1
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Kim N, Li Y, Yu R, Kwon HS, Song A, Jun MH, Jeong JY, Lee JH, Lim HH, Kim MJ, Kim JW, Oh WJ. Repulsive Sema3E-Plexin-D1 signaling coordinates both axonal extension and steering via activating an autoregulatory factor, Mtss1. eLife 2024; 13:e96891. [PMID: 38526535 PMCID: PMC11001299 DOI: 10.7554/elife.96891] [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: 02/07/2024] [Accepted: 03/14/2024] [Indexed: 03/26/2024] Open
Abstract
Axon guidance molecules are critical for neuronal pathfinding because they regulate directionality and growth pace during nervous system development. However, the molecular mechanisms coordinating proper axonal extension and turning are poorly understood. Here, metastasis suppressor 1 (Mtss1), a membrane protrusion protein, ensured axonal extension while sensitizing axons to the Semaphorin 3E (Sema3E)-Plexin-D1 repulsive cue. Sema3E-Plexin-D1 signaling enhanced Mtss1 expression in projecting striatonigral neurons. Mtss1 localized to the neurite axonal side and regulated neurite outgrowth in cultured neurons. Mtss1 also aided Plexin-D1 trafficking to the growth cone, where it signaled a repulsive cue to Sema3E. Mtss1 ablation reduced neurite extension and growth cone collapse in cultured neurons. Mtss1-knockout mice exhibited fewer striatonigral projections and irregular axonal routes, and these defects were recapitulated in Plxnd1- or Sema3e-knockout mice. These findings demonstrate that repulsive axon guidance activates an exquisite autoregulatory program coordinating both axonal extension and steering during neuronal pathfinding.
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Affiliation(s)
- Namsuk Kim
- Neurovascular Unit Research Group, Korea Brain Research InstituteDaeguRepublic of Korea
| | - Yan Li
- Neurovascular Unit Research Group, Korea Brain Research InstituteDaeguRepublic of Korea
| | - Ri Yu
- Neurovascular Unit Research Group, Korea Brain Research InstituteDaeguRepublic of Korea
| | - Hyo-Shin Kwon
- Neurovascular Unit Research Group, Korea Brain Research InstituteDaeguRepublic of Korea
| | - Anji Song
- Neurovascular Unit Research Group, Korea Brain Research InstituteDaeguRepublic of Korea
| | - Mi-Hee Jun
- Neurovascular Unit Research Group, Korea Brain Research InstituteDaeguRepublic of Korea
| | - Jin-Young Jeong
- Neurovascular Unit Research Group, Korea Brain Research InstituteDaeguRepublic of Korea
- Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science and TechnologyDaeguRepublic of Korea
| | - Ji Hyun Lee
- Neurovascular Unit Research Group, Korea Brain Research InstituteDaeguRepublic of Korea
| | - Hyun-Ho Lim
- Neurovascular Unit Research Group, Korea Brain Research InstituteDaeguRepublic of Korea
| | - Mi-Jin Kim
- Department of Life Sciences, Chung-Ang UniversitySeoulRepublic of Korea
| | - Jung-Woong Kim
- Department of Life Sciences, Chung-Ang UniversitySeoulRepublic of Korea
| | - Won-Jong Oh
- Neurovascular Unit Research Group, Korea Brain Research InstituteDaeguRepublic of Korea
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2
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Biton T, Scher N, Carmon S, Elbaz-Alon Y, Schejter ED, Shilo BZ, Avinoam O. Fusion pore dynamics of large secretory vesicles define a distinct mechanism of exocytosis. J Cell Biol 2023; 222:e202302112. [PMID: 37707500 PMCID: PMC10501449 DOI: 10.1083/jcb.202302112] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Revised: 07/06/2023] [Accepted: 08/24/2023] [Indexed: 09/15/2023] Open
Abstract
Exocrine cells utilize large secretory vesicles (LSVs) up to 10 μm in diameter. LSVs fuse with the apical surface, often recruiting actomyosin to extrude their content through dynamic fusion pores. The molecular mechanism regulating pore dynamics remains largely uncharacterized. We observe that the fusion pores of LSVs in the Drosophila larval salivary glands expand, stabilize, and constrict. Arp2/3 is essential for pore expansion and stabilization, while myosin II is essential for pore constriction. We identify several Bin-Amphiphysin-Rvs (BAR) homology domain proteins that regulate fusion pore expansion and stabilization. We show that the I-BAR protein Missing-in-Metastasis (MIM) localizes to the fusion site and is essential for pore expansion and stabilization. The MIM I-BAR domain is essential but not sufficient for localization and function. We conclude that MIM acts in concert with actin, myosin II, and additional BAR-domain proteins to control fusion pore dynamics, mediating a distinct mode of exocytosis, which facilitates actomyosin-dependent content release that maintains apical membrane homeostasis during secretion.
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Affiliation(s)
- Tom Biton
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Nadav Scher
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Shari Carmon
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Yael Elbaz-Alon
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Eyal D. Schejter
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Ben-Zion Shilo
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Ori Avinoam
- Department of Biomolecular Sciences, Weizmann Institute of Science, Rehovot, Israel
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3
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Zheng S, Wang X, Matskova L, Zhou X, Zhang Z, Kashuba E, Ernberg I, Aspenström P. MTSS1 is downregulated in nasopharyngeal carcinoma (NPC) which disrupts adherens junctions leading to enhanced cell migration and invasion. Front Cell Dev Biol 2023; 11:1275668. [PMID: 37920825 PMCID: PMC10618355 DOI: 10.3389/fcell.2023.1275668] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Accepted: 10/03/2023] [Indexed: 11/04/2023] Open
Abstract
Loss of cell-cell adhesions is the indispensable first step for cancer cells to depart from the primary tumor mass to metastasize. Metastasis suppressor 1 (MTSS1) is frequently lost in metastatic tissues, correlating to advanced tumor stages and poor prognosis across a variety of cancers. Here we explore the anti-metastatic mechanisms of MTSS1, which have not been well understood. We found that MTSS1 is downregulated in NPC tissues. Lower levels of MTSS1 expression correlate to worse prognosis. We show that MTSS1 suppresses NPC cell migration and invasion in vitro through cytoskeletal remodeling at cell-cell borders and assembly of E-cadherin/β-catenin/F-actin in adherens junctions. The I-BAR domain of MTSS1 was both necessary and sufficient to restore this formation of E-cadherin/β-catenin/F-actin-mediated cell adherens junctions.
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Affiliation(s)
- Shixing Zheng
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
- ENT Institute and Department of Otorhinolaryngology, Eye & ENT Hospital, Fudan University, Shanghai, China
| | - Xiaoxia Wang
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Liudmila Matskova
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Xiaoying Zhou
- Scientific Research Centre, Life Science Institute, Guangxi Medical University, Nanning, China
| | - Zhe Zhang
- Department of Otolaryngology-Head and Neck Surgery, First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Elena Kashuba
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
- RE Kavetsky Institute of Experimental Pathology, Oncology and Radiobiology of National Academy of Sciences of Ukraine, Kyiv, Ukraine
| | - Ingemar Ernberg
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
| | - Pontus Aspenström
- Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden
- Rudbeck Laboratory, Department of Immunology, Genetics and Pathology, Uppsala University, Uppsala, Sweden
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4
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Ouzounidis VR, Prevo B, Cheerambathur DK. Sculpting the dendritic landscape: Actin, microtubules, and the art of arborization. Curr Opin Cell Biol 2023; 84:102214. [PMID: 37544207 DOI: 10.1016/j.ceb.2023.102214] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 06/20/2023] [Accepted: 07/05/2023] [Indexed: 08/08/2023]
Abstract
Dendrites are intricately designed neuronal compartments that play a vital role in the gathering and processing of sensory or synaptic inputs. Their diverse and elaborate structures are distinct features of neuronal organization and function. Central to the generation of these dendritic arbors is the neuronal cytoskeleton. In this review, we delve into the current progress toward our understanding of how dendrite arbors are generated and maintained, focusing on the role of the actin and microtubule cytoskeleton.
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Affiliation(s)
- Vasileios R Ouzounidis
- Wellcome Centre for Cell Biology & Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Bram Prevo
- Wellcome Centre for Cell Biology & Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh, EH9 3BF, UK
| | - Dhanya K Cheerambathur
- Wellcome Centre for Cell Biology & Institute of Cell Biology, School of Biological Sciences, The University of Edinburgh, Edinburgh, EH9 3BF, UK.
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5
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Minegishi T, Kastian RF, Inagaki N. Mechanical regulation of synapse formation and plasticity. Semin Cell Dev Biol 2023; 140:82-89. [PMID: 35659473 DOI: 10.1016/j.semcdb.2022.05.017] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2022] [Revised: 05/10/2022] [Accepted: 05/17/2022] [Indexed: 01/28/2023]
Abstract
Dendritic spines are small protrusions arising from dendrites and constitute the major compartment of excitatory post-synapses. They change in number, shape, and size throughout life; these changes are thought to be associated with formation and reorganization of neuronal networks underlying learning and memory. As spines in the brain are surrounded by the microenvironment including neighboring cells and the extracellular matrix, their protrusion requires generation of force to push against these structures. In turn, neighboring cells receive force from protruding spines. Recent studies have identified BAR-domain proteins as being involved in membrane deformation to initiate spine formation. In addition, forces for dendritic filopodium extension and activity-induced spine expansion are generated through cooperation between actin polymerization and clutch coupling. On the other hand, force from expanding spines affects neurotransmitter release from presynaptic terminals. Here, we review recent advances in our understanding of the physical aspects of synapse formation and plasticity, mainly focusing on spine dynamics.
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Affiliation(s)
- Takunori Minegishi
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan
| | - Ria Fajarwati Kastian
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan; Research Center for Genetic Engineering, National Research and Innovation Agency Republic of Indonesia, Cibinong, Bogor, Indonesia
| | - Naoyuki Inagaki
- Laboratory of Systems Neurobiology and Medicine, Division of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan.
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6
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Parker SS, Ly KT, Grant AD, Sweetland J, Wang AM, Parker JD, Roman MR, Saboda K, Roe DJ, Padi M, Wolgemuth CW, Langlais P, Mouneimne G. EVL and MIM/MTSS1 regulate actin cytoskeletal remodeling to promote dendritic filopodia in neurons. J Cell Biol 2023; 222:e202106081. [PMID: 36828364 PMCID: PMC9998662 DOI: 10.1083/jcb.202106081] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 11/22/2022] [Accepted: 01/20/2023] [Indexed: 02/25/2023] Open
Abstract
Dendritic spines are the postsynaptic compartment of a neuronal synapse and are critical for synaptic connectivity and plasticity. A developmental precursor to dendritic spines, dendritic filopodia (DF), facilitate synapse formation by sampling the environment for suitable axon partners during neurodevelopment and learning. Despite the significance of the actin cytoskeleton in driving these dynamic protrusions, the actin elongation factors involved are not well characterized. We identified the Ena/VASP protein EVL as uniquely required for the morphogenesis and dynamics of DF. Using a combination of genetic and optogenetic manipulations, we demonstrated that EVL promotes protrusive motility through membrane-direct actin polymerization at DF tips. EVL forms a complex at nascent protrusions and DF tips with MIM/MTSS1, an I-BAR protein important for the initiation of DF. We proposed a model in which EVL cooperates with MIM to coalesce and elongate branched actin filaments, establishing the dynamic lamellipodia-like architecture of DF.
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Affiliation(s)
- Sara S. Parker
- Department of Cellular and Molecular Medicine, College of Medicine, University of Arizona, Tucson, AZ, USA
| | - Kenneth Tran Ly
- Department of Cellular and Molecular Medicine, College of Medicine, University of Arizona, Tucson, AZ, USA
| | - Adam D. Grant
- Cancer Biology Program, University of Arizona Cancer Center, Tucson, AZ, USA
| | - Jillian Sweetland
- Department of Cellular and Molecular Medicine, College of Medicine, University of Arizona, Tucson, AZ, USA
| | - Ashley M. Wang
- Department of Cellular and Molecular Medicine, College of Medicine, University of Arizona, Tucson, AZ, USA
| | - James D. Parker
- Department of Cellular and Molecular Medicine, College of Medicine, University of Arizona, Tucson, AZ, USA
| | - Mackenzie R. Roman
- Division of Endocrinology, Department of Medicine, College of Medicine, University of Arizona, Tucson, AZ, USA
| | - Kathylynn Saboda
- University of Arizona Cancer Center and Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, AZ, USA
| | - Denise J. Roe
- University of Arizona Cancer Center and Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, AZ, USA
| | - Megha Padi
- Cancer Biology Program, University of Arizona Cancer Center, Tucson, AZ, USA
- Department of Molecular and Cellular Biology, College of Science, University of Arizona, Tucson, AZ, USA
| | - Charles W. Wolgemuth
- University of Arizona Cancer Center and Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, AZ, USA
- Department of Molecular and Cellular Biology, College of Science, University of Arizona, Tucson, AZ, USA
- Department of Physics, College of Science, University of Arizona, Tucson, AZ, USA
- Johns Hopkins Physical Sciences-Oncology Center, Johns Hopkins University, Baltimore, MD, USA
| | - Paul Langlais
- Division of Endocrinology, Department of Medicine, College of Medicine, University of Arizona, Tucson, AZ, USA
| | - Ghassan Mouneimne
- Department of Cellular and Molecular Medicine, College of Medicine, University of Arizona, Tucson, AZ, USA
- Cancer Biology Program, University of Arizona Cancer Center, Tucson, AZ, USA
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7
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Senju Y, Mushtaq T, Vihinen H, Manninen A, Saarikangas J, Ven K, Engel U, Varjosalo M, Jokitalo E, Lappalainen P. Actin-rich lamellipodia-like protrusions contribute to the integrity of epithelial cell-cell junctions. J Biol Chem 2023; 299:104571. [PMID: 36871754 PMCID: PMC10173786 DOI: 10.1016/j.jbc.2023.104571] [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: 12/04/2022] [Revised: 01/11/2023] [Accepted: 02/01/2023] [Indexed: 03/06/2023] Open
Abstract
Metastasis-suppressor 1 (MTSS1) is a membrane-interacting scaffolding protein that regulates the integrity of epithelial cell-cell junctions and functions as a tumor suppressor in a wide range of carcinomas. MTSS1 binds phosphoinositide-rich membranes through its I-BAR domain, and is capable of sensing and generating negative membrane curvature in vitro. However, the mechanisms by which MTSS1 localizes to intercellular junctions in epithelial cells, and contributes to their integrity and maintenance have remained elusive. By carrying out electron microscopy and live-cell imaging on cultured Madin-Darby canine kidney (MDCK) cell monolayers, we provide evidence that adherens junctions of epithelial cells harbor lamellipodia-like, dynamic actin-driven membrane folds, which exhibit high negative membrane curvature at their distal edges. BioID proteomics and imaging experiments demonstrated that MTSS1 associates with an Arp2/3 complex activator, the WAVE-2 complex, in dynamic actin-rich protrusions at cell-cell junctions. Inhibition of Arp2/3 or WAVE-2 suppressed actin filament assembly at adherens junctions, decreased the dynamics of junctional membrane protrusions, and led to defects in epithelial integrity. Together, these results support a model in which membrane-associated MTSS1, together with the WAVE-2 and Arp2/3 complexes, promotes the formation of dynamic lamellipodia-like actin protrusions that contribute to the integrity of cell-cell junctions in epithelial monolayers.
