1
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Kushwaha S, Mallik B, Bisht A, Mushtaq Z, Pippadpally S, Chandra N, Das S, Ratnaparkhi G, Kumar V. dAsap regulates cellular protrusions via an Arf6-dependent actin regulatory pathway in S2R+ cells. FEBS Lett 2024. [PMID: 38862211 DOI: 10.1002/1873-3468.14954] [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: 01/16/2024] [Revised: 05/05/2024] [Accepted: 05/10/2024] [Indexed: 06/13/2024]
Abstract
Membrane protrusions are fundamental to cellular functions like migration, adhesion, and communication and depend upon dynamic reorganization of the cytoskeleton. GAP-dependent GTP hydrolysis of Arf proteins regulates actin-dependent membrane remodeling. Here, we show that dAsap regulates membrane protrusions in S2R+ cells by a mechanism that critically relies on its ArfGAP domain and relocalization of actin regulators, SCAR, and Ena. While our data reinforce the preference of dAsap for Arf1 GTP hydrolysis in vitro, we demonstrate that induction of membrane protrusions in S2R+ cells depends on Arf6 inactivation. This study furthers our understanding of how dAsap-dependent GTP hydrolysis maintains a balance between active and inactive states of Arf6 to regulate cell shape.
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Affiliation(s)
- Shikha Kushwaha
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Bhopal, India
| | - Bhagaban Mallik
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Bhopal, India
| | - Anjali Bisht
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Bhopal, India
| | - Zeeshan Mushtaq
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Bhopal, India
| | - Srikanth Pippadpally
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Bhopal, India
| | - Nitika Chandra
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Bhopal, India
| | - Subhradip Das
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Pune, India
| | - Girish Ratnaparkhi
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Pune, India
| | - Vimlesh Kumar
- Department of Biological Sciences, Indian Institute of Science Education and Research (IISER) Bhopal, India
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2
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Banerjee DS, Freedman SL, Murrell MP, Banerjee S. Growth-induced collective bending and kinetic trapping of cytoskeletal filaments. Cytoskeleton (Hoboken) 2024. [PMID: 38775207 DOI: 10.1002/cm.21877] [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: 01/09/2024] [Revised: 04/30/2024] [Accepted: 05/06/2024] [Indexed: 06/04/2024]
Abstract
Growth and turnover of actin filaments play a crucial role in the construction and maintenance of actin networks within cells. Actin filament growth occurs within limited space and finite subunit resources in the actin cortex. To understand how filament growth shapes the emergent architecture of actin networks, we developed a minimal agent-based model coupling filament mechanics and growth in a limiting subunit pool. We find that rapid filament growth induces kinetic trapping of highly bent actin filaments. Such collective bending patterns are long-lived, organized around nematic defects, and arise from competition between filament polymerization and bending elasticity. The stability of nematic defects and the extent of kinetic trapping are amplified by an increase in the abundance of the actin pool and by crosslinking the network. These findings suggest that kinetic trapping is a robust consequence of growth in crowded environments, providing a route to program shape memory in actin networks.
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Affiliation(s)
- Deb Sankar Banerjee
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
- James Franck Institute, University of Chicago, Chicago, Illinois, USA
| | | | - Michael P Murrell
- Department of Biomedical Engineering, Yale University, New Haven, Connecticut, USA
- Systems Biology Institute, West Haven, Connecticut, USA
- Department of Physics, Yale University, New Haven, Connecticut, USA
| | - Shiladitya Banerjee
- Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania, USA
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3
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Gu Q, An Y, Xu M, Huang X, Chen X, Li X, Shan H, Zhang M. Disulfidptosis, A Novel Cell Death Pathway: Molecular Landscape and Therapeutic Implications. Aging Dis 2024:AD.2024.0083. [PMID: 38739940 DOI: 10.14336/ad.2024.0083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2024] [Accepted: 05/02/2024] [Indexed: 05/16/2024] Open
Abstract
Programmed cell death is pivotal for several physiological processes, including immune defense. Further, it has been implicated in the pathogenesis of developmental disorders and the onset of numerous diseases. Multiple modes of programmed cell death, including apoptosis, pyroptosis, necroptosis, and ferroptosis, have been identified, each with their own unique characteristics and biological implications. In February 2023, Liu Xiaoguang and his team discovered "disulfidptosis," a novel pathway of programmed cell death. Their findings demonstrated that disulfidptosis is triggered in glucose-starved cells exhibiting high expression of a protein called SLC7A11. Furthermore, disulfidptosis is marked by a drastic imbalance in the NADPH/NADP+ ratio and the abnormal accumulation of disulfides like cystine. These changes ultimately lead to the destabilization of the F-actin network, causing cell death. Given that high SLC7A11 expression is a key feature of certain cancers, these findings indicate that disulfidptosis could serve as the basis of innovative anti-cancer therapies. Hence, this review delves into the discovery of disulfidptosis, its underlying molecular mechanisms and metabolic regulation, and its prospective applications in disease treatment.
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Affiliation(s)
- Qiuyang Gu
- Institute of Forensic Sciences, Suzhou Medical College, Soochow University, Suzhou, China
| | - Yumei An
- Institute of Forensic Sciences, Suzhou Medical College, Soochow University, Suzhou, China
| | - Mingyuan Xu
- Institute of Forensic Sciences, Suzhou Medical College, Soochow University, Suzhou, China
| | - Xinqi Huang
- Institute of Forensic Sciences, Suzhou Medical College, Soochow University, Suzhou, China
| | - Xueshi Chen
- Institute of Forensic Sciences, Suzhou Medical College, Soochow University, Suzhou, China
| | - Xianzhe Li
- Institute of Forensic Sciences, Suzhou Medical College, Soochow University, Suzhou, China
| | - Haiyan Shan
- Department of Obstetrics and Gynecology, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou, China
| | - Mingyang Zhang
- Institute of Forensic Sciences, Suzhou Medical College, Soochow University, Suzhou, China
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4
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Liu T, Cao L, Mladenov M, Jegou A, Way M, Moores CA. Cortactin stabilizes actin branches by bridging activated Arp2/3 to its nucleated actin filament. Nat Struct Mol Biol 2024; 31:801-809. [PMID: 38267598 PMCID: PMC11102864 DOI: 10.1038/s41594-023-01205-2] [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: 07/25/2023] [Accepted: 12/18/2023] [Indexed: 01/26/2024]
Abstract
Regulation of the assembly and turnover of branched actin filament networks nucleated by the Arp2/3 complex is essential during many cellular processes, including cell migration and membrane trafficking. Cortactin is important for actin branch stabilization, but the mechanism by which this occurs is unclear. Given this, we determined the structure of vertebrate cortactin-stabilized Arp2/3 actin branches using cryogenic electron microscopy. We find that cortactin interacts with the new daughter filament nucleated by the Arp2/3 complex at the branch site, rather than the initial mother actin filament. Cortactin preferentially binds activated Arp3. It also stabilizes the F-actin-like interface of activated Arp3 with the first actin subunit of the new filament, and its central repeats extend along successive daughter-filament subunits. The preference of cortactin for activated Arp3 explains its retention at the actin branch and accounts for its synergy with other nucleation-promoting factors in regulating branched actin network dynamics.
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Affiliation(s)
- Tianyang Liu
- Institute of Structural and Molecular Biology, Birkbeck College, London, UK
| | - Luyan Cao
- The Francis Crick Institute, London, UK
| | | | - Antoine Jegou
- Université Paris Cité, CNRS, Institut Jacques Monod, Paris, France
| | - Michael Way
- The Francis Crick Institute, London, UK.
- Department of Infectious Disease, Imperial College, London, UK.
| | - Carolyn A Moores
- Institute of Structural and Molecular Biology, Birkbeck College, London, UK.
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5
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Advedissian T, Frémont S, Echard A. Cytokinetic abscission requires actin-dependent microtubule severing. Nat Commun 2024; 15:1949. [PMID: 38431632 PMCID: PMC10908825 DOI: 10.1038/s41467-024-46062-9] [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: 05/22/2023] [Accepted: 02/09/2024] [Indexed: 03/05/2024] Open
Abstract
Cell division is completed by the abscission of the intercellular bridge connecting the daughter cells. Abscission requires the polymerization of an ESCRT-III cone close to the midbody to both recruit the microtubule severing enzyme spastin and scission the plasma membrane. Here, we found that the microtubule and the membrane cuts are two separate events that are regulated differently. Using HeLa cells, we uncovered that the F-actin disassembling protein Cofilin-1 controls the disappearance of a transient pool of branched F-actin which is precisely assembled at the tip of the ESCRT-III cone shortly before the microtubule cut. Functionally, Cofilin-1 and Arp2/3-mediated branched F-actin favor abscission by promoting local severing of the microtubules but do not participate later in the membrane scission event. Mechanistically, we propose that branched F-actin functions as a physical barrier that limits ESCRT-III cone elongation and thereby favors stable spastin recruitment. Our work thus reveals that F-actin controls the timely and local disassembly of microtubules required for cytokinetic abscission.
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Affiliation(s)
- Tamara Advedissian
- Institut Pasteur, Université Paris Cité, CNRS UMR3691, Membrane Traffic and Cell Division Unit, 25-28 rue du Dr Roux, F-75015, Paris, France
| | - Stéphane Frémont
- Institut Pasteur, Université Paris Cité, CNRS UMR3691, Membrane Traffic and Cell Division Unit, 25-28 rue du Dr Roux, F-75015, Paris, France
| | - Arnaud Echard
- Institut Pasteur, Université Paris Cité, CNRS UMR3691, Membrane Traffic and Cell Division Unit, 25-28 rue du Dr Roux, F-75015, Paris, France.
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6
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Kotah JM, Kater MSJ, Brosens N, Lesuis SL, Tandari R, Blok TM, Marchetto L, Yusaf E, Koopmans FTW, Smit AB, Lucassen PJ, Krugers HJ, Verheijen MHG, Korosi A. Early-life stress and amyloidosis in mice share pathogenic pathways involving synaptic mitochondria and lipid metabolism. Alzheimers Dement 2024; 20:1637-1655. [PMID: 38055782 PMCID: PMC10984508 DOI: 10.1002/alz.13569] [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: 05/30/2023] [Revised: 11/07/2023] [Accepted: 11/09/2023] [Indexed: 12/08/2023]
Abstract
INTRODUCTION Early-life stress (ES) increases the risk for Alzheimer's disease (AD). We and others have shown that ES aggravates amyloid-beta (Aβ) pathology and promotes cognitive dysfunction in APP/PS1 mice, but underlying mechanisms remain unclear. METHODS We studied how ES affects the hippocampal synaptic proteome in wild-type (WT) and APP/PS1 mice at early and late pathological stages, and validated hits using electron microscopy and immunofluorescence. RESULTS The hippocampal synaptosomes of both ES-exposed WT and early-stage APP/PS1 mice showed a relative decrease in actin dynamics-related proteins and a relative increase in mitochondrial proteins. ES had minimal effects on older WT mice, while strongly affecting the synaptic proteome of advanced stage APP/PS1 mice, particularly the expression of astrocytic and mitochondrial proteins. DISCUSSION Our data show that ES and amyloidosis share pathogenic pathways involving synaptic mitochondrial dysfunction and lipid metabolism, which may underlie the observed impact of ES on the trajectory of AD.
