manisha Kumari
- National Institute of Plant Genome Research (NIPGR), New Delhi 110067, India
| | - Praveen Kumar Verma
- National Institute of Plant Genome Research (NIPGR), New Delhi 110067, India
| | - Vimlesh Kumar
- Department of Biological Sciences, AB-3, Indian Institute of Science Education and Research, Bhauri, Bhopal, Madhya Pradesh 462066, India
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22
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Sporny M, Guez-Haddad J, Waterman DG, Isupov MN, Opatowsky Y. Molecular symmetry-constrained systematic search approach to structure solution of the coiled-coil SRGAP2 F-BARx domain. ACTA CRYSTALLOGRAPHICA SECTION D-STRUCTURAL BIOLOGY 2016; 72:1241-1253. [PMID: 27917825 DOI: 10.1107/s2059798316016697] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2016] [Accepted: 10/18/2016] [Indexed: 02/05/2023]
Abstract
SRGAP2 (Slit-Robo GTPase-activating protein 2) is a cytoplasmic protein found to be involved in neuronal branching, restriction of neuronal migration and restriction of the length and density of dendritic postsynaptic spines. The extended F-BAR (F-BARx) domain of SRGAP2 generates membrane protrusions when expressed in COS-7 cells, while most F-BARs induce the opposite effect: membrane invaginations. As a first step to understand this discrepancy, the F-BARx domain of SRGAP2 was isolated and crystallized after co-expression with the carboxy domains of the protein. Diffraction data were collected from two significantly non-isomorphous crystals in the same monoclinic C2 space group. A correct molecular-replacment solution was obtained by applying a molecular symmetry-constrained systematic search approach that took advantage of the conserved biological symmetry of the F-BAR domains. It is shown that similar approaches can solve other F-BAR structures that were previously determined by experimental phasing. Diffraction data were reprocessed with a high-resolution cutoff of 2.2 Å, chosen using less strict statistical criteria. This has improved the outcome of multi-crystal averaging and other density-modification procedures.
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Affiliation(s)
- Michael Sporny
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel
| | - Julia Guez-Haddad
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel
| | | | | | - Yarden Opatowsky
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 52900, Israel
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23
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Hotulainen P, Saarikangas J. The initiation of post-synaptic protrusions. Commun Integr Biol 2016; 9:e1125053. [PMID: 27489575 PMCID: PMC4951170 DOI: 10.1080/19420889.2015.1125053] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Revised: 11/20/2015] [Accepted: 11/20/2015] [Indexed: 02/02/2023] Open
Abstract
The post-synaptic spines of neuronal dendrites are highly elaborate membrane protrusions. Their anatomy, stability and density are intimately linked to cognitive performance. The morphological transitions of spines are powered by coordinated polymerization of actin filaments against the plasma membrane, but how the membrane-associated polymerization is spatially and temporally regulated has remained ill defined. Here, we discuss our recent findings showing that dendritic spines can be initiated by direct membrane bending by the I-BAR protein MIM/Mtss1. This lipid phosphatidylinositol (PI(4,5)P2) signaling-activated membrane bending coordinated spatial actin assembly and promoted spine formation. From recent advances, we formulate a general model to discuss how spatially concentrated protein-lipid microdomains formed by multivalent interactions between lipids and actin/membrane regulatory proteins might launch cell protrusions.
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Affiliation(s)
- Pirta Hotulainen
- Neuroscience Center, University of Helsinki, Helsinki, Finland; Minerva Foundation Institute for Medical Research, Helsinki, Finland
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24
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Zhu Y, Jiang X, Wang C, Liu Y, Fan X, Zhang L, Niu L, Teng M, Li X. Structural insights into the methyl donor recognition model of a novel membrane-binding protein UbiG. Sci Rep 2016; 6:23147. [PMID: 26975567 PMCID: PMC4796655 DOI: 10.1038/srep23147] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2015] [Accepted: 02/25/2016] [Indexed: 02/07/2023] Open
Abstract
UbiG is a SAM-dependent O-methyltransferase, catalyzing two O-methyl transfer steps for ubiquinone biosynthesis in Escherichia coli. UbiG possesses a unique sequence insertion between β4 and α10, which is used for membrane lipid interaction. Interestingly, this sequence insertion also covers the methyl donor binding pocket. Thus, the relationship between membrane binding and entrance of the methyl donor of UbiG during the O-methyl transfer process is a question that deserves further exploration. In this study, we reveal that the membrane-binding region of UbiG gates the entrance of methyl donor. When bound with liposome, UbiG displays an enhanced binding ability toward the methyl donor product S-adenosylhomocysteine. We further employ protein engineering strategies to design UbiG mutants by truncating the membrane interacting region or making it more flexible. The ITC results show that the binding affinity of these mutants to SAH increases significantly compared with that of the wild-type UbiG. Moreover, we determine the structure of UbiG∆(165-187) in complex with SAH. Collectively, our results provide a new angle to cognize the relationship between membrane binding and entrance of the methyl donor of UbiG, which is of benefit for better understanding the O-methyl transfer process for ubiquinone biosynthesis.
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Affiliation(s)
- Yuwei Zhu
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui, 230026, People’s Republic of China,Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Science, Hefei, Anhui, 230026, People’s Republic of China
| | - Xuguang Jiang
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui, 230026, People’s Republic of China,Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Science, Hefei, Anhui, 230026, People’s Republic of China
| | - Chongyuan Wang
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui, 230026, People’s Republic of China,Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Science, Hefei, Anhui, 230026, People’s Republic of China
| | - Yang Liu
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui, 230026, People’s Republic of China,Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Science, Hefei, Anhui, 230026, People’s Republic of China
| | - Xiaojiao Fan
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui, 230026, People’s Republic of China,Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Science, Hefei, Anhui, 230026, People’s Republic of China
| | - Linjuan Zhang
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui, 230026, People’s Republic of China,Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Science, Hefei, Anhui, 230026, People’s Republic of China
| | - Liwen Niu
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui, 230026, People’s Republic of China,Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Science, Hefei, Anhui, 230026, People’s Republic of China
| | - Maikun Teng
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui, 230026, People’s Republic of China,Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Science, Hefei, Anhui, 230026, People’s Republic of China,
| | - Xu Li
- Hefei National Laboratory for Physical Sciences at Microscale, Innovation Center for Cell Signaling Network, School of Life Science, University of Science and Technology of China, Hefei, Anhui, 230026, People’s Republic of China,Key Laboratory of Structural Biology, Hefei Science Center of CAS, Chinese Academy of Science, Hefei, Anhui, 230026, People’s Republic of China,
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