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Affiliation(s)
- Yosuke Senju
- Research Institute for Interdisciplinary Science (RIIS), Okayama University, Japan.
| | - Toiba Mushtaq
- Helsinki Institute of Life Science (HiLIFE) - Institute of Biotechnology, University of Helsinki, Finland
| | - Helena Vihinen
- Helsinki Institute of Life Science (HiLIFE) - Institute of Biotechnology, University of Helsinki, Finland
| | - Aki Manninen
- Faculty of Biochemistry and Molecular Medicine, Biocenter Oulu, University of Oulu, Finland
| | - Juha Saarikangas
- Helsinki Institute of Life Science (HiLIFE), University of Helsinki, Finland; Molecular and Integrative Biosciences Research Programme, Faculty of Biological and Environmental Sciences, Neuroscience Center, University of Helsinki, Finland
| | - Katharina Ven
- Helsinki Institute of Life Science (HiLIFE) - Institute of Biotechnology, University of Helsinki, Finland
| | - Ulrike Engel
- Nikon Imaging Center and Centre for Organismal Studies, Heidelberg University, Germany
| | - Markku Varjosalo
- Helsinki Institute of Life Science (HiLIFE) - Institute of Biotechnology, University of Helsinki, Finland
| | - Eija Jokitalo
- Helsinki Institute of Life Science (HiLIFE) - Institute of Biotechnology, University of Helsinki, Finland
| | - Pekka Lappalainen
- Helsinki Institute of Life Science (HiLIFE) - Institute of Biotechnology, University of Helsinki, Finland
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8
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Saltukoglu D, Özdemir B, Holtmannspötter M, Reski R, Piehler J, Kurre R, Reth M. Plasma membrane topography governs the 3D dynamic localization of IgM B cell antigen receptor clusters. EMBO J 2023; 42:e112030. [PMID: 36594262 PMCID: PMC9929642 DOI: 10.15252/embj.2022112030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 12/04/2022] [Accepted: 12/06/2022] [Indexed: 01/04/2023] Open
Abstract
B lymphocytes recognize bacterial or viral antigens via different classes of the B cell antigen receptor (BCR). Protrusive structures termed microvilli cover lymphocyte surfaces, and are thought to perform sensory functions in screening antigen-bearing surfaces. Here, we have used lattice light-sheet microscopy in combination with tailored custom-built 4D image analysis to study the cell-surface topography of B cells of the Ramos Burkitt's Lymphoma line and the spatiotemporal organization of the IgM-BCR. Ramos B-cell surfaces were found to form dynamic networks of elevated ridges bridging individual microvilli. A fraction of membrane-localized IgM-BCR was found in clusters, which were mainly associated with the ridges and the microvilli. The dynamic ridge-network organization and the IgM-BCR cluster mobility were linked, and both were controlled by Arp2/3 complex activity. Our results suggest that dynamic topographical features of the cell surface govern the localization and transport of IgM-BCR clusters to facilitate antigen screening by B cells.
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Affiliation(s)
- Deniz Saltukoglu
- Department of Molecular Immunology, Biology III, Faculty of BiologyUniversity of FreiburgFreiburgGermany
- Signaling Research Centers CIBSS and BIOSSUniversity of FreiburgFreiburgGermany
| | - Bugra Özdemir
- Signaling Research Centers CIBSS and BIOSSUniversity of FreiburgFreiburgGermany
- Plant Biotechnology, Faculty of BiologyUniversity of FreiburgFreiburgGermany
- Present address:
Euro‐BioImaging, European Molecular Biology Laboratory (EMBL)HeidelbergGermany
| | - Michael Holtmannspötter
- Department of Biology/Chemistry and Center for Cellular NanoanalyticsOsnabrück UniversityOsnabrückGermany
| | - Ralf Reski
- Signaling Research Centers CIBSS and BIOSSUniversity of FreiburgFreiburgGermany
- Plant Biotechnology, Faculty of BiologyUniversity of FreiburgFreiburgGermany
| | - Jacob Piehler
- Department of Biology/Chemistry and Center for Cellular NanoanalyticsOsnabrück UniversityOsnabrückGermany
| | - Rainer Kurre
- Department of Biology/Chemistry and Center for Cellular NanoanalyticsOsnabrück UniversityOsnabrückGermany
| | - Michael Reth
- Department of Molecular Immunology, Biology III, Faculty of BiologyUniversity of FreiburgFreiburgGermany
- Signaling Research Centers CIBSS and BIOSSUniversity of FreiburgFreiburgGermany
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9
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Heck N, Santos MD. Dendritic Spines in Learning and Memory: From First Discoveries to Current Insights. ADVANCES IN NEUROBIOLOGY 2023; 34:311-348. [PMID: 37962799 DOI: 10.1007/978-3-031-36159-3_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
The central nervous system is composed of neural ensembles, and their activity patterns are neural correlates of cognitive functions. Those ensembles are networks of neurons connected to each other by synapses. Most neurons integrate synaptic signal through a remarkable subcellular structure called spine. Dendritic spines are protrusions whose diverse shapes make them appear as a specific neuronal compartment, and they have been the focus of studies for more than a century. Soon after their first description by Ramón y Cajal, it has been hypothesized that spine morphological changes could modify neuronal connectivity and sustain cognitive abilities. Later studies demonstrated that changes in spine density and morphology occurred in experience-dependent plasticity during development, and in clinical cases of mental retardation. This gave ground for the assumption that dendritic spines are the particular locus of cerebral plasticity. With the discovery of synaptic long-term potentiation, a research program emerged with the aim to establish whether dendritic spine plasticity could explain learning and memory. The development of live imaging methods revealed on the one hand that dendritic spine remodeling is compatible with learning process and, on the other hand, that their long-term stability is compatible with lifelong memories. Furthermore, the study of the mechanisms of spine growth and maintenance shed new light on the rules of plasticity. In behavioral paradigms of memory, spine formation or elimination and morphological changes were found to correlate with learning. In a last critical step, recent experiments have provided evidence that dendritic spines play a causal role in learning and memory.
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Affiliation(s)
- Nicolas Heck
- Laboratory Neurosciences Paris Seine, Sorbonne Université, Paris, France.
| | - Marc Dos Santos
- Department of Neuroscience, Northwestern University Feinberg School of Medicine, Chicago, IL, USA
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10
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Bonansco C, Cerpa W, Inestrosa NC. How Are Synapses Born? A Functional and Molecular View of the Role of the Wnt Signaling Pathway. Int J Mol Sci 2022; 24:ijms24010708. [PMID: 36614149 PMCID: PMC9821221 DOI: 10.3390/ijms24010708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 12/16/2022] [Accepted: 12/18/2022] [Indexed: 01/03/2023] Open
Abstract
Synaptic transmission is a dynamic process that requires precise regulation. Early in life, we must be able to forge appropriate connections (add and remove) to control our behavior. Neurons must recognize appropriate targets, and external soluble factors that activate specific signaling cascades provide the regulation needed to achieve this goal. Wnt signaling has been implicated in several forms of synaptic plasticity, including functional and structural changes associated with brain development. The analysis of synapses from an electrophysiological perspective allows us to characterize the functional role of cellular signaling pathways involved in brain development. The application of quantal theory to principles of developmental plasticity offers the possibility of dissecting the function of structural changes associated with the birth of new synapses as well as the maturation of immature silent synapses. Here, we focus on electrophysiological and molecular evidence that the Wnt signaling pathway regulates glutamatergic synaptic transmission, specifically N-methyl-d-aspartate receptors (NMDARs), to control the birth of new synapses. We also focus on the role of Wnts in the conversion of silent synapses into functional synapses.
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Affiliation(s)
- Christian Bonansco
- Centro de Neurobiología y Fisiopatología Integrativa (CENFI), Instituto de Fisiología, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso 2360102, Chile
- Correspondence: (C.B.); (N.C.I.)
| | - Waldo Cerpa
- Laboratorio de Función y Patología Neuronal, Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
- Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Universidad de Magallanes, Punta Arenas 6200000, Chile
| | - Nibaldo C. Inestrosa
- Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Universidad de Magallanes, Punta Arenas 6200000, Chile
- Centro de Envejecimiento y Regeneración (CARE UC), Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago 8331150, Chile
- Correspondence: (C.B.); (N.C.I.)
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11
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Wurz AI, Bunner WP, Szatmari EM, Hughes RM. CRY-BARs: Versatile light-gated molecular tools for the remodeling of membrane architectures. J Biol Chem 2022; 298:102388. [PMID: 35987384 PMCID: PMC9530617 DOI: 10.1016/j.jbc.2022.102388] [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: 03/22/2022] [Revised: 08/06/2022] [Accepted: 08/08/2022] [Indexed: 11/26/2022] Open
Abstract
BAR (Bin, Amphiphysin and Rvs) protein domains are responsible for the generation of membrane curvature and represent a critical mechanical component of cellular functions. Thus, BAR domains have great potential as components of membrane-remodeling tools for cell biologists. In this work, we describe the design and implementation of a family of versatile light-gated I-BAR (inverse-BAR) domain containing tools derived from the fusion of the A. thaliana Cryptochrome 2 photoreceptor and I-BAR protein domains ('CRY-BARs') with applications in the remodeling of membrane architectures and the control of cellular dynamics. By taking advantage of the intrinsic membrane binding propensity of the I-BAR domain, CRY-BARs can be used for spatial and temporal control of cellular processes that require induction of membrane protrusions. Using cell lines and primary neuron cultures, we demonstrate here that the CRY-BAR optogenetic tool evokes membrane dynamics changes associated with cellular activity. Moreover, we provide evidence that ezrin, an actin and PIP2 binding protein, acts as a relay between the plasma membrane and the actin cytoskeleton and therefore is an important mediator of switch function. Overall, we propose that CRY-BARs hold promise as a useful addition to the optogenetic toolkit to study membrane remodeling in live cells.
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Affiliation(s)
- Anna I Wurz
- Department of Chemistry, East Carolina University, Greenville, North Carolina, United States
| | - Wyatt Paul Bunner
- Department of Physical Therapy, East Carolina University, Greenville, North Carolina, United States
| | - Erzsebet M Szatmari
- Department of Physical Therapy, East Carolina University, Greenville, North Carolina, United States
| | - Robert M Hughes
- Department of Chemistry, East Carolina University, Greenville, North Carolina, United States.
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12
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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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13
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Tariq K, Luikart BW. Striking a balance: PIP 2 and PIP 3 signaling in neuronal health and disease. EXPLORATION OF NEUROPROTECTIVE THERAPY 2022; 1:86-100. [PMID: 35098253 PMCID: PMC8797975 DOI: 10.37349/ent.2021.00008] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Phosphoinositides are membrane phospholipids involved in a variety of cellular processes like growth, development, metabolism, and transport. This review focuses on the maintenance of cellular homeostasis of phosphatidylinositol 4,5-bisphosphate (PIP2), and phosphatidylinositol 3,4,5-trisphosphate (PIP3). The critical balance of these PIPs is crucial for regulation of neuronal form and function. The activity of PIP2 and PIP3 can be regulated through kinases, phosphatases, phospholipases and cholesterol microdomains. PIP2 and PIP3 carry out their functions either indirectly through their effectors activating integral signaling pathways, or through direct regulation of membrane channels, transporters, and cytoskeletal proteins. Any perturbations to the balance between PIP2 and PIP3 signaling result in neurodevelopmental and neurodegenerative disorders. This review will discuss the upstream modulators and downstream effectors of the PIP2 and PIP3 signaling, in the context of neuronal health and disease.
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Affiliation(s)
- Kamran Tariq
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
| | - Bryan W Luikart
- Department of Molecular and Systems Biology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, USA
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14
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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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15
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Dendrite tapering actuates a self-organizing signaling circuit for stochastic filopodia initiation in neurons. Proc Natl Acad Sci U S A 2021; 118:2106921118. [PMID: 34686599 DOI: 10.1073/pnas.2106921118] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/01/2021] [Indexed: 01/09/2023] Open
Abstract
How signaling units spontaneously arise from a noisy cellular background is not well understood. Here, we show that stochastic membrane deformations can nucleate exploratory dendritic filopodia, dynamic actin-rich structures used by neurons to sample its surroundings for compatible transcellular contacts. A theoretical analysis demonstrates that corecruitment of positive and negative curvature-sensitive proteins to deformed membranes minimizes the free energy of the system, allowing the formation of long-lived curved membrane sections from stochastic membrane fluctuations. Quantitative experiments show that once recruited, curvature-sensitive proteins form a signaling circuit composed of interlinked positive and negative actin-regulatory feedback loops. As the positive but not the negative feedback loop can sense the dendrite diameter, this self-organizing circuit determines filopodia initiation frequency along tapering dendrites. Together, our findings identify a receptor-independent signaling circuit that employs random membrane deformations to simultaneously elicit and limit formation of exploratory filopodia to distal dendritic sites of developing neurons.