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Affiliation(s)
- Janssen M. Kotah
- Brain Plasticity GroupSwammerdam Institute for Life Sciences – Center for NeuroscienceUniversity of AmsterdamAmsterdamThe Netherlands
| | - Mandy S. J. Kater
- Department of Molecular and Cellular NeurobiologyCenter for Neurogenomics and Cognitive ResearchAmsterdam NeuroscienceVrije Universiteit AmsterdamAmsterdamThe Netherlands
| | - Niek Brosens
- Brain Plasticity GroupSwammerdam Institute for Life Sciences – Center for NeuroscienceUniversity of AmsterdamAmsterdamThe Netherlands
| | - Sylvie L. Lesuis
- Brain Plasticity GroupSwammerdam Institute for Life Sciences – Center for NeuroscienceUniversity of AmsterdamAmsterdamThe Netherlands
| | - Roberta Tandari
- Brain Plasticity GroupSwammerdam Institute for Life Sciences – Center for NeuroscienceUniversity of AmsterdamAmsterdamThe Netherlands
| | - Thomas M. Blok
- Department of Molecular and Cellular NeurobiologyCenter for Neurogenomics and Cognitive ResearchAmsterdam NeuroscienceVrije Universiteit AmsterdamAmsterdamThe Netherlands
| | - Luca Marchetto
- Brain Plasticity GroupSwammerdam Institute for Life Sciences – Center for NeuroscienceUniversity of AmsterdamAmsterdamThe Netherlands
| | - Ella Yusaf
- Brain Plasticity GroupSwammerdam Institute for Life Sciences – Center for NeuroscienceUniversity of AmsterdamAmsterdamThe Netherlands
| | - Frank T. W. Koopmans
- Department of Molecular and Cellular NeurobiologyCenter for Neurogenomics and Cognitive ResearchAmsterdam NeuroscienceVrije Universiteit AmsterdamAmsterdamThe Netherlands
| | - August B. Smit
- Department of Molecular and Cellular NeurobiologyCenter for Neurogenomics and Cognitive ResearchAmsterdam NeuroscienceVrije Universiteit AmsterdamAmsterdamThe Netherlands
| | - Paul J. Lucassen
- Brain Plasticity GroupSwammerdam Institute for Life Sciences – Center for NeuroscienceUniversity of AmsterdamAmsterdamThe Netherlands
| | - Harm J. Krugers
- Brain Plasticity GroupSwammerdam Institute for Life Sciences – Center for NeuroscienceUniversity of AmsterdamAmsterdamThe Netherlands
| | - Mark H. G. Verheijen
- Department of Molecular and Cellular NeurobiologyCenter for Neurogenomics and Cognitive ResearchAmsterdam NeuroscienceVrije Universiteit AmsterdamAmsterdamThe Netherlands
| | - Aniko Korosi
- Brain Plasticity GroupSwammerdam Institute for Life Sciences – Center for NeuroscienceUniversity of AmsterdamAmsterdamThe Netherlands
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7
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Akompong SK, Li Y, Gong W, Ye L, Liu J. Recently reported cell migration inhibitors: Opportunities and challenges for antimetastatic agents. Drug Discov Today 2024; 29:103906. [PMID: 38309689 DOI: 10.1016/j.drudis.2024.103906] [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] [Received: 09/25/2023] [Revised: 01/17/2024] [Accepted: 01/25/2024] [Indexed: 02/05/2024]
Abstract
Antimetastatic agents are highly desirable for cancer treatment because of the severe medical challenges and high mortality resulting from tumor metastasis. Having demonstrated antimetastatic effects in numerous in vitro and in vivo studies, migration inhibitors present significant opportunities for developing a new class of anticancer drugs. To provide a useful overview on the latest research in migration inhibitors, this article first discusses their therapeutic significance, targetable proteins, and developmental avenues. Subsequently it reviews over 20 representative migration inhibitors reported in recent journals in terms of their inhibitory mechanism, potency, and potential clinical utility. The relevance of the target proteins to cellular migratory function is focused on as it is crucial for assessing the overall efficacy of the inhibitors.
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Affiliation(s)
- Samuel K Akompong
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan 430081, China
| | - Yang Li
- Zhongnan Hospital of Wuhan University, Wuhan 430071, China
| | - Wenxue Gong
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan 430081, China
| | - Long Ye
- School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan 430081, China.
| | - Jinping Liu
- Zhongnan Hospital of Wuhan University, Wuhan 430071, China.
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8
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Banerjee DS, Freedman SL, Murrell MP, Banerjee S. Growth-induced collective bending and kinetic trapping of cytoskeletal filaments. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.01.09.574885. [PMID: 38260433 PMCID: PMC10802417 DOI: 10.1101/2024.01.09.574885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2024]
Abstract
Growth and turnover of actin filaments play a crucial role in the construction and maintenance of actin networks within cells. Actin filament growth occurs within limited space and finite subunit resources in the actin cortex. To understand how filament growth shapes the emergent architecture of actin networks, we developed a minimal agent-based model coupling filament mechanics and growth in a limiting subunit pool. We find that rapid filament growth induces kinetic trapping of highly bent actin filaments. Such collective bending patterns are long-lived, organized around nematic defects, and arises from competition between filament polymerization and bending elasticity. The stability of nematic defects and the extent of kinetic trapping are amplified by an increase in the abundance of the actin pool and by crosslinking the network. These findings suggest that kinetic trapping is a robust consequence of growth in crowded environments, providing a route to program shape memory in actin networks.
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Affiliation(s)
- Deb Sankar Banerjee
- Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213, USA
- James Franck Institute, University of Chicago, Chicago, IL 60637, USA
| | | | - Michael P Murrell
- Department of Biomedical Engineering, Yale University, 10 Hillhouse Avenue, New Haven, CT, USA
- Systems Biology Institute, 850 West Campus Drive, West Haven, CT, USA
- Department of Physics, Yale University, 217 Prospect Street, New Haven, CT, USA
| | - Shiladitya Banerjee
- Department of Physics, Carnegie Mellon University, Pittsburgh, PA 15213, USA
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9
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Stromberg KA, Spain T, Tomlin SA, Powell J, Amarillo KD, Schroeder CM. Evolutionary diversification reveals distinct somatic versus germline cytoskeletal functions of the Arp2 branched actin nucleator protein. Curr Biol 2023; 33:5326-5339.e7. [PMID: 37977138 PMCID: PMC10785674 DOI: 10.1016/j.cub.2023.10.055] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 09/18/2023] [Accepted: 10/25/2023] [Indexed: 11/19/2023]
Abstract
Branched actin networks are critical in many cellular processes, including cell motility and division. Arp2, a protein within the seven-membered Arp2/3 complex, is responsible for generating branched actin. Given its essential roles, Arp2 evolves under stringent sequence conservation throughout eukaryotic evolution. We unexpectedly discovered recurrent evolutionary diversification of Arp2 in Drosophila, yielding independently arising paralogs Arp2D in obscura species and Arp2D2 in montium species. Both paralogs are unusually testis-enriched in expression relative to Arp2. We investigated whether their sequence divergence from canonical Arp2 led to functional specialization by replacing Arp2 in D. melanogaster with either Arp2D or Arp2D2. Despite their divergence, we surprisingly found that both complement Arp2's essential function in somatic tissue, suggesting they have preserved the ability to polymerize branched actin even in a non-native species. However, we found that Arp2D- and Arp2D2-expressing males display defects throughout sperm development, with Arp2D resulting in more pronounced deficiencies and subfertility, suggesting the Arp2 paralogs are cross-species incompatible in the testis. We focused on Arp2D and pinpointed two highly diverged structural regions-the D-loop and C terminus-and found that they contribute to germline defects in D. melanogaster sperm development. However, while the Arp2D C terminus is suboptimal in the D. melanogaster testis, it is essential for Arp2D somatic function. Testis cytology of the paralogs' native species revealed striking differences in germline actin structures, indicating unique cytoskeletal requirements. Our findings suggest canonical Arp2 function differs between somatic versus germline contexts, and Arp2 paralogs may have recurrently evolved for species-specialized actin branching in the testis.
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Affiliation(s)
- Kaitlin A Stromberg
- Department of Pharmacology, UT Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390, USA
| | - Tristan Spain
- Department of Pharmacology, UT Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390, USA
| | - Sarah A Tomlin
- Division of Basic Sciences, Fred Hutchinson Cancer Center, 1100 Fairview Avenue North, Seattle, WA 98109, USA; Howard Hughes Medical Institute, Fred Hutchinson Cancer Center, 1100 Fairview Avenue North, Seattle, WA 98109, USA
| | - Jordan Powell
- Department of Pharmacology, UT Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390, USA
| | - Kristen Dominique Amarillo
- Department of Pharmacology, UT Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390, USA
| | - Courtney M Schroeder
- Department of Pharmacology, UT Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390, USA.
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10
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Fregoso FE, Boczkowska M, Rebowski G, Carman PJ, van Eeuwen T, Dominguez R. Mechanism of synergistic activation of Arp2/3 complex by cortactin and WASP-family proteins. Nat Commun 2023; 14:6894. [PMID: 37898612 PMCID: PMC10613254 DOI: 10.1038/s41467-023-42229-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 09/29/2023] [Indexed: 10/30/2023] Open
Abstract
Cortactin coactivates Arp2/3 complex synergistically with WASP-family nucleation-promoting factors (NPFs) and stabilizes branched networks by linking Arp2/3 complex to F-actin. It is poorly understood how cortactin performs these functions. We describe the 2.89 Å resolution cryo-EM structure of cortactin's N-terminal domain (Cort1-76) bound to Arp2/3 complex. Cortactin binds Arp2/3 complex through an inverted Acidic domain (D20-V29), which targets the same site on Arp3 as the Acidic domain of NPFs but with opposite polarity. Sequences N- and C-terminal to cortactin's Acidic domain do not increase its affinity for Arp2/3 complex but contribute toward coactivation with NPFs. Coactivation further increases with NPF dimerization and for longer cortactin constructs with stronger binding to F-actin. The results suggest that cortactin contributes to Arp2/3 complex coactivation with NPFs in two ways, by helping recruit the complex to F-actin and by stabilizing the short-pitch (active) conformation, which are both byproducts of cortactin's core function in branch stabilization.
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Affiliation(s)
- Fred E Fregoso
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Malgorzata Boczkowska
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Grzegorz Rebowski
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Peter J Carman
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Trevor van Eeuwen
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY, 10065, USA
| | - Roberto Dominguez
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
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11
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Asante-Asamani E, Dalton M, Brazill D, Strychalski W. Modeling the dynamics of actin and myosin during bleb stabilization. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.10.26.564082. [PMID: 37961169 PMCID: PMC10634845 DOI: 10.1101/2023.10.26.564082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2023]
Abstract
The actin cortex is very dynamic during migration of eukaryotes. In cells that use blebs as leading-edge protrusions, the cortex reforms beneath the cell membrane (bleb cortex) and completely disassembles at the site of bleb initiation. Remnants of the actin cortex at the site of bleb nucleation are referred to as the actin scar. We refer to the combined process of cortex reformation along with the degradation of the actin scar during bleb-based cell migration as bleb stabilization. The molecular factors that regulate the dynamic reorganization of the cortex are not fully understood. Myosin motor protein activity has been shown to be necessary for blebbing, with its major role associated with pressure generation to drive bleb expansion. Here, we examine the role of myosin in regulating cortex dynamics during bleb stabilization. Analysis of microscopy data from protein localization experiments in Dictyostelium discoideum cells reveals a rapid formation of the bleb's cortex with a delay in myosin accumulation. In the degrading actin scar, myosin is observed to accumulate before active degradation of the cortex begins. Through a combination of mathematical modeling and data fitting, we identify that myosin helps regulate the equilibrium concentration of actin in the bleb cortex during its reformation by increasing its dissasembly rate. Our modeling and analysis also suggests that cortex degradation is driven primarily by an exponential decrease in actin assembly rate rather than increased myosin activity. We attribute the decrease in actin assembly to the separation of the cell membrane from the cortex after bleb nucleation.
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Affiliation(s)
| | - Mackenzie Dalton
- Department of Mathematics, Clarkson University, Clarkson, Potsdam, NY 13699
| | | | - Wanda Strychalski
- Department of Mathematics, Applied Mathematics, and Statistics, Case Western Reserve University, Cleveland, OH 44106
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12
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Heron R, Amato C, Wood W, Davidson AJ. Understanding the diversity and dynamics of in vivo efferocytosis: Insights from the fly embryo. Immunol Rev 2023; 319:27-44. [PMID: 37589239 PMCID: PMC10952863 DOI: 10.1111/imr.13266] [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: 04/03/2023] [Accepted: 07/18/2023] [Indexed: 08/18/2023]
Abstract
The clearance of dead and dying cells, termed efferocytosis, is a rapid and efficient process and one that is critical for organismal health. The extraordinary speed and efficiency with which dead cells are detected and engulfed by immune cells within tissues presents a challenge to researchers who wish to unravel this fascinating process, since these fleeting moments of uptake are almost impossible to catch in vivo. In recent years, the fruit fly (Drosophila melanogaster) embryo has emerged as a powerful model to circumvent this problem. With its abundance of dying cells, specialist phagocytes and relative ease of live imaging, the humble fly embryo provides a unique opportunity to catch and study the moment of cell engulfment in real-time within a living animal. In this review, we explore the recent advances that have come from studies in the fly, and how live imaging and genetics have revealed a previously unappreciated level of diversity in the efferocytic program. A variety of efferocytic strategies across the phagocytic cell population ensure efficient and rapid clearance of corpses wherever death is encountered within the varied and complex setting of a multicellular living organism.
