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Bayonés L, Guerra-Fernández MJ, Figueroa-Cares C, Gallo LI, Alfonso-Bueno S, Caspe O, Canal MP, Báez-Matus X, González-Jamett A, Cárdenas AM, Marengo FD. Dynamin-2 mutations linked to neonatal-onset centronuclear myopathy impair exocytosis and endocytosis in adrenal chromaffin cells. J Neurochem 2024; 168:3268-3283. [PMID: 39126680 DOI: 10.1111/jnc.16194] [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: 03/06/2024] [Revised: 06/28/2024] [Accepted: 07/17/2024] [Indexed: 08/12/2024]
Abstract
Dynamins are large GTPases whose primary function is not only to catalyze membrane scission during endocytosis but also to modulate other cellular processes, such as actin polymerization and vesicle trafficking. Recently, we reported that centronuclear myopathy associated dynamin-2 mutations, p.A618T, and p.S619L, impair Ca2+-induced exocytosis of the glucose transporter GLUT4 containing vesicles in immortalized human myoblasts. As exocytosis and endocytosis occur within rapid timescales, here we applied high-temporal resolution techniques, such as patch-clamp capacitance measurements and carbon-fiber amperometry to assess the effects of these mutations on these two cellular processes, using bovine chromaffin cells as a study model. We found that the expression of any of these dynamin-2 mutants inhibits a dynamin and F-actin-dependent form of fast endocytosis triggered by single action potential stimulus, as well as inhibits a slow compensatory endocytosis induced by 500 ms square depolarization. Both dynamin-2 mutants further reduced the exocytosis induced by 500 ms depolarizations, and the frequency of release events and the recruitment of neuropeptide Y (NPY)-labeled vesicles to the cell cortex after stimulation of nicotinic acetylcholine receptors with 1,1-dimethyl-4-phenyl piperazine iodide (DMPP). They also provoked a significant decrease in the Ca2+-induced formation of new actin filaments in permeabilized chromaffin cells. In summary, our results indicate that the centronuclear myopathy (CNM)-linked p.A618T and p.S619L mutations in dynamin-2 affect exocytosis and endocytosis, being the disruption of F-actin dynamics a possible explanation for these results. These impaired cellular processes might underlie the pathogenic mechanisms associated with these mutations.
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Affiliation(s)
- Lucas Bayonés
- Instituto de Fisiología, Biología Molecular y Neurociencias. CONICET. Departamento de Fisiología y Biología Molecular y Celular. Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires, Buenos Aires, Argentina
| | - María José Guerra-Fernández
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Cindel Figueroa-Cares
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Luciana I Gallo
- Instituto de Fisiología, Biología Molecular y Neurociencias. CONICET. Departamento de Fisiología y Biología Molecular y Celular. Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Samuel Alfonso-Bueno
- Instituto de Fisiología, Biología Molecular y Neurociencias. CONICET. Departamento de Fisiología y Biología Molecular y Celular. Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Octavio Caspe
- Instituto de Fisiología, Biología Molecular y Neurociencias. CONICET. Departamento de Fisiología y Biología Molecular y Celular. Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires, Buenos Aires, Argentina
| | - María Pilar Canal
- Instituto de Fisiología, Biología Molecular y Neurociencias. CONICET. Departamento de Fisiología y Biología Molecular y Celular. Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Ximena Báez-Matus
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Arlek González-Jamett
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
- Escuela de Química y Farmacia, Facultad de Farmacia, Universidad de Valparaíso, Valparaíso, Chile
- Centro para la Investigación Traslacional en Neurofarmacología, CitNe, Universidad de Valparaíso, Valparaiso, Chile
| | - Ana M Cárdenas
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Fernando D Marengo
- Instituto de Fisiología, Biología Molecular y Neurociencias. CONICET. Departamento de Fisiología y Biología Molecular y Celular. Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires, Buenos Aires, Argentina
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2
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Lun W, Yan Q, Guo X, Zhou M, Bai Y, He J, Cao H, Che Q, Guo J, Su Z. Mechanism of action of the bile acid receptor TGR5 in obesity. Acta Pharm Sin B 2024; 14:468-491. [PMID: 38322325 PMCID: PMC10840437 DOI: 10.1016/j.apsb.2023.11.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 09/17/2023] [Accepted: 10/24/2023] [Indexed: 02/08/2024] Open
Abstract
G protein-coupled receptors (GPCRs) are a large family of membrane protein receptors, and Takeda G protein-coupled receptor 5 (TGR5) is a member of this family. As a membrane receptor, TGR5 is widely distributed in different parts of the human body and plays a vital role in regulating metabolism, including the processes of energy consumption, weight loss and blood glucose homeostasis. Recent studies have shown that TGR5 plays an important role in glucose and lipid metabolism disorders such as fatty liver, obesity and diabetes. With the global obesity situation becoming more and more serious, a comprehensive explanation of the mechanism of TGR5 and filling the gaps in knowledge concerning clinical ligand drugs are urgently needed. In this review, we mainly explain the anti-obesity mechanism of TGR5 to promote the further study of this target, and show the electron microscope structure of TGR5 and review recent studies on TGR5 ligands to illustrate the specific binding between TGR5 receptor binding sites and ligands, which can effectively provide new ideas for ligand research and promote drug research.
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Affiliation(s)
- Weijun Lun
- Guangdong Engineering Research Center of Natural Products and New Drugs, Guangdong Provincial University Engineering Technology Research Center of Natural Products and Drugs, Guangdong Pharmaceutical University, Guangzhou 510006, China
- Guangdong Metabolic Disease Research Center of Integrated Chinese and Western Medicine, Key Laboratory of Glucolipid Metabolic Disorder, Ministry of Education of China, Guangdong TCM Key Laboratory for Metabolic Diseases, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Qihao Yan
- Guangdong Engineering Research Center of Natural Products and New Drugs, Guangdong Provincial University Engineering Technology Research Center of Natural Products and Drugs, Guangdong Pharmaceutical University, Guangzhou 510006, China
- Guangdong Metabolic Disease Research Center of Integrated Chinese and Western Medicine, Key Laboratory of Glucolipid Metabolic Disorder, Ministry of Education of China, Guangdong TCM Key Laboratory for Metabolic Diseases, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Xinghua Guo
- Guangdong Engineering Research Center of Natural Products and New Drugs, Guangdong Provincial University Engineering Technology Research Center of Natural Products and Drugs, Guangdong Pharmaceutical University, Guangzhou 510006, China
- Guangdong Metabolic Disease Research Center of Integrated Chinese and Western Medicine, Key Laboratory of Glucolipid Metabolic Disorder, Ministry of Education of China, Guangdong TCM Key Laboratory for Metabolic Diseases, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Minchuan Zhou
- Guangdong Engineering Research Center of Natural Products and New Drugs, Guangdong Provincial University Engineering Technology Research Center of Natural Products and Drugs, Guangdong Pharmaceutical University, Guangzhou 510006, China
- Guangdong Metabolic Disease Research Center of Integrated Chinese and Western Medicine, Key Laboratory of Glucolipid Metabolic Disorder, Ministry of Education of China, Guangdong TCM Key Laboratory for Metabolic Diseases, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Yan Bai
- School of Public Health, Guangdong Pharmaceutical University, Guangzhou 510310, China
| | - Jincan He
- School of Public Health, Guangdong Pharmaceutical University, Guangzhou 510310, China
| | - Hua Cao
- School of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Zhongshan 528458, China
| | - Qishi Che
- Guangzhou Rainhome Pharm & Tech Co., Ltd., Science City, Guangzhou 510663, China
| | - Jiao Guo
- Guangdong Metabolic Disease Research Center of Integrated Chinese and Western Medicine, Key Laboratory of Glucolipid Metabolic Disorder, Ministry of Education of China, Guangdong TCM Key Laboratory for Metabolic Diseases, Guangdong Pharmaceutical University, Guangzhou 510006, China
| | - Zhengquan Su
- Guangdong Engineering Research Center of Natural Products and New Drugs, Guangdong Provincial University Engineering Technology Research Center of Natural Products and Drugs, Guangdong Pharmaceutical University, Guangzhou 510006, China
- Guangdong Metabolic Disease Research Center of Integrated Chinese and Western Medicine, Key Laboratory of Glucolipid Metabolic Disorder, Ministry of Education of China, Guangdong TCM Key Laboratory for Metabolic Diseases, Guangdong Pharmaceutical University, Guangzhou 510006, China
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3
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Wallis TP, Jiang A, Young K, Hou H, Kudo K, McCann AJ, Durisic N, Joensuu M, Oelz D, Nguyen H, Gormal RS, Meunier FA. Super-resolved trajectory-derived nanoclustering analysis using spatiotemporal indexing. Nat Commun 2023; 14:3353. [PMID: 37291117 PMCID: PMC10250379 DOI: 10.1038/s41467-023-38866-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Accepted: 05/11/2023] [Indexed: 06/10/2023] Open
Abstract
Single-molecule localization microscopy techniques are emerging as vital tools to unravel the nanoscale world of living cells by understanding the spatiotemporal organization of protein clusters at the nanometer scale. Current analyses define spatial nanoclusters based on detections but neglect important temporal information such as cluster lifetime and recurrence in "hotspots" on the plasma membrane. Spatial indexing is widely used in video games to detect interactions between moving geometric objects. Here, we use the R-tree spatial indexing algorithm to determine the overlap of the bounding boxes of individual molecular trajectories to establish membership in nanoclusters. Extending the spatial indexing into the time dimension allows the resolution of spatial nanoclusters into multiple spatiotemporal clusters. Using spatiotemporal indexing, we found that syntaxin1a and Munc18-1 molecules transiently cluster in hotspots, offering insights into the dynamics of neuroexocytosis. Nanoscale spatiotemporal indexing clustering (NASTIC) has been implemented as a free and open-source Python graphic user interface.
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Affiliation(s)
- Tristan P Wallis
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia.
| | - Anmin Jiang
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Kyle Young
- School of Mathematics and Physics, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Huiyi Hou
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Kye Kudo
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Alex J McCann
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Nela Durisic
- Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Merja Joensuu
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Dietmar Oelz
- School of Mathematics and Physics, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Hien Nguyen
- School of Mathematics and Physics, The University of Queensland, Brisbane, QLD, 4072, Australia
| | - Rachel S Gormal
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia.
| | - Frédéric A Meunier
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia.
- School of Biomedical Sciences, The University of Queensland, Brisbane, QLD, 4072, Australia.
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Chang HF, Schirra C, Pattu V, Krause E, Becherer U. Lytic granule exocytosis at immune synapses: lessons from neuronal synapses. Front Immunol 2023; 14:1177670. [PMID: 37275872 PMCID: PMC10233144 DOI: 10.3389/fimmu.2023.1177670] [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: 03/01/2023] [Accepted: 05/09/2023] [Indexed: 06/07/2023] Open
Abstract
Regulated exocytosis is a central mechanism of cellular communication. It is not only the basis for neurotransmission and hormone release, but also plays an important role in the immune system for the release of cytokines and cytotoxic molecules. In cytotoxic T lymphocytes (CTLs), the formation of the immunological synapse is required for the delivery of the cytotoxic substances such as granzymes and perforin, which are stored in lytic granules and released via exocytosis. The molecular mechanisms of their fusion with the plasma membrane are only partially understood. In this review, we discuss the molecular players involved in the regulated exocytosis of CTL, highlighting the parallels and differences to neuronal synaptic transmission. Additionally, we examine the strengths and weaknesses of both systems to study exocytosis.
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5
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Lu Y, Zhang Y, Lian N, Li X. Membrane Dynamics Regulated by Cytoskeleton in Plant Immunity. Int J Mol Sci 2023; 24:ijms24076059. [PMID: 37047032 PMCID: PMC10094514 DOI: 10.3390/ijms24076059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 03/02/2023] [Accepted: 03/13/2023] [Indexed: 04/14/2023] Open
Abstract
The plasma membrane (PM), which is composed of a lipid layer implanted with proteins, has diverse functions in plant responses to environmental triggers. The heterogenous dynamics of lipids and proteins in the plasma membrane play important roles in regulating cellular activities with an intricate pathway that orchestrates reception, signal transduction and appropriate response in the plant immune system. In the process of the plasma membrane participating in defense responses, the cytoskeletal elements have important functions in a variety of ways, including regulation of protein and lipid dynamics as well as vesicle trafficking. In this review, we summarized how the plasma membrane contributed to plant immunity and focused on the dynamic process of cytoskeleton regulation of endocytosis and exocytosis and propose future research directions.