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16
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Trujillo-Estrada L, Vanderklish PW, Nguyen MMT, Kuang RR, Nguyen C, Huynh E, da Cunha C, Javonillo DI, Forner S, Martini AC, Sarraf ST, Simmon VF, Baglietto-Vargas D, LaFerla FM. SPG302 Reverses Synaptic and Cognitive Deficits Without Altering Amyloid or Tau Pathology in a Transgenic Model of Alzheimer's Disease. Neurotherapeutics 2021; 18:2468-2483. [PMID: 34738197 PMCID: PMC8804111 DOI: 10.1007/s13311-021-01143-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/11/2021] [Indexed: 12/04/2022] Open
Abstract
Alzheimer's disease (AD) is conceptualized as a synaptic failure disorder in which loss of glutamatergic synapses is a major driver of cognitive decline. Thus, novel therapeutic strategies aimed at regenerating synapses may represent a promising approach to mitigate cognitive deficits in AD patients. At present, no disease-modifying drugs exist for AD, and approved therapies are palliative at best, lacking in the ability to reverse the synaptic failure. Here, we tested the efficacy of a novel synaptogenic small molecule, SPG302 - a 3rd-generation benzothiazole derivative that increases the density of axospinous glutamatergic synapses - in 3xTg-AD mice. Daily dosing of 3xTg-AD mice with SPG302 at 3 and 30 mg/kg (i.p.) for 4 weeks restored hippocampal synaptic density and improved cognitive function in hippocampal-dependent tasks. Mushroom and stubby spine profiles were increased by SPG302, and associated with enhanced expression of key postsynaptic proteins - including postsynaptic density protein 95 (PSD95), drebrin, and amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) - and increased colocalization of PSD95 with synaptophysin. Notably, SPG302 proved efficacious in this model without modifying Aβ and tau pathology. Thus, our study provides preclinical support for the idea that compounds capable of restoring synaptic density offer a viable strategy to reverse cognitive decline in AD.
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Affiliation(s)
- Laura Trujillo-Estrada
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, 92697, USA
- Departamento Biología Celular, Genetica y Fisiologia, Instituto de Investigacion Biomedica de Malaga-IBIMA, Facultad de Ciencias, Universidad de Malaga, Malaga, Spain
- Centro de Investigacion Biomedica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain
| | - Peter W Vanderklish
- Spinogenix Inc, 10210 Campus Point Drive, Suite 150, San Diego, CA, 92121, USA.
| | - Marie Minh Thu Nguyen
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, 92697, USA
| | - Run Rong Kuang
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, 92697, USA
| | - Caroline Nguyen
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, 92697, USA
| | - Eric Huynh
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, 92697, USA
| | - Celia da Cunha
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, 92697, USA
| | - Dominic Ibarra Javonillo
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, 92697, USA
| | - Stefania Forner
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, 92697, USA
| | - Alessandra C Martini
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, 92697, USA
| | - Stella T Sarraf
- Spinogenix Inc, 10210 Campus Point Drive, Suite 150, San Diego, CA, 92121, USA
| | - Vincent F Simmon
- Spinogenix Inc, 10210 Campus Point Drive, Suite 150, San Diego, CA, 92121, USA.
| | - David Baglietto-Vargas
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, 92697, USA.
- Department of Neurobiology and Behavior, University of California, Irvine, CA, 92697-1450, USA.
- Departamento Biología Celular, Genetica y Fisiologia, Instituto de Investigacion Biomedica de Malaga-IBIMA, Facultad de Ciencias, Universidad de Malaga, Malaga, Spain.
- Centro de Investigacion Biomedica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Madrid, Spain.
| | - Frank M LaFerla
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, 92697, USA.
- Department of Neurobiology and Behavior, University of California, Irvine, CA, 92697-1450, USA.
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17
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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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18
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Nishimura T, Oyama T, Hu HT, Fujioka T, Hanawa-Suetsugu K, Ikeda K, Yamada S, Kawana H, Saigusa D, Ikeda H, Kurata R, Oono-Yakura K, Kitamata M, Kida K, Hikita T, Mizutani K, Yasuhara K, Mimori-Kiyosue Y, Oneyama C, Kurimoto K, Hosokawa Y, Aoki J, Takai Y, Arita M, Suetsugu S. Filopodium-derived vesicles produced by MIM enhance the migration of recipient cells. Dev Cell 2021; 56:842-859.e8. [PMID: 33756122 DOI: 10.1016/j.devcel.2021.02.029] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 12/31/2020] [Accepted: 02/23/2021] [Indexed: 12/19/2022]
Abstract
Extracellular vesicles (EVs) are classified as large EVs (l-EVs, or microvesicles) and small EVs (s-EVs, or exosomes). S-EVs are thought to be generated from endosomes through a process that mainly depends on the ESCRT protein complex, including ALG-2 interacting protein X (ALIX). However, the mechanisms of l-EV generation from the plasma membrane have not been identified. Membrane curvatures are generated by the bin-amphiphysin-rvs (BAR) family proteins, among which the inverse BAR (I-BAR) proteins are involved in filopodial protrusions. Here, we show that the I-BAR proteins, including missing in metastasis (MIM), generate l-EVs by scission of filopodia. Interestingly, MIM-containing l-EV production was promoted by in vivo equivalent external forces and by the suppression of ALIX, suggesting an alternative mechanism of vesicle formation to s-EVs. The MIM-dependent l-EVs contained lysophospholipids and proteins, including IRS4 and Rac1, which stimulated the migration of recipient cells through lamellipodia formation. Thus, these filopodia-dependent l-EVs, which we named as filopodia-derived vesicles (FDVs), modify cellular behavior.
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Affiliation(s)
- Tamako Nishimura
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
| | - Takuya Oyama
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
| | - Hooi Ting Hu
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
| | - Toshifumi Fujioka
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
| | - Kyoko Hanawa-Suetsugu
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
| | - Kazutaka Ikeda
- Laboratory for Metabolomics, RIKEN Center for Integrative Medical Sciences, Yokohama 230-0045, Japan; Cellular and Molecular Epigenetics Laboratory, Graduate School of Medical Life Science, Yokohama City University, Yokohama 230-0045, Japan; Kazusa DNA Research Institute, 2-6-7 Kazusa, kamatari, Kisarazu, Chiba 292-0818, Japan
| | - Sohei Yamada
- Division of Materials Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
| | - Hiroki Kawana
- Laboratory of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - Daisuke Saigusa
- Tohoku University Tohoku Medical Megabank Organization, 2-1, Seiryo-machi, Aoba-ku, Sendai 980-8573, Japan
| | - Hiroki Ikeda
- Department of Embryology, Nara Medical University, Kashihara 634-0813, Nara, Japan
| | - Rie Kurata
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
| | - Kayoko Oono-Yakura
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
| | - Manabu Kitamata
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
| | - Kazuki Kida
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
| | - Tomoya Hikita
- Division of Cancer Cell Regulation, Aichi Cancer Center Research Institute, 1-1 Kanokoden, Chikusa-ku, Nagoya 464-8681, Japan
| | - Kiyohito Mizutani
- Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe 650-0047, Japan
| | - Kazuma Yasuhara
- Division of Materials Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
| | - Yuko Mimori-Kiyosue
- Laboratory for Molecular and Cellular Dynamics, RIKEN Center for Biosystems Dynamics Research, Minatojima-minaminachi, Chuo-ku, Kobe, Hyogo 650-0047, Japan
| | - Chitose Oneyama
- Division of Cancer Cell Regulation, Aichi Cancer Center Research Institute, 1-1 Kanokoden, Chikusa-ku, Nagoya 464-8681, Japan
| | - Kazuki Kurimoto
- Department of Embryology, Nara Medical University, Kashihara 634-0813, Nara, Japan
| | - Yoichiroh Hosokawa
- Division of Materials Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan
| | - Junken Aoki
- Laboratory of Health Chemistry, Graduate School of Pharmaceutical Sciences, The University of Tokyo, Bunkyo, Tokyo 113-0033, Japan
| | - Yoshimi Takai
- Department of Biochemistry and Molecular Biology, Kobe University Graduate School of Medicine, Kobe 650-0047, Japan
| | - Makoto Arita
- Laboratory for Metabolomics, RIKEN Center for Integrative Medical Sciences, Yokohama 230-0045, Japan; Cellular and Molecular Epigenetics Laboratory, Graduate School of Medical Life Science, Yokohama City University, Yokohama 230-0045, Japan; Division of Physiological Chemistry and Metabolism, Graduate School of Pharmaceutical Sciences, Keio University, Tokyo 105-0011, Japan
| | - Shiro Suetsugu
- Division of Biological Science, Nara Institute of Science and Technology, Ikoma 630-0192, Japan; Data Science Center, Nara Institute of Science and Technology, Ikoma 630-0192, Japan.
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Recent developments in membrane curvature sensing and induction by proteins. Biochim Biophys Acta Gen Subj 2021; 1865:129971. [PMID: 34333084 DOI: 10.1016/j.bbagen.2021.129971] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 07/11/2021] [Accepted: 07/25/2021] [Indexed: 12/22/2022]
Abstract
BACKGROUND Membrane-bound intracellular organelles have characteristic shapes attributed to different local membrane curvatures, and these attributes are conserved across species. Over the past decade, it has been confirmed that specific proteins control the large curvatures of the membrane, whereas many others due to their specific structural features can sense the curvatures and bind to the specific geometrical cues. Elucidating the interplay between sensing and induction is indispensable to understand the mechanisms behind various biological processes such as vesicular trafficking and budding. SCOPE OF REVIEW We provide an overview of major classes of membrane proteins and the mechanisms of curvature sensing and induction. We then discuss the importance of membrane elastic characteristics to induce the membrane shapes similar to intracellular organelles. Finally, we survey recently available assays developed for studying the curvature sensing and induction by many proteins. MAJOR CONCLUSIONS Recent theoretical/computational modeling along with experimental studies have uncovered fascinating connections between lipid membrane and protein interactions. However, the phenomena of protein localization and synchronization to generate spatiotemporal dynamics in membrane morphology are yet to be fully understood. GENERAL SIGNIFICANCE The understanding of protein-membrane interactions is essential to shed light on various biological processes. This further enables the technological applications of many natural proteins/peptides in therapeutic treatments. The studies of membrane dynamic shapes help to understand the fundamental functions of membranes, while the medicinal roles of various macromolecules (such as proteins, peptides, etc.) are being increasingly investigated.
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20
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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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21
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Carlton AJ, Halford J, Underhill A, Jeng J, Avenarius MR, Gilbert ML, Ceriani F, Ebisine K, Brown SDM, Bowl MR, Barr‐Gillespie PG, Marcotti W. Loss of Baiap2l2 destabilizes the transducing stereocilia of cochlear hair cells and leads to deafness. J Physiol 2021; 599:1173-1198. [PMID: 33151556 PMCID: PMC7898316 DOI: 10.1113/jp280670] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2020] [Accepted: 10/27/2020] [Indexed: 12/17/2022] Open
Abstract
KEY POINTS Mechanoelectrical transduction at auditory hair cells requires highly specialized stereociliary bundles that project from their apical surface, forming a characteristic graded 'staircase' structure. The morphogenesis and maintenance of these stereociliary bundles is a tightly regulated process requiring the involvement of several actin-binding proteins, many of which are still unidentified. We identify a new stereociliary protein, the I-BAR protein BAIAP2L2, which localizes to the tips of the shorter transducing stereocilia in both inner and outer hair cells (IHCs and OHCs). We find that Baiap2l2 deficient mice lose their second and third rows of stereocilia, their mechanoelectrical transducer current, and develop progressive hearing loss, becoming deaf by 8 months of age. We demonstrate that BAIAP2L2 localization to stereocilia tips is dependent on the motor protein MYO15A and its cargo EPS8. We propose that BAIAP2L2 is a new key protein required for the maintenance of the transducing stereocilia in mature cochlear hair cells. ABSTRACT The transduction of sound waves into electrical signals depends upon mechanosensitive stereociliary bundles that project from the apical surface of hair cells within the cochlea. The height and width of these actin-based stereocilia is tightly regulated throughout life to establish and maintain their characteristic staircase-like structure, which is essential for normal mechanoelectrical transduction. Here, we show that BAIAP2L2, a member of the I-BAR protein family, is a newly identified hair bundle protein that is localized to the tips of the shorter rows of transducing stereocilia in mouse cochlear hair cells. BAIAP2L2 was detected by immunohistochemistry from postnatal day 2.5 (P2.5) throughout adulthood. In Baiap2l2 deficient mice, outer hair cells (OHCs), but not inner hair cells (IHCs), began to lose their third row of stereocilia and showed a reduction in the size of the mechanoelectrical transducer current from just after P9. Over the following post-hearing weeks, the ordered staircase structure of the bundle progressively deteriorates, such that, by 8 months of age, both OHCs and IHCs of Baiap2l2 deficient mice have lost most of the second and third rows of stereocilia and become deaf. We also found that BAIAP2L2 interacts with other key stereociliary proteins involved in normal hair bundle morphogenesis, such as CDC42, RAC1, EPS8 and ESPNL. Furthermore, we show that BAIAP2L2 localization to the stereocilia tips depends on the motor protein MYO15A and its cargo EPS8. We propose that BAIAP2L2 is key to maintenance of the normal actin structure of the transducing stereocilia in mature mouse cochlear hair cells.
