1
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Blake TCA, Fox HM, Urbančič V, Ravishankar R, Wolowczyk A, Allgeyer ES, Mason J, Danuser G, Gallop JL. Filopodial protrusion driven by density-dependent Ena-TOCA-1 interactions. J Cell Sci 2024; 137:jcs261057. [PMID: 38323924 PMCID: PMC11006392 DOI: 10.1242/jcs.261057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Accepted: 01/29/2024] [Indexed: 02/08/2024] Open
Abstract
Filopodia are narrow actin-rich protrusions with important roles in neuronal development where membrane-binding adaptor proteins, such as I-BAR- and F-BAR-domain-containing proteins, have emerged as upstream regulators that link membrane interactions to actin regulators such as formins and proteins of the Ena/VASP family. Both the adaptors and their binding partners are part of diverse and redundant protein networks that can functionally compensate for each other. To explore the significance of the F-BAR domain-containing neuronal membrane adaptor TOCA-1 (also known as FNBP1L) in filopodia we performed a quantitative analysis of TOCA-1 and filopodial dynamics in Xenopus retinal ganglion cells, where Ena/VASP proteins have a native role in filopodial extension. Increasing the density of TOCA-1 enhances Ena/VASP protein binding in vitro, and an accumulation of TOCA-1, as well as its coincidence with Ena, correlates with filopodial protrusion in vivo. Two-colour single-molecule localisation microscopy of TOCA-1 and Ena supports their nanoscale association. TOCA-1 clusters promote filopodial protrusion and this depends on a functional TOCA-1 SH3 domain and activation of Cdc42, which we perturbed using the small-molecule inhibitor CASIN. We propose that TOCA-1 clusters act independently of membrane curvature to recruit and promote Ena activity for filopodial protrusion.
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Affiliation(s)
- Thomas C. A. Blake
- Wellcome/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - Helen M. Fox
- Wellcome/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - Vasja Urbančič
- Wellcome/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - Roshan Ravishankar
- Lyda Hill Department of Bioinformatics, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Adam Wolowczyk
- Wellcome/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - Edward S. Allgeyer
- Wellcome/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK
- Department of Genetics, University of Cambridge, Cambridge CB2 3EH, UK
| | - Julia Mason
- Wellcome/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
| | - Gaudenz Danuser
- Lyda Hill Department of Bioinformatics, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Jennifer L. Gallop
- Wellcome/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, UK
- Department of Biochemistry, University of Cambridge, Cambridge CB2 1QW, UK
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2
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El Alaoui F, Casuso I, Sanchez-Fuentes D, Arpin-Andre C, Rathar R, Baecker V, Castro A, Lorca T, Viaud J, Vassilopoulos S, Carretero-Genevrier A, Picas L. Structural organization and dynamics of FCHo2 docking on membranes. eLife 2022; 11:e73156. [PMID: 35044298 PMCID: PMC8798043 DOI: 10.7554/elife.73156] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 01/18/2022] [Indexed: 11/24/2022] Open
Abstract
Clathrin-mediated endocytosis (CME) is a central trafficking pathway in eukaryotic cells regulated by phosphoinositides. The plasma membrane phosphatidylinositol-4,5-bisphosphate (PI(4,5)P2) plays an instrumental role in driving CME initiation. The F-BAR domain-only protein 1 and 2 complex (FCHo1/2) is among the early proteins that reach the plasma membrane, but the exact mechanisms triggering its recruitment remain elusive. Here, we show the molecular dynamics of FCHo2 self-assembly on membranes by combining minimal reconstituted in vitro and cellular systems. Our results indicate that PI(4,5)P2 domains assist FCHo2 docking at specific membrane regions, where it self-assembles into ring-like-shaped protein patches. We show that the binding of FCHo2 on cellular membranes promotes PI(4,5)P2 clustering at the boundary of cargo receptors and that this accumulation enhances clathrin assembly. Thus, our results provide a mechanistic framework that could explain the recruitment of early PI(4,5)P2-interacting proteins at endocytic sites.