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Affiliation(s)
- Rosalind Heron
- Institute for Regeneration and RepairUniversity of EdinburghEdinburghUK
| | - Clelia Amato
- Institute for Regeneration and RepairUniversity of EdinburghEdinburghUK
| | - Will Wood
- Institute for Regeneration and RepairUniversity of EdinburghEdinburghUK
| | - Andrew J. Davidson
- Institute for Regeneration and RepairUniversity of EdinburghEdinburghUK
- School of Cancer SciencesWolfson Wohl Cancer Research Centre, University of GlasgowGlasgowUK
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13
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Dobson L, Barrell WB, Seraj Z, Lynham S, Wu SY, Krause M, Liu KJ. GSK3 and lamellipodin balance lamellipodial protrusions and focal adhesion maturation in mouse neural crest migration. Cell Rep 2023; 42:113030. [PMID: 37632751 DOI: 10.1016/j.celrep.2023.113030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 07/06/2023] [Accepted: 08/09/2023] [Indexed: 08/28/2023] Open
Abstract
Neural crest cells are multipotent cells that delaminate from the neuroepithelium, migrating throughout the embryo. Aberrant migration causes developmental defects. Animal models are improving our understanding of neural crest anomalies, but in vivo migration behaviors are poorly understood. Here, we demonstrate that murine neural crest cells display actin-based lamellipodia and filopodia in vivo. Using neural crest-specific knockouts or inhibitors, we show that the serine-threonine kinase glycogen synthase kinase-3 (GSK3) and the cytoskeletal regulator lamellipodin (Lpd) are required for lamellipodia formation while preventing focal adhesion maturation. Lpd is a substrate of GSK3, and phosphorylation of Lpd favors interactions with the Scar/WAVE complex (lamellipodia formation) at the expense of VASP and Mena interactions (adhesion maturation and filopodia formation). This improved understanding of cytoskeletal regulation in mammalian neural crest migration has general implications for neural crest anomalies and cancer.
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Affiliation(s)
- Lisa Dobson
- Centre for Craniofacial and Regenerative Biology, King's College London, London SE1 9RT, UK; Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, UK
| | - William B Barrell
- Centre for Craniofacial and Regenerative Biology, King's College London, London SE1 9RT, UK; Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, UK
| | - Zahra Seraj
- Centre for Craniofacial and Regenerative Biology, King's College London, London SE1 9RT, UK
| | - Steven Lynham
- Centre for Excellence for Mass Spectrometry, King's College London, London SE5 9NU, UK
| | - Sheng-Yuan Wu
- Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, UK
| | - Matthias Krause
- Randall Centre for Cell and Molecular Biophysics, King's College London, London SE1 1UL, UK.
| | - Karen J Liu
- Centre for Craniofacial and Regenerative Biology, King's College London, London SE1 9RT, UK.
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14
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Le Chua X, Tong CS, Xǔ XJ, Su M, Xiao S, Wu X, Wu M. Competition and Synergy of Arp2/3 and Formins in Nucleating Actin Waves. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.13.557508. [PMID: 37745345 PMCID: PMC10515902 DOI: 10.1101/2023.09.13.557508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
The assembly and disassembly of actin filaments and their regulatory proteins are crucial for maintaining cell structure or changing physiological state. However, because of the tremendous global impact of actin on diverse cellular processes, dissecting the specific role of actin regulatory proteins remains challenging. In this study, we employ actin waves that propagate on the cortex of mast cell to investigate the interplay between formins and the Arp2/3 complex in the nucleating and turnover of cortical actin. Our findings reveal that the recruitment of FMNL1 and mDia3 precedes the Arp2/3 complex in cortical actin waves. Membrane and GTPase-interaction can drive oscillations of FMNL1 in an actin-dependent manner, but active Cdc42 waves or constitutively-active FMNL1 mutant can form without actin waves. In addition to the apparent coordinated assembly of formins and Arp2/3, we further reveal their antagonism, where inhibition of Arp2/3 complex by CK-666 led to a transient increase in the recruitment of formins and actin polymerization. Our analysis suggest that the antagonism could not be explained for the competition between FMNL1 and Arp2/3 for monomeric actin. Rather, it is regulated by a limited pool of their common upstream regulator, Cdc42, whose level is negatively regulated by Arp2/3. Collectively, our study highlights the multifaceted interactions, cooperative or competitive, between formins and Arp2/3 complex, in the intricate and dynamic control of actin cytoskeletal network.
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Affiliation(s)
- Xiang Le Chua
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA
- Department of Biological Sciences, Centre for Bioimaging Sciences, Singapore 117557
| | - Chee San Tong
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA
- Department of Biological Sciences, Centre for Bioimaging Sciences, Singapore 117557
| | - X J Xǔ
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA
- Department of Physics, Yale University, New Haven, CT 06511, USA
| | - Maohan Su
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA
- Department of Biological Sciences, Centre for Bioimaging Sciences, Singapore 117557
- Mechanobiology Institute, National University of Singapore, Singapore 117411
| | - Shengping Xiao
- Department of Biological Sciences, Centre for Bioimaging Sciences, Singapore 117557
| | - Xudong Wu
- School of Life Sciences, Westlake University, Hangzhou, China 310024
| | - Min Wu
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510, USA
- Department of Biological Sciences, Centre for Bioimaging Sciences, Singapore 117557
- Department of Physics, Yale University, New Haven, CT 06511, USA
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15
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van Eeuwen T, Boczkowska M, Rebowski G, Carman PJ, Fregoso FE, Dominguez R. Transition State of Arp2/3 Complex Activation by Actin-Bound Dimeric Nucleation-Promoting Factor. Proc Natl Acad Sci U S A 2023; 120:e2306165120. [PMID: 37549294 PMCID: PMC10434305 DOI: 10.1073/pnas.2306165120] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2023] [Accepted: 07/03/2023] [Indexed: 08/09/2023] Open
Abstract
Arp2/3 complex generates branched actin networks that drive fundamental processes such as cell motility and cytokinesis. The complex comprises seven proteins, including actin-related proteins (Arps) 2 and 3 and five scaffolding proteins (ArpC1-ArpC5) that mediate interactions with a pre-existing (mother) actin filament at the branch junction. Arp2/3 complex exists in two main conformations, inactive with the Arps interacting end-to-end and active with the Arps interacting side-by-side like subunits of the short-pitch helix of the actin filament. Several cofactors drive the transition toward the active state, including ATP binding to the Arps, WASP-family nucleation-promoting factors (NPFs), actin monomers, and binding of Arp2/3 complex to the mother filament. The precise contribution of each cofactor to activation is poorly understood. We report the 3.32-Å resolution cryo-electron microscopy structure of a transition state of Arp2/3 complex activation with bound constitutively dimeric NPF. Arp2/3 complex-binding region of the NPF N-WASP was fused C-terminally to the α and β subunits of the CapZ heterodimer. One arm of the NPF dimer binds Arp2 and the other binds actin and Arp3. The conformation of the complex is intermediate between those of inactive and active Arp2/3 complex. Arp2, Arp3, and actin also adopt intermediate conformations between monomeric (G-actin) and filamentous (F-actin) states, but only actin hydrolyzes ATP. In solution, the transition complex is kinetically shifted toward the short-pitch conformation and has higher affinity for F-actin than inactive Arp2/3 complex. The results reveal how all the activating cofactors contribute in a coordinated manner toward Arp2/3 complex activation.
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Affiliation(s)
- Trevor van Eeuwen
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA19104
| | - Malgorzata Boczkowska
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA19104
| | - Grzegorz Rebowski
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA19104
| | - Peter J. Carman
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA19104
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA19104
| | - Fred E. Fregoso
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA19104
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA19104
| | - Roberto Dominguez
- Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA19104
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA19104
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16
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Sadhu RK, Iglič A, Gov NS. A minimal cell model for lamellipodia-based cellular dynamics and migration. J Cell Sci 2023; 136:jcs260744. [PMID: 37497740 DOI: 10.1242/jcs.260744] [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: 07/28/2023] Open
Abstract
One ubiquitous cellular structure for performing various tasks, such as spreading and migration over external surfaces, is the sheet-like protrusion called a lamellipodium, which propels the leading edge of the cell. Despite the detailed knowledge about the many components of this cellular structure, it is not yet fully understood how these components self-organize spatiotemporally to form lamellipodia. We review here recent theoretical works where we have demonstrated that membrane-bound protein complexes that have intrinsic curvature and recruit the protrusive forces of the cytoskeleton result in a simple, yet highly robust, organizing feedback mechanism that organizes the cytoskeleton and the membrane. This self-organization mechanism accounts for the formation of flat lamellipodia at the leading edge of cells spreading over adhesive substrates, allowing for the emergence of a polarized, motile 'minimal cell' model. The same mechanism describes how lamellipodia organize to drive robust engulfment of particles during phagocytosis and explains in simple physical terms the spreading and migration of cells over fibers and other curved surfaces. This Review highlights that despite the complexity of cellular composition, there might be simple general physical principles that are utilized by the cell to drive cellular shape dynamics.
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Affiliation(s)
- Raj Kumar Sadhu
- Institut Curie, PSL Research University, CNRS, UMR 168, Paris 75005, France
| | - Aleš Iglič
- Laboratory of Physics, Faculty of Electrical Engineering, University of Ljubljana, SI-1000 Ljubljana, Slovenia
| | - Nir S Gov
- Department of Chemical and Biological Physics, Weizmann Institute of Science, Rehovot 7610001, Israel
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17
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Murali A, Sarkar RR. Mechano-immunology in microgravity. LIFE SCIENCES IN SPACE RESEARCH 2023; 37:50-64. [PMID: 37087179 DOI: 10.1016/j.lssr.2023.03.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 02/16/2023] [Accepted: 03/05/2023] [Indexed: 05/03/2023]
Abstract
Life on Earth has evolved to thrive in the Earth's natural gravitational field; however, as space technology advances, we must revisit and investigate the effects of unnatural conditions on human health, such as gravitational change. Studies have shown that microgravity has a negative impact on various systemic parts of humans, with the effects being more severe in the human immune system. Increasing costs, limited experimental time, and sample handling issues hampered our understanding of this field. To address the existing knowledge gap and provide confidence in modelling the phenomena, in this review, we highlight experimental works in mechano-immunology under microgravity and different computational modelling approaches that can be used to address the existing problems.
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Affiliation(s)
- Anirudh Murali
- Chemical Engineering and Process Development, CSIR - National Chemical Laboratory, Pune, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India
| | - Ram Rup Sarkar
- Chemical Engineering and Process Development, CSIR - National Chemical Laboratory, Pune, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, 201002, India.
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18
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Wang JM, Li ZF, Qi HY, Zhao Z, Yang WX. es-Arp3 and es-Eps8 regulate spermatogenesis via microfilaments in the seminiferous tubule of Eriocheir sinensis. Tissue Cell 2023; 81:102028. [PMID: 36709695 DOI: 10.1016/j.tice.2023.102028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 12/13/2022] [Accepted: 01/16/2023] [Indexed: 01/19/2023]
Abstract
Spermatogenesis is a complicated process that includes spermatogonia differentiation, spermatocytes meiosis, spermatids spermiogenesis and final release of spermatozoa. Actin-related protein 3 (Arp3) and epidermal growth factor receptor pathway substrate 8 (Eps8) are two actin binding proteins that regulate cell adhesion in seminiferous tubules during mammalian spermatogenesis. However, the functions of these two proteins during spermatogenesis in nonmammalian species, especially Crustacea, are still unknown. Here, we cloned es-Arp3 and es-Eps8 from the testis of Chinese mitten crab Eriocheir sinensis. es-Arp3 and es-Eps8 were located in spermatocytes, spermatids and spermatozoa. Knockdown of es-Arp3 and es-Eps8 in vivo caused morphological changes to seminiferous tubules including delayed spermatozoa release, shedding of germ cells and vacuoles. Filamentous-actin (F-actin) filaments network was disorganized due to deficiency of es-Arp3 and es-Eps8. Accompanying this, four junctional proteins (α-catenin, β-catenin, pinin and ZO1) displayed abnormal expression levels as well as penetrating biotin signals in seminiferous tubules. We also used the Arp2/3 complex inhibitor CK666 to block es-Arp3 activity and supported es-Arp3 knockdown results. In summary, our study demonstrated for the first time that es-Arp3 and es-Eps8 are important for spermatogenesis via regulating microfilament-mediated cell adhesion in Eriocheir sinensis.