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Affiliation(s)
- Adam J. Carlton
- Department of Biomedical ScienceUniversity of SheffieldSheffieldUK
- Neuroscience InstituteUniversity of SheffieldSheffieldUK
| | - Julia Halford
- Oregon Hearing Research Center & Vollum InstituteOregon Health & Science UniversityPortlandORUSA
| | - Anna Underhill
- Department of Biomedical ScienceUniversity of SheffieldSheffieldUK
- Neuroscience InstituteUniversity of SheffieldSheffieldUK
| | - Jing‐Yi Jeng
- Department of Biomedical ScienceUniversity of SheffieldSheffieldUK
- Neuroscience InstituteUniversity of SheffieldSheffieldUK
| | - Matthew R. Avenarius
- Oregon Hearing Research Center & Vollum InstituteOregon Health & Science UniversityPortlandORUSA
- Present address: Department of Pathology Wexner Medical CenterThe Ohio State UniversityColumbusOHUSA
| | - Merle L. Gilbert
- Oregon Hearing Research Center & Vollum InstituteOregon Health & Science UniversityPortlandORUSA
- Present address: US Army Medical Department Activity‐KoreaCamp HumphreysRepublic of Korea
| | - Federico Ceriani
- Department of Biomedical ScienceUniversity of SheffieldSheffieldUK
- Neuroscience InstituteUniversity of SheffieldSheffieldUK
| | | | - Steve D. M. Brown
- Mammalian Genetics UnitMRC Harwell InstituteHarwell CampusOxfordshireUK
| | - Michael R. Bowl
- Mammalian Genetics UnitMRC Harwell InstituteHarwell CampusOxfordshireUK
- Present address: UCL Ear InstituteUniversity College LondonLondonUK
| | - Peter G. Barr‐Gillespie
- Oregon Hearing Research Center & Vollum InstituteOregon Health & Science UniversityPortlandORUSA
- Oregon Hearing Research CenterOregon Health & Science UniversityPortlandORUSA
| | - Walter Marcotti
- Department of Biomedical ScienceUniversity of SheffieldSheffieldUK
- Neuroscience InstituteUniversity of SheffieldSheffieldUK
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22
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Ljubojevic N, Henderson JM, Zurzolo C. The Ways of Actin: Why Tunneling Nanotubes Are Unique Cell Protrusions. Trends Cell Biol 2020; 31:130-142. [PMID: 33309107 DOI: 10.1016/j.tcb.2020.11.008] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 11/09/2020] [Accepted: 11/16/2020] [Indexed: 12/22/2022]
Abstract
Actin remodeling is at the heart of the response of cells to external or internal stimuli, allowing a variety of membrane protrusions to form. Fifteen years ago, tunneling nanotubes (TNTs) were identified, bringing a novel addition to the family of actin-supported cellular protrusions. Their unique property as conduits for cargo transfer between distant cells emphasizes the unique nature of TNTs among other protrusions. While TNTs in different pathological and physiological scenarios have been described, the molecular basis of how TNTs form is not well understood. In this review, we discuss the role of several actin regulators in the formation of TNTs and suggest potential players based on their comparison with other actin-based protrusions. New perspectives for discovering a distinct TNT formation pathway would enable us to target them in treating the increasing number of TNT-involved pathologies.
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Affiliation(s)
- Nina Ljubojevic
- Membrane Traffic and Pathogenesis, Institut Pasteur, UMR3691 CNRS, 75015 Paris, France; Sorbonne Université, ED394 - Physiologie, Physiopathologie et Thérapeutique, 75005 Paris, France
| | - J Michael Henderson
- Membrane Traffic and Pathogenesis, Institut Pasteur, UMR3691 CNRS, 75015 Paris, France; Laboratoire Physico-Chimie Curie, Institut Curie, PSL Research University, CNRS UMR168, 75005 Paris, France
| | - Chiara Zurzolo
- Membrane Traffic and Pathogenesis, Institut Pasteur, UMR3691 CNRS, 75015 Paris, France.
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23
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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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24
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Brosig A, Fuchs J, Ipek F, Kroon C, Schrötter S, Vadhvani M, Polyzou A, Ledderose J, van Diepen M, Holzhütter HG, Trimbuch T, Gimber N, Schmoranzer J, Lieberam I, Rosenmund C, Spahn C, Scheerer P, Szczepek M, Leondaritis G, Eickholt BJ. The Axonal Membrane Protein PRG2 Inhibits PTEN and Directs Growth to Branches. Cell Rep 2020; 29:2028-2040.e8. [PMID: 31722215 PMCID: PMC6856728 DOI: 10.1016/j.celrep.2019.10.039] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2018] [Revised: 08/09/2019] [Accepted: 10/09/2019] [Indexed: 01/03/2023] Open
Abstract
In developing neurons, phosphoinositide 3-kinases (PI3Ks) control axon growth and branching by positively regulating PI3K/PI(3,4,5)P3, but how neurons are able to generate sufficient PI(3,4,5)P3 in the presence of high levels of the antagonizing phosphatase PTEN is difficult to reconcile. We find that normal axon morphogenesis involves homeostasis of elongation and branch growth controlled by accumulation of PI(3,4,5)P3 through PTEN inhibition. We identify a plasma membrane-localized protein-protein interaction of PTEN with plasticity-related gene 2 (PRG2). PRG2 stabilizes membrane PI(3,4,5)P3 by inhibiting PTEN and localizes in nanoclusters along axon membranes when neurons initiate their complex branching behavior. We demonstrate that PRG2 is both sufficient and necessary to account for the ability of neurons to generate axon filopodia and branches in dependence on PI3K/PI(3,4,5)P3 and PTEN. Our data indicate that PRG2 is part of a neuronal growth program that induces collateral branch growth in axons by conferring local inhibition of PTEN. Neuronal axon growth and branching is globally regulated by PI3K/PTEN signaling PRG2 inhibits PTEN and stabilizes PIP3 and F-actin PRG2 localizes to nanoclusters on the axonal membrane and coincides with branching PRG2 promotes axonal filopodia and branching dependent on PI3K/PTEN
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Affiliation(s)
- Annika Brosig
- Institute of Biochemistry, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Joachim Fuchs
- Institute of Biochemistry, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Fatih Ipek
- Institute of Biochemistry, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany; Group Protein X-ray Crystallography and Signal Transduction, Institute of Medical Physics and Biophysics, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Cristina Kroon
- Institute of Biochemistry, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Sandra Schrötter
- Institute of Biochemistry, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany; Department of Genetics and Complex Diseases, T.H. Chan Harvard School of Public Health, Boston, MA 02120, USA
| | - Mayur Vadhvani
- Institute of Biochemistry, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Alexandra Polyzou
- Department of Pharmacology, Faculty of Medicine, School of Health Sciences, University of Ioannina, 45110 Ioannina, Greece
| | - Julia Ledderose
- Institute of Biochemistry, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Michiel van Diepen
- Institute of Infectious Disease and Molecular Medicine, Faculty of Health Science, University of Cape Town, Cape Town, South Africa
| | - Hermann-Georg Holzhütter
- Institute of Biochemistry, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Thorsten Trimbuch
- Institute of Neurophysiology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Niclas Gimber
- Advanced Medical Bioimaging Core Facility (AMBIO), Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Jan Schmoranzer
- Advanced Medical Bioimaging Core Facility (AMBIO), Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Ivo Lieberam
- Centre for Stem Cells and Regenerative Medicine and Centre for Developmental Neurobiology, MRC Centre for Neurodevelopmental Disorders, King's College, London, UK
| | - Christian Rosenmund
- NeuroCure-Cluster of Excellence, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany; Institute of Neurophysiology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Christian Spahn
- NeuroCure-Cluster of Excellence, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany; Institute of Medical Physics and Biophysics, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Patrick Scheerer
- Group Protein X-ray Crystallography and Signal Transduction, Institute of Medical Physics and Biophysics, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - Michal Szczepek
- Group Protein X-ray Crystallography and Signal Transduction, Institute of Medical Physics and Biophysics, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany
| | - George Leondaritis
- Department of Pharmacology, Faculty of Medicine, School of Health Sciences, University of Ioannina, 45110 Ioannina, Greece.
| | - Britta J Eickholt
- Institute of Biochemistry, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany; NeuroCure-Cluster of Excellence, Charité-Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.
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25
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Albanesi JP, Barylko B, DeMartino GN, Jameson DM. Palmitoylated Proteins in Dendritic Spine Remodeling. Front Synaptic Neurosci 2020; 12:22. [PMID: 32655390 PMCID: PMC7325885 DOI: 10.3389/fnsyn.2020.00022] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Accepted: 05/12/2020] [Indexed: 12/14/2022] Open
Abstract
Activity-responsive changes in the actin cytoskeleton are required for the biogenesis, motility, and remodeling of dendritic spines. These changes are governed by proteins that regulate the polymerization, depolymerization, bundling, and branching of actin filaments. Thus, processes that have been extensively characterized in the context of non-neuronal cell shape change and migration are also critical for learning and memory. In this review article, we highlight actin regulatory proteins that associate, at least transiently, with the dendritic plasma membrane. All of these proteins have been shown, either in directed studies or in high-throughput screens, to undergo palmitoylation, a potentially reversible, and stimulus-dependent cysteine modification. Palmitoylation increases the affinity of peripheral proteins for the membrane bilayer and contributes to their subcellular localization and recruitment to cholesterol-rich membrane microdomains.
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Affiliation(s)
- Joseph P. Albanesi
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Barbara Barylko
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - George N. DeMartino
- Department of Physiology, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - David M. Jameson
- Department of Cell and Molecular Biology, University of Hawaii, Honolulu, HI, United States
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26
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Sarapulov AV, Petrov P, Hernández-Pérez S, Šuštar V, Kuokkanen E, Cords L, Samuel RVM, Vainio M, Fritzsche M, Carrasco YR, Mattila PK. Missing-in-Metastasis/Metastasis Suppressor 1 Regulates B Cell Receptor Signaling, B Cell Metabolic Potential, and T Cell-Independent Immune Responses. Front Immunol 2020; 11:599. [PMID: 32373113 PMCID: PMC7176992 DOI: 10.3389/fimmu.2020.00599] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 03/16/2020] [Indexed: 11/13/2022] Open
Abstract
Efficient generation of antibodies by B cells is one of the prerequisites of protective immunity. B cell activation by cognate antigens via B cell receptors (BCRs), or pathogen-associated molecules through pattern-recognition receptors, such as Toll-like receptors (TLRs), leads to transcriptional and metabolic changes that ultimately transform B cells into antibody-producing plasma cells or memory cells. BCR signaling and a number of steps downstream of it rely on coordinated action of cellular membranes and the actin cytoskeleton, tightly controlled by concerted action of multiple regulatory proteins, some of them exclusive to B cells. Here, we dissect the role of Missing-In-Metastasis (MIM), or Metastasis suppressor 1 (MTSS1), a cancer-associated membrane and actin cytoskeleton regulating protein, in B cell-mediated immunity by taking advantage of MIM knockout mouse strain. We show undisturbed B cell development and largely normal composition of B cell compartments in the periphery. Interestingly, we found that MIM-/- B cells are defected in BCR signaling in response to surface-bound antigens but, on the other hand, show increased metabolic activity after stimulation with LPS or CpG. In vivo, MIM knockout animals exhibit impaired IgM antibody responses to immunization with T cell-independent antigen. This study provides the first comprehensive characterization of MIM in B cells, demonstrates its regulatory role for B cell-mediated immunity, as well as proposes new functions for MIM in tuning receptor signaling and cellular metabolism, processes, which may also contribute to the poorly understood functions of MIM in cancer.
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Affiliation(s)
- Alexey V. Sarapulov
- Institute of Biomedicine and MediCity Research Laboratories, University of Turku, Turku, Finland
- Turku Bioscience, University of Turku and Åbo Akademi University, Turku, Finland
| | - Petar Petrov
- Institute of Biomedicine and MediCity Research Laboratories, University of Turku, Turku, Finland
- Turku Bioscience, University of Turku and Åbo Akademi University, Turku, Finland
| | - Sara Hernández-Pérez
- Institute of Biomedicine and MediCity Research Laboratories, University of Turku, Turku, Finland
- Turku Bioscience, University of Turku and Åbo Akademi University, Turku, Finland
| | - Vid Šuštar
- Institute of Biomedicine and MediCity Research Laboratories, University of Turku, Turku, Finland
| | - Elina Kuokkanen
- Institute of Biomedicine and MediCity Research Laboratories, University of Turku, Turku, Finland
| | - Lena Cords
- MRC Human Immunology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Rufus V. M. Samuel
- Institute of Biomedicine and MediCity Research Laboratories, University of Turku, Turku, Finland
| | - Marika Vainio
- Institute of Biomedicine and MediCity Research Laboratories, University of Turku, Turku, Finland
- Turku Bioscience, University of Turku and Åbo Akademi University, Turku, Finland
| | - Marco Fritzsche
- Kennedy Institute for Rheumatology, University of Oxford, Oxford, United Kingdom
- Rosalind Franklin Institute, Didcot, United Kingdom
| | - Yolanda R. Carrasco
- Department of Immunology and Oncology, Centro Nacional de Biotecnología (CNB)-CSIC, Madrid, Spain
| | - Pieta K. Mattila
- Institute of Biomedicine and MediCity Research Laboratories, University of Turku, Turku, Finland
- Turku Bioscience, University of Turku and Åbo Akademi University, Turku, Finland
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27
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Harvey PD, Sun N, Bigdeli TB, Fanous AH, Aslan M, Malhotra AK, Lu Q, Hu Y, Li B, Chen Q, Mane S, Miller P, Rajeevan N, Sayward F, Cheung KH, Li Y, Greenwood TA, Gur RE, Braff DL, Brophy M, Pyarajan S, O'Leary TJ, Gleason T, Przygodszki R, Muralidhar S, Gaziano JM, Concato J, Zhao H, Siever LJ. Genome-wide association study of cognitive performance in U.S. veterans with schizophrenia or bipolar disorder. Am J Med Genet B Neuropsychiatr Genet 2020; 183:181-194. [PMID: 31872970 DOI: 10.1002/ajmg.b.32775] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 11/22/2019] [Accepted: 12/09/2019] [Indexed: 12/25/2022]
Abstract
Cognitive impairment is a frequent and serious problem in patients with various forms of severe mental illnesses (SMI), including schizophrenia (SZ) and bipolar disorder (BP). Recent research suggests genetic links to several cognitive phenotypes in both SMI and in the general population. Our goal in this study was to identify potential genomic signatures of cognitive functioning in veterans with severe mental illness and compare them to previous findings for cognition across different populations. Veterans Affairs (VA) Cooperative Studies Program (CSP) Study #572 evaluated cognitive and functional capacity measures among SZ and BP patients. In conjunction with the VA Million Veteran Program, 3,959 European American (1,095 SZ, 2,864 BP) and 2,601 African American (1,095 SZ, 2,864 BP) patients were genotyped using a custom Affymetrix Axiom Biobank array. We performed a genome-wide association study of global cognitive functioning, constructed polygenic scores for SZ and cognition in the general population, and examined genetic correlations with 2,626 UK Biobank traits. Although no single locus attained genome-wide significance, observed allelic effects were strongly consistent with previous studies. We observed robust associations between global cognitive functioning and polygenic scores for cognitive performance, intelligence, and SZ risk. We also identified significant genetic correlations with several cognition-related traits in UK Biobank. In a diverse cohort of U.S. veterans with SZ or BP, we demonstrate broad overlap of common genetic effects on cognition in the general population, and find that greater polygenic loading for SZ risk is associated with poorer cognitive performance.