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Affiliation(s)
- Yuqing Lu
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
- Institute of Tree Development and Genome Editing, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
| | - Yuan Zhang
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
- Institute of Tree Development and Genome Editing, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
| | - Na Lian
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
- Institute of Tree Development and Genome Editing, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
| | - Xiaojuan Li
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
- Institute of Tree Development and Genome Editing, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
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6
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Riachy L, Ferrand T, Chasserot-Golaz S, Galas L, Alexandre S, Montero-Hadjadje M. Advanced Imaging Approaches to Reveal Molecular Mechanisms Governing Neuroendocrine Secretion. Neuroendocrinology 2023; 113:107-119. [PMID: 34915491 DOI: 10.1159/000521457] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 12/09/2021] [Indexed: 11/19/2022]
Abstract
Identification of the molecular mechanisms governing neuroendocrine secretion and resulting intercellular communication is one of the great challenges of cell biology to better understand organism physiology and neurosecretion disruption-related pathologies such as hypertension, neurodegenerative, or metabolic diseases. To visualize molecule distribution and dynamics at the nanoscale, many imaging approaches have been developed and are still emerging. In this review, we provide an overview of the pioneering studies using transmission electron microscopy, atomic force microscopy, total internal reflection microscopy, and super-resolution microscopy in neuroendocrine cells to visualize molecular mechanisms driving neurosecretion processes, including exocytosis and associated fusion pores, endocytosis and associated recycling vesicles, and protein-protein or protein-lipid interactions. Furthermore, the potential and the challenges of these different advanced imaging approaches for application in the study of neuroendocrine cell biology are discussed, aiming to guide researchers to select the best approach for their specific purpose around the crucial but not yet fully understood neurosecretion process.
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Affiliation(s)
- Lina Riachy
- Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Institut de Recherche et d'Innovation Biomédicale de Normandie, Normandie University, UNIROUEN, INSERM, U1239, Rouen, France
| | - Thomas Ferrand
- Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Institut de Recherche et d'Innovation Biomédicale de Normandie, Normandie University, UNIROUEN, INSERM, U1239, Rouen, France
| | - Sylvette Chasserot-Golaz
- Institut des Neurosciences Cellulaires et Intégratives, Centre National de la Recherche Scientifique, Strasbourg University, Strasbourg, France
| | - Ludovic Galas
- Normandie University, UNIROUEN, INSERM, PRIMACEN, Rouen, France
| | - Stéphane Alexandre
- Polymères, Biopolymères, Surfaces Laboratory, CNRS, Normandie University, UNIROUEN, UMR 6270, Rouen, France
| | - Maité Montero-Hadjadje
- Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Institut de Recherche et d'Innovation Biomédicale de Normandie, Normandie University, UNIROUEN, INSERM, U1239, Rouen, France
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7
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Villanueva J, Giménez-Molina Y, Gutiérrez LM. Confocal Microscopy Studies of F-Actin Cytoskeleton Distribution and Dynamics Using Fluorescent LifeAct Constructs in Bovine Adrenal Chromaffin Cells. Methods Mol Biol 2023; 2565:297-309. [PMID: 36205902 DOI: 10.1007/978-1-0716-2671-9_20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Cultured bovine chromaffin cells have been characterized as a successful model to study changes in the cytoskeleton during the secretory process. In this sense, the distribution and dynamics of the F-actin cytoskeleton can be studied by confocal microscopy using appropriate molecular tools such as LifeAct, a peptide that stains the structures of F-actin. In this work, we describe some methodological protocols making possible to study, under controlled stimulus conditions, the local dynamic changes of F-actin in the cortical zone and also to detect the simultaneous displacements of chromaffin granules and organelles in active zones.
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Affiliation(s)
- José Villanueva
- Instituto de Neurociencias, Centro Mixto CSIC-Universidad Miguel Hernández, Alicante, Spain.
| | - Yolanda Giménez-Molina
- Instituto de Neurociencias, Centro Mixto CSIC-Universidad Miguel Hernández, Alicante, Spain
| | - Luis M Gutiérrez
- Instituto de Neurociencias, Centro Mixto CSIC-Universidad Miguel Hernández, Alicante, Spain
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8
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Illuminating membrane structural dynamics of fusion and endocytosis with advanced light imaging techniques. Biochem Soc Trans 2022; 50:1157-1167. [PMID: 35960003 PMCID: PMC9444071 DOI: 10.1042/bst20210263] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 06/24/2022] [Accepted: 07/27/2022] [Indexed: 11/17/2022]
Abstract
Visualization of cellular dynamics using fluorescent light microscopy has become a reliable and indispensable source of experimental evidence for biological studies. Over the past two decades, the development of super-resolution microscopy platforms coupled with innovations in protein and molecule labeling led to significant biological findings that were previously unobservable due to the barrier of the diffraction limit. As a result, the ability to image the dynamics of cellular processes is vastly enhanced. These imaging tools are extremely useful in cellular physiology for the study of vesicle fusion and endocytosis. In this review, we will explore the power of stimulated emission depletion (STED) and confocal microscopy in combination with various labeling techniques in real-time observation of the membrane transformation of fusion and endocytosis, as well as their underlying mechanisms. We will review how STED and confocal imaging are used to reveal fusion and endocytic membrane transformation processes in live cells, including hemi-fusion; hemi-fission; hemi-to-full fusion; fusion pore opening, expansion, constriction and closure; shrinking or enlargement of the Ω-shape membrane structure after vesicle fusion; sequential compound fusion; and the sequential endocytic membrane transformation from flat- to O-shape via the intermediate Λ- and Ω-shape transition. We will also discuss how the recent development of imaging techniques would impact future studies in the field.
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9
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Cook S, Lenardo MJ, Freeman AF. HEM1 Actin Immunodysregulatory Disorder: Genotypes, Phenotypes, and Future Directions. J Clin Immunol 2022; 42:1583-1592. [DOI: 10.1007/s10875-022-01327-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 07/01/2022] [Indexed: 11/30/2022]
Abstract
AbstractCells of the innate and adaptive immune systems depend on proper actin dynamics to control cell behavior for effective immune responses. Dysregulated actin networks are known to play a pathogenic role in an increasing number of inborn errors of immunity. The WAVE regulatory complex (WRC) mediates branched actin polymerization, a process required for key cellular functions including migration, phagocytosis, vesicular transport, and immune synapse formation. Recent reports of pathogenic variants in NCKAP1L, a hematopoietically restricted gene encoding the HEM1 protein component of the WRC, defined a novel disease involving recurrent bacterial and viral infections, autoimmunity, and excessive inflammation (OMIM 141180). This review summarizes the diverse clinical presentations and immunological phenotypes observed in HEM1-deficient patients. In addition, we integrate the pathophysiological mechanisms described in current literature and highlight the outstanding questions for diagnosis and management of the HEM1 actin immunodysregulatory disorder.
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10
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Schenk EB, Meunier FA, Oelz DB. Spatial redistribution of neurosecretory vesicles upon stimulation accelerates their directed transport to the plasma membrane. PLoS One 2022; 17:e0264521. [PMID: 35294476 PMCID: PMC8926195 DOI: 10.1371/journal.pone.0264521] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 02/11/2022] [Indexed: 11/19/2022] Open
Abstract
Through the integration of results from an imaging analysis of intracellular trafficking of labelled neurosecretory vesicles in chromaffin cells, we develop a Markov state model to describe their transport and binding kinetics. Our simulation results indicate that a spatial redistribution of neurosecretory vesicles occurs upon secretagogue stimulation leading vesicles to the plasma membrane where they undergo fusion thereby releasing adrenaline and noradrenaline. Furthermore, we find that this redistribution alone can explain the observed up-regulation of vesicle transport upon stimulation and its directional bias towards the plasma membrane. Parameter fitting indicates that in the deeper compartment within the cell, vesicle transport is asymmetric and characterised by a bias towards the plasma membrane.
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Affiliation(s)
- Elaine B. Schenk
- School of Mathematics & Physics, The University of Queensland, Brisbane, Australia
| | - Frederic A. Meunier
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute (QBI), The University of Queensland, Brisbane, Australia
| | - Dietmar B. Oelz
- School of Mathematics & Physics, The University of Queensland, Brisbane, Australia
- * E-mail:
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Wu LG, Chan CY. Multiple Roles of Actin in Exo- and Endocytosis. Front Synaptic Neurosci 2022; 14:841704. [PMID: 35308832 PMCID: PMC8931529 DOI: 10.3389/fnsyn.2022.841704] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 02/11/2022] [Indexed: 11/20/2022] Open
Abstract
Cytoskeletal filamentous actin (F-actin) has long been considered a molecule that may regulate exo- and endocytosis. However, its exact roles remained elusive. Recent studies shed new light on many crucial roles of F-actin in regulating exo- and endocytosis. Here, this progress is reviewed from studies of secretory cells, particularly neurons and endocrine cells. These studies reveal that F-actin is involved in mediating all kinetically distinguishable forms of endocytosis, including ultrafast, fast, slow, bulk, and overshoot endocytosis, likely via membrane pit formation. F-actin promotes vesicle replenishment to the readily releasable pool most likely via active zone clearance, which may sustain synaptic transmission and overcome short-term depression of synaptic transmission during repetitive firing. By enhancing plasma membrane tension, F-actin promotes fusion pore expansion, vesicular content release, and a fusion mode called shrink fusion involving fusing vesicle shrinking. Not only F-actin, but also the F-actin assembly pathway, including ATP hydrolysis, N-WASH, and formin, are involved in mediating these roles of exo- and endocytosis. Neurological disorders, including spinocerebellar ataxia 13 caused by Kv3.3 channel mutation, may involve impairment of F-actin and its assembly pathway, leading in turn to impairment of exo- and endocytosis at synapses that may contribute to neurological disorders.
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Affiliation(s)
- Ling-Gang Wu
- National Institute of Neurological Disorders and Stroke, Bethesda, MD, United States
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Chen D, Yu W, Aitken L, Gunn-Moore F. Willin/FRMD6: A Multi-Functional Neuronal Protein Associated with Alzheimer's Disease. Cells 2021; 10:cells10113024. [PMID: 34831245 PMCID: PMC8616527 DOI: 10.3390/cells10113024] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/24/2021] [Accepted: 10/25/2021] [Indexed: 12/18/2022] Open
Abstract
The FERM domain-containing protein 6 (FRMD6), also known as Willin, is an upstream regulator of Hippo signaling that has recently been shown to modulate actin cytoskeleton dynamics and mechanical phenotype of neuronal cells through ERK signaling. Physiological functions of Willin/FRMD6 in the nervous system include neuronal differentiation, myelination, nerve injury repair, and vesicle exocytosis. The newly established neuronal role of Willin/FRMD6 is of particular interest given the mounting evidence suggesting a role for Willin/FRMD6 in Alzheimer's disease (AD), including a series of genome wide association studies that position Willin/FRMD6 as a novel AD risk gene. Here we describe recent findings regarding the role of Willin/FRMD6 in the nervous system and its actions in cellular perturbations related to the pathogenesis of AD.
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Yan X, Wang Y, Xu M, Dahhan DA, Liu C, Zhang Y, Lin J, Bednarek SY, Pan J. Cross-talk between clathrin-dependent post-Golgi trafficking and clathrin-mediated endocytosis in Arabidopsis root cells. THE PLANT CELL 2021; 33:3057-3075. [PMID: 34240193 PMCID: PMC8462817 DOI: 10.1093/plcell/koab180] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 06/30/2021] [Indexed: 05/26/2023]
Abstract
Coupling of post-Golgi and endocytic membrane transport ensures that the flow of materials to/from the plasma membrane (PM) is properly balanced. The mechanisms underlying the coordinated trafficking of PM proteins in plants, however, are not well understood. In plant cells, clathrin and its adaptor protein complexes, AP-2 and the TPLATE complex (TPC) at the PM, and AP-1 at the trans-Golgi network/early endosome (TGN/EE), function in clathrin-mediated endocytosis (CME) and post-Golgi trafficking. Here, we utilized mutants with defects in clathrin-dependent post-Golgi trafficking and CME, in combination with other cytological and pharmacological approaches, to further investigate the machinery behind the coordination of protein delivery and recycling to/from the TGN/EE and PM in Arabidopsis (Arabidopsis thaliana) root cells. In mutants with defective AP-2-/TPC-dependent CME, we determined that clathrin and AP-1 recruitment to the TGN/EE as well as exocytosis are significantly impaired. Likewise, defects in AP-1-dependent post-Golgi trafficking and pharmacological inhibition of exocytosis resulted in the reduced association of clathrin and AP-2/TPC subunits with the PM and a reduction in the internalization of cargoes via CME. Together, these results suggest that post-Golgi trafficking and CME are coupled via modulation of clathrin and adaptor protein complex recruitment to the TGN/EE and PM.