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Affiliation(s)
- Fatima El Alaoui
- Institut de Recherche en Infectiologie de Montpellier (IRIM), CNRS UMR 9004, Université de MontpellierMontpellierFrance
| | | | - David Sanchez-Fuentes
- Institut d'Électronique et des Systèmes (IES), CNRS UMR 5214, Université de MontpellierMontpellierFrance
| | - Charlotte Arpin-Andre
- Institut de Recherche en Infectiologie de Montpellier (IRIM), CNRS UMR 9004, Université de MontpellierMontpellierFrance
| | - Raissa Rathar
- Institut d'Électronique et des Systèmes (IES), CNRS UMR 5214, Université de MontpellierMontpellierFrance
| | - Volker Baecker
- Montpellier Ressources Imagerie, BioCampus Montpellier, CNRS, INSERM, Université de MontpellierMontpellierFrance
| | - Anna Castro
- Centre de Biologie Cellulaire de Montpellier (CRBM), CNRS UMR UMR 5237, Université de MontpellierMontpellierFrance
| | - Thierry Lorca
- Centre de Biologie Cellulaire de Montpellier (CRBM), CNRS UMR UMR 5237, Université de MontpellierMontpellierFrance
| | - Julien Viaud
- INSERM UMR1297, Institute of Metabolic and Cardiovascular Diseases (I2MC), University of Toulouse, Paul Sabatier UniversityToulouseFrance
| | - Stéphane Vassilopoulos
- Sorbonne Université, INSERM, Institute of Myology, Centre of Research in Myology, UMRS 974ParisFrance
| | - Adrian Carretero-Genevrier
- Institut d'Électronique et des Systèmes (IES), CNRS UMR 5214, Université de MontpellierMontpellierFrance
| | - Laura Picas
- Institut de Recherche en Infectiologie de Montpellier (IRIM), CNRS UMR 9004, Université de MontpellierMontpellierFrance
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3
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Mei Q, Li H, Liu Y, Wang X, Xiang W. Advances in the study of CDC42 in the female reproductive system. J Cell Mol Med 2021; 26:16-24. [PMID: 34859585 PMCID: PMC8742232 DOI: 10.1111/jcmm.17088] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 11/08/2021] [Accepted: 11/12/2021] [Indexed: 12/19/2022] Open
Abstract
CDC42 is a member of the Rho‐GTPase family and is involved in a variety of cellular functions including regulation of cell cycle progression, constitution of the actin backbone and membrane transport. In particular, CDC42 plays a key role in the establishment of polarity in female vertebrate oocytes, and essential to this major regulatory role is its local occupation of specific regions of the cell to ensure that the contractile ring is assembled at the right time and place to ensure proper gametogenesis. The multifactor controlled ‘inactivation‐activation’ process of CDC42 also allows it to play an important role in the multilevel signalling network, and the synergistic regulation of multiple genes ensures maximum precision during gametogenesis. The purpose of this paper is to review the role of CDC42 in the control of gametogenesis and to explore its related mechanisms, with the aim of further understanding the great research potential of CDC42 in female vertebrate germ cells and its future clinical translation.
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Affiliation(s)
- Qiaojuan Mei
- Institute of Reproductive Health and Center for Reproductive Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Huiying Li
- Institute of Reproductive Health and Center for Reproductive Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yu Liu
- Institute of Reproductive Health and Center for Reproductive Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaofei Wang
- Institute of Reproductive Health and Center for Reproductive Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Wenpei Xiang
- Institute of Reproductive Health and Center for Reproductive Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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4
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Dobramysl U, Jarsch IK, Inoue Y, Shimo H, Richier B, Gadsby JR, Mason J, Szałapak A, Ioannou PS, Correia GP, Walrant A, Butler R, Hannezo E, Simons BD, Gallop JL. Stochastic combinations of actin regulatory proteins are sufficient to drive filopodia formation. J Cell Biol 2021; 220:e202003052. [PMID: 33740033 PMCID: PMC7980258 DOI: 10.1083/jcb.202003052] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 11/23/2020] [Accepted: 01/12/2021] [Indexed: 11/22/2022] Open
Abstract
Assemblies of actin and its regulators underlie the dynamic morphology of all eukaryotic cells. To understand how actin regulatory proteins work together to generate actin-rich structures such as filopodia, we analyzed the localization of diverse actin regulators within filopodia in Drosophila embryos and in a complementary in vitro system of filopodia-like structures (FLSs). We found that the composition of the regulatory protein complex where actin is incorporated (the filopodial tip complex) is remarkably heterogeneous both in vivo and in vitro. Our data reveal that different pairs of proteins correlate with each other and with actin bundle length, suggesting the presence of functional subcomplexes. This is consistent with a theoretical framework where three or more redundant subcomplexes join the tip complex stochastically, with any two being sufficient to drive filopodia formation. We provide an explanation for the observed heterogeneity and suggest that a mechanism based on multiple components allows stereotypical filopodial dynamics to arise from diverse upstream signaling pathways.