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Affiliation(s)
- Philip D Harvey
- Research Service, Bruce W. Carter Miami Veterans Affairs (VA) Medical Center, Miami, Florida.,Department of Psychiatry and Behavioral Sciences, University of Miami School of Medicine, Miami, Florida
| | - Ning Sun
- Clinical Epidemiology Research Center (CERC), VA Connecticut Healthcare System, West Haven, Connecticut.,Yale University School of Medicine, New Haven, Connecticut
| | - Tim B Bigdeli
- Department of Psychiatry, VA New York Harbor Healthcare System, Brooklyn, New York.,Department of Psychiatry and Behavioral Sciences, SUNY Downstate Medical Center, Brooklyn, New York
| | - Ayman H Fanous
- Department of Psychiatry, VA New York Harbor Healthcare System, Brooklyn, New York.,Department of Psychiatry and Behavioral Sciences, SUNY Downstate Medical Center, Brooklyn, New York
| | - Mihaela Aslan
- Clinical Epidemiology Research Center (CERC), VA Connecticut Healthcare System, West Haven, Connecticut.,Yale University School of Medicine, New Haven, Connecticut
| | - Anil K Malhotra
- Center for Psychiatric Neuroscience, Feinstein Institute for Medical Research, Manhasset, New York.,Division of Psychiatry Research, The Zucker Hillside Hospital, Northwell Health, Glen Oaks, New York.,Department of Psychiatry, Hofstra Northwell School of Medicine, Hempstead, New York
| | - Qiongshi Lu
- Yale University School of Medicine, New Haven, Connecticut.,Department of Biostatistics & Medical Informatics, University of Wisconsin-Madison, Madison, Wisconsin
| | - Yiming Hu
- Yale University School of Medicine, New Haven, Connecticut
| | - Boyang Li
- Yale University School of Medicine, New Haven, Connecticut
| | - Quan Chen
- Clinical Epidemiology Research Center (CERC), VA Connecticut Healthcare System, West Haven, Connecticut.,Yale University School of Medicine, New Haven, Connecticut
| | - Shrikant Mane
- Yale University School of Medicine, New Haven, Connecticut
| | - Perry Miller
- Clinical Epidemiology Research Center (CERC), VA Connecticut Healthcare System, West Haven, Connecticut.,Yale University School of Medicine, New Haven, Connecticut
| | - Nallakkandi Rajeevan
- Clinical Epidemiology Research Center (CERC), VA Connecticut Healthcare System, West Haven, Connecticut.,Yale University School of Medicine, New Haven, Connecticut
| | - Frederick Sayward
- Clinical Epidemiology Research Center (CERC), VA Connecticut Healthcare System, West Haven, Connecticut.,Yale University School of Medicine, New Haven, Connecticut
| | - Kei-Hoi Cheung
- Clinical Epidemiology Research Center (CERC), VA Connecticut Healthcare System, West Haven, Connecticut.,Yale University School of Medicine, New Haven, Connecticut
| | - Yuli Li
- Clinical Epidemiology Research Center (CERC), VA Connecticut Healthcare System, West Haven, Connecticut.,Yale University School of Medicine, New Haven, Connecticut
| | | | - Raquel E Gur
- Department of Psychiatry, University of Pennsylvania Perelman School of Medicine and Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.,Department of Child & Adolescent Psychiatry and Lifespan Brain Institute, University of Pennsylvania Perelman School of Medicine and Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | - David L Braff
- Department of Psychiatry, University of California, San Diego, California.,VISN-22 Mental Illness, Research, Education and Clinical Center (MIRECC), VA San Diego Healthcare System, San Diego, California
| | | | - Mary Brophy
- Massachusetts Area Veterans Epidemiology Research, and Information Center (MAVERIC), Jamaica Plain, Massachusetts.,Boston University School of Medicine, Boston, Massachusetts
| | - Saiju Pyarajan
- Massachusetts Area Veterans Epidemiology Research, and Information Center (MAVERIC), Jamaica Plain, Massachusetts
| | - Timothy J O'Leary
- Office of Research and Development, Veterans Health Administration, Washington, District of Columbia
| | - Theresa Gleason
- Office of Research and Development, Veterans Health Administration, Washington, District of Columbia
| | - Ronald Przygodszki
- Office of Research and Development, Veterans Health Administration, Washington, District of Columbia
| | - Sumitra Muralidhar
- Office of Research and Development, Veterans Health Administration, Washington, District of Columbia
| | - J Michael Gaziano
- Massachusetts Area Veterans Epidemiology Research, and Information Center (MAVERIC), Jamaica Plain, Massachusetts.,Department of Medicine, Harvard University, Boston, Massachusetts
| | - John Concato
- Clinical Epidemiology Research Center (CERC), VA Connecticut Healthcare System, West Haven, Connecticut.,Yale University School of Medicine, New Haven, Connecticut
| | - Hongyu Zhao
- Clinical Epidemiology Research Center (CERC), VA Connecticut Healthcare System, West Haven, Connecticut.,Yale University School of Medicine, New Haven, Connecticut
| | - Larry J Siever
- James J. Peters Veterans Affairs Medical Center, Bronx, New York.,Department of Psychiatry, Mount Sinai School of Medicine, New York, New York
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28
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Brown AS, Meera P, Quinones G, Magri J, Otis TS, Pulst SM, Oro AE. Receptor protein tyrosine phosphatases control Purkinje neuron firing. Cell Cycle 2020; 19:153-159. [PMID: 31876231 PMCID: PMC6961678 DOI: 10.1080/15384101.2019.1695995] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 10/23/2019] [Accepted: 11/07/2019] [Indexed: 10/25/2022] Open
Abstract
Spinocerebellar ataxias (SCA) are a genetically heterogeneous family of cerebellar neurodegenerative diseases characterized by abnormal firing of Purkinje neurons and degeneration. We recently demonstrated the slowed firing rates seen in several SCAs share a common etiology of hyper-activation of the Src family of non-receptor tyrosine kinases (SFKs). However, the lack of clinically available neuroactive SFK inhibitors lead us to investigate alternative mechanisms to modulate SFK activity. Previous studies demonstrate that SFK activity can be enhanced by the removal of inhibitory phospho-marks by receptor-protein-tyrosine phosphatases (RPTPs). In this Extra View we show that MTSS1 inhibits SFK activity through the binding and inhibition of a subset of the RPTP family members, and lowering RPTP activity in cerebellar slices with peptide inhibitors increases the suppressed Purkinje neuron basal firing rates seen in two different SCA models. Together these results identify RPTPs as novel effectors of Purkinje neuron basal firing, extending the MTSS1/SFK regulatory circuit we previously described and expanding the therapeutic targets for SCA patients.
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Affiliation(s)
- Alexander S. Brown
- Program in Epithelial Biology, Stanford University School of Medicine, Stanford, CA, USA
| | - Pratap Meera
- Department of Neurobiology, University of California, Los Angeles, CA, USA
| | - Gabe Quinones
- Program in Epithelial Biology, Stanford University School of Medicine, Stanford, CA, USA
| | - Jessica Magri
- Program in Epithelial Biology, Stanford University School of Medicine, Stanford, CA, USA
| | - Thomas S. Otis
- Sainsbury Wellcome Centre for Neural Circuits and Behavior, University College London, London, UK
| | - Stefan M. Pulst
- Department of Neurology, University of Utah Medical Center, Salt Lake City, UT, USA
| | - Anthony E. Oro
- Program in Epithelial Biology, Stanford University School of Medicine, Stanford, CA, USA
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29
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Breuer A, Lauritsen L, Bertseva E, Vonkova I, Stamou D. Quantitative investigation of negative membrane curvature sensing and generation by I-BARs in filopodia of living cells. SOFT MATTER 2019; 15:9829-9839. [PMID: 31728468 DOI: 10.1039/c9sm01185d] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Membrane curvature has recently been recognized as an active regulator of cellular function, with several protein families identified as sensors and generators of membrane curvature. Amongst them, the inverse Bin/Amphiphysin/Rvs (I-BAR) domain family has been implicated in the sensing and generation of membrane structures with negative membrane curvature e.g. filopodia or dendritic spines. However, to date, quantitative biophysical investigations of I-BAR domains have mostly taken place in reconstitution. Here, we use fluorescence microscopy to quantitatively investigate membrane curvature sensing and generation by I-BARs in filopodia of living cells. As a model system, we selected two prototypic members of the I-BAR family, the insulin receptor substrate p53 and missing-in-metastasis. Our data demonstrated how I-BARs sense negative membrane curvature in the complex environment of live cells by revealing a dependence on membrane curvature for both their binding affinity to membranes and their saturation density. The non-monotonic dependence of protein sorting with negative membrane curvature allowed us to apply previously developed thermodynamic models to provide estimates of the effective intrinsic curvature and bending rigidity of the two I-BARs bound at the plasma membrane. Our results agree with studies performed on the insulin receptor substrate p53 in reconstitution. To quantitate membrane curvature generation by I-BARs we measured how their overexpression reduces the peak and the width of the size distribution of filopodia, resulting in filopodia populations with smaller and more uniform diameters. Our findings provide a quantitative biophysical insight in the ability of I-BARs to sense and generate negative membrane curvature in the crowded environment of living cells.
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Affiliation(s)
- Artù Breuer
- Bionanotechnology and Nanomedicine Laboratory, Nano-Science Center, Department of Chemistry, University of Copenhagen, Copenhagen, Denmark.
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30
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Minkeviciene R, Hlushchenko I, Virenque A, Lahti L, Khanal P, Rauramaa T, Koistinen A, Leinonen V, Noe FM, Hotulainen P. MIM-Deficient Mice Exhibit Anatomical Changes in Dendritic Spines, Cortex Volume and Brain Ventricles, and Functional Changes in Motor Coordination and Learning. Front Mol Neurosci 2019; 12:276. [PMID: 31803019 PMCID: PMC6872969 DOI: 10.3389/fnmol.2019.00276] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Accepted: 10/29/2019] [Indexed: 11/13/2022] Open
Abstract
In this study, we performed a comprehensive behavioral and anatomical analysis of the Missing in Metastasis (Mtss1/MIM) knockout (KO) mouse brain. We also analyzed the expression of MIM in different brain regions at different ages. MIM is an I-BAR containing membrane curving protein, shown to be involved in dendritic spine initiation and dendritic branching in Purkinje cells in the cerebellum. Behavioral analysis of MIM KO mice revealed defects in both learning and reverse-learning, alterations in anxiety levels and reduced dominant behavior, and confirmed the previously described deficiency in motor coordination and pre-pulse inhibition. Anatomically, we observed enlarged brain ventricles and decreased cortical volume. Although MIM expression was relatively low in hippocampus after early development, hippocampal pyramidal neurons exhibited reduced density of thin and stubby dendritic spines. Learning deficiencies can be connected to all detected anatomical changes. Both behavioral and anatomical findings are typical for schizophrenia mouse models.
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Affiliation(s)
| | - Iryna Hlushchenko
- Minerva Foundation Institute for Medical Research, Helsinki, Finland
| | - Anaïs Virenque
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
- HiLIFE - Neuroscience Center, University of Helsinki, Helsinki, Finland
| | - Lauri Lahti
- Department of Computer Science, Aalto University School of Science, Espoo, Finland
| | - Pushpa Khanal
- Minerva Foundation Institute for Medical Research, Helsinki, Finland
- HiLIFE - Neuroscience Center, University of Helsinki, Helsinki, Finland
| | - Tuomas Rauramaa
- Department of Clinical Pathology, Kuopio University Hospital, University of Eastern Finland, Kuopio, Finland
| | - Arto Koistinen
- SIB Labs Infrastructure Unit, University of Eastern Finland, Kuopio, Finland
| | - Ville Leinonen
- Neurosurgery of NeuroCenter, Kuopio University Hospital, University of Eastern Finland (UEF), Kuopio, Finland
- Research Unit of Clinical Neuroscience, University of Oulu, Oulu, Finland
- Department of Neurosurgery, MRC Oulu, Oulu University Hospital, Oulu, Finland
| | - Francesco M. Noe
- A. I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, Kuopio, Finland
- HiLIFE - Neuroscience Center, University of Helsinki, Helsinki, Finland
| | - Pirta Hotulainen
- Minerva Foundation Institute for Medical Research, Helsinki, Finland
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31
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Roesler MK, Lombino FL, Freitag S, Schweizer M, Hermans-Borgmeyer I, Schwarz JR, Kneussel M, Wagner W. Myosin XVI Regulates Actin Cytoskeleton Dynamics in Dendritic Spines of Purkinje Cells and Affects Presynaptic Organization. Front Cell Neurosci 2019; 13:330. [PMID: 31474830 PMCID: PMC6705222 DOI: 10.3389/fncel.2019.00330] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Accepted: 07/04/2019] [Indexed: 11/29/2022] Open
Abstract
The actin cytoskeleton is crucial for function and morphology of neuronal synapses. Moreover, altered regulation of the neuronal actin cytoskeleton has been implicated in neuropsychiatric diseases such as autism spectrum disorder (ASD). Myosin XVI is a neuronally expressed unconventional myosin known to bind the WAVE regulatory complex (WRC), a regulator of filamentous actin (F-actin) polymerization. Notably, the gene encoding the myosin’s heavy chain (MYO16) shows genetic association with neuropsychiatric disorders including ASD. Here, we investigated whether myosin XVI plays a role for actin cytoskeleton regulation in the dendritic spines of cerebellar Purkinje cells (PCs), a neuronal cell type crucial for motor learning, social cognition and vocalization. We provide evidence that both myosin XVI and the WRC component WAVE1 localize to PC spines. Fluorescence recovery after photobleaching (FRAP) analysis of GFP-actin in cultured PCs shows that Myo16 knockout as well as PC-specific Myo16 knockdown, lead to faster F-actin turnover in the dendritic spines of PCs. We also detect accelerated F-actin turnover upon interference with the WRC, and upon inhibition of Arp2/3 that drives formation of branched F-actin downstream of the WRC. In contrast, inhibition of formins that are responsible for polymerization of linear actin filaments does not cause faster F-actin turnover. Together, our data establish myosin XVI as a regulator of the postsynaptic actin cytoskeleton and suggest that it is an upstream activator of the WRC-Arp2/3 pathway in PC spines. Furthermore, ultra-structural and electrophysiological analyses of Myo16 knockout cerebellum reveals the presence of reduced numbers of synaptic vesicles at presynaptic terminals in the absence of the myosin. Therefore, we here define myosin XVI as an F-actin regulator important for presynaptic organization in the cerebellum.