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Affiliation(s)
- Jia-Ming Wang
- The Sperm Laboratory, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Zhen-Fang Li
- The Sperm Laboratory, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Hong-Yu Qi
- The Sperm Laboratory, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Zhan Zhao
- The Sperm Laboratory, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Wan-Xi Yang
- The Sperm Laboratory, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
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19
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Oliveira MMS, D'Aulerio R, Yong T, He M, Baptista MAP, Nylén S, Westerberg LS. Increased cross-presentation by dendritic cells and enhanced anti-tumour therapy using the Arp2/3 inhibitor CK666. Br J Cancer 2023; 128:982-991. [PMID: 36631633 PMCID: PMC10006228 DOI: 10.1038/s41416-022-02135-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Revised: 12/11/2022] [Accepted: 12/21/2022] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Dendritic cell (DC) vaccines for cancer therapy offer the possibility to let the patient's own immune system kill cancer cells. However, DC vaccines have shown less efficacy than expected due to failure to induce cancer cell killing and by activating T regulatory cells. METHODS We tested if inhibition of signalling via WASp and Arp2/3 using the small molecule CK666 would enhance DC-mediated killing of tumour cells in vitro and in vivo. RESULTS Using CK666 during the ex vivo phase of antigen processing of ovalbumin (OVA), murine and human DCs showed decreased phagosomal acidification, indicating activation of the cross-presentation pathway. When compared to untreated DCs, DCs treated with CK666 during uptake and processing of OVA-induced increased proliferation of OVA-specific CD8+ OT-I T cells in vitro and in vivo. Using the aggressive B16-mOVA melanoma tumour model, we show that mice injected with CK666-treated DCs and OVA-specific CD8+ OT-I T cells showed higher rejection of B16 melanoma cells when compared to mice receiving non-treated DCs. This resulted in the prolonged survival of tumour-bearing mice receiving CK666-treated DCs. Moreover, combining CK666-treated DCs with the checkpoint inhibitor anti-PD1 further prolonged survival. CONCLUSION Our data suggest that the small molecule inhibitor CK666 is a good candidate to enhance DC cross-presentation for cancer therapy.
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Affiliation(s)
- Mariana M S Oliveira
- Department of Microbiology Tumor and Cell biology, Karolinska Institutet, 17177, Stockholm, Sweden
| | - Roberta D'Aulerio
- Department of Microbiology Tumor and Cell biology, Karolinska Institutet, 17177, Stockholm, Sweden
| | - Tracer Yong
- Department of Microbiology Tumor and Cell biology, Karolinska Institutet, 17177, Stockholm, Sweden
| | - Minghui He
- Department of Microbiology Tumor and Cell biology, Karolinska Institutet, 17177, Stockholm, Sweden
| | - Marisa A P Baptista
- Institute for Virology and Immunobiology, Julius-Maximilians-University Würzburg, Würzburg, Germany
| | - Susanne Nylén
- Department of Microbiology Tumor and Cell biology, Karolinska Institutet, 17177, Stockholm, Sweden
| | - Lisa S Westerberg
- Department of Microbiology Tumor and Cell biology, Karolinska Institutet, 17177, Stockholm, Sweden.
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20
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Rosenbloom AD, Pollard TD. The proline-rich domain of fission yeast WASp (Wsp1p) interacts with actin filaments and inhibits actin polymerization. FEBS Lett 2023; 597:672-681. [PMID: 36650956 PMCID: PMC10023459 DOI: 10.1002/1873-3468.14571] [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: 11/21/2022] [Accepted: 12/01/2022] [Indexed: 01/19/2023]
Abstract
Members of the Wiskott-Aldrich Syndrome protein (WASp) family activate Arp2/3 complex (actin-related proteins 2 and 3 complex) to form actin filament branches. The proline-rich domain (PRD) of WASp contributes to branching nucleation, and the PRD of budding yeast Las17 binds actin filaments [Urbanek AN et al. (2013) Curr Biol 23, 196-203]. Biochemical assays showed the recombinant PRD of fission yeast Schizosaccharomyces pombe Wsp1p binds actin filaments with micromolar affinity. Recombinant PRDs of both Wsp1p and Las17p slowed the elongation of actin filaments by Mg-ATP-actin monomers by half and slowed the spontaneous polymerization of Mg-ATP-actin monomers modestly. The affinity of PRDs of WASp-family proteins for actin filaments is high enough to contribute to the reported stimulation of actin filament branching by Arp2/3 complex.
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Affiliation(s)
- Aaron D. Rosenbloom
- Department of Chemistry, Yale University, PO Box 208107, New Haven, CT 06520-8103 USA
| | - Thomas D. Pollard
- Departments of Molecular Cellular and Developmental Biology, of Molecular Biophysics and Biochemistry and of Cell Biology, Yale University, PO Box 208103, New Haven, CT 06520-8103 USA
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21
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Stromberg KA, Spain T, Tomlin SA, Amarillo KD, Schroeder CM. Evolutionary diversification reveals distinct somatic versus germline cytoskeletal functions of the Arp2 branched actin nucleator protein. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.02.25.530036. [PMID: 36909544 PMCID: PMC10002617 DOI: 10.1101/2023.02.25.530036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
Branched actin networks are critical in many cellular processes, including cell motility and division. Arp2, a protein within the 7-membered Arp2/3 complex, is responsible for generating branched actin. Given its essential roles, Arp2 evolves under stringent sequence conservation throughout eukaryotic evolution. We unexpectedly discovered recurrent evolutionary diversification of Arp2 in Drosophila, yielding independently arising paralogs Arp2D in obscura species and Arp2D2 in montium species. Both paralogs are unusually testis-enriched in expression relative to Arp2. We investigated whether their sequence divergence from canonical Arp2 led to functional specialization by replacing Arp2 in D. melanogaster with either Arp2D or Arp2D2. Despite their divergence, we surprisingly found both complement Arp2's essential function in the soma, suggesting they have preserved the ability to polymerize branched actin even in a non-native species. However, we found that Arp2D-expressing males are subfertile and display many defects throughout sperm development. We pinpointed two highly diverged structural regions in Arp2D that contribute to these defects: subdomain 2 and the C-terminus. We expected that germline function would be rescued by replacing Arp2D's long and charged C-terminus with Arp2's short C-terminus, yet surprisingly, the essential somatic function of Arp2D was lost. Therefore, while Arp2D's structural divergence is incompatible with D. melanogaster sperm development, its unique C-terminus has evolved a critical role in actin polymerization. Our findings suggest canonical Arp2's function differs between somatic versus germline contexts, and Arp2 paralogs have recurrently evolved and specialized for actin branching in the testis.
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Affiliation(s)
| | - Tristan Spain
- Department of Pharmacology, UT Southwestern Medical Center, Dallas, TX
| | - Sarah A. Tomlin
- Division of Basic Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA
- Howard Hughes Medical Institute, Fred Hutchinson Cancer Research Center, Seattle, WA
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22
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Miao T, Bao H, Ling H, Li P, Zhang Y, He Y, Hu X, Ling C, Liu Y, Tang W, Liu Y, Wang S. Comparative Transcriptomic Analysis Revealed the Suppression and Alternative Splicing of Kiwifruit ( Actinidia latifolia) NAP1 Gene Mediating Trichome Development. Int J Mol Sci 2023; 24:4481. [PMID: 36901911 PMCID: PMC10003061 DOI: 10.3390/ijms24054481] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 01/16/2023] [Accepted: 01/23/2023] [Indexed: 02/26/2023] Open
Abstract
Kiwifruit (Actinidia chinensis) is commonly covered by fruit hairs (trichomes) that affect kiwifruit popularity in the commercial market. However, it remains largely unknown which gene mediates trichome development in kiwifruit. In this study, we analyzed two kiwifruit species, A. eriantha (Ae) with long, straight, and bushy trichomes and A. latifolia (Al) with short, distorted, and spare trichomes, by second- and third-generation RNA sequencing. Transcriptomic analysis indicated that the expression of the NAP1 gene, a positive regulator of trichome development, was suppressed in Al compared with that in Ae. Additionally, the alternative splicing of AlNAP1 produced two short transcripts (AlNAP1-AS1 and AlNAP1-AS2) lacking multiple exons, in addition to a full-length transcript of AlNAP1-FL. The defects of trichome development (short and distorted trichome) in Arabidopsis nap1 mutant were rescued by AlNAP1-FL but not by AlNAP1-AS1. AlNAP1-FL gene does not affect trichome density in nap1 mutant. The qRT-PCR analysis indicated that the alternative splicing further reduces the level of functional transcripts. These results indicated that the short and distorted trichomes in Al might be caused by the suppression and alternative splicing of AlNAP1. Together, we revealed that AlNAP1 mediates trichome development and is a good candidate target for genetic modification of trichome length in kiwifruit.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | - Yajing Liu
- School of Horticulture, Anhui Agricultural University, Hefei 230036, China
| | - Songhu Wang
- School of Horticulture, Anhui Agricultural University, Hefei 230036, China
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23
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Daeden A, Mietke A, Derivery E, Seum C, Jülicher F, Gonzalez-Gaitan M. Polarized branched Actin modulates cortical mechanics to produce unequal-size daughters during asymmetric division. Nat Cell Biol 2023; 25:235-245. [PMID: 36747081 PMCID: PMC9928585 DOI: 10.1038/s41556-022-01058-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 11/22/2022] [Indexed: 02/08/2023]
Abstract
The control of cell shape during cytokinesis requires a precise regulation of mechanical properties of the cell cortex. Only few studies have addressed the mechanisms underlying the robust production of unequal-sized daughters during asymmetric cell division. Here we report that unequal daughter-cell sizes resulting from asymmetric sensory organ precursor divisions in Drosophila are controlled by the relative amount of cortical branched Actin between the two cell poles. We demonstrate this by mistargeting the machinery for branched Actin dynamics using nanobodies and optogenetics. We can thereby engineer the cell shape with temporal precision and thus the daughter-cell size at different stages of cytokinesis. Most strikingly, inverting cortical Actin asymmetry causes an inversion of daughter-cell sizes. Our findings uncover the physical mechanism by which the sensory organ precursor mother cell controls relative daughter-cell size: polarized cortical Actin modulates the cortical bending rigidity to set the cell surface curvature, stabilize the division and ultimately lead to unequal daughter-cell size.
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Affiliation(s)
- Alicia Daeden
- Department of Biochemistry, Faculty of Sciences, University of Geneva, Geneva, Switzerland
| | - Alexander Mietke
- Department of Mathematics, Massachusetts Institute of Technology, Cambridge, MA, USA
- Max Planck Institute for the Physics of Complex Systems, Dresden, Germany
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
- Center for Systems Biology Dresden, Dresden, Germany
| | - Emmanuel Derivery
- Department of Biochemistry, Faculty of Sciences, University of Geneva, Geneva, Switzerland
- MRC Laboratory of Molecular Biology, Cambridge, UK
| | - Carole Seum
- Department of Biochemistry, Faculty of Sciences, University of Geneva, Geneva, Switzerland
| | - Frank Jülicher
- Max Planck Institute for the Physics of Complex Systems, Dresden, Germany
| | - Marcos Gonzalez-Gaitan
- Department of Biochemistry, Faculty of Sciences, University of Geneva, Geneva, Switzerland.
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24
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Zhang J, Ding Z, Chen L, Qin H. Hypermethylated WASF2: tumor suppressive role in head and neck squamous cell carcinoma. Transl Cancer Res 2023; 12:78-92. [PMID: 36760387 PMCID: PMC9906064 DOI: 10.21037/tcr-22-1133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 12/03/2022] [Indexed: 01/05/2023]
Abstract
Background WASF2 regulates actin reorganization during cell migration. WASF2 has been identified as a regulator of the development of gastric cancer, breast cancer, and pancreatic cancer. But its regulatory mechanisms remain unknown. Also, its function was absent in head and neck squamous cell carcinoma (HNSCC). Consequently, we examined the effect of DNA methylation on aberrant WASF2 expression in HNSCC. Methods TNMplot, TIMER, GSEA pathway analysis, and the Kaplan-Meier Plotter database were used to analyze the expression, function, and prognostic value of WASF2, as well as the correlation between WASF2 and infiltrating immune cells in HNSCC or pan-cancer analysis. WASF2 promoter methylation levels and the correlation between WASF2 expression and WASF2 promoter methylation in HNSCC were evaluated using the DNMIVD database. The effect of DNA methylation inhibitor on WASF2 expression was demonstrated in the GEO database. Finally, the TISIDB database determined the relationships between WASF2 methylation, immune cell infiltration, and immune inhibitors. Results WASF2 was significantly downregulated in HNSCC tissues where WASF2 promoter methylation was elevated. According to the GEO database, treatment with a DNA methylation inhibitor notably restored the mRNA expression of WASF2. WASF2 expression was also a favorable indicator of human papilloma virus (HPV)-positive HNSCC. Its level of promoter methylation had detrimental effects on patient survival. In addition, patients with elevated levels of WASF2 demonstrated active G2/M regulation, TGF-β signaling, Kras signaling, fatty acid metabolism, and p53 pathways. WASF2 was positively associated with tumor-killing immune cells, while WASF2 methylation was positively related to immunosuppressive cells and immune-inhibitors. Conclusions Hypermethylated WASF2 acted as a tumor suppressor of HNSCC by regulating tumor formation and immune imbalance.