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Affiliation(s)
- Ulrich Dobramysl
- Gurdon Institute, University of Cambridge, Cambridge, UK
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Iris Katharina Jarsch
- Gurdon Institute, University of Cambridge, Cambridge, UK
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Yoshiko Inoue
- Gurdon Institute, University of Cambridge, Cambridge, UK
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Hanae Shimo
- Gurdon Institute, University of Cambridge, Cambridge, UK
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Benjamin Richier
- Gurdon Institute, University of Cambridge, Cambridge, UK
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Jonathan R. Gadsby
- Gurdon Institute, University of Cambridge, Cambridge, UK
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Julia Mason
- Gurdon Institute, University of Cambridge, Cambridge, UK
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Alicja Szałapak
- Gurdon Institute, University of Cambridge, Cambridge, UK
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Pantelis Savvas Ioannou
- Gurdon Institute, University of Cambridge, Cambridge, UK
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | | | - Astrid Walrant
- Gurdon Institute, University of Cambridge, Cambridge, UK
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Richard Butler
- Gurdon Institute, University of Cambridge, Cambridge, UK
| | - Edouard Hannezo
- Gurdon Institute, University of Cambridge, Cambridge, UK
- Institute of Science and Technology Austria, Klosterneuburg, Austria
| | - Benjamin D. Simons
- Gurdon Institute, University of Cambridge, Cambridge, UK
- Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Cambridge, UK
| | - Jennifer L. Gallop
- Gurdon Institute, University of Cambridge, Cambridge, UK
- Department of Biochemistry, University of Cambridge, Cambridge, UK
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5
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Jarsch IK, Gadsby JR, Nuccitelli A, Mason J, Shimo H, Pilloux L, Marzook B, Mulvey CM, Dobramysl U, Bradshaw CR, Lilley KS, Hayward RD, Vaughan TJ, Dobson CL, Gallop JL. A direct role for SNX9 in the biogenesis of filopodia. J Cell Biol 2020; 219:151579. [PMID: 32328641 PMCID: PMC7147113 DOI: 10.1083/jcb.201909178] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 01/24/2020] [Accepted: 01/31/2020] [Indexed: 12/13/2022] Open
Abstract
Filopodia are finger-like actin-rich protrusions that extend from the cell surface and are important for cell-cell communication and pathogen internalization. The small size and transient nature of filopodia combined with shared usage of actin regulators within cells confounds attempts to identify filopodial proteins. Here, we used phage display phenotypic screening to isolate antibodies that alter the actin morphology of filopodia-like structures (FLS) in vitro. We found that all of the antibodies that cause shorter FLS interact with SNX9, an actin regulator that binds phosphoinositides during endocytosis and at invadopodia. In cells, we discover SNX9 at specialized filopodia in Xenopus development and that SNX9 is an endogenous component of filopodia that are hijacked by Chlamydia entry. We show the use of antibody technology to identify proteins used in filopodia-like structures, and a role for SNX9 in filopodia.
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Affiliation(s)
- Iris K Jarsch
- Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Jonathan R Gadsby
- Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Annalisa Nuccitelli
- Antibody Discovery and Protein Engineering, AstraZeneca, Granta Park, Cambridge, UK
| | - Julia Mason
- Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Hanae Shimo
- Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Ludovic Pilloux
- Department of Pathology, University of Cambridge, Cambridge, UK
| | - Bishara Marzook
- Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Claire M Mulvey
- Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Ulrich Dobramysl
- Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Charles R Bradshaw
- Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge, UK
| | - Kathryn S Lilley
- Department of Biochemistry, University of Cambridge, Cambridge, UK
| | | | - Tristan J Vaughan
- Antibody Discovery and Protein Engineering, AstraZeneca, Granta Park, Cambridge, UK
| | - Claire L Dobson
- Antibody Discovery and Protein Engineering, AstraZeneca, Granta Park, Cambridge, UK
| | - Jennifer L Gallop
- Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge, UK
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6
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Lebek NM, Campellone KG. Adding SNX to the mix: SNX9 drives filopodia biogenesis. J Cell Biol 2020; 219:e202002086. [PMID: 32328644 PMCID: PMC7147100 DOI: 10.1083/jcb.202002086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Filopodia are actin-rich protrusions important for sensing and responding to the extracellular environment, but the repertoire of factors required for filopodia formation is only partially understood. Jarsch et al. (2020. J. Cell. Biol. https://doi.org/10.1083/jcb.201909178) combine an in vitro system of filopodia biogenesis with a phage display screen to show that SNX9 drives filopodial assembly.