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Affiliation(s)
- Mona Katrin Roesler
- Department of Molecular Neurogenetics, Center for Molecular Neurobiology Hamburg, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Franco Luis Lombino
- Department of Molecular Neurogenetics, Center for Molecular Neurobiology Hamburg, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Sandra Freitag
- Department of Molecular Neurogenetics, Center for Molecular Neurobiology Hamburg, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Michaela Schweizer
- Electron Microscopy Unit, Center for Molecular Neurobiology Hamburg, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Irm Hermans-Borgmeyer
- Transgenic Animal Unit, Center for Molecular Neurobiology Hamburg, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jürgen R Schwarz
- Department of Molecular Neurogenetics, Center for Molecular Neurobiology Hamburg, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Matthias Kneussel
- Department of Molecular Neurogenetics, Center for Molecular Neurobiology Hamburg, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Wolfgang Wagner
- Department of Molecular Neurogenetics, Center for Molecular Neurobiology Hamburg, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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32
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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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Chatzi C, Zhang Y, Hendricks WD, Chen Y, Schnell E, Goodman RH, Westbrook GL. Exercise-induced enhancement of synaptic function triggered by the inverse BAR protein, Mtss1L. eLife 2019; 8:45920. [PMID: 31232686 PMCID: PMC6609409 DOI: 10.7554/elife.45920] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Accepted: 06/22/2019] [Indexed: 01/11/2023] Open
Abstract
Exercise is a potent enhancer of learning and memory, yet we know little of the underlying mechanisms that likely include alterations in synaptic efficacy in the hippocampus. To address this issue, we exposed mice to a single episode of voluntary exercise, and permanently marked activated mature hippocampal dentate granule cells using conditional Fos-TRAP mice. Exercise-activated neurons (Fos-TRAPed) showed an input-selective increase in dendritic spines and excitatory postsynaptic currents at 3 days post-exercise, indicative of exercise-induced structural plasticity. Laser-capture microdissection and RNASeq of activated neurons revealed that the most highly induced transcript was Mtss1L, a little-studied I-BAR domain-containing gene, which we hypothesized could be involved in membrane curvature and dendritic spine formation. shRNA-mediated Mtss1L knockdown in vivo prevented the exercise-induced increases in spines and excitatory postsynaptic currents. Our results link short-term effects of exercise to activity-dependent expression of Mtss1L, which we propose as a novel effector of activity-dependent rearrangement of synapses.
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Affiliation(s)
- Christina Chatzi
- Vollum Institute, Oregon Health & Science University, Portland, United States
| | - Yingyu Zhang
- Vollum Institute, Oregon Health & Science University, Portland, United States
| | - Wiiliam D Hendricks
- Vollum Institute, Oregon Health & Science University, Portland, United States.,Neuroscience Graduate Program, Vollum Institute, Oregon Health & Science University, Portland, United States
| | - Yang Chen
- Vollum Institute, Oregon Health & Science University, Portland, United States.,Neuroscience Graduate Program, Vollum Institute, Oregon Health & Science University, Portland, United States
| | - Eric Schnell
- Department of Anesthesiology and Perioperative Medicine, Oregon Health & Science University, Portland, United States.,Portland VA Health Care System, Portland, United States
| | - Richard H Goodman
- Vollum Institute, Oregon Health & Science University, Portland, United States
| | - Gary L Westbrook
- Vollum Institute, Oregon Health & Science University, Portland, United States
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Drab M, Stopar D, Kralj-Iglič V, Iglič A. Inception Mechanisms of Tunneling Nanotubes. Cells 2019; 8:cells8060626. [PMID: 31234435 PMCID: PMC6627088 DOI: 10.3390/cells8060626] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Revised: 06/18/2019] [Accepted: 06/18/2019] [Indexed: 01/13/2023] Open
Abstract
Tunneling nanotubes (TNTs) are thin membranous tubes that interconnect cells, representing a novel route of cell-to-cell communication and spreading of pathogens. TNTs form between many cell types, yet their inception mechanisms remain elusive. We review in this study general concepts related to the formation and stability of membranous tubular structures with a focus on a deviatoric elasticity model of membrane nanodomains. We review experimental evidence that tubular structures initiate from local membrane bending facilitated by laterally distributed proteins or anisotropic membrane nanodomains. We further discuss the numerical results of several theoretical and simulation models of nanodomain segregation suggesting the mechanisms of TNT inception and stability. We discuss the coupling of nanodomain segregation with the action of protruding cytoskeletal forces, which are mostly provided in eukaryotic cells by the polymerization of f-actin, and review recent inception mechanisms of TNTs in relation to motor proteins.
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Affiliation(s)
- Mitja Drab
- Laboratory of Physics, Faculty of Electrical Engineering, University of Ljubljana,1000 Ljubljana, Slovenia.
- Laboratory of Clinical Biophysics, Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia.
| | - David Stopar
- Department of Food Science and Technology, Biotechnical Faculty, University of Ljubljana, 1000 Ljubljana, Slovenia.
| | - Veronika Kralj-Iglič
- Laboratory of Clinical Biophysics, Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia.
- Laboratory of Clinical Biophysics, Faculty of Health Sciences, University of Ljubljana, 1000 Ljubljana, Slovenia.
| | - Aleš Iglič
- Laboratory of Physics, Faculty of Electrical Engineering, University of Ljubljana,1000 Ljubljana, Slovenia.
- Laboratory of Clinical Biophysics, Faculty of Medicine, University of Ljubljana, 1000 Ljubljana, Slovenia.
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Stürner T, Tatarnikova A, Mueller J, Schaffran B, Cuntz H, Zhang Y, Nemethova M, Bogdan S, Small V, Tavosanis G. Transient localization of the Arp2/3 complex initiates neuronal dendrite branching in vivo. Development 2019; 146:dev.171397. [PMID: 30910826 DOI: 10.1242/dev.171397] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 03/08/2019] [Indexed: 01/02/2023]
Abstract
The formation of neuronal dendrite branches is fundamental for the wiring and function of the nervous system. Indeed, dendrite branching enhances the coverage of the neuron's receptive field and modulates the initial processing of incoming stimuli. Complex dendrite patterns are achieved in vivo through a dynamic process of de novo branch formation, branch extension and retraction. The first step towards branch formation is the generation of a dynamic filopodium-like branchlet. The mechanisms underlying the initiation of dendrite branchlets are therefore crucial to the shaping of dendrites. Through in vivo time-lapse imaging of the subcellular localization of actin during the process of branching of Drosophila larva sensory neurons, combined with genetic analysis and electron tomography, we have identified the Actin-related protein (Arp) 2/3 complex as the major actin nucleator involved in the initiation of dendrite branchlet formation, under the control of the activator WAVE and of the small GTPase Rac1. Transient recruitment of an Arp2/3 component marks the site of branchlet initiation in vivo These data position the activation of Arp2/3 as an early hub for the initiation of branchlet formation.
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Affiliation(s)
- Tomke Stürner
- Deutsches Zentrum für Neurodegenerative Erkrankungen e.V./German Center for Neurodegenerative Diseases (DZNE), 53127 Bonn, Germany
| | - Anastasia Tatarnikova
- Deutsches Zentrum für Neurodegenerative Erkrankungen e.V./German Center for Neurodegenerative Diseases (DZNE), 53127 Bonn, Germany.,MPI for Neurobiology, 82152 Munich- Martinsried, Germany
| | - Jan Mueller
- Institute of Molecular biotechnology (IMBA), 1030 Wien, Austria
| | - Barbara Schaffran
- Deutsches Zentrum für Neurodegenerative Erkrankungen e.V./German Center for Neurodegenerative Diseases (DZNE), 53127 Bonn, Germany
| | - Hermann Cuntz
- Ernst Strüngmann Institute (ESI) for Neuroscience in Cooperation with Max Planck Society, 60528 Frankfurt, Germany.,Frankfurt Institute for Advanced Studies, 60438 Frankfurt, Germany
| | - Yun Zhang
- Deutsches Zentrum für Neurodegenerative Erkrankungen e.V./German Center for Neurodegenerative Diseases (DZNE), 53127 Bonn, Germany
| | - Maria Nemethova
- Institute of Molecular biotechnology (IMBA), 1030 Wien, Austria
| | - Sven Bogdan
- Institut für Physiologie und Pathophysiologie, Abteilung Molekulare Zellphysiologie, Phillips-Universität Marburg, 35037 Marburg, Germany
| | - Vic Small
- Institute of Molecular biotechnology (IMBA), 1030 Wien, Austria
| | - Gaia Tavosanis
- Deutsches Zentrum für Neurodegenerative Erkrankungen e.V./German Center for Neurodegenerative Diseases (DZNE), 53127 Bonn, Germany
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36
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Petrov P, Sarapulov AV, Eöry L, Scielzo C, Scarfò L, Smith J, Burt DW, Mattila PK. Computational analysis of the evolutionarily conserved Missing In Metastasis/Metastasis Suppressor 1 gene predicts novel interactions, regulatory regions and transcriptional control. Sci Rep 2019; 9:4155. [PMID: 30858428 PMCID: PMC6411742 DOI: 10.1038/s41598-019-40697-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2018] [Accepted: 02/21/2019] [Indexed: 12/25/2022] Open
Abstract
Missing in Metastasis (MIM), or Metastasis Suppressor 1 (MTSS1), is a highly conserved protein, which links the plasma membrane to the actin cytoskeleton. MIM has been implicated in various cancers, however, its modes of action remain largely enigmatic. Here, we performed an extensive in silico characterisation of MIM to gain better understanding of its function. We detected previously unappreciated functional motifs including adaptor protein (AP) complex interaction site and a C-helix, pointing to a role in endocytosis and regulation of actin dynamics, respectively. We also identified new functional regions, characterised with phosphorylation sites or distinct hydrophilic properties. Strong negative selection during evolution, yielding high conservation of MIM, has been combined with positive selection at key sites. Interestingly, our analysis of intra-molecular co-evolution revealed potential regulatory hotspots that coincided with reduced potentially pathogenic polymorphisms. We explored databases for the mutations and expression levels of MIM in cancer. Experimentally, we focused on chronic lymphocytic leukaemia (CLL), where MIM showed high overall expression, however, downregulation on poor prognosis samples. Finally, we propose strong conservation of MTSS1 also on the transcriptional level and predict novel transcriptional regulators. Our data highlight important targets for future studies on the role of MIM in different tissues and cancers.
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Affiliation(s)
- Petar Petrov
- Institute of Biomedicine, and MediCity Research Laboratories, University of Turku, Tykistökatu 6A, 20520, Turku, Finland.
| | - Alexey V Sarapulov
- Institute of Biomedicine, and MediCity Research Laboratories, University of Turku, Tykistökatu 6A, 20520, Turku, Finland
| | - Lel Eöry
- Division of Genetics and Genomics, The Roslin Institute and R(D)SVS, University of Edinburgh, Roslin, Easter Bush campus, Midlothian, EH25 9RG, United Kingdom
| | - Cristina Scielzo
- Unit of B Cell Neoplasia, Division of Molecular Oncology, IRCCS, San Raffaele Scientific Institute, Milano, Italy.,Università Vita-Salute San Raffaele, Milan, Italy
| | - Lydia Scarfò
- Unit of B Cell Neoplasia, Division of Molecular Oncology, IRCCS, San Raffaele Scientific Institute, Milano, Italy.,Università Vita-Salute San Raffaele, Milan, Italy.,Strategic Research Program on CLL, Division of Experimental Oncology, IRCCS, San Raffaele Scientific Institute, Milano, Italy
| | - Jacqueline Smith
- Division of Genetics and Genomics, The Roslin Institute and R(D)SVS, University of Edinburgh, Roslin, Easter Bush campus, Midlothian, EH25 9RG, United Kingdom
| | - David W Burt
- University of Queensland, St. Lucia, QLD, 4072, Australia
| | - Pieta K Mattila
- Institute of Biomedicine, and MediCity Research Laboratories, University of Turku, Tykistökatu 6A, 20520, Turku, Finland.
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Li L, Baxter SS, Zhao P, Gu N, Zhan X. Differential interactions of missing in metastasis and insulin receptor tyrosine kinase substrate with RAB proteins in the endocytosis of CXCR4. J Biol Chem 2019; 294:6494-6505. [PMID: 30808710 DOI: 10.1074/jbc.ra118.006071] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Revised: 02/15/2019] [Indexed: 12/26/2022] Open
Abstract
Missing in metastasis (MIM), an inverse Bin-Amphiphysin-Rvs (I-BAR) domain protein, promotes endocytosis of C-X-C chemokine receptor 4 (CXCR4) in mammalian cells. In response to the CXCR4 ligand stromal cell-derived factor 1 (SDF-1 or CXCL12), MIM associates with RAS-related GTP-binding protein 7 (RAB7) 30 min after stimulation. However, RAB7's role in MIM function remains undefined. Here we show that RNAi-mediated suppression of RAB7 expression in human HeLa cells has little effect on the binding of MIM to RAB5 and on the recruitment of CXCR4 to early endosomes but effectively abolishes MIM-mediated CXCR4 degradation, chemotactic response, and sorting into late endosomes and lysosomes. To determine whether I-BAR domain proteins interact with RAB7, we examined cells expressing insulin receptor tyrosine kinase substrate (IRTKS), an I-BAR domain protein bearing an Src homology 3 (SH3) domain. We observed that both MIM and IRTKS interact with RAB5 at an early response to SDF-1 and that IRTKS binds poorly to RAB7 but strongly to RAB11 at a later time point. Moreover, IRTKS overexpression reduced CXCR4 internalization and enhanced the chemotactic response to SDF-1. Interestingly, deletion of the SH3 domain in IRTKS abolished the IRTKS-RAB11 interaction and promoted CXCR4 degradation. Furthermore, the SH3 domain was required for selective targeting of MIM-IRTKS fusion proteins by both RAB7 and RAB11. Hence, to the best of our knowledge, our results provide first evidence that the SH3 domain is critical in the regulation of specific endocytic pathways by I-BAR domain proteins.