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Affiliation(s)
- Jianyun Zhang
- Central Laboratory of Stomatology, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, China
| | - Zhuang Ding
- Central Laboratory of Stomatology, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, China
| | - Long Chen
- Central Laboratory of Stomatology, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, China
| | - Haiyan Qin
- Department of Dental Implantology and Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, China
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Chou SZ, Chatterjee M, Pollard TD. Mechanism of actin filament branch formation by Arp2/3 complex revealed by a high-resolution cryo-EM structureof the branch junction. Proc Natl Acad Sci U S A 2022; 119:e2206722119. [PMID: 36442092 PMCID: PMC9894260 DOI: 10.1073/pnas.2206722119] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Accepted: 10/17/2022] [Indexed: 11/29/2022] Open
Abstract
We reconstructed the structure of actin filament branch junctions formed by fission yeast Arp2/3 complex at 3.5 Å resolution from images collected by electron cryo-microscopy. During specimen preparation, all of the actin subunits and Arp3 hydrolyzed their bound adenosine triphosphate (ATP) and dissociated the γ-phosphate, but Arp2 retained the γ-phosphate. Binding tightly to the side of the mother filament and nucleating the daughter filament growing as a branch requires Arp2/3 complex to undergo a dramatic conformational change where two blocks of structure rotate relative to each other about 25° to align Arp2 and Arp3 as the first two subunits in the branch. During branch formation, Arp2/3 complex acquires more than 8,000 Å2 of new buried surface, accounting for the stability of the branch. Inactive Arp2/3 complex binds only transiently to the side of an actin filament, because its conformation allows only a subset of the interactions found in the branch junction.
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Affiliation(s)
- Steven Z. Chou
- Department of Molecular Cellular and Developmental Biology, Yale University, New Haven, CT06520
| | - Moon Chatterjee
- Department of Molecular Cellular and Developmental Biology, Yale University, New Haven, CT06520
| | - Thomas D. Pollard
- Department of Molecular Cellular and Developmental Biology, Yale University, New Haven, CT06520
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT06520
- Department of Cell Biology, Yale University, New Haven, CT06520
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26
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Ahn HR, Baek GO, Yoon MG, Son JA, Yoon JH, Cheong JY, Cho HJ, Kang HC, Eun JW, Kim SS. Hypomethylation-mediated upregulation of the WASF2 promoter region correlates with poor clinical outcomes in hepatocellular carcinoma. J Exp Clin Cancer Res 2022; 41:158. [PMID: 35477411 PMCID: PMC9047373 DOI: 10.1186/s13046-022-02365-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 04/17/2022] [Indexed: 11/10/2022] Open
Abstract
Background Hepatocellular carcinoma (HCC) is one of the most common and lethal cancers worldwide. Wiskott–Aldrich syndrome protein family member 2 (WASF2) is an integral member of the actin cytoskeleton pathway, which plays a crucial role in cell motility. In this study, we aimed to explore the role of WASF2 in HCC carcinogenesis and its regulatory mechanism. Methods WASF2 expression in HCC was analyzed using six public RNA-seq datasets and 66 paired tissues from patients with HCC. The role of WASF2 in normal hepatocyte cell phenotypes was evaluated using a WASF2 overexpression vector in vitro; it was evaluated in HCC cell phenotypes using small interfering RNA (siRNA) in vitro and in vivo. Epigenetic regulatory mechanism of WASF2 was assessed in the Cancer Genome Atlas liver hepatocellular carcinoma project (TCGA_LIHC) dataset and also validated in 38 paired HCC tissues. Site mutagenesis, bisulfite sequencing polymerase chain reaction (BSP), methylation-specific polymerase chain reaction (MSP), and quantitative MSP (qMSP) were used for evaluating WASF2 methylation status. Results WASF2 is overexpressed in HCC and is clinically correlated with its prognosis. WASF2 overexpression promoted normal hepatocyte proliferation. WASF2 inactivation decreased the viability, growth, proliferation, migration, and invasion of Huh-7 and SNU475 HCC cells by inducing G2/M phase arrest. This induced cell death and inhibited epithelial–mesenchymal transition, hindering actin polymerization. In addition, WASF2 knockdown using siWASF2 in a xenograft mouse model and a lung metastasis model exerted tumor suppressive effect. There was a negative correlation between WASF2 methylation status and mRNA expression. The methylation pattern of CpG site 2 (− 726 bp), located in the WASF2 promoter, plays an important role in the regulation of WASF2 expression. Furthermore, the cg242579 CpG island in the WASF2 5′ promoter region was hypomethylated in HCC compared to that in the matched non-tumor samples. Patients with high WASF2 methylation and low WASF2 expression displayed the highest overall survival. Conclusions WASF2 is overexpressed and hypomethylated in HCC and correlates with patient prognosis. WASF2 inactivation exerts anti-tumorigenic effects on HCC cells in vitro and in vivo, suggesting that WASF2 could be a potential therapeutic target for HCC. Supplementary Information The online version contains supplementary material available at 10.1186/s13046-022-02365-7.
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Basu A, Paul MK, Weiss S. The actin cytoskeleton: Morphological changes in pre- and fully developed lung cancer. BIOPHYSICS REVIEWS 2022; 3:041304. [PMID: 38505516 PMCID: PMC10903407 DOI: 10.1063/5.0096188] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Accepted: 12/09/2022] [Indexed: 03/21/2024]
Abstract
Actin, a primary component of the cell cytoskeleton can have multiple isoforms, each of which can have specific properties uniquely suited for their purpose. These monomers are then bound together to form polymeric filaments utilizing adenosine triphosphate hydrolysis as a source of energy. Proteins, such as Arp2/3, VASP, formin, profilin, and cofilin, serve important roles in the polymerization process. These filaments can further be linked to form stress fibers by proteins called actin-binding proteins, such as α-actinin, myosin, fascin, filamin, zyxin, and epsin. These stress fibers are responsible for mechanotransduction, maintaining cell shape, cell motility, and intracellular cargo transport. Cancer metastasis, specifically epithelial mesenchymal transition (EMT), which is one of the key steps of the process, is accompanied by the formation of thick stress fibers through the Rho-associated protein kinase, MAPK/ERK, and Wnt pathways. Recently, with the advent of "field cancerization," pre-malignant cells have also been demonstrated to possess stress fibers and related cytoskeletal features. Analytical methods ranging from western blot and RNA-sequencing to cryo-EM and fluorescent imaging have been employed to understand the structure and dynamics of actin and related proteins including polymerization/depolymerization. More recent methods involve quantifying properties of the actin cytoskeleton from fluorescent images and utilizing them to study biological processes, such as EMT. These image analysis approaches exploit the fact that filaments have a unique structure (curvilinear) compared to the noise or other artifacts to separate them. Line segments are extracted from these filament images that have assigned lengths and orientations. Coupling such methods with statistical analysis has resulted in development of a new reporter for EMT in lung cancer cells as well as their drug responses.
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Affiliation(s)
| | | | - Shimon Weiss
- Author to whom correspondence should be addressed:
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28
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Molina-Pelayo C, Olguin P, Mlodzik M, Glavic A. The conserved Pelado/ZSWIM8 protein regulates actin dynamics by promoting linear actin filament polymerization. Life Sci Alliance 2022; 5:5/12/e202201484. [PMID: 35940847 PMCID: PMC9375228 DOI: 10.26508/lsa.202201484] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 07/15/2022] [Accepted: 07/18/2022] [Indexed: 11/24/2022] Open
Abstract
Actin filament polymerization can be branched or linear, which depends on the associated regulatory proteins. Competition for actin monomers occurs between proteins that induce branched or linear actin polymerization. Cell specialization requires the regulation of actin filaments to allow the formation of cell type-specific structures, like cuticular hairs in Drosophila, formed by linear actin filaments. Here, we report the functional analysis of CG34401/pelado, a gene encoding a SWIM domain-containing protein, conserved throughout the animal kingdom, called ZSWIM8 in mammals. Mutant pelado epithelial cells display actin hair elongation defects. This phenotype is reversed by increasing actin monomer levels or by either pushing linear actin polymerization or reducing branched actin polymerization. Similarly, in hemocytes, Pelado is essential to induce filopodia, a linear actin-based structure. We further show that this function of Pelado/ZSWIM8 is conserved in human cells, where Pelado inhibits branched actin polymerization in a cell migration context. In summary, our data indicate that the function of Pelado/ZSWIM8 in regulating actin cytoskeletal dynamics is conserved, favoring linear actin polymerization at the expense of branched filaments.
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Affiliation(s)
- Claudia Molina-Pelayo
- Department of Cell, Developmental, and Regenerative Biology, Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA.,Departamento de Biología, Centro FONDAP de Regulación del Genoma, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
| | - Patricio Olguin
- Department of Cell, Developmental, and Regenerative Biology, Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA .,Departamento de Neurociencia, Programa de Genética Humana, Instituto de Ciencias Biomédicas, Instituto de Neurociencia Biomédica, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Marek Mlodzik
- Department of Cell, Developmental, and Regenerative Biology, Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Alvaro Glavic
- Departamento de Biología, Centro FONDAP de Regulación del Genoma, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
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Lappalainen P, Kotila T, Jégou A, Romet-Lemonne G. Biochemical and mechanical regulation of actin dynamics. Nat Rev Mol Cell Biol 2022; 23:836-852. [PMID: 35918536 DOI: 10.1038/s41580-022-00508-4] [Citation(s) in RCA: 71] [Impact Index Per Article: 35.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/13/2022] [Indexed: 12/30/2022]
Abstract
Polymerization of actin filaments against membranes produces force for numerous cellular processes, such as migration, morphogenesis, endocytosis, phagocytosis and organelle dynamics. Consequently, aberrant actin cytoskeleton dynamics are linked to various diseases, including cancer, as well as immunological and neurological disorders. Understanding how actin filaments generate forces in cells, how force production is regulated by the interplay between actin-binding proteins and how the actin-regulatory machinery responds to mechanical load are at the heart of many cellular, developmental and pathological processes. During the past few years, our understanding of the mechanisms controlling actin filament assembly and disassembly has evolved substantially. It has also become evident that the activities of key actin-binding proteins are not regulated solely by biochemical signalling pathways, as mechanical regulation is critical for these proteins. Indeed, the architecture and dynamics of the actin cytoskeleton are directly tuned by mechanical load. Here we discuss the general mechanisms by which key actin regulators, often in synergy with each other, control actin filament assembly, disassembly, and monomer recycling. By using an updated view of actin dynamics as a framework, we discuss how the mechanics and geometry of actin networks control actin-binding proteins, and how this translates into force production in endocytosis and mesenchymal cell migration.
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Affiliation(s)
- Pekka Lappalainen
- Institute of Biotechnology and Helsinki Institute of Life Sciences, University of Helsinki, Helsinki, Finland.
| | - Tommi Kotila
- Institute of Biotechnology and Helsinki Institute of Life Sciences, University of Helsinki, Helsinki, Finland
| | - Antoine Jégou
- Université Paris Cité, CNRS, Institut Jacques Monod, Paris, France
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Jang HJ, Yoon YJ, Choi J, Lee YJ, Lee S, Cho W, Byun WG, Park SB, Han DC, Kwon BM. S-Benproperine, an Active Stereoisomer of Benproperine, Suppresses Cancer Migration and Tumor Metastasis by Targeting ARPC2. Pharmaceuticals (Basel) 2022; 15:ph15121462. [PMID: 36558913 PMCID: PMC9785746 DOI: 10.3390/ph15121462] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 11/19/2022] [Accepted: 11/22/2022] [Indexed: 11/29/2022] Open
Abstract
Metastasis, in which cancer cells migrate to other tissues and form new tumors, is a major cause of both cancer death and treatment failure. In a previous study, benproperine (Benp) was identified as a cancer cell migration inhibitor and an inhibitor of actin-related protein 2/3 complex subunit 2 (ARPC2). However, Benp is a racemic mixture, and which stereoisomer is the active isomer remains unclear. In this study, we found that S-Benp is an active isomer and inhibits the migration and invasion of cancer cells much more strongly than R-Benp, with no effect on normal cells. The metastasis inhibitory effect of S-Benp was also verified in an animal model. Validating that inhibitors bind to their targets in cells and tissues has been a very challenging task in drug discovery. The direct interactions between ARPC2 and S-Benp were verified by surface plasmon resonance analysis (SPR), a cellular thermal shift assay (CETSA), and drug affinity responsive target stability (DARTS). In the mutant study with ARPC2F225A cells, S-Benp did not bind to ARPC2F225A according to CETSA and DARTS. Furthermore, we validated that S-Benp colocalized with ARPC2 in cancer cells and directly bound to ARPC2 in tumor tissues using Cy3-conjugated S-Benp according to CETSA. Finally, actin polymerization assays and immunocytochemistry showed that S-Benp suppressed actin remodeling such as lamellipodium formation. Taken together, our data suggest that S-Benp is an active stereoisomer of Benp and a potential metastasis inhibitor via ARPC2 binding.