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Affiliation(s)
| | - Kenneth G. Campellone
- Department of Molecular & Cell Biology and Institute for Systems Genomics, University of Connecticut, Storrs, CT
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7
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Fox HM, Gallop JL. Filopodia-Like Structure Formation from Xenopus Egg Extracts. Cold Spring Harb Protoc 2019; 2019:pdb.prot100545. [PMID: 29208644 DOI: 10.1101/pdb.prot100545] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The actin cytoskeleton comprises many different architectures of filaments, including branched networks, parallel bundles and antiparallel fibers. A current challenge is to elucidate how the diverse array of actin regulators, which controls the growth, assembly and turnover of actin filaments, is used to orchestrate cytoskeletal organization and in turn cell shape and movement. Long observed to assemble at cell membranes, actin in Xenopus egg extracts recapitulates membrane-triggered assembly at specific lipid and membrane environments. The use of Xenopus egg extracts has contributed greatly to identifying how constitutively autoinhibited regulatory pathways are activated, which converge on activation of the Arp2/3 complex. Here we describe a protocol for making parallel actin bundles using Xenopus egg extracts from supernatants prepared by high-speed centrifugation. These filopodia-like actin bundles emanate from clusters of actin regulators that self-assemble at phosphatidylinositol (4,5)-bisphosphate-containing supported lipid bilayers. Forming a plasma membrane-mimicking bilayer on glass allows easy, optimizable, high signal-to-noise microscopy at high spatial and temporal resolution. The use of Xenopus egg extracts yields large quantities of active material that can be flexibly tailored to address specific questions, for example, by dilution, addition of fluorescent proteins, antibodies or protein fragments, immunodepletion, addition of small molecule inhibitors, or biochemical fractionation.
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Affiliation(s)
- Helen M Fox
- Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, Cambridge CB2 1QN, United Kingdom
| | - Jennifer L Gallop
- Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, Cambridge CB2 1QN, United Kingdom
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8
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Janmey PA, Bucki R, Radhakrishnan R. Regulation of actin assembly by PI(4,5)P2 and other inositol phospholipids: An update on possible mechanisms. Biochem Biophys Res Commun 2018; 506:307-314. [PMID: 30139519 DOI: 10.1016/j.bbrc.2018.07.155] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2018] [Revised: 06/21/2018] [Accepted: 07/31/2018] [Indexed: 01/15/2023]
Abstract
Actin cytoskeleton dynamics depend on a tight regulation of actin filament formation from an intracellular pool of monomers, followed by their linkage to each other or to cell membranes, followed by their depolymerization into a fresh pool of actin monomers. The ubiquitous requirement for continuous actin remodeling that is necessary for many cellular functions is orchestrated in large part by actin binding proteins whose affinity for actin is altered by inositol phospholipids, most prominently PI(4,5)P2 (phosphatidylinositol 4,5-bisphosphate). The kinetics of PI(4,5)P2 synthesis and hydrolysis, its lateral distribution within the lipid bilayer, and coincident detection of PI(4,5)P2 and another signal, all play a role in determining when and where a particular PI(4,5)P2-regulated protein is inactivated or activated to exert its effect on the actin cytoskeleton. This review summarizes a range of models that have been developed to explain how PI(4,5)P2 might function in the complex chemical and structural environment of the cell based on a combination of experiment and computational studies.