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Affiliation(s)
- Xu Yan
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Yutong Wang
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Mei Xu
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Dana A. Dahhan
- Department of Biochemistry, University of Wisconsin–Madison, Madison, Wisconsin 53706
| | - Chan Liu
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
| | - Yan Zhang
- State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai’an 271018, China
| | - Jinxing Lin
- College of Biological Sciences and Biotechnology, Beijing Forestry University, Beijing 100083, China
| | - Sebastian Y. Bednarek
- Department of Biochemistry, University of Wisconsin–Madison, Madison, Wisconsin 53706
| | - Jianwei Pan
- Ministry of Education Key Laboratory of Cell Activities and Stress Adaptations, School of Life Sciences, Lanzhou University, Lanzhou 730000, China
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14
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Perino A, Velázquez-Villegas LA, Bresciani N, Sun Y, Huang Q, Fénelon VS, Castellanos-Jankiewicz A, Zizzari P, Bruschetta G, Jin S, Baleisyte A, Gioiello A, Pellicciari R, Ivanisevic J, Schneider BL, Diano S, Cota D, Schoonjans K. Central anorexigenic actions of bile acids are mediated by TGR5. Nat Metab 2021; 3:595-603. [PMID: 34031591 PMCID: PMC7610881 DOI: 10.1038/s42255-021-00398-4] [Citation(s) in RCA: 73] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2020] [Accepted: 04/26/2021] [Indexed: 12/21/2022]
Abstract
Bile acids (BAs) are signalling molecules that mediate various cellular responses in both physiological and pathological processes. Several studies report that BAs can be detected in the brain1, yet their physiological role in the central nervous system is still largely unknown. Here we show that postprandial BAs can reach the brain and activate a negative-feedback loop controlling satiety in response to physiological feeding via TGR5, a G-protein-coupled receptor activated by multiple conjugated and unconjugated BAs2 and an established regulator of peripheral metabolism3-8. Notably, peripheral or central administration of a BA mix or a TGR5-specific BA mimetic (INT-777) exerted an anorexigenic effect in wild-type mice, while whole-body, neuron-specific or agouti-related peptide neuronal TGR5 deletion caused a significant increase in food intake. Accordingly, orexigenic peptide expression and secretion were reduced after short-term TGR5 activation. In vitro studies demonstrated that activation of the Rho-ROCK-actin-remodelling pathway decreases orexigenic agouti-related peptide/neuropeptide Y (AgRP/NPY) release in a TGR5-dependent manner. Taken together, these data identify a signalling cascade by which BAs exert acute effects at the transition between fasting and feeding and prime the switch towards satiety, unveiling a previously unrecognized role of physiological feedback mediated by BAs in the central nervous system.
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Affiliation(s)
- Alessia Perino
- Institute of Bioengineering, Faculty of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Laura A Velázquez-Villegas
- Institute of Bioengineering, Faculty of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
- Departamento de Fisiología de la Nutrición, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, México D.F., Mexico
| | - Nadia Bresciani
- Institute of Bioengineering, Faculty of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Yu Sun
- Institute of Bioengineering, Faculty of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Qingyao Huang
- Institute of Bioengineering, Faculty of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Valérie S Fénelon
- University of Bordeaux, INSERM, Neurocentre Magendie, U1215, F-3300, Bordeaux, France
| | | | - Philippe Zizzari
- University of Bordeaux, INSERM, Neurocentre Magendie, U1215, F-3300, Bordeaux, France
| | - Giuseppe Bruschetta
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT, USA
| | - Sungho Jin
- Department of Molecular Pharmacology and Therapeutics, Columbia University Irving Medical Center, New York, NY, USA
| | - Aiste Baleisyte
- Brain Mind Institute, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Antimo Gioiello
- Department of Pharmaceutical Sciences, University of Perugia, Perugia, Italy
| | | | - Julijana Ivanisevic
- Metabolomics Platform, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Switzerland
| | - Bernard L Schneider
- Bertarelli Platform for Gene Therapy, Ecole Polytechnique Fédérale de Lausanne, Geneva, Switzerland
| | - Sabrina Diano
- Department of Cellular and Molecular Physiology, Yale University School of Medicine, New Haven, CT, USA
- Department of Molecular Pharmacology and Therapeutics, Columbia University Irving Medical Center, New York, NY, USA
| | - Daniela Cota
- University of Bordeaux, INSERM, Neurocentre Magendie, U1215, F-3300, Bordeaux, France
| | - Kristina Schoonjans
- Institute of Bioengineering, Faculty of Life Sciences, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
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15
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Chenouard N, Xuan F, Tsien RW. Synaptic vesicle traffic is supported by transient actin filaments and regulated by PKA and NO. Nat Commun 2020; 11:5318. [PMID: 33087709 PMCID: PMC7578807 DOI: 10.1038/s41467-020-19120-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 09/25/2020] [Indexed: 11/10/2022] Open
Abstract
Synaptic vesicles (SVs) can be pooled across multiple synapses, prompting questions about their dynamic allocation for neurotransmission and plasticity. We find that the axonal traffic of recycling vesicles is not supported by ubiquitous microtubule-based motility but relies on actin instead. Vesicles freed from synaptic clusters undergo ~1 µm bouts of active transport, initiated by nearby elongation of actin filaments. Long distance translocation arises when successive bouts of active transport were linked by periods of free diffusion. The availability of SVs for active transport can be promptly increased by protein kinase A, a key player in neuromodulation. Vesicle motion is in turn impeded by shutting off axonal actin polymerization, mediated by nitric oxide-cyclic GMP signaling leading to inhibition of RhoA. These findings provide a potential framework for coordinating post-and pre-synaptic strength, using retrograde regulation of axonal actin dynamics to mobilize and recruit presynaptic SV resources.
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Affiliation(s)
- Nicolas Chenouard
- NYU Neuroscience Institute and Department of Neuroscience and Physiology, NYU Langone Medical Center, New York, NY, 10016, USA.,Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, F-33000, Bordeaux, France
| | - Feng Xuan
- NYU Neuroscience Institute and Department of Neuroscience and Physiology, NYU Langone Medical Center, New York, NY, 10016, USA.,Interdepartmental Neuroscience Program, Northwestern University, Evanston, IL, 60208, USA
| | - Richard W Tsien
- NYU Neuroscience Institute and Department of Neuroscience and Physiology, NYU Langone Medical Center, New York, NY, 10016, USA. .,Center for Neural Science, New York University, New York, NY, 10003, USA.
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16
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Liebman C, McColloch A, Rabiei M, Bowling A, Cho M. Mechanics of the cell: Interaction mechanisms and mechanobiological models. CURRENT TOPICS IN MEMBRANES 2020; 86:143-184. [PMID: 33837692 DOI: 10.1016/bs.ctm.2020.09.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The importance of cell mechanics has long been recognized for the cell development and function. Biomechanics plays an important role in cell metabolism, regulation of mechanotransduction pathways and also modulation of nuclear response. The mechanical properties of the cell are likely determined by, among many others, the cytoskeleton elasticity, membrane tension and cell-substrate adhesion. This coordinated but complex mechanical interplay is required however, for the cell to respond to and influence in a reciprocal manner the chemical and mechanical signals from the extracellular matrix (ECM). In an effort to better and more fully understand the cell mechanics, the role of nuclear mechanics has emerged as an important contributor to the overall cellular mechanics. It is not too difficult to appreciate the physical connection between the nucleus and the cytoskeleton network that may be connected to the ECM through the cell membrane. Transmission of forces from ECM through this connection is essential for a wide range of cellular behaviors and functions such as cytoskeletal reorganization, nuclear movement, cell migration and differentiation. Unlike the cellular mechanics that can be measured using a number of biophysical techniques that were developed in the past few decades, it still remains a daunting challenge to probe the nuclear mechanics directly. In this paper, we therefore aim to provide informative description of the cell membrane and cytoskeleton mechanics, followed by unique computational modeling efforts to elucidate the nucleus-cytoskeleton coupling. Advances in our knowledge of complete cellular biomechanics and mechanotransduction may lead to clinical relevance and applications in mechano-diseases such as atherosclerosis, stem cell-based therapies, and the development of tissue engineered products.
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Affiliation(s)
- Caleb Liebman
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, United States
| | - Andrew McColloch
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, United States
| | - Manoochehr Rabiei
- Department of Mechanical and Aerospace Engineering, University of Texas at Arlington, Arlington, TX, United States
| | - Alan Bowling
- Department of Mechanical and Aerospace Engineering, University of Texas at Arlington, Arlington, TX, United States.
| | - Michael Cho
- Department of Bioengineering, University of Texas at Arlington, Arlington, TX, United States.
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17
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Tong Z, Liu Y, Xia R, Chang Y, Hu Y, Liu P, Zhai Z, Zhang J, Li H. F-actin Regulates Osteoblastic Differentiation of Mesenchymal Stem Cells on TiO 2 Nanotubes Through MKL1 and YAP/TAZ. NANOSCALE RESEARCH LETTERS 2020; 15:183. [PMID: 32965618 PMCID: PMC7511505 DOI: 10.1186/s11671-020-03415-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 09/14/2020] [Indexed: 05/02/2023]
Abstract
Titanium and titanium alloys are widely used in orthopedic implants. Modifying the nanotopography provides a new strategy to improve osseointegration of titanium substrates. Filamentous actin (F-actin) polymerization, as a mechanical loading structure, is generally considered to be involved in cell migration, endocytosis, cell division, and cell shape maintenance. Whether F-actin is involved and how it functions in nanotube-induced osteogenic differentiation of mesenchymal stem cells (MSCs) remain to be elucidated. In this study, we fabricated TiO2 nanotubes on the surface of a titanium substrate by anodic oxidation and characterized their features by scanning electron microscopy (SEM), X-ray energy dispersive analysis (EDS), and atomic force microscopy (AFM). Alkaline phosphatase (ALP) staining, Western blotting, qRT-PCR, and immunofluorescence staining were performed to explore the osteogenic potential, the level of F-actin, and the expression of MKL1 and YAP/TAZ. Our results showed that the inner diameter and roughness of TiO2 nanotubes increased with the increase of the anodic oxidation voltage from 30 to 70 V, while their height was 2 μm consistently. Further, the larger the tube diameter, the stronger the ability of TiO2 nanotubes to promote osteogenic differentiation of MSCs. Inhibiting F-actin polymerization by Cyto D inhibited osteogenic differentiation of MSCs as well as the expression of proteins contained in focal adhesion complexes such as vinculin (VCL) and focal adhesion kinase (FAK). In contrast, after Jasp treatment, polymerization of F-actin enhanced the expression of RhoA and transcription factors YAP/TAZ. Based on these data, we concluded that TiO2 nanotubes facilitated the osteogenic differentiation of MSCs, and this ability was enhanced with the increasing diameter of the nanotubes within a certain range (30-70 V). F-actin mediated this process through MKL1 and YAP/TAZ.
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Affiliation(s)
- Zhicheng Tong
- Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, People's Republic of China
| | - Yanchang Liu
- Department of Orthopedics, The Second Hospital of Anhui Medical University, Hefei, 230601, Anhui, People's Republic of China
| | - Runzhi Xia
- Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, People's Republic of China
| | - Yongyun Chang
- Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, People's Republic of China
| | - Yi Hu
- Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, People's Republic of China
| | - Pengcheng Liu
- Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, People's Republic of China
| | - Zanjing Zhai
- Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, People's Republic of China
| | - Jingwei Zhang
- Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, People's Republic of China
| | - Huiwu Li
- Shanghai Key Laboratory of Orthopaedic Implants, Department of Orthopaedic Surgery, Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, 200011, People's Republic of China.