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Affiliation(s)
- Hyun-Jin Jang
- Laboratory of Chemical Biology and Genomics, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahakro, Daejeon 34141, Republic of Korea
| | - Yae Jin Yoon
- Laboratory of Chemical Biology and Genomics, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahakro, Daejeon 34141, Republic of Korea
| | - Jiyeon Choi
- Laboratory of Chemical Biology and Genomics, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahakro, Daejeon 34141, Republic of Korea
| | - Yu-Jin Lee
- Laboratory of Chemical Biology and Genomics, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahakro, Daejeon 34141, Republic of Korea
| | - Sangku Lee
- Laboratory of Chemical Biology and Genomics, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahakro, Daejeon 34141, Republic of Korea
| | - Wansang Cho
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Wan Gi Byun
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Seung Bum Park
- Department of Chemistry, Seoul National University, Seoul 08826, Republic of Korea
| | - Dong Cho Han
- Laboratory of Chemical Biology and Genomics, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahakro, Daejeon 34141, Republic of Korea
- KRIBB School of Bioscience, University of Science and Technology in Korea, 217 Gajeongro, Daejeon 34113, Republic of Korea
- Correspondence: (D.C.H.); (B.-M.K.)
| | - Byoung-Mog Kwon
- Laboratory of Chemical Biology and Genomics, Korea Research Institute of Bioscience and Biotechnology, 125 Gwahakro, Daejeon 34141, Republic of Korea
- Central Research Institute, VS Pharm Tech Co., Ltd., Daejeon 35209, Republic of Korea
- Correspondence: (D.C.H.); (B.-M.K.)
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31
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Garcia G, Bar‐Ziv R, Averbukh M, Dasgupta N, Dutta N, Zhang H, Fan W, Moaddeli D, Tsui CK, Castro Torres T, Alcala A, Moehle EA, Hoang S, Shalem O, Adams PD, Thorwald MA, Higuchi‐Sanabria R. Large-scale genetic screens identify BET-1 as a cytoskeleton regulator promoting actin function and life span. Aging Cell 2022; 22:e13742. [PMID: 36404134 PMCID: PMC9835578 DOI: 10.1111/acel.13742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 10/17/2022] [Accepted: 11/01/2022] [Indexed: 11/22/2022] Open
Abstract
The actin cytoskeleton is a three-dimensional scaffold of proteins that is a regulatory, energyconsuming network with dynamic properties to shape the structure and function of the cell. Proper actin function is required for many cellular pathways, including cell division, autophagy, chaperone function, endocytosis, and exocytosis. Deterioration of these processes manifests during aging and exposure to stress, which is in part due to the breakdown of the actin cytoskeleton. However, the regulatory mechanisms involved in preservation of cytoskeletal form and function are not well-understood. Here, we performed a multipronged, cross-organismal screen combining a whole-genome CRISPR-Cas9 screen in human fibroblasts with in vivo Caenorhabditis elegans synthetic lethality screening. We identified the bromodomain protein, BET-1, as a key regulator of actin function and longevity. Overexpression of bet-1 preserves actin function at late age and promotes life span and healthspan in C. elegans. These beneficial effects are mediated through actin preservation by the transcriptional regulator function of BET-1. Together, our discovery assigns a key role for BET-1 in cytoskeletal health, highlighting regulatory cellular networks promoting cytoskeletal homeostasis.
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Affiliation(s)
- Gilberto Garcia
- Leonard Davis School of GerontologyUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - Raz Bar‐Ziv
- Department of Molecular & Cellular Biology, Howard Hughes Medical InstituteThe University of California, BerkeleyBerkeleyCaliforniaUSA
| | - Maxim Averbukh
- Leonard Davis School of GerontologyUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - Nirmalya Dasgupta
- Aging, Cancer and Immuno‐oncology ProgramSanford Burnham Prebys Medical Discovery InstituteLa JollaCaliforniaUSA
| | - Naibedya Dutta
- Leonard Davis School of GerontologyUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - Hanlin Zhang
- Department of Molecular & Cellular Biology, Howard Hughes Medical InstituteThe University of California, BerkeleyBerkeleyCaliforniaUSA
| | - Wudi Fan
- Department of Molecular & Cellular Biology, Howard Hughes Medical InstituteThe University of California, BerkeleyBerkeleyCaliforniaUSA
| | - Darius Moaddeli
- Leonard Davis School of GerontologyUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - C. Kimberly Tsui
- Department of Molecular & Cellular Biology, Howard Hughes Medical InstituteThe University of California, BerkeleyBerkeleyCaliforniaUSA
| | - Toni Castro Torres
- Leonard Davis School of GerontologyUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - Athena Alcala
- Leonard Davis School of GerontologyUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - Erica A. Moehle
- Department of Molecular & Cellular Biology, Howard Hughes Medical InstituteThe University of California, BerkeleyBerkeleyCaliforniaUSA
| | - Sally Hoang
- Leonard Davis School of GerontologyUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - Ophir Shalem
- Department of Genetics, Perelman School of MedicineUniversity of PennsylvaniaPhiladelphiaPennsylvaniaUSA
| | - Peter D. Adams
- Aging, Cancer and Immuno‐oncology ProgramSanford Burnham Prebys Medical Discovery InstituteLa JollaCaliforniaUSA
| | - Max A. Thorwald
- Leonard Davis School of GerontologyUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
| | - Ryo Higuchi‐Sanabria
- Leonard Davis School of GerontologyUniversity of Southern CaliforniaLos AngelesCaliforniaUSA
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Huang D, Luo J, OuYang X, Song L. Subversion of host cell signaling: The arsenal of Rickettsial species. Front Cell Infect Microbiol 2022; 12:995933. [PMID: 36389139 PMCID: PMC9659576 DOI: 10.3389/fcimb.2022.995933] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2022] [Accepted: 10/04/2022] [Indexed: 10/10/2023] Open
Abstract
Rickettsia is a genus of nonmotile, Gram-negative, non-spore-forming, highly pleomorphic bacteria that cause severe epidemic rickettsioses. The spotted fever group and typhi group are major members of the genus Rickettsia. Rickettsial species from the two groups subvert diverse host cellular processes, including membrane dynamics, actin cytoskeleton dynamics, phosphoinositide metabolism, intracellular trafficking, and immune defense, to promote their host colonization and intercellular transmission through secreted effectors (virulence factors). However, lineage-specific rickettsiae have exploited divergent strategies to accomplish such challenging tasks and these elaborated strategies focus on distinct host cell processes. In the present review, we summarized current understandings of how different rickettsial species employ their effectors' arsenal to affect host cellular processes in order to promote their own replication or to avoid destruction.
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Affiliation(s)
- Dan Huang
- Department of Respiratory Medicine, Center of Pathogen Biology and Infectious Disease, Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, The First Hospital of Jilin University, Changchun, China
| | - Jingjing Luo
- Department of Respiratory Medicine, Center of Pathogen Biology and Infectious Disease, Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, The First Hospital of Jilin University, Changchun, China
| | - Xuan OuYang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Lei Song
- Department of Respiratory Medicine, Center of Pathogen Biology and Infectious Disease, Key Laboratory of Organ Regeneration and Transplantation of the Ministry of Education, The First Hospital of Jilin University, Changchun, China
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33
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Williams AM, Donoughe S, Munro E, Horne-Badovinac S. Fat2 polarizes the WAVE complex in trans to align cell protrusions for collective migration. eLife 2022; 11:e78343. [PMID: 36154691 PMCID: PMC9576270 DOI: 10.7554/elife.78343] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 09/11/2022] [Indexed: 11/13/2022] Open
Abstract
For a group of cells to migrate together, each cell must couple the polarity of its migratory machinery with that of the other cells in the cohort. Although collective cell migrations are common in animal development, little is known about how protrusions are coherently polarized among groups of migrating epithelial cells. We address this problem in the collective migration of the follicular epithelial cells in Drosophila melanogaster. In this epithelium, the cadherin Fat2 localizes to the trailing edge of each cell and promotes the formation of F-actin-rich protrusions at the leading edge of the cell behind. We show that Fat2 performs this function by acting in trans to concentrate the activity of the WASP family verprolin homolog regulatory complex (WAVE complex) at one long-lived region along each cell's leading edge. Without Fat2, the WAVE complex distribution expands around the cell perimeter and fluctuates over time, and protrusive activity is reduced and unpolarized. We further show that Fat2's influence is very local, with sub-micron-scale puncta of Fat2 enriching the WAVE complex in corresponding puncta just across the leading-trailing cell-cell interface. These findings demonstrate that a trans interaction between Fat2 and the WAVE complex creates stable regions of protrusive activity in each cell and aligns the cells' protrusions across the epithelium for directionally persistent collective migration.
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Affiliation(s)
- Audrey Miller Williams
- Department of Molecular Genetics and Cell Biology, University of ChicagoChicagoUnited States
| | - Seth Donoughe
- Department of Molecular Genetics and Cell Biology, University of ChicagoChicagoUnited States
| | - Edwin Munro
- Department of Molecular Genetics and Cell Biology, University of ChicagoChicagoUnited States
- Committee on Development, Regeneration, and Stem Cell Biology, University of ChicagoChicagoUnited States
- Institute for Biophysical Dynamics, University of ChicagoChicagoUnited States
| | - Sally Horne-Badovinac
- Department of Molecular Genetics and Cell Biology, University of ChicagoChicagoUnited States
- Committee on Development, Regeneration, and Stem Cell Biology, University of ChicagoChicagoUnited States
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Hendricks EL, Smith IR, Prates B, Barmaleki F, Liebl FLW. The CD63 homologs, Tsp42Ee and Tsp42Eg, restrict endocytosis and promote neurotransmission through differential regulation of synaptic vesicle pools. Front Cell Neurosci 2022; 16:957232. [PMID: 36072568 PMCID: PMC9441712 DOI: 10.3389/fncel.2022.957232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 08/04/2022] [Indexed: 11/30/2022] Open
Abstract
The Tetraspanin (Tsp), CD63, is a transmembrane component of late endosomes and facilitates vesicular trafficking through endosomal pathways. Despite being widely expressed in the human brain and localized to late endosomes, CD63's role in regulating endo- and exocytic cycling at the synapse has not been investigated. Synaptic vesicle pools are highly dynamic and disruptions in the mobilization and replenishment of these vesicle pools have adverse neuronal effects. We find that the CD63 homologs, Tsp42Ee and Tsp42Eg, are expressed at the Drosophila neuromuscular junction to regulate synaptic vesicle pools through both shared and unique mechanisms. Tsp42Ee and Tsp42Eg negatively regulate endocytosis and positively regulate neurotransmitter release. Both tsp mutants show impaired locomotion, reduced miniature endplate junctional current frequencies, and increased endocytosis. Expression of human CD63 in Drosophila neurons leads to impaired endocytosis suggesting the role of Tsps in endocytosis is conserved. We further show that Tsps influence the synaptic cytoskeleton and membrane composition by regulating Futsch loop formation and synaptic levels of SCAR and PI(4,5)P2. Finally, Tsp42Ee and Tsp42Eg influence the synaptic localization of several vesicle-associated proteins including Synapsin, Synaptotagmin, and Cysteine String Protein. Together, our results present a novel function for Tsps in the regulation of vesicle pools and provide insight into the molecular mechanisms of Tsp-related synaptic dysfunction.