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Affiliation(s)
- Paul A Janmey
- Department of Physiology, University of Pennsylvania, Philadelphia, PA, USA; Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, PA, USA.
| | - Robert Bucki
- Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, PA, USA; Department of Microbiological and Nanobiomedical Engineering, Medical University of Bialystok, Bialystok, Poland
| | - Ravi Radhakrishnan
- Department of Bioengineering, University of Pennsylvania, Philadelphia, PA, USA
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9
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Daste F, Walrant A, Holst MR, Gadsby JR, Mason J, Lee JE, Brook D, Mettlen M, Larsson E, Lee SF, Lundmark R, Gallop JL. Control of actin polymerization via the coincidence of phosphoinositides and high membrane curvature. J Cell Biol 2017; 216:3745-3765. [PMID: 28923975 PMCID: PMC5674896 DOI: 10.1083/jcb.201704061] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 07/06/2017] [Accepted: 08/04/2017] [Indexed: 12/26/2022] Open
Abstract
How the membrane environment informs when and where actin is polymerized in clathrin-mediated endocytosis is unclear. Daste et al. show that high membrane curvature stimulates PI(3,4)P2 dephosphorylation by INPP4A and that PI(3)P recruits SNX9 in conjunction with both PI(4,5)P2 and high membrane curvature. Furthermore, they find that Lowe syndrome mimics this membrane microenvironment with the aberrant formation of a PI(4,5)P2/PI(3)P intermediate, giving rise to actin comets. The conditional use of actin during clathrin-mediated endocytosis in mammalian cells suggests that the cell controls whether and how actin is used. Using a combination of biochemical reconstitution and mammalian cell culture, we elucidate a mechanism by which the coincidence of PI(4,5)P2 and PI(3)P in a curved vesicle triggers actin polymerization. At clathrin-coated pits, PI(3)P is produced by the INPP4A hydrolysis of PI(3,4)P2, and this is necessary for actin-driven endocytosis. Both Cdc42⋅guanosine triphosphate and SNX9 activate N-WASP–WIP- and Arp2/3-mediated actin nucleation. Membrane curvature, PI(4,5)P2, and PI(3)P signals are needed for SNX9 assembly via its PX–BAR domain, whereas signaling through Cdc42 is activated by PI(4,5)P2 alone. INPP4A activity is stimulated by high membrane curvature and synergizes with SNX9 BAR domain binding in a process we call curvature cascade amplification. We show that the SNX9-driven actin comets that arise on human disease–associated oculocerebrorenal syndrome of Lowe (OCRL) deficiencies are reduced by inhibiting PI(3)P production, suggesting PI(3)P kinase inhibitors as a therapeutic strategy in Lowe syndrome.
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Affiliation(s)
- Frederic Daste
- Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge, England, UK
| | - Astrid Walrant
- Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge, England, UK
| | - Mikkel R Holst
- Integrative Medical Biology, Umeå University, Umeå, Sweden
| | - Jonathan R Gadsby
- Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge, England, UK
| | - Julia Mason
- Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge, England, UK
| | - Ji-Eun Lee
- Department of Chemistry, University of Cambridge, Cambridge, England, UK
| | - Daniel Brook
- Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge, England, UK
| | - Marcel Mettlen
- University of Texas Southwestern Medical Center, Dallas, TX
| | - Elin Larsson
- Integrative Medical Biology, Umeå University, Umeå, Sweden
| | - Steven F Lee
- Department of Chemistry, University of Cambridge, Cambridge, England, UK
| | | | - Jennifer L Gallop
- Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge, Cambridge, England, UK
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10
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Bermudez JG, Chen H, Einstein LC, Good MC. Probing the biology of cell boundary conditions through confinement of Xenopus cell-free cytoplasmic extracts. Genesis 2017; 55. [PMID: 28132422 DOI: 10.1002/dvg.23013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 12/04/2016] [Accepted: 12/05/2016] [Indexed: 11/11/2022]
Abstract
Cell-free cytoplasmic extracts prepared from Xenopus eggs and embryos have for decades provided a biochemical system with which to interrogate complex cell biological processes in vitro. Recently, the application of microfabrication and microfluidic strategies in biology has narrowed the gap between in vitro and in vivo studies by enabling formation of cell-size compartments containing functional cytoplasm. These approaches provide numerous advantages over traditional biochemical experiments performed in a test tube. Most notably, the cell-free cytoplasm is confined using a two- or three-dimensional boundary, which mimics the natural configuration of a cell. This strategy enables characterization of the spatial organization of a cell, and the role that boundaries play in regulating intracellular assembly and function. In this review, we describe the marriage of Xenopus cell-free cytoplasm and confinement technologies to generate synthetic cell-like systems, the recent biological insights they have enabled, and the promise they hold for future scientific discovery.