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18
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Beck J, Kressel M. FERM domain-containing protein 6 identifies a subpopulation of varicose nerve fibers in different vertebrate species. Cell Tissue Res 2020; 381:13-24. [PMID: 32200438 PMCID: PMC7306050 DOI: 10.1007/s00441-020-03189-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 02/16/2020] [Indexed: 12/29/2022]
Abstract
FERM domain-containing protein 6 (FRMD6) is a member of the FERM protein superfamily, which is evolutionary highly conserved and has recently been identified as an upstream regulator of the conserved growth-promoting Hippo signaling pathway. In clinical studies, the FRMD6 gene is correlated with high significance to Alzheimer's disease and cognitive impairment implicating a wider role of this protein in the nervous system. Scare data are available on the localization of endogenous FRMD6 in neural tissues. Using a FRMD6-directed antiserum, we detected specific immunoreactivity in varicose nerve fibers in the rat central and peripheral nervous system. FRMD6-immunoreactive (-ir) neurons were found in the sensory ganglia of cranial nerves, which were marked by a pool of labeled cytoplasmic granules. Cross-species comparative studies detected a morphologically identical fiber population and a comparable fiber distribution in tissues from xenopus and human cranial nerves and ganglia. In the spinal cord, FRMD6-ir was detectable in the terminal endings of primary afferent neurons containing substance P (SP). In the rat diencephalon, FRMD6-ir was co-localized with either SP- or arginine vasopressin-positive fibers in Broca's diagonal band and the lateral septum. Dense fiber terminals containing both FRMD6-ir and growth hormone-releasing hormone were found in the median eminence. The intimate association of FRMD6 with secretory vesicles was investigated in vitro. Induction of exocytotic vesicles in cultured cells by ectopic expression of the SP precursor molecule preprotachykinin A led to a redistribution and co-localization of endogenous FRMD6 with secretory granules closely mimicking the observations in tissues.
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Affiliation(s)
- Josefa Beck
- Institute of Anatomy and Cell Biology, University of Erlangen, Krankenhausstr. 9, 91054, Erlangen, Germany
| | - Michael Kressel
- Institute of Anatomy and Cell Biology, University of Erlangen, Krankenhausstr. 9, 91054, Erlangen, Germany.
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19
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Miklavc P, Frick M. Actin and Myosin in Non-Neuronal Exocytosis. Cells 2020; 9:cells9061455. [PMID: 32545391 PMCID: PMC7348895 DOI: 10.3390/cells9061455] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Revised: 06/03/2020] [Accepted: 06/06/2020] [Indexed: 12/18/2022] Open
Abstract
Cellular secretion depends on exocytosis of secretory vesicles and discharge of vesicle contents. Actin and myosin are essential for pre-fusion and post-fusion stages of exocytosis. Secretory vesicles depend on actin for transport to and attachment at the cell cortex during the pre-fusion phase. Actin coats on fused vesicles contribute to stabilization of large vesicles, active vesicle contraction and/or retrieval of excess membrane during the post-fusion phase. Myosin molecular motors complement the role of actin. Myosin V is required for vesicle trafficking and attachment to cortical actin. Myosin I and II members engage in local remodeling of cortical actin to allow vesicles to get access to the plasma membrane for membrane fusion. Myosins stabilize open fusion pores and contribute to anchoring and contraction of actin coats to facilitate vesicle content release. Actin and myosin function in secretion is regulated by a plethora of interacting regulatory lipids and proteins. Some of these processes have been first described in non-neuronal cells and reflect adaptations to exocytosis of large secretory vesicles and/or secretion of bulky vesicle cargoes. Here we collate the current knowledge and highlight the role of actomyosin during distinct phases of exocytosis in an attempt to identify unifying molecular mechanisms in non-neuronal secretory cells.
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Affiliation(s)
- Pika Miklavc
- School of Science, Engineering & Environment, University of Salford, Manchester M5 4WT, UK
- Correspondence: (P.M.); (M.F.); Tel.: +44-0161-295-3395 (P.M.); +49-731-500-23115 (M.F.); Fax: +49-731-500-23242 (M.F.)
| | - Manfred Frick
- Institute of General Physiology, Ulm University, Albert-Einstein-Allee 11, 89081 Ulm, Germany
- Correspondence: (P.M.); (M.F.); Tel.: +44-0161-295-3395 (P.M.); +49-731-500-23115 (M.F.); Fax: +49-731-500-23242 (M.F.)
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20
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Glomb O, Wu Y, Rieger L, Rüthnick D, Mulaw MA, Johnsson N. The cell polarity proteins Boi1 and Boi2 direct an actin nucleation complex to sites of exocytosis in Saccharomyces cerevisiae. J Cell Sci 2020; 133:jcs.237982. [PMID: 31964708 DOI: 10.1242/jcs.237982] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 12/19/2019] [Indexed: 01/13/2023] Open
Abstract
Owing to the local enrichment of factors that influence its dynamics and organization, the actin cytoskeleton displays different shapes and functions within the same cell. In yeast cells, post-Golgi vesicles ride on long actin cables to the bud tip. The proteins Boi1 and Boi2 (Boi1/2) participate in tethering and docking these vesicles to the plasma membrane. Here, we show in Saccharomyces cerevisiae that Boi1/2 also recruit nucleation and elongation factors to form actin filaments at sites of exocytosis. Disrupting the connection between Boi1/2 and the nucleation factor Bud6 impairs filament formation, reduces the directed movement of the vesicles to the tip and shortens the vesicles' tethering time at the cortex. Transplanting Boi1 from the bud tip to the peroxisomal membrane partially redirects the actin cytoskeleton and the vesicular flow towards the peroxisome, and creates an alternative, rudimentary vesicle-docking zone. We conclude that Boi1/2, through interactions with Bud6 and Bni1, induce the formation of a cortical actin structure that receives and aligns incoming vesicles before fusion with the membrane.
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Affiliation(s)
- Oliver Glomb
- Institute of Molecular Genetics and Cell Biology, Department of Biology, Ulm University, James-Franck-Ring N27, D-89081 Ulm, Germany
| | - Yehui Wu
- Institute of Molecular Genetics and Cell Biology, Department of Biology, Ulm University, James-Franck-Ring N27, D-89081 Ulm, Germany
| | - Lucia Rieger
- Institute of Molecular Genetics and Cell Biology, Department of Biology, Ulm University, James-Franck-Ring N27, D-89081 Ulm, Germany
| | - Diana Rüthnick
- ZMBH, University of Heidelberg, Im Neuenheimer Feld 282, D-69120 Heidelberg, Germany
| | - Medhanie A Mulaw
- Comprehensive Cancer Center Ulm, Institute of Experimental Cancer Research, Ulm University, James-Franck-Ring N27, D-89081 Ulm, Germany
| | - Nils Johnsson
- Institute of Molecular Genetics and Cell Biology, Department of Biology, Ulm University, James-Franck-Ring N27, D-89081 Ulm, Germany
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21
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Wosik J, Suarez-Villagran M, Miller JH, Ghobrial RM, Kloc M. Macrophage phenotype bioengineered by magnetic, genetic, or pharmacologic interference. Immunol Res 2019; 67:1-11. [PMID: 30649660 DOI: 10.1007/s12026-019-9066-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
In all eukaryotes, the cell shape depends on the actin filament cytoskeleton, which is regulated by the small GTPase RhoA. It is well known that the cell shape determines cell function and behavior. Inversely, any change in the cell behavior and/or function reverberates at the cell shape. In this review, we describe how mechanical/magnetic, genetic, or pharmacologic interference with the actin cytoskeleton enforces changes in cell shape and function and how such techniques can be used to control the phenotype and functions of immune cells such as macrophages and to develop novel anti-cancer and anti-rejection clinical therapies.
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Affiliation(s)
- Jarek Wosik
- Electrical and Computer Engineering Department, University of Houston, Houston, TX, 77204, USA. .,Texas Center for Superconductivity, University of Houston, HSC Bldg., Rm. 202, Houston, TX, 77204-5002, USA.
| | - Martha Suarez-Villagran
- Electrical and Computer Engineering Department, University of Houston, Houston, TX, 77204, USA.,Physics Department, University of Houston, Houston, TX, USA
| | - John H Miller
- Electrical and Computer Engineering Department, University of Houston, Houston, TX, 77204, USA.,Physics Department, University of Houston, Houston, TX, USA
| | - Rafik M Ghobrial
- The Houston Methodist Research Institute, Houston, TX, 77030, USA.,Department of Surgery, The Houston Methodist Hospital, 6550 Fannin St., Houston, TX, 77030, USA
| | - Malgorzata Kloc
- The Houston Methodist Research Institute, Houston, TX, 77030, USA. .,Department of Surgery, The Houston Methodist Hospital, 6550 Fannin St., Houston, TX, 77030, USA. .,M.D. Anderson Cancer Center, Department of Genetics, The University of Texas, Houston, TX, 77030, USA.
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22
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Jung W, Tabatabai AP, Thomas JJ, Tabei SMA, Murrell MP, Kim T. Dynamic motions of molecular motors in the actin cytoskeleton. Cytoskeleton (Hoboken) 2019; 76:517-531. [PMID: 31758841 DOI: 10.1002/cm.21582] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 11/14/2019] [Accepted: 11/19/2019] [Indexed: 12/23/2022]
Abstract
During intracellular transport, cellular cargos, such as organelles, vesicles, and proteins, are transported within cells. Intracellular transport plays an important role in diverse cellular functions. Molecular motors walking on the cytoskeleton facilitate active intracellular transport, which is more efficient than diffusion-based passive transport. Active transport driven by kinesin and dynein walking on microtubules has been studied well during recent decades. However, mechanisms of active transport occurring in disorganized actin networks via myosin motors remain elusive. To provide physiologically relevant insights, we probed motions of myosin motors in actin networks under various conditions using our well-established computational model that rigorously accounts for the mechanical and dynamical behaviors of the actin cytoskeleton. We demonstrated that myosin motions can be confined due to three different reasons in the absence of F-actin turnover. We verified mechanisms of motor stalling using in vitro reconstituted actomyosin networks. We also found that with F-actin turnover, motors consistently move for a long time without significant confinement. Our study sheds light on the importance of F-actin turnover for effective active transport in the actin cytoskeleton.
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Affiliation(s)
- Wonyeong Jung
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, Indiana
| | - A Pasha Tabatabai
- Systems Biology Institute, Yale University, 850 West Campus Drive, West Haven, Connecticut.,Department of Biomedical Engineering, Yale University, 55 Prospect Street, New Haven, Connecticut
| | - Jacob J Thomas
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, Indiana
| | - S M Ali Tabei
- Department of Physics, University of Northern Iowa, 215 Begeman Hall, Cedar Falls, Iowa
| | - Michael P Murrell
- Systems Biology Institute, Yale University, 850 West Campus Drive, West Haven, Connecticut.,Department of Biomedical Engineering, Yale University, 55 Prospect Street, New Haven, Connecticut.,Department of Physics, Yale University. 217 Prospect Street, New Haven, Connecticut
| | - Taeyoon Kim
- Weldon School of Biomedical Engineering, Purdue University, 206 S. Martin Jischke Drive, West Lafayette, Indiana
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23
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Abstract
Synaptotagmin 1 (Syt1) is an abundant and important presynaptic vesicle protein that binds Ca2+ for the regulation of synaptic vesicle exocytosis. Our previous study reported its localization and function on spindle assembly in mouse oocyte meiotic maturation. The present study was designed to investigate the function of Syt1 during mouse oocyte activation and subsequent cortical granule exocytosis (CGE) using confocal microscopy, morpholinol-based knockdown and time-lapse live cell imaging. By employing live cell imaging, we first studied the dynamic process of CGE and calculated the time interval between [Ca2+]i rise and CGE after oocyte activation. We further showed that Syt1 was co-localized to cortical granules (CGs) at the oocyte cortex. After oocyte activation with SrCl2, the Syt1 distribution pattern was altered significantly, similar to the changes seen for the CGs. Knockdown of Syt1 inhibited [Ca2+]i oscillations, disrupted the F-actin distribution pattern and delayed the time of cortical reaction. In summary, as a synaptic vesicle protein and calcium sensor for exocytosis, Syt1 acts as an essential regulator in mouse oocyte activation events including the generation of Ca2+ signals and CGE.