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Affiliation(s)
| | | | | | | | - Faith L. W. Liebl
- Department of Biological Sciences, Southern Illinois University Edwardsville, Edwardsville, IL, United States
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35
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Zhao Y, Bai L, Zhang Y, Yao R, Sun Y, Hang R, Chen X, Wang H, Yao X, Xiao Y, Hang R. Type I collagen decorated nanoporous network on titanium implant surface promotes osseointegration through mediating immunomodulation, angiogenesis, and osteogenesis. Biomaterials 2022; 288:121684. [DOI: 10.1016/j.biomaterials.2022.121684] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 06/10/2022] [Accepted: 07/14/2022] [Indexed: 12/29/2022]
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36
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Fujise K, Noguchi S, Takeda T. Centronuclear Myopathy Caused by Defective Membrane Remodelling of Dynamin 2 and BIN1 Variants. Int J Mol Sci 2022; 23:ijms23116274. [PMID: 35682949 PMCID: PMC9181712 DOI: 10.3390/ijms23116274] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Revised: 05/31/2022] [Accepted: 06/01/2022] [Indexed: 02/01/2023] Open
Abstract
Centronuclear myopathy (CNM) is a congenital myopathy characterised by centralised nuclei in skeletal myofibers. T-tubules, sarcolemmal invaginations required for excitation-contraction coupling, are disorganised in the skeletal muscles of CNM patients. Previous studies showed that various endocytic proteins are involved in T-tubule biogenesis and their dysfunction is tightly associated with CNM pathogenesis. DNM2 and BIN1 are two causative genes for CNM that encode essential membrane remodelling proteins in endocytosis, dynamin 2 and BIN1, respectively. In this review, we overview the functions of dynamin 2 and BIN1 in T-tubule biogenesis and discuss how their dysfunction in membrane remodelling leads to CNM pathogenesis.
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Affiliation(s)
- Kenshiro Fujise
- Departments of Neuroscience and Cell Biology, Howard Hughes Medical Institute, Yale University School of Medicine, New Haven, CT 06520-8001, USA;
| | - Satoru Noguchi
- National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Tokyo 187-8502, Japan;
| | - Tetsuya Takeda
- Department of Biochemistry, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Shikata-cho 2-5-1, Kita-ku, Okayama 700-8558, Japan
- Correspondence: ; Tel.: +81-86-235-7125; Fax: +81-86-235-7126
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37
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Molina E, Cataldo VF, Eggers C, Muñoz-Madrid V, Glavic Á. p53 Related Protein Kinase is Required for Arp2/3-Dependent Actin Dynamics of Hemocytes in Drosophila melanogaster. Front Cell Dev Biol 2022; 10:859105. [PMID: 35721516 PMCID: PMC9201722 DOI: 10.3389/fcell.2022.859105] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Accepted: 04/22/2022] [Indexed: 11/21/2022] Open
Abstract
Cells extend membrane protrusions like lamellipodia and filopodia from the leading edge to sense, to move and to form new contacts. The Arp2/3 complex sustains lamellipodia formation, and in conjunction with the actomyosin contractile system, provides mechanical strength to the cell. Drosophila p53-related protein kinase (Prpk), a Tsc5p ortholog, has been described as essential for cell growth and proliferation. In addition, Prpk interacts with proteins associated to actin filament dynamics such as α-spectrin and the Arp2/3 complex subunit Arpc4. Here, we investigated the role of Prpk in cell shape changes, specifically regarding actin filament dynamics and membrane protrusion formation. We found that reductions in Prpk alter cell shape and the structure of lamellipodia, mimicking the phenotypes evoked by Arp2/3 complex deficiencies. Prpk co-localize and co-immunoprecipitates with the Arp2/3 complex subunit Arpc1 and with the small GTPase Rab35. Importantly, expression of Rab35, known by its ability to recruit upstream regulators of the Arp2/3 complex, could rescue the Prpk knockdown phenotypes. Finally, we evaluated the requirement of Prpk in different developmental contexts, where it was shown to be essential for correct Arp2/3 complex distribution and actin dynamics required for hemocytes migration, recruitment, and phagocytosis during immune response.
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Affiliation(s)
- Emiliano Molina
- FONDAP Center for Genome Regulation, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
| | - Vicente F. Cataldo
- Department of Chemical and Bioprocess Engineering, School of Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Cristián Eggers
- Department for Chemistry and Biochemistry and Pharmaceutical Sciences, Faculty of Science, University of Bern, Bern, Switzerland
| | - Valentina Muñoz-Madrid
- FONDAP Center for Genome Regulation, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
| | - Álvaro Glavic
- FONDAP Center for Genome Regulation, Departamento de Biología, Facultad de Ciencias, Universidad de Chile, Santiago, Chile
- *Correspondence: Álvaro Glavic,
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Vakhrusheva A, Murashko A, Trifonova E, Efremov Y, Timashev P, Sokolova O. Role of Actin-binding Proteins in the Regulation of Cellular Mechanics. Eur J Cell Biol 2022; 101:151241. [DOI: 10.1016/j.ejcb.2022.151241] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 04/18/2022] [Accepted: 05/19/2022] [Indexed: 12/25/2022] Open
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Fang X, Svitkina TM. Adenomatous polyposis coli (APC) in cell migration. Eur J Cell Biol 2022; 101:151228. [DOI: 10.1016/j.ejcb.2022.151228] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 04/15/2022] [Accepted: 04/20/2022] [Indexed: 12/22/2022] Open
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40
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Narvaez-Ortiz HY, Nolen BJ. Unconcerted conformational changes in Arp2/3 complex integrate multiple activating signals to assemble functional actin networks. Curr Biol 2022; 32:975-987.e6. [PMID: 35090589 PMCID: PMC8930562 DOI: 10.1016/j.cub.2022.01.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 11/25/2021] [Accepted: 01/04/2022] [Indexed: 11/16/2022]
Abstract
Arp2/3 complex nucleates branched actin filaments important for processes such as DNA repair, endocytosis, and cellular motility. Multiple factors are required to activate branching nucleation by Arp2/3 complex, including a WASP family protein and a pre-existing actin filament. Activation is achieved through two major conformational changes-subunit flattening and movement into the short pitch conformation-that allow the actin-related proteins (Arps) within the complex (Arp2 and Arp3) to mimic filamentous actin subunits, thereby templating new filament assembly. Some models suggest that these changes are concerted and stimulated cooperatively by WASP and actin filaments, but how Arp2/3 complex integrates signals from multiple factors to drive switch-like activation of branching nucleation has been unknown. Here, we use biochemical assays to show that instead of a concerted mechanism, signal integration by Arp2/3 complex occurs via distinct and unconcerted conformational changes; WASP stimulates the short pitch arrangement of Arp2 and Arp3, while actin filaments trigger a different activation step. An engineered Arp2/3 complex that bypasses the need for WASP but not actin filaments in activation potently assembles isotropic actin networks but fails to assemble sustained force-producing actin networks in bead motility assays. The engineered complex, which is crosslinked into the short pitch conformation, fails to target nucleation to the surface of the bead, creating unproductive branching events that deplete unpolymerized actin and halt assembly. Together, our data demonstrate the requirement for multifactor signal integration by Arp2/3 complex and highlight the importance of both the WASP- and actin filament-mediated activation steps in the assembly of functional actin networks.
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Affiliation(s)
- Heidy Y Narvaez-Ortiz
- Department of Chemistry and Biochemistry, Institute of Molecular Biology, University of Oregon, Eugene, OR 97403, USA
| | - Brad J Nolen
- Department of Chemistry and Biochemistry, Institute of Molecular Biology, University of Oregon, Eugene, OR 97403, USA.
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41
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Cytoskeleton regulation: Distinct steps in Arp2/3 complex activation. Curr Biol 2022; 32:R220-R222. [DOI: 10.1016/j.cub.2022.01.071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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42
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Fregoso FE, van Eeuwen T, Simanov G, Rebowski G, Boczkowska M, Zimmet A, Gautreau AM, Dominguez R. Molecular mechanism of Arp2/3 complex inhibition by Arpin. Nat Commun 2022; 13:628. [PMID: 35110533 PMCID: PMC8810855 DOI: 10.1038/s41467-022-28112-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 01/09/2022] [Indexed: 11/09/2022] Open
Abstract
Positive feedback loops involving signaling and actin assembly factors mediate the formation and remodeling of branched actin networks in processes ranging from cell and organelle motility to mechanosensation. The Arp2/3 complex inhibitor Arpin controls the directional persistence of cell migration by interrupting a feedback loop involving Rac-WAVE-Arp2/3 complex, but Arpin’s mechanism of inhibition is unknown. Here, we describe the cryo-EM structure of Arpin bound to Arp2/3 complex at 3.24-Å resolution. Unexpectedly, Arpin binds Arp2/3 complex similarly to WASP-family nucleation-promoting factors (NPFs) that activate the complex. However, whereas NPFs bind to two sites on Arp2/3 complex, on Arp2-ArpC1 and Arp3, Arpin only binds to the site on Arp3. Like NPFs, Arpin has a C-helix that binds at the barbed end of Arp3. Mutagenesis studies in vitro and in cells reveal how sequence differences within the C-helix define the molecular basis for inhibition by Arpin vs. activation by NPFs. The Arp2/3 complex inhibitor Arpin controls cell migration by interrupting a feedback loop involving Rac-WAVE-Arp2/3 complex Here, the authors use structural, biochemical, and cellular studies to reveal Arpin’s mechanism of inhibition.
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Affiliation(s)
- Fred E Fregoso
- Department of Physiology and Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Trevor van Eeuwen
- Department of Physiology and Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.,Laboratory of Cellular and Structural Biology, The Rockefeller University, New York, NY, 10065, USA
| | - Gleb Simanov
- Laboratoire de Biologie Structurale de la Cellule, CNRS, Institut Polytechnique de Paris, 91128, Palaiseau, France
| | - Grzegorz Rebowski
- Department of Physiology and Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Malgorzata Boczkowska
- Department of Physiology and Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Austin Zimmet
- Department of Physiology and Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Alexis M Gautreau
- Laboratoire de Biologie Structurale de la Cellule, CNRS, Institut Polytechnique de Paris, 91128, Palaiseau, France.,Skolkovo Institute of Science and Technology, 121205, Moscow, Russia
| | - Roberto Dominguez
- Department of Physiology and Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
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Xie Y, Zhou F, Ma Q, Lu L, Miao Y. A teamwork promotion of formin-mediated actin nucleation by Bud6 and Aip5 in Saccharomyces cerevisiae. Mol Biol Cell 2021; 33:ar19. [PMID: 34818061 PMCID: PMC9236144 DOI: 10.1091/mbc.e21-06-0285] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Actin nucleation is achieved by collaborative teamwork of actin nucleator factors (NFs) and nucleation-promoting factors (NPFs) into functional protein complexes. Selective inter- and intramolecular interactions between the nucleation complex constituents enable diverse modes of complex assembly in initiating actin polymerization on demand. Budding yeast has two formins, Bni1 and Bnr1, which are teamed up with different NPFs. However, the selective pairing between formin NFs and NPFs into the nucleation core for actin polymerization is not completely understood. By examining the functions and interactions of NPFs and NFs via biochemistry, genetics, and mathematical modeling approaches, we found that two NPFs, Aip5 and Bud6, showed joint teamwork effort with Bni1 and Bnr1, respectively, by interacting with the C-terminal intrinsically disordered region (IDR) of formin, in which two NPFs work together to promote formin-mediated actin nucleation. Although the C-terminal IDRs of Bni1 and Bnr1 are distinct in length, each formin IDR orchestrates the recruitment of Bud6 and Aip5 cooperatively by different positioning strategies to form a functional complex. Our study demonstrated the dynamic assembly of the actin nucleation complex by recruiting multiple partners in budding yeast, which may be a general feature for effective actin nucleation by formins.
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Affiliation(s)
- Ying Xie
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Feng Zhou
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Qianqian Ma
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Lanyuan Lu
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Yansong Miao
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
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44
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Gautreau AM, Fregoso FE, Simanov G, Dominguez R. Nucleation, stabilization, and disassembly of branched actin networks. Trends Cell Biol 2021; 32:421-432. [PMID: 34836783 PMCID: PMC9018471 DOI: 10.1016/j.tcb.2021.10.006] [Citation(s) in RCA: 57] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 10/19/2021] [Accepted: 10/22/2021] [Indexed: 12/18/2022]
Abstract
Arp2/3 complex is an actin filament nucleation and branching machinery conserved in all eukaryotes from yeast to human. Arp2/3 complex branched networks generate pushing forces that drive cellular processes ranging from membrane remodeling to cell and organelle motility. Several molecules regulate these processes by directly inhibiting or activating Arp2/3 complex and by stabilizing or disassembling branched networks. Here, we review recent advances in our understanding of Arp2/3 complex regulation, including high-resolution cryoelectron microscopy (cryo-EM) structures that illuminate the mechanisms of Arp2/3 complex activation and branch formation, and novel cellular pathways of branch formation, stabilization, and debranching. We also identify major gaps in our understanding of Arp2/3 complex inhibition and branch stabilization and disassembly.