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Affiliation(s)
- Jessica G Bermudez
- Department of Bioengineering, University of Pennsylvania, 421 Curie Blvd, 1151 BRB II/III, Philadelphia, Pennsylvania, 19104
| | - Hui Chen
- Department of Cell and Developmental Biology, University of Pennsylvania, 421 Curie Blvd, 1151 BRB II/III, Philadelphia, Pennsylvania, 19104
| | - Lily C Einstein
- Department of Cell and Developmental Biology, University of Pennsylvania, 421 Curie Blvd, 1151 BRB II/III, Philadelphia, Pennsylvania, 19104
| | - Matthew C Good
- Department of Bioengineering, University of Pennsylvania, 421 Curie Blvd, 1151 BRB II/III, Philadelphia, Pennsylvania, 19104.,Department of Cell and Developmental Biology, University of Pennsylvania, 421 Curie Blvd, 1151 BRB II/III, Philadelphia, Pennsylvania, 19104
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11
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Migas UM, Quinn MK, McManus JJ. Protein self-assembly following in situ expression in artificial and mammalian cells. Integr Biol (Camb) 2017; 9:444-450. [DOI: 10.1039/c6ib00240d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The importance of in vitro measurements in explaining the mechanisms underlying protein self-assembly in physiologically relevant conditions has been demonstrated in solution and in artificial and mammalian cells.
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12
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Watson JR, Fox HM, Nietlispach D, Gallop JL, Owen D, Mott HR. Investigation of the Interaction between Cdc42 and Its Effector TOCA1: HANDOVER OF Cdc42 TO THE ACTIN REGULATOR N-WASP IS FACILITATED BY DIFFERENTIAL BINDING AFFINITIES. J Biol Chem 2016; 291:13875-90. [PMID: 27129201 PMCID: PMC4919469 DOI: 10.1074/jbc.m116.724294] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Indexed: 11/23/2022] Open
Abstract
Transducer of Cdc42-dependent actin assembly protein 1 (TOCA1) is an effector of the Rho family small G protein Cdc42. It contains a membrane-deforming F-BAR domain as well as a Src homology 3 (SH3) domain and a G protein-binding homology region 1 (HR1) domain. TOCA1 binding to Cdc42 leads to actin rearrangements, which are thought to be involved in processes such as endocytosis, filopodia formation, and cell migration. We have solved the structure of the HR1 domain of TOCA1, providing the first structural data for this protein. We have found that the TOCA1 HR1, like the closely related CIP4 HR1, has interesting structural features that are not observed in other HR1 domains. We have also investigated the binding of the TOCA HR1 domain to Cdc42 and the potential ternary complex between Cdc42 and the G protein-binding regions of TOCA1 and a member of the Wiskott-Aldrich syndrome protein family, N-WASP. TOCA1 binds Cdc42 with micromolar affinity, in contrast to the nanomolar affinity of the N-WASP G protein-binding region for Cdc42. NMR experiments show that the Cdc42-binding domain from N-WASP is able to displace TOCA1 HR1 from Cdc42, whereas the N-WASP domain but not the TOCA1 HR1 domain inhibits actin polymerization. This suggests that TOCA1 binding to Cdc42 is an early step in the Cdc42-dependent pathways that govern actin dynamics, and the differential binding affinities of the effectors facilitate a handover from TOCA1 to N-WASP, which can then drive recruitment of the actin-modifying machinery.
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Affiliation(s)
- Joanna R Watson
- From the Department of Biochemistry, 80 Tennis Court Road, University of Cambridge, Cambridge CB2 1GA and
| | - Helen M Fox
- From the Department of Biochemistry, 80 Tennis Court Road, University of Cambridge, Cambridge CB2 1GA and the Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, United Kingdom
| | - Daniel Nietlispach
- From the Department of Biochemistry, 80 Tennis Court Road, University of Cambridge, Cambridge CB2 1GA and
| | - Jennifer L Gallop
- From the Department of Biochemistry, 80 Tennis Court Road, University of Cambridge, Cambridge CB2 1GA and the Wellcome Trust/Cancer Research UK Gurdon Institute, University of Cambridge, Cambridge CB2 1QN, United Kingdom
| | - Darerca Owen
- From the Department of Biochemistry, 80 Tennis Court Road, University of Cambridge, Cambridge CB2 1GA and
| | - Helen R Mott
- From the Department of Biochemistry, 80 Tennis Court Road, University of Cambridge, Cambridge CB2 1GA and
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