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Pons-Vizcarra M, Kurps J, Tawfik B, Sørensen JB, van Weering JRT, Verhage M. MUNC18-1 regulates the submembrane F-actin network, independently of syntaxin1 targeting, via hydrophobicity in β-sheet 10. J Cell Sci 2019; 132:jcs.234674. [PMID: 31719162 DOI: 10.1242/jcs.234674] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 11/01/2019] [Indexed: 01/08/2023] Open
Abstract
MUNC18-1 (also known as STXBP1) is an essential protein for docking and fusion of secretory vesicles. Mouse chromaffin cells (MCCs) lacking MUNC18-1 show impaired secretory vesicle docking, but also mistargeting of SNARE protein syntaxin1 and an abnormally dense submembrane F-actin network. Here, we tested the contribution of both these phenomena to docking and secretion defects in MUNC18-1-deficient MCCs. We show that an abnormal F-actin network and syntaxin1 targeting defects are not observed in Snap25- or Syt1-knockout (KO) MCCs, which are also secretion deficient. We identified a MUNC18-1 mutant (V263T in β-sheet 10) that fully restores syntaxin1 targeting but not F-actin abnormalities in Munc18-1-KO cells. MUNC18-2 and -3 (also known as STXBP2 and STXBP3, respectively), which lack the hydrophobic residue at position 263, also did not restore a normal F-actin network in Munc18-1-KO cells. However, these proteins did restore the normal F-actin network when a hydrophobic residue was introduced at the corresponding position. Munc18-1-KO MCCs expressing MUNC18-1(V263T) showed normal vesicle docking and exocytosis. These results demonstrate that MUNC18-1 regulates the F-actin network independently of syntaxin1 targeting via hydrophobicity in β-sheet 10. The abnormally dense F-actin network in Munc18-1-deficient cells is not a rate-limiting barrier in secretory vesicle docking or fusion.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Maria Pons-Vizcarra
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, Vrije Universiteit Amsterdam, de Boelelaan 1085, Amsterdam 1081 HV, The Netherlands
| | - Julia Kurps
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, Vrije Universiteit Amsterdam, de Boelelaan 1085, Amsterdam 1081 HV, The Netherlands
| | - Bassam Tawfik
- Neurosecretion group, Signaling Laboratory, Department of Neuroscience and Pharmacology, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Jakob B Sørensen
- Neurosecretion group, Signaling Laboratory, Department of Neuroscience and Pharmacology, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Jan R T van Weering
- Department of Clinical Genetics, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, Amsterdam UMC, location VUmc, de Boelelaan 1085, Amsterdam 1081 HV, The Netherlands
| | - Matthijs Verhage
- Department of Functional Genomics, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, Vrije Universiteit Amsterdam, de Boelelaan 1085, Amsterdam 1081 HV, The Netherlands .,Department of Clinical Genetics, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam, Amsterdam UMC, location VUmc, de Boelelaan 1085, Amsterdam 1081 HV, The Netherlands
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25
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Gómez-Elías MD, Fissore RA, Cuasnicú PS, Cohen DJ. Compensatory endocytosis occurs after cortical granule exocytosis in mouse eggs. J Cell Physiol 2019; 235:4351-4360. [PMID: 31612508 DOI: 10.1002/jcp.29311] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 09/30/2019] [Indexed: 12/31/2022]
Abstract
Compensatory endocytosis (CE) is one of the primary mechanisms through which cells maintain their surface area after exocytosis. Considering that in eggs massive exocytosis of cortical granules (CG) takes place after fertilization, the aim of this study was to evaluate the occurrence of CE following cortical exocytosis in mouse eggs. For this purpose, we developed a pulse-chase assay to detect CG membrane internalization. Results showed internalized labeling in SrCl2 -activated and fertilized eggs when chasing at 37°C, but not at a nonpermissive temperature (4°C). The use of kinase and calcineurin inhibitors led us to conclude that this internal labeling corresponded to CE. Further experiments showed that CE in mouse eggs is dependent on actin dynamics and dynamin activity, and could be associated with a transient exposure of phosphatidylserine. Finally, CE was impaired in A23187 ionophore-activated eggs, highlighting once again the mechanistic differences between the activation methods. Altogether, these results demonstrate for the first time that egg activation triggers CE in mouse eggs after exocytosis of CG, probably as a plasma membrane homeostasis mechanism.
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Affiliation(s)
- Matías D Gómez-Elías
- Laboratorio de Mecanismos Moleculares de la Fertilización, Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científico y Técnicas (IBYME-CONICET), Buenos Aires, Argentina
| | - Rafael A Fissore
- Department of Veterinary and Animal Sciences, University of Massachusetts Amherst, 661 North Pleasant Street, Amherst, Massachusetts
| | - Patricia S Cuasnicú
- Laboratorio de Mecanismos Moleculares de la Fertilización, Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científico y Técnicas (IBYME-CONICET), Buenos Aires, Argentina
| | - Débora J Cohen
- Laboratorio de Mecanismos Moleculares de la Fertilización, Instituto de Biología y Medicina Experimental, Consejo Nacional de Investigaciones Científico y Técnicas (IBYME-CONICET), Buenos Aires, Argentina
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26
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Deng H, Dutta P, Liu J. Stochastic modeling of nanoparticle internalization and expulsion through receptor-mediated transcytosis. NANOSCALE 2019; 11:11227-11235. [PMID: 31157808 PMCID: PMC6634982 DOI: 10.1039/c9nr02710f] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Receptor-mediated transcytosis (RMT) is a fundamental mechanism for the transcellular transport of nanoparticles. RMT is a complex process, during which the nanoparticles actively interact with the membrane and the membrane profile undergoes extreme deformations for particle internalization and expulsion. In this work, we developed a stochastic model to study the endocytosis and exocytosis of nanoparticles across soft membranes. The model is based on the combination of a stochastic particle binding model with a membrane model, and accounts for both clathrin-mediated endocytosis for internalization and actin-mediated exocytosis for expulsion. Our results showed that nanoparticles must have certain avidity with enough ligand density and ligand-receptor binding affinity to be taken up, while too high avidity limited the particle release from the cell surface. We further explored the functional roles of actin during exocytosis, which has been a topic under active debate. Our simulations indicated that the membrane compression due to the actin induced tension tended to break the ligand-receptor bonds and to shrink the fusion pore. Therefore, an intermediate tension promoted the fusion pore expansion and nanoparticle release, while high tension prohibits particle release. Our model provides new and critical mechanistic insights into RMT, and represents a powerful platform for aiding the rational design of nanocarriers for controlled drug delivery.
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Affiliation(s)
- Hua Deng
- School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99163, USA.
| | - Prashanta Dutta
- School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99163, USA.
| | - Jin Liu
- School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99163, USA.
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Leptin-induced Trafficking of K ATP Channels: A Mechanism to Regulate Pancreatic β-cell Excitability and Insulin Secretion. Int J Mol Sci 2019; 20:ijms20112660. [PMID: 31151172 PMCID: PMC6600549 DOI: 10.3390/ijms20112660] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2019] [Revised: 05/25/2019] [Accepted: 05/27/2019] [Indexed: 11/17/2022] Open
Abstract
The adipocyte hormone leptin was first recognized for its actions in the central nervous system to regulate energy homeostasis but has since been shown to have direct actions on peripheral tissues. In pancreatic β-cells leptin suppresses insulin secretion by increasing KATP channel conductance, which causes membrane hyperpolarization and renders β-cells electrically silent. However, the mechanism by which leptin increases KATP channel conductance had remained unresolved for many years following the initial observation. Recent studies have revealed that leptin increases surface abundance of KATP channels by promoting channel trafficking to the β-cell membrane. Thus, KATP channel trafficking regulation has emerged as a mechanism by which leptin increases KATP channel conductance to regulate β-cell electrical activity and insulin secretion. This review will discuss the leptin signaling pathway that underlies KATP channel trafficking regulation in β-cells.
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Rampérez A, Bartolomé-Martín D, García-Pascual A, Sánchez-Prieto J, Torres M. Photoconversion of FM1-43 Reveals Differences in Synaptic Vesicle Recycling and Sensitivity to Pharmacological Disruption of Actin Dynamics in Individual Synapses. ACS Chem Neurosci 2019; 10:2045-2059. [PMID: 30763065 DOI: 10.1021/acschemneuro.8b00712] [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] [Indexed: 11/29/2022] Open
Abstract
The cycling of synaptic vesicles ensures that neurons can communicate adequately through their synapses on repeated occasions when activity is sustained, and several steps in this cycle are modulated by actin. The effects of pharmacological stabilization of actin with jasplakinolide or its depolymerization with latrunculin A was assessed on the synaptic vesicle cycle at individual boutons of cerebellar granule cells, using FM1-43 imaging to track vesicle recycling and its photoconversion to specifically label recycled organelles. Remarkable differences in the recycling capacity of individual boutons are evident, and their dependence on the actin cytoskeleton for recycling is clear. Disrupting actin dynamics causes a loss of functional boutons, and while this indicates that exo/endocytotic cycling in boutons is fully dependent on such events, this dependence is only partial in other boutons. Indeed, exocytosis and vesicle trafficking are impaired significantly by stabilizing or depolymerizing actin, whereas repositioning recycled vesicles at the active zone seems to be dependent on actin polymerization alone. These findings support the hypothesis that different steps of synaptic vesicle cycling depend on actin dynamics and that such dependence varies among individual boutons.
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Affiliation(s)
- Alberto Rampérez
- Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid 28040, Spain
| | - David Bartolomé-Martín
- Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid 28040, Spain
| | - Angeles García-Pascual
- Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid 28040, Spain
| | - Jose Sánchez-Prieto
- Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid 28040, Spain
| | - Magdalena Torres
- Instituto de Investigación Sanitaria del Hospital Clínico San Carlos (IdISSC), Madrid 28040, Spain
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29
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Zhang X, Han L, Wang Q, Zhang C, Yu Y, Tian J, Kong Z. The host actin cytoskeleton channels rhizobia release and facilitates symbiosome accommodation during nodulation in Medicago truncatula. THE NEW PHYTOLOGIST 2019; 221:1049-1059. [PMID: 30156704 DOI: 10.1111/nph.15423] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2018] [Accepted: 08/02/2018] [Indexed: 05/13/2023]
Abstract
In plants, the actin cytoskeleton plays a central role in regulating intracellular transport and trafficking in the endomembrane system. Work in legumes suggested that during nodulation, the actin cytoskeleton coordinates numerous cellular processes in the development of nitrogen-fixing nodules. However, we lacked live-cell visualizations demonstrating dynamic remodeling of the actin cytoskeleton during infection droplet release and symbiosome development. Here, we generated transgenic Medicago truncatula lines stably expressing the fluorescent actin marker ABD2-GFP, and utilized live-cell imaging to reveal the architecture and dynamics of the actin cytoskeleton during nodule development. Live-cell observations showed that different zones in nitrogen-fixing nodules exhibit distinct actin architectures and infected cells display five characteristic actin architectures during nodule development. Live-cell imaging combined with three-dimensional reconstruction demonstrated that dense filamentous-actin (F-actin) arrays channel the elongation of infection threads and the release of infection droplets, an F-actin network encircles freshly-released rhizobia, and short F-actin fragments and actin dots around radially distributed symbiosomes. Our findings suggest an important role of the actin cytoskeleton in infection droplet release, symbiosome development and maturation, and provide significant insight into the cellular mechanisms underlying nodule development and nitrogen fixation during legume-rhizobia interactions.