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Affiliation(s)
- Lushen Li
- From the Center for Vascular and Inflammatory Diseases
| | | | - Peng Zhao
- the State Key Laboratory of Bioelectronics, Jiangsu Key Laboratory for Biomaterials and Devices, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Ning Gu
- the State Key Laboratory of Bioelectronics, Jiangsu Key Laboratory for Biomaterials and Devices, School of Biological Science and Medical Engineering, Southeast University, Nanjing 210096, China
| | - Xi Zhan
- From the Center for Vascular and Inflammatory Diseases, .,Department of Pathology, and.,University of Maryland Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland School of Medicine, Baltimore, Maryland 21201 and
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MTSS1/Src family kinase dysregulation underlies multiple inherited ataxias. Proc Natl Acad Sci U S A 2018; 115:E12407-E12416. [PMID: 30530649 DOI: 10.1073/pnas.1816177115] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The genetically heterogeneous spinocerebellar ataxias (SCAs) are caused by Purkinje neuron dysfunction and degeneration, but their underlying pathological mechanisms remain elusive. The Src family of nonreceptor tyrosine kinases (SFK) are essential for nervous system homeostasis and are increasingly implicated in degenerative disease. Here we reveal that the SFK suppressor Missing-in-metastasis (MTSS1) is an ataxia locus that links multiple SCAs. MTSS1 loss results in increased SFK activity, reduced Purkinje neuron arborization, and low basal firing rates, followed by cell death. Surprisingly, mouse models for SCA1, SCA2, and SCA5 show elevated SFK activity, with SCA1 and SCA2 displaying dramatically reduced MTSS1 protein levels through reduced gene expression and protein translation, respectively. Treatment of each SCA model with a clinically approved Src inhibitor corrects Purkinje neuron basal firing and delays ataxia progression in MTSS1 mutants. Our results identify a common SCA therapeutic target and demonstrate a key role for MTSS1/SFK in Purkinje neuron survival and ataxia progression.
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39
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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: 90] [Impact Index Per Article: 15.0] [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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40
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Postema MM, Grega-Larson NE, Neininger AC, Tyska MJ. IRTKS (BAIAP2L1) Elongates Epithelial Microvilli Using EPS8-Dependent and Independent Mechanisms. Curr Biol 2018; 28:2876-2888.e4. [PMID: 30197089 DOI: 10.1016/j.cub.2018.07.022] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 06/05/2018] [Accepted: 07/09/2018] [Indexed: 11/24/2022]
Abstract
Transporting epithelial cells like those that line the gut build large arrays of actin-supported protrusions called microvilli, which extend from the apical surface into luminal spaces to increase functional surface area. Although critical for maintaining physiological homeostasis, mechanisms controlling the formation of microvilli remain poorly understood. Here, we report that the inverse-bin-amphiphysin-Rvs (I-BAR)-domain-containing protein insulin receptor tyrosine kinase substrate (IRTKS) (also known as BAIAP2L1) promotes the growth of epithelial microvilli. Super-resolution microscopy and live imaging of differentiating epithelial cells revealed that IRTKS localizes to the distal tips of actively growing microvilli via a mechanism that requires its N-terminal I-BAR domain. At microvillar tips, IRTKS promotes elongation through a mechanism involving its C-terminal actin-binding WH2 domain. IRTKS can also drive microvillar elongation using its SH3 domain to recruit the bundling protein EPS8 to microvillar tips. These results provide new insight on mechanisms that control microvillar growth during the differentiation of transporting epithelial cells and help explain why IRTKS is targeted by enteric pathogens that disrupt microvillar structure during infection of the intestinal epithelium.
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Affiliation(s)
- Meagan M Postema
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Nathan E Grega-Larson
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Abigail C Neininger
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA
| | - Matthew J Tyska
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA.
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41
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Yuan Y, Xie S, Darnell JC, Darnell AJ, Saito Y, Phatnani H, Murphy EA, Zhang C, Maniatis T, Darnell RB. Cell type-specific CLIP reveals that NOVA regulates cytoskeleton interactions in motoneurons. Genome Biol 2018; 19:117. [PMID: 30111345 PMCID: PMC6092797 DOI: 10.1186/s13059-018-1493-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 07/24/2018] [Indexed: 12/30/2022] Open
Abstract
Background Alternative RNA processing plays an essential role in shaping cell identity and connectivity in the central nervous system. This is believed to involve differential regulation of RNA processing in various cell types. However, in vivo study of cell type-specific post-transcriptional regulation has been a challenge. Here, we describe a sensitive and stringent method combining genetics and CLIP (crosslinking and immunoprecipitation) to globally identify regulatory interactions between NOVA and RNA in the mouse spinal cord motoneurons. Results We developed a means of undertaking motoneuron-specific CLIP to explore motoneuron-specific protein–RNA interactions relative to studies of the whole spinal cord in mouse. This allowed us to pinpoint differential RNA regulation specific to motoneurons, revealing a major role for NOVA in regulating cytoskeleton interactions in motoneurons. In particular, NOVA specifically promotes the palmitoylated isoform of the cytoskeleton protein Septin 8 in motoneurons, which enhances dendritic arborization. Conclusions Our study demonstrates that cell type-specific RNA regulation is important for fine tuning motoneuron physiology and highlights the value of defining RNA processing regulation at single cell type resolution. Electronic supplementary material The online version of this article (10.1186/s13059-018-1493-2) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Yuan Yuan
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, 1230 York Ave., New York, NY, 10065, USA
| | - Shirley Xie
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, 1230 York Ave., New York, NY, 10065, USA
| | - Jennifer C Darnell
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, 1230 York Ave., New York, NY, 10065, USA
| | - Andrew J Darnell
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, 1230 York Ave., New York, NY, 10065, USA
| | - Yuhki Saito
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, 1230 York Ave., New York, NY, 10065, USA
| | - Hemali Phatnani
- New York Genome Center, 101 Avenue of the Americas, New York, NY, 10013, USA.,Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, 10032, USA
| | - Elisabeth A Murphy
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, 1230 York Ave., New York, NY, 10065, USA
| | - Chaolin Zhang
- Department of Systems Biology, Columbia University, New York, NY, 10032, USA.,Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, 10032, USA.,Center for Motor Neuron Biology and Disease, Columbia University, New York, NY, 10032, USA
| | - Tom Maniatis
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, NY, 10032, USA.,Center for Motor Neuron Biology and Disease, Columbia University, New York, NY, 10032, USA
| | - Robert B Darnell
- Laboratory of Molecular Neuro-Oncology, The Rockefeller University, 1230 York Ave., New York, NY, 10065, USA. .,Howard Hughes Medical Institute, The Rockefeller University, 1230 York Ave., New York, NY, 10065, USA.
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Nithianandam V, Chien CT. Actin blobs prefigure dendrite branching sites. J Cell Biol 2018; 217:3731-3746. [PMID: 30042190 PMCID: PMC6168249 DOI: 10.1083/jcb.201711136] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 03/28/2018] [Accepted: 07/09/2018] [Indexed: 02/08/2023] Open
Abstract
Nithianandam and Chien show via in vivo imaging that a dynamic population of F-actin termed actin blobs propagates bidirectionally in dendrites and stalls at future branching sites. The F-actin–severing protein Tsr/cofilin is a regulator of actin blob dynamics and dendrite branching. The actin cytoskeleton provides structural stability and adaptability to the cell. Neuronal dendrites frequently undergo morphological changes by emanating, elongating, and withdrawing branches. However, the knowledge about actin dynamics in dendrites during these processes is limited. By performing in vivo imaging of F-actin markers, we found that F-actin was highly dynamic and heterogeneously distributed in dendritic shafts with enrichment at terminal dendrites. A dynamic F-actin population that we named actin blobs propagated bidirectionally at an average velocity of 1 µm/min. Interestingly, these actin blobs stalled at sites where new dendrites would branch out in minutes. Overstabilization of F-actin by the G15S mutant abolished actin blobs and dendrite branching. We identified the F-actin–severing protein Tsr/cofilin as a regulator of dynamic actin blobs and branching activity. Hence, actin blob localization at future branching sites represents a dendrite-branching mechanism to account for highly diversified dendritic morphology.
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Affiliation(s)
- Vanitha Nithianandam
- Molecular and Cell Biology, Taiwan International Graduate Program, Academia Sinica and Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan.,Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Cheng-Ting Chien
- Molecular and Cell Biology, Taiwan International Graduate Program, Academia Sinica and Graduate Institute of Life Sciences, National Defense Medical Center, Taipei, Taiwan .,Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
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Kawabata Galbraith K, Fujishima K, Mizuno H, Lee SJ, Uemura T, Sakimura K, Mishina M, Watanabe N, Kengaku M. MTSS1 Regulation of Actin-Nucleating Formin DAAM1 in Dendritic Filopodia Determines Final Dendritic Configuration of Purkinje Cells. Cell Rep 2018; 24:95-106.e9. [DOI: 10.1016/j.celrep.2018.06.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 05/01/2018] [Accepted: 06/01/2018] [Indexed: 10/28/2022] Open
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44
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Membrane re-modelling by BAR domain superfamily proteins via molecular and non-molecular factors. Biochem Soc Trans 2018. [PMID: 29540508 DOI: 10.1042/bst20170322] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Lipid membranes are structural components of cell surfaces and intracellular organelles. Alterations in lipid membrane shape are accompanied by numerous cellular functions, including endocytosis, intracellular transport, and cell migration. Proteins containing Bin-Amphiphysin-Rvs (BAR) domains (BAR proteins) are unique, because their structures correspond to the membrane curvature, that is, the shape of the lipid membrane. BAR proteins present at high concentration determine the shape of the membrane, because BAR domain oligomers function as scaffolds that mould the membrane. BAR proteins co-operate with various molecular and non-molecular factors. The molecular factors include cytoskeletal proteins such as the regulators of actin filaments and the membrane scission protein dynamin. Lipid composition, including saturated or unsaturated fatty acid tails of phospholipids, also affects the ability of BAR proteins to mould the membrane. Non-molecular factors include the external physical forces applied to the membrane, such as tension and friction. In this mini-review, we will discuss how the BAR proteins orchestrate membrane dynamics together with various molecular and non-molecular factors.
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45
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Huang XY, Huang ZL, Niu T, Wu ZQ, Xu B, Xu YH, Huang XY, Zheng Q, Zhou J, Chen Z, Tang ZY. Missing-in-metastasis B (MIM-B) combined with caveolin-1 promotes metastasis of hepatocellular carcinoma. Oncotarget 2017; 8:95450-95465. [PMID: 29221140 PMCID: PMC5707034 DOI: 10.18632/oncotarget.20735] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 08/04/2017] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND Increasing amounts of evidence indicate that Missing in metastasis B (MIM-B) promotes cancer metastasis. Here, we sought to better understand the mechanism through which MIM-B promotes tumor metastasis in hepatocellular carcinoma (HCC). METHODS We performed confocal microscopy analysis to determine the distributions of MIM-B and caveolin-1 and conducted co-immunoprecipitation assays to detect the interactions between MIM-B and caveolin-1 in vitro. We performed transwell assays to analyze the invasive ability of HCC cells. Changes in the expression levels of key genes and some molecular makers were detected by immunohistochemistry and western blotting in HCC tissue samples. RESULTS We found that MIM-B co-localizes with caveolin-1 and demonstrated that MIM-B and caveolin-1 interact in vitro. Repressing MIM-B and caveolin-1 expression inhibited the epidermal growth factor receptor signaling pathway. We overexpressed MIM-B and caveolin-1 in Hep3B cells, which enhanced Hep3B cell invasiveness. Furthermore, MHCC97H cell invasiveness was significantly decreased in cells in which MIM-B and caveolin-1 expression was inhibited. Additionally, we found that MIM-B and caveolin-1 were expressed at higher levels in HCC tissues than in paired normal tissues. Moreover, HCC patients with MIM-B and caveolin-1 up-regulation experienced significantly worse outcomes than controls (P < 0.001), and HCC patients with high MIM-B and caveolin-1 expression levels often developed pulmonary metastasis (P < 0.001). CONCLUSIONS MIM-B combined with caveolin-1 promotes metastasis of HCC, and elevated MIM-B and caveolin-1 expression levels are associated with a poor prognosis in HCC patients; therefore, MIM-B and caveolin-1 may represent novel targets for the diagnosis and treatment of HCC.
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Affiliation(s)
- Xiu-Yan Huang
- Department of General Surgery, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai, P.R. China
| | - Zi-Li Huang
- Department of Radiology, Xuhui Central Hospital, Shanghai, P.R. China
| | - Tao Niu
- Department of General Surgery, People's Hospital of Menghai County, Yunnan Province, P.R. China
| | - Zhen-Qian Wu
- Department of General Surgery, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai, P.R. China
| | - Bin Xu
- Department of General Surgery, The Tenth People's Hospital of Tongji University, Shanghai, P.R. China
| | - Yong-Hua Xu
- Department of Radiology, Xuhui Central Hospital, Shanghai, P.R. China
| | - Xin-Yu Huang
- Department of General Surgery, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai, P.R. China
| | - Qi Zheng
- Department of General Surgery, Shanghai Jiaotong University Affiliated Sixth People's Hospital, Shanghai, P.R. China
| | - Jian Zhou
- Liver Cancer Institute and Zhongshan Hospital, Fudan University, Shanghai, P.R. China
| | - Zi Chen
- Thayer School of Engineering, Norris Cotton Cancer Center, Dartmouth College, Hanover, NH, USA
| | - Zhao-You Tang
- Liver Cancer Institute and Zhongshan Hospital, Fudan University, Shanghai, P.R. China
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Mechanistic principles underlying regulation of the actin cytoskeleton by phosphoinositides. Proc Natl Acad Sci U S A 2017; 114:E8977-E8986. [PMID: 29073094 DOI: 10.1073/pnas.1705032114] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The actin cytoskeleton powers membrane deformation during many cellular processes, such as migration, morphogenesis, and endocytosis. Membrane phosphoinositides, especially phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2], regulate the activities of many actin-binding proteins (ABPs), including profilin, cofilin, Dia2, N-WASP, ezrin, and moesin, but the underlying molecular mechanisms have remained elusive. Moreover, because of a lack of available methodology, the dynamics of membrane interactions have not been experimentally determined for any ABP. Here, we applied a combination of biochemical assays, photobleaching/activation approaches, and atomistic molecular dynamics simulations to uncover the molecular principles by which ABPs interact with phosphoinositide-rich membranes. We show that, despite using different domains for lipid binding, these proteins associate with membranes through similar multivalent electrostatic interactions, without specific binding pockets or penetration into the lipid bilayer. Strikingly, our experiments reveal that these proteins display enormous differences in the dynamics of membrane interactions and in the ranges of phosphoinositide densities that they sense. Profilin and cofilin display transient, low-affinity interactions with phosphoinositide-rich membranes, whereas F-actin assembly factors Dia2 and N-WASP reside on phosphoinositide-rich membranes for longer periods to perform their functions. Ezrin and moesin, which link the actin cytoskeleton to the plasma membrane, bind membranes with very high affinity and slow dissociation dynamics. Unlike profilin, cofilin, Dia2, and N-WASP, they do not require high "stimulus-responsive" phosphoinositide density for membrane binding. Moreover, ezrin can limit the lateral diffusion of PI(4,5)P2 along the lipid bilayer. Together, these findings demonstrate that membrane-interaction mechanisms of ABPs evolved to precisely fulfill their specific functions in cytoskeletal dynamics.