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Affiliation(s)
- Alexis M Gautreau
- Laboratoire de Biologie Structurale de la Cellule, CNRS, École Polytechnique, Institut Polytechnique de Paris, 91128 Palaiseau, France.
| | - Fred E Fregoso
- Department of Physiology and Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Gleb Simanov
- Laboratoire de Biologie Structurale de la Cellule, CNRS, École Polytechnique, Institut Polytechnique de Paris, 91128 Palaiseau, France
| | - Roberto Dominguez
- Department of Physiology and Biochemistry and Molecular Biophysics Graduate Group, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
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45
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Crosas-Molist E, Samain R, Kohlhammer L, Orgaz J, George S, Maiques O, Barcelo J, Sanz-Moreno V. RhoGTPase Signalling in Cancer Progression and Dissemination. Physiol Rev 2021; 102:455-510. [PMID: 34541899 DOI: 10.1152/physrev.00045.2020] [Citation(s) in RCA: 86] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Rho GTPases are a family of small G proteins that regulate a wide array of cellular processes related to their key roles controlling the cytoskeleton. On the other hand, cancer is a multi-step disease caused by the accumulation of genetic mutations and epigenetic alterations, from the initial stages of cancer development when cells in normal tissues undergo transformation, to the acquisition of invasive and metastatic traits, responsible for a large number of cancer related deaths. In this review, we discuss the role of Rho GTPase signalling in cancer in every step of disease progression. Rho GTPases contribute to tumour initiation and progression, by regulating proliferation and apoptosis, but also metabolism, senescence and cell stemness. Rho GTPases play a major role in cell migration, and in the metastatic process. They are also involved in interactions with the tumour microenvironment and regulate inflammation, contributing to cancer progression. After years of intensive research, we highlight the importance of relevant models in the Rho GTPase field, and we reflect on the therapeutic opportunities arising for cancer patients.
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Affiliation(s)
- Eva Crosas-Molist
- Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Remi Samain
- Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Leonie Kohlhammer
- Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Jose Orgaz
- Barts Cancer Institute, Queen Mary University of London, London, United Kingdom.,Instituto de Investigaciones Biomédicas 'Alberto Sols', CSIC-UAM, 28029, Madrid, Spain
| | - Samantha George
- Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Oscar Maiques
- Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
| | - Jaume Barcelo
- Barts Cancer Institute, Queen Mary University of London, London, United Kingdom
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46
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The Role of WAVE2 Signaling in Cancer. Biomedicines 2021; 9:biomedicines9091217. [PMID: 34572403 PMCID: PMC8464821 DOI: 10.3390/biomedicines9091217] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2021] [Revised: 09/09/2021] [Accepted: 09/10/2021] [Indexed: 11/18/2022] Open
Abstract
The Wiskott–Aldrich syndrome protein (WASP) and WASP family verprolin-homologous protein (WAVE)—WAVE1, WAVE2 and WAVE3 regulate rapid reorganization of cortical actin filaments and have been shown to form a key link between small GTPases and the actin cytoskeleton. Upon receiving upstream signals from Rho-family GTPases, the WASP and WAVE family proteins play a significant role in polymerization of actin cytoskeleton through activation of actin-related protein 2/3 complex (Arp2/3). The Arp2/3 complex, once activated, forms actin-based membrane protrusions essential for cell migration and cancer cell invasion. Thus, by activation of Arp2/3 complex, the WAVE and WASP family proteins, as part of the WAVE regulatory complex (WRC), have been shown to play a critical role in cancer cell invasion and metastasis, drawing significant research interest over recent years. Several studies have highlighted the potential for targeting the genes encoding either part of or a complete protein from the WASP/WAVE family as therapeutic strategies for preventing the invasion and metastasis of cancer cells. WAVE2 is well documented to be associated with the pathogenesis of several human cancers, including lung, liver, pancreatic, prostate, colorectal and breast cancer, as well as other hematologic malignancies. This review focuses mainly on the role of WAVE2 in the development, invasion and metastasis of different types of cancer. This review also summarizes the molecular mechanisms that regulate the activity of WAVE2, as well as those oncogenic pathways that are regulated by WAVE2 to promote the cancer phenotype. Finally, we discuss potential therapeutic strategies that target WAVE2 or the WAVE regulatory complex, aimed at preventing or inhibiting cancer invasion and metastasis.
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47
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Kadzik RS, Homa KE, Kovar DR. F-Actin Cytoskeleton Network Self-Organization Through Competition and Cooperation. Annu Rev Cell Dev Biol 2021; 36:35-60. [PMID: 33021819 DOI: 10.1146/annurev-cellbio-032320-094706] [Citation(s) in RCA: 52] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Many fundamental cellular processes such as division, polarization, endocytosis, and motility require the assembly, maintenance, and disassembly of filamentous actin (F-actin) networks at specific locations and times within the cell. The particular function of each network is governed by F-actin organization, size, and density as well as by its dynamics. The distinct characteristics of different F-actin networks are determined through the coordinated actions of specific sets of actin-binding proteins (ABPs). Furthermore, a cell typically assembles and uses multiple F-actin networks simultaneously within a common cytoplasm, so these networks must self-organize from a common pool of shared globular actin (G-actin) monomers and overlapping sets of ABPs. Recent advances in multicolor imaging and analysis of ABPs and their associated F-actin networks in cells, as well as the development of sophisticated in vitro reconstitutions of networks with ensembles of ABPs, have allowed the field to start uncovering the underlying principles by which cells self-organize diverse F-actin networks to execute basic cellular functions.
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Affiliation(s)
- Rachel S Kadzik
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois 60637, USA; , .,Department of Molecular BioSciences, Northwestern University, Evanston, Illinois 60208, USA;
| | - Kaitlin E Homa
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois 60637, USA; ,
| | - David R Kovar
- Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois 60637, USA; , .,Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, Illinois 60637, USA
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48
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Pipathsouk A, Brunetti RM, Town JP, Graziano BR, Breuer A, Pellett PA, Marchuk K, Tran NHT, Krummel MF, Stamou D, Weiner OD. The WAVE complex associates with sites of saddle membrane curvature. J Cell Biol 2021; 220:e202003086. [PMID: 34096975 PMCID: PMC8185649 DOI: 10.1083/jcb.202003086] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 04/13/2021] [Accepted: 05/18/2021] [Indexed: 12/30/2022] Open
Abstract
How local interactions of actin regulators yield large-scale organization of cell shape and movement is not well understood. Here we investigate how the WAVE complex organizes sheet-like lamellipodia. Using super-resolution microscopy, we find that the WAVE complex forms actin-independent 230-nm-wide rings that localize to regions of saddle membrane curvature. This pattern of enrichment could explain several emergent cell behaviors, such as expanding and self-straightening lamellipodia and the ability of endothelial cells to recognize and seal transcellular holes. The WAVE complex recruits IRSp53 to sites of saddle curvature but does not depend on IRSp53 for its own localization. Although the WAVE complex stimulates actin nucleation via the Arp2/3 complex, sheet-like protrusions are still observed in ARP2-null, but not WAVE complex-null, cells. Therefore, the WAVE complex has additional roles in cell morphogenesis beyond Arp2/3 complex activation. Our work defines organizing principles of the WAVE complex lamellipodial template and suggests how feedback between cell shape and actin regulators instructs cell morphogenesis.
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Affiliation(s)
- Anne Pipathsouk
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA
| | - Rachel M. Brunetti
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA
| | - Jason P. Town
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA
| | - Brian R. Graziano
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA
| | - Artù Breuer
- Nano-Science Center and Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
| | | | - Kyle Marchuk
- Department of Pathology and Biological Imaging Development CoLab, University of California, San Francisco, San Francisco, CA
| | - Ngoc-Han T. Tran
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA
| | - Matthew F. Krummel
- Department of Pathology and Biological Imaging Development CoLab, University of California, San Francisco, San Francisco, CA
| | - Dimitrios Stamou
- Nano-Science Center and Department of Chemistry, University of Copenhagen, Copenhagen, Denmark
| | - Orion D. Weiner
- Cardiovascular Research Institute, University of California, San Francisco, San Francisco, CA
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, CA
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49
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Keller-Pinter A, Gyulai-Nagy S, Becsky D, Dux L, Rovo L. Syndecan-4 in Tumor Cell Motility. Cancers (Basel) 2021; 13:cancers13133322. [PMID: 34282767 PMCID: PMC8268284 DOI: 10.3390/cancers13133322] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 06/25/2021] [Accepted: 06/27/2021] [Indexed: 12/13/2022] Open
Abstract
Simple Summary Cell migration is crucial fReaor metastasis formation and a hallmark of malignancy. The primary cause of high mortality among oncology patients is the ability of cancer cells to metastasize. To form metastasis, primary tumor cells must be intrinsically able to move. The transmembrane, heparan sulfate proteoglycan syndecan-4 (SDC4) exhibits multiple functions in signal transduction by regulating Rac1 GTPase activity and consequently actin remodeling, as well as regulating focal adhesion kinase, protein kinase C-alpha and the level of intracellular calcium. By affecting several signaling pathways and biological processes, SDC4 is involved in cell migration under physiological and pathological conditions as well. In this review, we discuss the SDC4-mediated cell migration focusing on the role of SDC4 in tumor cell movement. Abstract Syndecan-4 (SDC4) is a ubiquitously expressed, transmembrane proteoglycan bearing heparan sulfate chains. SDC4 is involved in numerous inside-out and outside-in signaling processes, such as binding and sequestration of growth factors and extracellular matrix components, regulation of the activity of the small GTPase Rac1, protein kinase C-alpha, the level of intracellular calcium, or the phosphorylation of focal adhesion kinase. The ability of this proteoglycan to link the extracellular matrix and actin cytoskeleton enables SDC4 to contribute to biological functions like cell adhesion and migration, cell proliferation, cytokinesis, cellular polarity, or mechanotransduction. The multiple roles of SDC4 in tumor pathogenesis and progression has already been demonstrated; therefore, the expression and signaling of SDC4 was investigated in several tumor types. SDC4 influences tumor progression by regulating cell proliferation as well as cell migration by affecting cell-matrix adhesion and several signaling pathways. Here, we summarize the general role of SDC4 in cell migration and tumor cell motility.
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Affiliation(s)
- Aniko Keller-Pinter
- Department of Biochemistry, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary; (S.G.-N.); (D.B.); (L.D.)
- Correspondence:
| | - Szuzina Gyulai-Nagy
- Department of Biochemistry, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary; (S.G.-N.); (D.B.); (L.D.)
| | - Daniel Becsky
- Department of Biochemistry, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary; (S.G.-N.); (D.B.); (L.D.)
| | - Laszlo Dux
- Department of Biochemistry, Faculty of Medicine, University of Szeged, H-6720 Szeged, Hungary; (S.G.-N.); (D.B.); (L.D.)
| | - Laszlo Rovo
- Department of Oto-Rhino-Laryngology and Head-Neck Surgery, University of Szeged, H-6725 Szeged, Hungary;
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50
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Filić V, Mijanović L, Putar D, Talajić A, Ćetković H, Weber I. Regulation of the Actin Cytoskeleton via Rho GTPase Signalling in Dictyostelium and Mammalian Cells: A Parallel Slalom. Cells 2021; 10:1592. [PMID: 34202767 PMCID: PMC8305917 DOI: 10.3390/cells10071592] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 06/16/2021] [Accepted: 06/16/2021] [Indexed: 01/15/2023] Open
Abstract
Both Dictyostelium amoebae and mammalian cells are endowed with an elaborate actin cytoskeleton that enables them to perform a multitude of tasks essential for survival. Although these organisms diverged more than a billion years ago, their cells share the capability of chemotactic migration, large-scale endocytosis, binary division effected by actomyosin contraction, and various types of adhesions to other cells and to the extracellular environment. The composition and dynamics of the transient actin-based structures that are engaged in these processes are also astonishingly similar in these evolutionary distant organisms. The question arises whether this remarkable resemblance in the cellular motility hardware is accompanied by a similar correspondence in matching software, the signalling networks that govern the assembly of the actin cytoskeleton. Small GTPases from the Rho family play pivotal roles in the control of the actin cytoskeleton dynamics. Indicatively, Dictyostelium matches mammals in the number of these proteins. We give an overview of the Rho signalling pathways that regulate the actin dynamics in Dictyostelium and compare them with similar signalling networks in mammals. We also provide a phylogeny of Rho GTPases in Amoebozoa, which shows a variability of the Rho inventories across different clades found also in Metazoa.
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Affiliation(s)
- Vedrana Filić
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička 54, HR-10000 Zagreb, Croatia; (L.M.); (D.P.); (A.T.); (H.Ć.)
| | | | | | | | | | - Igor Weber
- Division of Molecular Biology, Ruđer Bošković Institute, Bijenička 54, HR-10000 Zagreb, Croatia; (L.M.); (D.P.); (A.T.); (H.Ć.)
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