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Affiliation(s)
- Xiaxia Zhang
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Libo Han
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Qi Wang
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Chen Zhang
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Yanjun Yu
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Juan Tian
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Zhaosheng Kong
- State Key Laboratory of Plant Genomics, Institute of Microbiology, Chinese Academy of Sciences, Beijing, 100101, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
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30
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Actin Remodeling in Regulated Exocytosis: Toward a Mesoscopic View. Trends Cell Biol 2018; 28:685-697. [DOI: 10.1016/j.tcb.2018.04.004] [Citation(s) in RCA: 51] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 04/05/2018] [Accepted: 04/13/2018] [Indexed: 01/10/2023]
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31
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Vásquez-Navarrete J, Martínez AD, Ory S, Baéz-Matus X, González-Jamett AM, Brauchi S, Caviedes P, Cárdenas AM. RCAN1 Knockdown Reverts Defects in the Number of Calcium-Induced Exocytotic Events in a Cellular Model of Down Syndrome. Front Cell Neurosci 2018; 12:189. [PMID: 30034324 PMCID: PMC6043644 DOI: 10.3389/fncel.2018.00189] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 06/12/2018] [Indexed: 12/15/2022] Open
Abstract
In humans, Down Syndrome (DS) is a condition caused by partial or full trisomy of chromosome 21. Genes present in the DS critical region can result in excess gene dosage, which at least partially can account for DS phenotype. Although regulator of calcineurin 1 (RCAN1) belongs to this region and its ectopic overexpression in neurons impairs transmitter release, synaptic plasticity, learning and memory, the relative contribution of RCAN1 in a context of DS has yet to be clarified. In the present work, we utilized an in vitro model of DS, the CTb neuronal cell line derived from the brain cortex of a trisomy 16 (Ts16) fetal mouse, which reportedly exhibits acetylcholine release impairments compared to CNh cells (a neuronal cell line established from a normal littermate). We analyzed single exocytotic events by using total internal reflection fluorescence microscopy (TIRFM) and the vesicular acetylcholine transporter fused to the pH-sensitive green fluorescent protein (VAChT-pHluorin) as a reporter. Our analyses showed that, compared with control CNh cells, the trisomic CTb cells overexpress RCAN1, and they display a reduced number of Ca2+-induced exocytotic events. Remarkably, RCAN1 knockdown increases the extent of exocytosis at levels comparable to those of CNh cells. These results support a critical contribution of RCAN1 to the exocytosis process in the trisomic condition.
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Affiliation(s)
- Jacqueline Vásquez-Navarrete
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Agustín D Martínez
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Stéphane Ory
- Centre National de la Recherche Scientifique (CNRS UPR 3212), Institut des Neurosciences Cellulaires et Intégratives (INCI), Strasbourg, France
| | - Ximena Baéz-Matus
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Arlek M González-Jamett
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
| | - Sebastián Brauchi
- Department of Physiology, Faculty of Medicine, Universidad Austral de Chile, Valdivia, Chile
| | - Pablo Caviedes
- Programa de Farmacología Molecular y Clínica, ICBM, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,Centro de Biotecnología y Bioingeniería (CeBiB), Departamento de Ingeniería Química, Biotecnología y Materiales, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Santiago, Chile
| | - Ana M Cárdenas
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de Valparaíso, Valparaíso, Chile
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32
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Félix-Martínez GJ, Gil A, Segura J, Villanueva J, Gutíerrez LM. Modeling the influence of co-localized intracellular calcium stores on the secretory response of bovine chromaffin cells. Comput Biol Med 2018; 100:165-175. [PMID: 30015013 DOI: 10.1016/j.compbiomed.2018.06.032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 06/26/2018] [Accepted: 06/27/2018] [Indexed: 11/19/2022]
Abstract
Catecholamines secretion from chromaffin cells is mediated by a Ca2+-dependent process in the submembrane space where the exocytotic machinery is located and high-Ca2+ microdomains (HCMDs) are formed by the coordinated activity of a functional triad composed of Ca2+ channels, endoplasmic reticulum (ER) and mitochondria. It has been observed experimentally that subpopulations of cortical mitochondria and ER associate to secretory sites in bovine chromaffin cells. Here, we study the effect of the geometrical distribution of the co-localized cortical organelles both in the formation of HCMDs in the vicinity of Ca2+ channels and on the secretory activity of bovine chromaffin cells in response to a single voltage pulse. Our simulations indicate that co-localized organelles have a dual role in the formation of HCMDs, having, on the one hand, an amplification effect due to the Ca2+-induced Ca2+-release mechanism from the ER and, on the other, acting as physical barriers to Ca2+ diffusion. In addition, our simulations suggest that the increased levels of Ca2+ in the microdomain enhances the secretion of the vesicles co-localized to the Ca2+ channels. As a whole, our results support the idea that the functional triads formed by Ca2+ channels, subplasmalemma ER and mitochondria have a positive effect on the secretion of catecholamines in bovine chromaffin cells.
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Affiliation(s)
- Gerardo J Félix-Martínez
- Depto. de Matemática Aplicada y Ciencias de la Computación, Universidad de Cantabria, 39005, Santander, Spain; Depto. de Ingeniería Eléctrica, Universidad Autónoma Metropolitana, 09340, Mexico City, Mexico.
| | - Amparo Gil
- Depto. de Matemática Aplicada y Ciencias de la Computación, Universidad de Cantabria, 39005, Santander, Spain.
| | - Javier Segura
- Depto. de Matemáticas, Estadística y Computación, Universidad de Cantabria, 39005, Santander, Spain.
| | - José Villanueva
- Instituto de Neurociencias, Centro Mixto Universidad Miguel Hernández-CSIC, Sant Joan d'Alacant, 03550, Alicante, Spain.
| | - Luis M Gutíerrez
- Instituto de Neurociencias, Centro Mixto Universidad Miguel Hernández-CSIC, Sant Joan d'Alacant, 03550, Alicante, Spain.
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33
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Liao CP, Li H, Lee HH, Chien CT, Pan CL. Cell-Autonomous Regulation of Dendrite Self-Avoidance by the Wnt Secretory Factor MIG-14/Wntless. Neuron 2018; 98:320-334.e6. [DOI: 10.1016/j.neuron.2018.03.031] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2017] [Revised: 02/06/2018] [Accepted: 03/16/2018] [Indexed: 11/26/2022]
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34
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Licon-Munoz Y, Michel V, Fordyce CA, Parra KJ. F-actin reorganization by V-ATPase inhibition in prostate cancer. Biol Open 2017; 6:1734-1744. [PMID: 29038303 PMCID: PMC5703614 DOI: 10.1242/bio.028837] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The vacuolar ATPase (V-ATPase) proton pump sustains cellular pH homeostasis, and its inhibition triggers numerous stress responses. However, the cellular mechanisms involved remain largely elusive in cancer cells. We studied V-ATPase in the prostate cancer (PCa) cell line PC-3, which has characteristics of highly metastatic PCa. V-ATPase inhibitors impaired endo-lysosomal pH, vesicle trafficking, migration, and invasion. V-ATPase accrual in the Golgi and recycling endosomes suggests that traffic of internalized membrane vesicles back to the plasma membrane was particularly impaired. Directed movement provoked co-localization of V-ATPase containing vesicles with F-actin near the leading edge of migrating cells. V-ATPase inhibition prompted prominent F-actin cytoskeleton reorganization. Filopodial projections were reduced, which related to reduced migration velocity. F-actin formed novel cytoplasmic rings. F-actin rings increased with extended exposure to sublethal concentrations of V-ATPase inhibitors, from 24 to 48 h, as the amount of alkalinized endo-lysosomal vesicles increased. Studies with chloroquine indicated that F-actin rings formation was pH-dependent. We hypothesize that these novel F-actin rings assemble to overcome widespread traffic defects caused by V-ATPase inhibition, similar to F-actin rings on the surface of exocytic organelles. Summary: V-ATPase activates multiple stress responses. In prostate cancer, sub-lethal concentrations of V-ATPase inhibitors trigger widespread traffic defects. F-actin assembles into rings that mimic those seen during regulated exocytosis.
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Affiliation(s)
- Yamhilette Licon-Munoz
- Department of Biochemistry and Molecular Biology, School of Medicine, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - Vera Michel
- Department of Biochemistry and Molecular Biology, School of Medicine, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - Colleen A Fordyce
- Department of Biochemistry and Molecular Biology, School of Medicine, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - Karlett J Parra
- Department of Biochemistry and Molecular Biology, School of Medicine, University of New Mexico, Albuquerque, New Mexico 87131, USA
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35
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Li L, Gao Y, Chen H, Jesus T, Tang E, Li N, Lian Q, Ge RS, Cheng CY. Cell polarity, cell adhesion, and spermatogenesis: role of cytoskeletons. F1000Res 2017; 6:1565. [PMID: 28928959 PMCID: PMC5580414 DOI: 10.12688/f1000research.11421.1] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/21/2017] [Indexed: 01/13/2023] Open
Abstract
In the rat testis, studies have shown that cell polarity, in particular spermatid polarity, to support spermatogenesis is conferred by the coordinated efforts of the Par-, Crumbs-, and Scribble-based polarity complexes in the seminiferous epithelium. Furthermore, planar cell polarity (PCP) is conferred by PCP proteins such as Van Gogh-like 2 (Vangl2) in the testis. On the other hand, cell junctions at the Sertoli cell–spermatid (steps 8–19) interface are exclusively supported by adhesion protein complexes (for example, α6β1-integrin-laminin-α3,β3,γ3 and nectin-3-afadin) at the actin-rich apical ectoplasmic specialization (ES) since the apical ES is the only anchoring device in step 8–19 spermatids. For cell junctions at the Sertoli cell–cell interface, they are supported by adhesion complexes at the actin-based basal ES (for example, N-cadherin-β-catenin and nectin-2-afadin), tight junction (occludin-ZO-1 and claudin 11-ZO-1), and gap junction (connexin 43-plakophilin-2) and also intermediate filament-based desmosome (for example, desmoglein-2-desmocollin-2). In short, the testis-specific actin-rich anchoring device known as ES is crucial to support spermatid and Sertoli cell adhesion. Accumulating evidence has shown that the Par-, Crumbs-, and Scribble-based polarity complexes and the PCP Vangl2 are working in concert with actin- or microtubule-based cytoskeletons (or both) and these polarity (or PCP) protein complexes exert their effects through changes in the organization of the cytoskeletal elements across the seminiferous epithelium of adult rat testes. As such, there is an intimate relationship between cell polarity, cell adhesion, and cytoskeletal function in the testis. Herein, we critically evaluate these recent findings based on studies on different animal models. We also suggest some crucial future studies to be performed.
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Affiliation(s)
- Linxi Li
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, New York, USA.,The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Ying Gao
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, New York, USA
| | - Haiqi Chen
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, New York, USA
| | - Tito Jesus
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, New York, USA
| | - Elizabeth Tang
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, New York, USA
| | - Nan Li
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, New York, USA
| | - Qingquan Lian
- The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Ren-Shan Ge
- The Second Affiliated Hospital & Yuying Children's Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - C Yan Cheng
- The Mary M. Wohlford Laboratory for Male Contraceptive Research, Center for Biomedical Research, New York, USA
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36
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Wang J, Richards DA. The actin binding protein scinderin acts in PC12 cells to tether dense-core vesicles prior to secretion. Mol Cell Neurosci 2017; 85:12-18. [PMID: 28823945 DOI: 10.1016/j.mcn.2017.08.003] [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: 03/13/2017] [Revised: 08/07/2017] [Accepted: 08/16/2017] [Indexed: 11/18/2022] Open
Abstract
Mechanistic understanding of the control of vesicle motion from within a secretory cell to the site of exocytosis remains incomplete. In this work, we have used total internal reflection (TIRF) microscopy to examine the mobility of secretory vesicles at the plasma membrane. Under resting conditions, we found vesicles showed little lateral mobility. Anchoring of vesicles in this membrane proximal compartment could be disrupted with latrunculin A, indicating an apparent actin dependent process. A candidate intermediary between vesicles and the actin skeleton is the actin binding protein scinderin. Co-transfection of an shRNA construct against scinderin blocked secretion, and also increased the mobility of vesicles in the membrane-proximal section of the cell, indicating a dual role for scinderin in secretion; tethering vesicles to the cytoskeleton, as well as liberating them following stimulation through the previously described calcium dependent actin severing activity. Analysis of lipid dependence indicates that scinderin exhibits calcium dependent binding to phosphatidyl-inositol monophosphate, providing a possible mechanism for vesicle binding.