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Urbančič V, Butler R, Richier B, Peter M, Mason J, Livesey FJ, Holt CE, Gallop JL. Filopodyan: An open-source pipeline for the analysis of filopodia. J Cell Biol 2017; 216:3405-3422. [PMID: 28760769 PMCID: PMC5626553 DOI: 10.1083/jcb.201705113] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Revised: 06/28/2017] [Accepted: 07/06/2017] [Indexed: 02/07/2023] Open
Abstract
Filopodia have important sensory and mechanical roles in motile cells. The recruitment of actin regulators, such as ENA/VASP proteins, to sites of protrusion underlies diverse molecular mechanisms of filopodia formation and extension. We developed Filopodyan (filopodia dynamics analysis) in Fiji and R to measure fluorescence in filopodia and at their tips and bases concurrently with their morphological and dynamic properties. Filopodyan supports high-throughput phenotype characterization as well as detailed interactive editing of filopodia reconstructions through an intuitive graphical user interface. Our highly customizable pipeline is widely applicable, capable of detecting filopodia in four different cell types in vitro and in vivo. We use Filopodyan to quantify the recruitment of ENA and VASP preceding filopodia formation in neuronal growth cones, and uncover a molecular heterogeneity whereby different filopodia display markedly different responses to changes in the accumulation of ENA and VASP fluorescence in their tips over time.
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Affiliation(s)
- Vasja Urbančič
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, England, UK
- Department of Biochemistry, University of Cambridge, Cambridge, England, UK
| | - Richard Butler
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, England, UK
| | - Benjamin Richier
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, England, UK
- Department of Biochemistry, University of Cambridge, Cambridge, England, UK
| | - Manuel Peter
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, England, UK
- Department of Biochemistry, University of Cambridge, Cambridge, England, UK
| | - Julia Mason
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, England, UK
- Department of Biochemistry, University of Cambridge, Cambridge, England, UK
| | - Frederick J Livesey
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, England, UK
- Department of Biochemistry, University of Cambridge, Cambridge, England, UK
| | - Christine E Holt
- Department of Physiology, Development, and Neuroscience, University of Cambridge, Cambridge, England, UK
| | - Jennifer L Gallop
- Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge, England, UK
- Department of Biochemistry, University of Cambridge, Cambridge, England, UK
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48
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Schludi MH, Becker L, Garrett L, Gendron TF, Zhou Q, Schreiber F, Popper B, Dimou L, Strom TM, Winkelmann J, von Thaden A, Rentzsch K, May S, Michaelsen M, Schwenk BM, Tan J, Schoser B, Dieterich M, Petrucelli L, Hölter SM, Wurst W, Fuchs H, Gailus-Durner V, de Angelis MH, Klopstock T, Arzberger T, Edbauer D. Spinal poly-GA inclusions in a C9orf72 mouse model trigger motor deficits and inflammation without neuron loss. Acta Neuropathol 2017; 134:241-254. [PMID: 28409281 PMCID: PMC5508040 DOI: 10.1007/s00401-017-1711-0] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 04/04/2017] [Accepted: 04/04/2017] [Indexed: 12/13/2022]
Abstract
Translation of the expanded (ggggcc)n repeat in C9orf72 patients with amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) causes abundant poly-GA inclusions. To elucidate their role in pathogenesis, we generated transgenic mice expressing codon-modified (GA)149 conjugated with cyan fluorescent protein (CFP). Transgenic mice progressively developed poly-GA inclusions predominantly in motoneurons and interneurons of the spinal cord and brain stem and in deep cerebellar nuclei. Poly-GA co-aggregated with p62, Rad23b and the newly identified Mlf2, in both mouse and patient samples. Consistent with the expression pattern, 4-month-old transgenic mice showed abnormal gait and progressive balance impairment, but showed normal hippocampus-dependent learning and memory. Apart from microglia activation we detected phosphorylated TDP-43 but no neuronal loss. Thus, poly-GA triggers behavioral deficits through inflammation and protein sequestration that likely contribute to the prodromal symptoms and disease progression of C9orf72 patients.
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Affiliation(s)
- Martin H Schludi
- German Center for Neurodegenerative Diseases (DZNE) Munich, Feodor-Lynen-Straße 17, 81377, Munich, Germany
- Munich Cluster for System Neurology (SyNergy), Feodor-Lynen-Straße 17, 81377, Munich, Germany
| | - Lore Becker
- German Mouse Clinic, Institute of Experimental Genetics, German Research Center for Environmental Health, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764, Neuherberg, Germany
| | - Lillian Garrett
- German Mouse Clinic, Institute of Experimental Genetics, German Research Center for Environmental Health, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764, Neuherberg, Germany
- Institute of Developmental Genetics, German Research Center for Environmental Health, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764, Neuherberg, Germany
| | - Tania F Gendron
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL, 32224, USA
| | - Qihui Zhou
- German Center for Neurodegenerative Diseases (DZNE) Munich, Feodor-Lynen-Straße 17, 81377, Munich, Germany
- Munich Cluster for System Neurology (SyNergy), Feodor-Lynen-Straße 17, 81377, Munich, Germany
| | - Franziska Schreiber
- German Center for Neurodegenerative Diseases (DZNE) Munich, Feodor-Lynen-Straße 17, 81377, Munich, Germany
| | - Bastian Popper
- Department of Anatomy and Cell Biology, Biomedical Center, Ludwig-Maximilians-University Munich, Großhaderner Str. 9, 82152, Planegg-Martinsried, Germany
| | - Leda Dimou
- Physiological Genomics, Biomedical Center, Ludwig-Maximilians-University Munich, Großhaderner Str. 9, 82152, Planegg-Martinsried, Germany
- Molecular and Translational Neuroscience, Department of Neurology, University of Ulm, Albert-Einstein-Allee 11, 89081, Ulm, Germany
| | - Tim M Strom
- Institut für Humangenetik, Helmholtz Zentrum München, 85764, Munich, Germany
| | - Juliane Winkelmann
- Munich Cluster for System Neurology (SyNergy), Feodor-Lynen-Straße 17, 81377, Munich, Germany
- Institut für Neurogenomik, Helmholtz Zentrum München, 85764, Munich, Germany
- Neurologische Klinik, Klinikum rechts der Isar, Technische Universität München, 81675, Munich, Germany
- Institut für Humangenetik, Klinikum rechts der Isar, Technische Universität München, 81675, Munich, Germany
| | - Anne von Thaden
- German Center for Neurodegenerative Diseases (DZNE) Munich, Feodor-Lynen-Straße 17, 81377, Munich, Germany
| | - Kristin Rentzsch
- German Center for Neurodegenerative Diseases (DZNE) Munich, Feodor-Lynen-Straße 17, 81377, Munich, Germany
| | - Stephanie May
- German Center for Neurodegenerative Diseases (DZNE) Munich, Feodor-Lynen-Straße 17, 81377, Munich, Germany
| | - Meike Michaelsen
- German Center for Neurodegenerative Diseases (DZNE) Munich, Feodor-Lynen-Straße 17, 81377, Munich, Germany
| | - Benjamin M Schwenk
- German Center for Neurodegenerative Diseases (DZNE) Munich, Feodor-Lynen-Straße 17, 81377, Munich, Germany
| | - Jing Tan
- Institut für Neurogenomik, Helmholtz Zentrum München, 85764, Munich, Germany
| | - Benedikt Schoser
- Department of Neurology, Friedrich-Baur-Institute, Klinikum der Ludwig-Maximilians-Universität München, Ziemssenstr. 1a, 80336, Munich, Germany
| | - Marianne Dieterich
- German Center for Neurodegenerative Diseases (DZNE) Munich, Feodor-Lynen-Straße 17, 81377, Munich, Germany
- Munich Cluster for System Neurology (SyNergy), Feodor-Lynen-Straße 17, 81377, Munich, Germany
- Department of Neurology, Friedrich-Baur-Institute, Klinikum der Ludwig-Maximilians-Universität München, Ziemssenstr. 1a, 80336, Munich, Germany
| | - Leonard Petrucelli
- Department of Neuroscience, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL, 32224, USA
| | - Sabine M Hölter
- German Mouse Clinic, Institute of Experimental Genetics, German Research Center for Environmental Health, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764, Neuherberg, Germany
- Institute of Developmental Genetics, German Research Center for Environmental Health, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764, Neuherberg, Germany
| | - Wolfgang Wurst
- German Center for Neurodegenerative Diseases (DZNE) Munich, Feodor-Lynen-Straße 17, 81377, Munich, Germany
- Munich Cluster for System Neurology (SyNergy), Feodor-Lynen-Straße 17, 81377, Munich, Germany
- Institute of Developmental Genetics, German Research Center for Environmental Health, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764, Neuherberg, Germany
- Chair of Developmental Genetics, Technische Universität München, Freising-Weihenstephan, Germany
| | - Helmut Fuchs
- German Mouse Clinic, Institute of Experimental Genetics, German Research Center for Environmental Health, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764, Neuherberg, Germany
| | - Valerie Gailus-Durner
- German Mouse Clinic, Institute of Experimental Genetics, German Research Center for Environmental Health, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764, Neuherberg, Germany
| | - Martin Hrabe de Angelis
- German Mouse Clinic, Institute of Experimental Genetics, German Research Center for Environmental Health, Helmholtz Zentrum München, Ingolstädter Landstrasse 1, 85764, Neuherberg, Germany
- Chair of Experimental Genetics, School of Life Science Weihenstephan, Technische Universität München, Alte Akademie 8, 85354, Freising, Germany
- German Center for Diabetes Research (DZD), Ingolstädter Landstr. 1, 85764, Neuherberg, Germany
| | - Thomas Klopstock
- German Center for Neurodegenerative Diseases (DZNE) Munich, Feodor-Lynen-Straße 17, 81377, Munich, Germany
- Munich Cluster for System Neurology (SyNergy), Feodor-Lynen-Straße 17, 81377, Munich, Germany
- Department of Neurology, Friedrich-Baur-Institute, Klinikum der Ludwig-Maximilians-Universität München, Ziemssenstr. 1a, 80336, Munich, Germany
| | - Thomas Arzberger
- German Center for Neurodegenerative Diseases (DZNE) Munich, Feodor-Lynen-Straße 17, 81377, Munich, Germany
- Munich Cluster for System Neurology (SyNergy), Feodor-Lynen-Straße 17, 81377, Munich, Germany
- Center for Neuopathology and Prion Research, Ludwig-Maximilians-University Munich, Feodor-Lynen-Straße 23, 81377, Munich, Germany
- Department of Psychiatry and Psychotherapy, Ludwig-Maximilians University Munich, Nußbaumstraße 7, 80336, Munich, Germany
| | - Dieter Edbauer
- German Center for Neurodegenerative Diseases (DZNE) Munich, Feodor-Lynen-Straße 17, 81377, Munich, Germany.
- Munich Cluster for System Neurology (SyNergy), Feodor-Lynen-Straße 17, 81377, Munich, Germany.
- Institute for Metabolic Biochemistry, Ludwig-Maximilians-University Munich, Feodor-Lynen-Straße 17, 81337, Munich, Germany.
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Actin Tyrosine-53-Phosphorylation in Neuronal Maturation and Synaptic Plasticity. J Neurosci 2017; 36:5299-313. [PMID: 27170127 DOI: 10.1523/jneurosci.2649-15.2016] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2015] [Accepted: 03/31/2016] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED Rapid reorganization and stabilization of the actin cytoskeleton in dendritic spines enables cellular processes underlying learning, such as long-term potentiation (LTP). Dendritic spines are enriched in exceptionally short and dynamic actin filaments, but the studies so far have not revealed the molecular mechanisms underlying the high actin dynamics in dendritic spines. Here, we show that actin in dendritic spines is dynamically phosphorylated at tyrosine-53 (Y53) in rat hippocampal and cortical neurons. Our findings show that actin phosphorylation increases the turnover rate of actin filaments and promotes the short-term dynamics of dendritic spines. During neuronal maturation, actin phosphorylation peaks at the first weeks of morphogenesis, when dendritic spines form, and the amount of Y53-phosphorylated actin decreases when spines mature and stabilize. Induction of LTP transiently increases the amount of phosphorylated actin and LTP induction is deficient in neurons expressing mutant actin that mimics phosphorylation. Actin phosphorylation provides a molecular mechanism to maintain the high actin dynamics in dendritic spines during neuronal development and to induce fast reorganization of the actin cytoskeleton in synaptic plasticity. In turn, dephosphorylation of actin is required for the stabilization of actin filaments that is necessary for proper dendritic spine maturation and LTP maintenance. SIGNIFICANCE STATEMENT Dendritic spines are small protrusions from neuronal dendrites where the postsynaptic components of most excitatory synapses reside. Precise control of dendritic spine morphology and density is critical for normal brain function. Accordingly, aberrant spine morphology is linked to many neurological diseases. The actin cytoskeleton is a structural element underlying the proper morphology of dendritic spines. Therefore, defects in the regulation of the actin cytoskeleton in neurons have been implicated in neurological diseases. Here, we revealed a novel mechanism for regulating neuronal actin cytoskeleton that explains the specific organization and dynamics of actin in spines. The better we understand the regulation of the dendritic spine morphology, the better we understand what goes wrong in neurological diseases.
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50
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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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