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Affiliation(s)
- J Wang
- Department of Anesthesia, Cincinnati Children's Hospital Medical Center, MLC2001, 3333 Burnet Avenue, Cincinnati, OH 45229, United States
| | - D A Richards
- Department of Anesthesia, Cincinnati Children's Hospital Medical Center, MLC2001, 3333 Burnet Avenue, Cincinnati, OH 45229, United States; Department of Basic Pharmaceutical Sciences, Husson University School of Pharmacy, 1 College Circle, Bangor, ME 04401, United States.
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37
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Tomatis VM, Josh P, Papadopulos A, Gormal RS, Lanoue V, Martin S, Meunier FA. ENA/VASP proteins regulate exocytosis by mediating myosin VI-dependent recruitment of secretory granules to the cortical actin network. Mol Cell Neurosci 2017; 84:100-111. [PMID: 28784263 DOI: 10.1016/j.mcn.2017.07.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 07/17/2017] [Accepted: 07/27/2017] [Indexed: 10/24/2022] Open
Abstract
In neurosecretory cells, myosin VI associated with secretory granules (SGs) mediates their activity-dependent recruitment to the cortical actin network and is necessary to sustain exocytosis. The mechanism by which myosin VI interacts with SGs is unknown. Using a myosin VI pull-down assay and mass spectrometry we identified Mena, a member of the ENA/VASP family, as a myosin VI binding partner in PC12 cells, and confirmed that Mena colocalized with myosin VI on SGs. Using a knock-sideways approach to inactivate the ENA/VASP family members by mitochondrial relocation, we revealed a concomitant redistribution of myosin VI. This was ensued by a reduction in the association of myosin VI with SGs, a decreased SG mobility and density in proximity to the plasma membrane as well as decreased evoked exocytosis. These data demonstrate that ENA/VASP proteins regulate SG exocytosis through modulating the activity of myosin VI.
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Affiliation(s)
- Vanesa M Tomatis
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Queensland 4072, Australia; Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Peter Josh
- Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Andreas Papadopulos
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Queensland 4072, Australia; Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Rachel S Gormal
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Queensland 4072, Australia; Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Vanessa Lanoue
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Queensland 4072, Australia; Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Sally Martin
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Queensland 4072, Australia; Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia
| | - Frédéric A Meunier
- Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Queensland 4072, Australia; Queensland Brain Institute, The University of Queensland, Brisbane, Queensland 4072, Australia.
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38
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Gutiérrez LM, Villanueva J. The role of F-actin in the transport and secretion of chromaffin granules: an historic perspective. Pflugers Arch 2017; 470:181-186. [PMID: 28730385 PMCID: PMC5748413 DOI: 10.1007/s00424-017-2040-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Revised: 07/13/2017] [Accepted: 07/14/2017] [Indexed: 12/23/2022]
Abstract
Actin is one of the most ubiquitous protein playing fundamental roles in a variety of cellular processes. Since early in the 1980s, it was evident that filamentous actin (F-actin) formed a peripheral cortical barrier that prevented vesicles to access secretory sites in chromaffin cells in culture. Later, around 2000, it was described that the F-actin structure accomplishes a dual role serving both vesicle transport and retentive purposes and undergoing dynamic transient changes during cell stimulation. The complex role of the F-actin cytoskeleton in neuroendocrine secretion was further evidenced when it has been proved to participate in the scaffold structure holding together the secretory machinery at active sites and participate in the generation of mechanical forces that drive the opening of the fusion pore, during the first decade of the present century. The complex vision of the multiple roles of F-actin in secretion we have acquired to date comes largely from studies performed on traditional 2D cultures of primary cells; however, recent evidences suggest that these may not accurately mimic the 3D in vivo environment, and thus, more work is now needed on adrenomedullary cells kept in a more “native” configuration to fully understand the role of F-actin in regulating chromaffin granule transport and secretion under physiological conditions.
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Affiliation(s)
- Luis M Gutiérrez
- Instituto de Neurociencias de Alicante, Consejo Superior de Investigaciones Científicas-Universidad Miguel Hernández, Sant Joan d'Alacant, 03550, Alicante, Spain.
| | - José Villanueva
- Instituto de Neurociencias de Alicante, Consejo Superior de Investigaciones Científicas-Universidad Miguel Hernández, Sant Joan d'Alacant, 03550, Alicante, Spain
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39
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Delestre-Delacour C, Carmon O, Laguerre F, Estay-Ahumada C, Courel M, Elias S, Jeandel L, Rayo MV, Peinado JR, Sengmanivong L, Gasman S, Coudrier E, Anouar Y, Montero-Hadjadje M. Myosin 1b and F-actin are involved in the control of secretory granule biogenesis. Sci Rep 2017; 7:5172. [PMID: 28701771 PMCID: PMC5507975 DOI: 10.1038/s41598-017-05617-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2017] [Accepted: 05/31/2017] [Indexed: 12/22/2022] Open
Abstract
Hormone secretion relies on secretory granules which store hormones in endocrine cells and release them upon cell stimulation. The molecular events leading to hormone sorting and secretory granule formation at the level of the TGN are still elusive. Our proteomic analysis of purified whole secretory granules or secretory granule membranes uncovered their association with the actomyosin components myosin 1b, actin and the actin nucleation complex Arp2/3. We found that myosin 1b controls the formation of secretory granules and the associated regulated secretion in both neuroendocrine cells and chromogranin A-expressing COS7 cells used as a simplified model of induced secretion. We show that F-actin is also involved in secretory granule biogenesis and that myosin 1b cooperates with Arp2/3 to recruit F-actin to the Golgi region where secretory granules bud. These results provide the first evidence that components of the actomyosin complex promote the biogenesis of secretory granules and thereby regulate hormone sorting and secretion.
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Affiliation(s)
- Charlène Delestre-Delacour
- Normandie Univ, UNIROUEN, INSERM, U1239, Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Institut de Recherche et d'Innovation Biomédicale de Normandie, 76000, Rouen, France
| | - Ophélie Carmon
- Normandie Univ, UNIROUEN, INSERM, U1239, Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Institut de Recherche et d'Innovation Biomédicale de Normandie, 76000, Rouen, France
| | - Fanny Laguerre
- Normandie Univ, UNIROUEN, INSERM, U1239, Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Institut de Recherche et d'Innovation Biomédicale de Normandie, 76000, Rouen, France
| | - Catherine Estay-Ahumada
- Université de Strasbourg, CNRS UPR 3212, Institut des Neurosciences Cellulaires et Intégratives, 67000, Strasbourg, France
| | - Maïté Courel
- Normandie Univ, UNIROUEN, INSERM, U1239, Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Institut de Recherche et d'Innovation Biomédicale de Normandie, 76000, Rouen, France.,CNRS-UPMC FRE3402, Pierre et Marie Curie University, 75252, Paris, Cedex 05, France
| | - Salah Elias
- Normandie Univ, UNIROUEN, INSERM, U1239, Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Institut de Recherche et d'Innovation Biomédicale de Normandie, 76000, Rouen, France.,University of Oxford, Sir William Dunn School of Pathology, Oxford, Oxfordshire, United Kingdom
| | - Lydie Jeandel
- Normandie Univ, UNIROUEN, INSERM, U1239, Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Institut de Recherche et d'Innovation Biomédicale de Normandie, 76000, Rouen, France
| | - Margarita Villar Rayo
- Instituto de Investigación en Recursos Cinegéticos, Proteomics Core Facility, 13071, Ciudad Real, Spain
| | - Juan R Peinado
- Laboratory of oxidative stress and neurodegeneration, Facultad de Medicina de Ciudad Real, 13071, Ciudad Real, Spain
| | - Lucie Sengmanivong
- Institut Curie - PSL Research University, Membrane Dynamics and Mechanics of Intracellular Signaling Laboratory, Nikon Imaging Centre, 75005, Paris, France
| | - Stéphane Gasman
- Université de Strasbourg, CNRS UPR 3212, Institut des Neurosciences Cellulaires et Intégratives, 67000, Strasbourg, France
| | - Evelyne Coudrier
- CNRS UMR 144 Cell Signaling and Morphogenesis, Institut Curie, 75005, Paris, France
| | - Youssef Anouar
- Normandie Univ, UNIROUEN, INSERM, U1239, Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Institut de Recherche et d'Innovation Biomédicale de Normandie, 76000, Rouen, France.
| | - Maité Montero-Hadjadje
- Normandie Univ, UNIROUEN, INSERM, U1239, Laboratoire de Différenciation et Communication Neuronale et Neuroendocrine, Institut de Recherche et d'Innovation Biomédicale de Normandie, 76000, Rouen, France.
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40
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Yang C, Li YS, Wang QX, Huang K, Wei JW, Wang YF, Zhou JH, Yi KK, Zhang KL, Zhou BC, Liu C, Zeng L, Kang CS. EGFR/EGFRvIII remodels the cytoskeleton via epigenetic silencing of AJAP1 in glioma cells. Cancer Lett 2017. [PMID: 28634045 DOI: 10.1016/j.canlet.2017.06.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
EGFR amplification and mutations are the most common oncogenic events in GBM. EGFR overexpression correlates with GBM invasion, but the underlying mechanisms are poorly understood. In a previous study, we showed that AJAP1 is involved in regulating F-actin to inhibit the invasive ability of GBM. In addition, in a GBM cell line, the AJAP1 promoter was highly bound by H3K27me3 and, through bioinformatics analysis, we found that AJAP1 expression was negatively correlated with EGFR. In this study, we found that the pathway downstream of EGFR had a higher activation level in GBM cell lines, which led to excessive tumor suppressor silencing. Therefore, we deduced that in glioma cells, the pathway downstream of EGFR remodels the cytoskeleton via AJAP1 epigenetic silencing to enhance invasion. Furthermore, MK2206 reversed AJAP1 downregulation by inhibiting the EGFR pathway. In vivo, MK2206 also inhibited the proliferation and local invasion of 87-EGFRvIII. These data suggest that activation of the EGFR signal transduction pathway genetically silences anti-oncogenes to enhance GBM malignancy. MK2206 might be a promising therapeutic for EGFR/EGFRvIII-positive GBMs.
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Affiliation(s)
- Chao Yang
- Department of Neurosurgery, Tianjin Medical University General Hospital, Laboratory of Neuro-Oncology, Tianjin Neurological Institute, Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin Key Laboratory of Injuries, Variations and Regeneration of Nervous System, Tianjin 300052, China
| | - Yan-Sheng Li
- Department of Neurosurgery, Tianjin Medical University General Hospital, Laboratory of Neuro-Oncology, Tianjin Neurological Institute, Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin Key Laboratory of Injuries, Variations and Regeneration of Nervous System, Tianjin 300052, China
| | - Qi-Xue Wang
- Department of Neurosurgery, Tianjin Medical University General Hospital, Laboratory of Neuro-Oncology, Tianjin Neurological Institute, Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin Key Laboratory of Injuries, Variations and Regeneration of Nervous System, Tianjin 300052, China
| | - Kai Huang
- Department of Neurosurgery, Tianjin Medical University General Hospital, Laboratory of Neuro-Oncology, Tianjin Neurological Institute, Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin Key Laboratory of Injuries, Variations and Regeneration of Nervous System, Tianjin 300052, China
| | - Jian-Wei Wei
- Department of Neurosurgery, Tianjin Medical University General Hospital, Laboratory of Neuro-Oncology, Tianjin Neurological Institute, Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin Key Laboratory of Injuries, Variations and Regeneration of Nervous System, Tianjin 300052, China
| | - Yun-Fei Wang
- Department of Neurosurgery, Tianjin Medical University General Hospital, Laboratory of Neuro-Oncology, Tianjin Neurological Institute, Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin Key Laboratory of Injuries, Variations and Regeneration of Nervous System, Tianjin 300052, China
| | - Jun-Hu Zhou
- Department of Neurosurgery, Tianjin Medical University General Hospital, Laboratory of Neuro-Oncology, Tianjin Neurological Institute, Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin Key Laboratory of Injuries, Variations and Regeneration of Nervous System, Tianjin 300052, China
| | - Kai-Kai Yi
- Department of Neurosurgery, Tianjin Medical University General Hospital, Laboratory of Neuro-Oncology, Tianjin Neurological Institute, Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin Key Laboratory of Injuries, Variations and Regeneration of Nervous System, Tianjin 300052, China
| | - Kai-Liang Zhang
- Department of Neurosurgery, Qilu Hospital of Shandong University, Brain Science Research Institute, Shandong University, China
| | - Bing-Cong Zhou
- Department of Neurosurgery, Tianjin Medical University General Hospital, Laboratory of Neuro-Oncology, Tianjin Neurological Institute, Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin Key Laboratory of Injuries, Variations and Regeneration of Nervous System, Tianjin 300052, China
| | - Cong Liu
- Department of Neurosurgery, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, PR China
| | - Liang Zeng
- Department of Neurosurgery, Tongji Hospital, Huazhong University of Science and Technology, Wuhan, PR China.
| | - Chun-Sheng Kang
- Department of Neurosurgery, Tianjin Medical University General Hospital, Laboratory of Neuro-Oncology, Tianjin Neurological Institute, Key Laboratory of Post-trauma Neuro-repair and Regeneration in Central Nervous System, Ministry of Education, Tianjin Key Laboratory of Injuries, Variations and Regeneration of Nervous System, Tianjin 300052, China.
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41
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Papadopulos A. Membrane shaping by actin and myosin during regulated exocytosis. Mol Cell Neurosci 2017; 84:93-99. [PMID: 28536001 DOI: 10.1016/j.mcn.2017.05.006] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2017] [Revised: 04/21/2017] [Accepted: 05/19/2017] [Indexed: 12/01/2022] Open
Abstract
The cortical actin network in neurosecretory cells is a dense mesh of actin filaments underlying the plasma membrane. Interaction of actomyosin with vesicular membranes or the plasma membrane is vital for tethering, retention, transport as well as fusion and fission of exo- and endocytic membrane structures. During regulated exocytosis the cortical actin network undergoes dramatic changes in morphology to accommodate vesicle docking, fusion and replenishment. Most of these processes involve plasma membrane Phosphoinositides (PIP) and investigating the interactions between the actin cortex and secretory structures has become a hotbed for research in recent years. Actin remodelling leads to filopodia outgrowth and the creation of new fusion sites in neurosecretory cells and actin, myosin and dynamin actively shape and maintain the fusion pore of secretory vesicles. Changes in viscoelastic properties of the actin cortex can facilitate vesicular transport and lead to docking and priming of vesicle at the plasma membrane. Small GTPase actin mediators control the state of the cortical actin network and influence vesicular access to their docking and fusion sites. These changes potentially affect membrane properties such as tension and fluidity as well as the mobility of embedded proteins and could influence the processes leading to both exo- and endocytosis. Here we discuss the multitudes of actin and membrane interactions that control successive steps underpinning regulated exocytosis.
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Affiliation(s)
- Andreas Papadopulos
- The Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD, 4072, Australia.
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42
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González-Jamett AM, Guerra MJ, Olivares MJ, Haro-Acuña V, Baéz-Matus X, Vásquez-Navarrete J, Momboisse F, Martinez-Quiles N, Cárdenas AM. The F-Actin Binding Protein Cortactin Regulates the Dynamics of the Exocytotic Fusion Pore through its SH3 Domain. Front Cell Neurosci 2017; 11:130. [PMID: 28522963 PMCID: PMC5415606 DOI: 10.3389/fncel.2017.00130] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 04/18/2017] [Indexed: 11/20/2022] Open
Abstract
Upon cell stimulation, the network of cortical actin filaments is rearranged to facilitate the neurosecretory process. This actin rearrangement includes both disruption of the preexisting actin network and de novo actin polymerization. However, the mechanism by which a Ca2+ signal elicits the formation of new actin filaments remains uncertain. Cortactin, an actin-binding protein that promotes actin polymerization in synergy with the nucleation promoting factor N-WASP, could play a key role in this mechanism. We addressed this hypothesis by analyzing de novo actin polymerization and exocytosis in bovine adrenal chromaffin cells expressing different cortactin or N-WASP domains, or cortactin mutants that fail to interact with proline-rich domain (PRD)-containing proteins, including N-WASP, or to be phosphorylated by Ca2+-dependent kinases, such as ERK1/2 and Src. Our results show that the activation of nicotinic receptors in chromaffin cells promotes cortactin translocation to the cell cortex, where it colocalizes with actin filaments. We further found that, in association with PRD-containing proteins, cortactin contributes to the Ca2+-dependent formation of F-actin, and regulates fusion pore dynamics and the number of exocytotic events induced by activation of nicotinic receptors. However, whereas the actions of cortactin on the fusion pore dynamics seems to depend on the availability of monomeric actin and its phosphorylation by ERK1/2 and Src kinases, cortactin regulates the extent of exocytosis by a mechanism independent of actin polymerization. Together our findings point out a role for cortactin as a critical modulator of actin filament formation and exocytosis in neuroendocrine cells.
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Affiliation(s)
- Arlek M González-Jamett
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de ValparaísoValparaíso, Chile
| | - María J Guerra
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de ValparaísoValparaíso, Chile
| | - María J Olivares
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de ValparaísoValparaíso, Chile
| | - Valentina Haro-Acuña
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de ValparaísoValparaíso, Chile
| | - Ximena Baéz-Matus
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de ValparaísoValparaíso, Chile
| | - Jacqueline Vásquez-Navarrete
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de ValparaísoValparaíso, Chile
| | - Fanny Momboisse
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de ValparaísoValparaíso, Chile
| | - Narcisa Martinez-Quiles
- Departamento de Microbiología (Inmunología), Facultad de Medicina, Universidad Complutense de MadridMadrid, Spain
| | - Ana M Cárdenas
- Centro Interdisciplinario de Neurociencia de Valparaíso, Facultad de Ciencias, Universidad de ValparaísoValparaíso, Chile
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43
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Gimenez-Molina Y, Villanueva J, Nanclares C, Lopez-Font I, Viniegra S, Francés MDM, Gandia L, Gil A, Gutiérrez LM. The Differential Organization of F-Actin Alters the Distribution of Organelles in Cultured When Compared to Native Chromaffin Cells. Front Cell Neurosci 2017; 11:135. [PMID: 28522964 PMCID: PMC5415619 DOI: 10.3389/fncel.2017.00135] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2017] [Accepted: 04/21/2017] [Indexed: 11/17/2022] Open
Abstract
Cultured bovine chromaffin cells have been used extensively as a neuroendocrine model to study regulated secretion. In order to extend such experimental findings to the physiological situation, it is necessary to study mayor cellular structures affecting secretion in cultured cells with their counterparts present in the adrenomedullary tissue. F-actin concentrates in a peripheral ring in cultured cells, as witnessed by phalloidin–rodhamine labeling, while extends throughout the cytoplasm in native cells. This result is also confirmed when studying the localization of α-fodrin, a F-actin-associated protein. Furthermore, as a consequence of this redistribution of F-actin, we observed that chromaffin granules and mitochondria located into two different cortical and internal populations in cultured cells, whereas they are homogeneously distributed throughout the cytoplasm in the adrenomedullary tissue. Nevertheless, secretion from isolated cells and adrenal gland pieces is remarkably similar when measured by amperometry. Finally, we generate mathematical models to consider how the distribution of organelles affects the secretory kinetics of intact and cultured cells. Our results imply that we have to consider F-actin structural changes to interpret functional data obtained in cultured neuroendocrine cells.
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Affiliation(s)
- Yolanda Gimenez-Molina
- Instituto de Neurociencias, Centro Mixto del Consejo Superior de Investigaciones Científicas, Universidad Miguel HernándezAlicante, Spain
| | - José Villanueva
- Instituto de Neurociencias, Centro Mixto del Consejo Superior de Investigaciones Científicas, Universidad Miguel HernándezAlicante, Spain
| | - Carmen Nanclares
- Instituto Teófilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de MadridMadrid, Spain
| | - Inmaculada Lopez-Font
- Instituto de Neurociencias, Centro Mixto del Consejo Superior de Investigaciones Científicas, Universidad Miguel HernándezAlicante, Spain.,Centro de Investigación Biomédica en Red de Enfermedades NeurodegenerativasAlicante, Spain
| | - Salvador Viniegra
- Instituto de Neurociencias, Centro Mixto del Consejo Superior de Investigaciones Científicas, Universidad Miguel HernándezAlicante, Spain
| | - Maria Del Mar Francés
- Instituto de Neurociencias, Centro Mixto del Consejo Superior de Investigaciones Científicas, Universidad Miguel HernándezAlicante, Spain
| | - Luis Gandia
- Instituto Teófilo Hernando, Departamento de Farmacología y Terapéutica, Facultad de Medicina, Universidad Autónoma de MadridMadrid, Spain
| | - Amparo Gil
- Department Matemática Aplicada y Ciencias de la Computación, Universidad de CantabriaSantander, Spain
| | - Luis M Gutiérrez
- Instituto de Neurociencias, Centro Mixto del Consejo Superior de Investigaciones Científicas, Universidad Miguel HernándezAlicante, Spain
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44
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Dun AR, Lord GJ, Wilson RS, Kavanagh DM, Cialowicz KI, Sugita S, Park S, Yang L, Smyth AM, Papadopulos A, Rickman C, Duncan RR. Navigation through the Plasma Membrane Molecular Landscape Shapes Random Organelle Movement. Curr Biol 2017; 27:408-414. [PMID: 28089515 PMCID: PMC5300901 DOI: 10.1016/j.cub.2016.12.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 09/05/2016] [Accepted: 12/02/2016] [Indexed: 12/13/2022]
Abstract
Eukaryotic plasma membrane organization theory has long been controversial, in part due to a dearth of suitably high-resolution techniques to probe molecular architecture in situ and integrate information from diverse data streams [1]. Notably, clustered patterning of membrane proteins is a commonly conserved feature across diverse protein families (reviewed in [2]), including the SNAREs [3], SM proteins [4, 5], ion channels [6, 7], and receptors (e.g., [8]). Much effort has gone into analyzing the behavior of secretory organelles [9-13], and understanding the relationship between the membrane and proximal organelles [4, 5, 12, 14] is an essential goal for cell biology as broad concepts or rules may be established. Here we explore the generally accepted model that vesicles at the plasmalemma are guided by cytoskeletal tracks to specific sites on the membrane that have clustered molecular machinery for secretion [15], organized in part by the local lipid composition [16]. To increase our understanding of these fundamental processes, we integrated nanoscopy and spectroscopy of the secretory machinery with organelle tracking data in a mathematical model, iterating with knockdown cell models. We find that repeated routes followed by successive vesicles, the re-use of similar fusion sites, and the apparently distinct vesicle "pools" are all fashioned by the Brownian behavior of organelles overlaid on navigation between non-reactive secretory protein molecular depots patterned at the plasma membrane.
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Affiliation(s)
- Alison R Dun
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh EH14 4AS, UK; Edinburgh Super-Resolution Imaging Consortium
| | - Gabriel J Lord
- Department of Mathematics, Maxwell Institute, MACS, Heriot-Watt University, Edinburgh EH14 4AS, UK
| | - Rhodri S Wilson
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh EH14 4AS, UK; Edinburgh Super-Resolution Imaging Consortium
| | - Deirdre M Kavanagh
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh EH14 4AS, UK; Edinburgh Super-Resolution Imaging Consortium
| | - Katarzyna I Cialowicz
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh EH14 4AS, UK; Edinburgh Super-Resolution Imaging Consortium
| | - Shuzo Sugita
- Toronto Western Research Institute, Room 11-432, McLaughlin Wing, 399 Bathurst St., Toronto, ON M5T 2S8, Canada
| | - Seungmee Park
- Toronto Western Research Institute, Room 11-432, McLaughlin Wing, 399 Bathurst St., Toronto, ON M5T 2S8, Canada
| | - Lei Yang
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh EH14 4AS, UK; Edinburgh Super-Resolution Imaging Consortium
| | - Annya M Smyth
- Centre for Inflammation Research, University of Edinburgh, The Queen's Medical Research Institute, 47 Little France Crescent, Edinburgh EH16 4TJ, UK
| | - Andreas Papadopulos
- The Clem Jones Centre for Ageing Dementia Research, Queensland Brain Institute, The University of Queensland, Brisbane, QLD 4072, Australia
| | - Colin Rickman
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh EH14 4AS, UK; Edinburgh Super-Resolution Imaging Consortium
| | - Rory R Duncan
- Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh EH14 4AS, UK; Edinburgh Super-Resolution Imaging Consortium.
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