1
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Niedzialkowska E, Runyan LA, Kudryashova E, Egelman EH, Kudryashov DS. Stabilization of F-actin by Salmonella effector SipA resembles the structural effects of inorganic phosphate and phalloidin. Structure 2024; 32:725-738.e8. [PMID: 38518780 PMCID: PMC11162321 DOI: 10.1016/j.str.2024.02.022] [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: 01/02/2024] [Revised: 02/08/2024] [Accepted: 02/26/2024] [Indexed: 03/24/2024]
Abstract
Entry of Salmonella into host enterocytes relies on its pathogenicity island 1 effector SipA. We found that SipA binds to F-actin in a 1:2 stoichiometry with sub-nanomolar affinity. A cryo-EM reconstruction revealed that SipA's globular core binds at the groove between actin strands, whereas the extended C-terminal arm penetrates deeply into the inter-strand space, stabilizing F-actin from within. The unusually strong binding of SipA is achieved by a combination of fast association via the core and very slow dissociation dictated by the arm. Similar to Pi, BeF3, and phalloidin, SipA potently inhibited actin depolymerization by actin depolymerizing factor (ADF)/cofilin, which correlated with increased filament stiffness, supporting the hypothesis that F-actin's mechanical properties contribute to the recognition of its nucleotide state by protein partners. The remarkably strong binding to F-actin maximizes the toxin's effects at the injection site while minimizing global influence on the cytoskeleton and preventing pathogen detection by the host cell.
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Affiliation(s)
- Ewa Niedzialkowska
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA 22903, USA
| | - Lucas A Runyan
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
| | - Elena Kudryashova
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
| | - Edward H Egelman
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA 22903, USA.
| | - Dmitri S Kudryashov
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA.
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2
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Mooren OL, McConnell P, DeBrecht JD, Jaysingh A, Cooper JA. Reconstitution of Arp2/3-Nucleated Actin Assembly with CP, V-1 and CARMIL. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.13.593916. [PMID: 38798690 PMCID: PMC11118340 DOI: 10.1101/2024.05.13.593916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Actin polymerization is often associated with membrane proteins containing capping-protein-interacting (CPI) motifs, such as CARMIL, CD2AP, and WASHCAP/Fam21. CPI motifs bind directly to actin capping protein (CP), and this interaction weakens the binding of CP to barbed ends of actin filaments, lessening the ability of CP to functionally cap those ends. The protein V-1 / myotrophin binds to the F-actin binding site on CP and sterically blocks CP from binding barbed ends. CPI-motif proteins also weaken the binding between V-1 and CP, which decreases the inhibitory effects of V-1, thereby freeing CP to cap barbed ends. Here, we address the question of whether CPI-motif proteins on a surface analogous to a membrane lead to net activation or inhibition of actin assembly nucleated by Arp2/3 complex. Using reconstitution with purified components, we discovered that CARMIL at the surface promotes and enhances actin assembly, countering the inhibitory effects of V-1 and thus activating CP. The reconstitution involves the presence of an Arp2/3 activator on the surface, along with Arp2/3 complex, V-1, CP, profilin and actin monomers in solution, recreating key features of cell physiology.
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Affiliation(s)
- Olivia L Mooren
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO
| | - Patrick McConnell
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO
| | - James D DeBrecht
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO
| | - Anshuman Jaysingh
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO
| | - John A Cooper
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO
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3
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Lamb AK, Fernandez AN, Eadaim A, Johnson K, Di Pietro SM. Mechanism of actin capping protein recruitment and turnover during clathrin-mediated endocytosis. J Cell Biol 2024; 223:e202306154. [PMID: 37966720 PMCID: PMC10651396 DOI: 10.1083/jcb.202306154] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 10/11/2023] [Accepted: 11/01/2023] [Indexed: 11/16/2023] Open
Abstract
Clathrin-mediated endocytosis depends on polymerization of a branched actin network to provide force for membrane invagination. A key regulator in branched actin network formation is actin capping protein (CP), which binds to the barbed end of actin filaments to prevent the addition or loss of actin subunits. CP was thought to stochastically bind actin filaments, but recent evidence shows CP is regulated by a group of proteins containing CP-interacting (CPI) motifs. Importantly, how CPI motif proteins function together to regulate CP is poorly understood. Here, we show Aim21 and Bsp1 work synergistically to recruit CP to the endocytic actin network in budding yeast through their CPI motifs, which also allosterically modulate capping strength. In contrast, twinfilin works downstream of CP recruitment, regulating the turnover of CP through its CPI motif and a non-allosteric mechanism. Collectively, our findings reveal how three CPI motif proteins work together to regulate CP in a stepwise fashion during endocytosis.
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Affiliation(s)
- Andrew K. Lamb
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
| | - Andres N. Fernandez
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
| | - Abdunaser Eadaim
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
| | - Katelyn Johnson
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
| | - Santiago M. Di Pietro
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO, USA
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4
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Niedzialkowska E, Runyan LA, Kudryashova E, Egelman EH, Kudryashov DS. Stabilization of F-actin by Salmonella effector SipA resembles the structural effects of inorganic phosphate and phalloidin. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.12.26.573373. [PMID: 38234808 PMCID: PMC10793455 DOI: 10.1101/2023.12.26.573373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Entry of Salmonella into host enterocytes strictly relies on its pathogenicity island 1 effector SipA. We found that SipA binds to F-actin in a unique mode in a 1:2 stoichiometry with picomolar affinity. A cryo-EM reconstruction revealed that SipA's globular core binds at the grove between actin strands, whereas the extended C-terminal arm penetrates deeply into the inter-strand space, stabilizing F-actin from within. The unusually strong binding of SipA is achieved via a combination of fast association via the core and very slow dissociation dictated by the arm. Similarly to Pi, BeF3, and phalloidin, SipA potently inhibited actin depolymerization by ADF/cofilin, which correlated with the increased filament stiffness, supporting the hypothesis that F-actin's mechanical properties contribute to the recognition of its nucleotide state by protein partners. The remarkably strong binding to F-actin maximizes the toxin's effects at the injection site while minimizing global influence on the cytoskeleton and preventing pathogen detection by the host cell.
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Affiliation(s)
- Ewa Niedzialkowska
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA 22903, USA
| | - Lucas A. Runyan
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
| | - Elena Kudryashova
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
| | - Edward H. Egelman
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA 22903, USA
| | - Dmitri S. Kudryashov
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
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5
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Mooren OL, Stuchell-Brereton MD, McConnell P, Yan C, Wilkerson EM, Goldfarb D, Cooper JA, Sept D, Soranno A. Biophysical Mechanism of Allosteric Regulation of Actin Capping Protein. J Mol Biol 2023; 435:168342. [PMID: 37924863 PMCID: PMC10872493 DOI: 10.1016/j.jmb.2023.168342] [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: 08/13/2023] [Revised: 10/28/2023] [Accepted: 10/30/2023] [Indexed: 11/06/2023]
Abstract
Actin capping protein (CP) can be regulated by steric and allosteric mechanisms. The molecular mechanism of the allosteric regulation at a biophysical level includes linkage between the binding sites for three ligands: F-actin, Capping-Protein-Interacting (CPI) motifs, and V-1/myotrophin, based on biochemical functional studies and solvent accessibility experiments. Here, we investigated the mechanism of allosteric regulation at the atomic level using single-molecule Förster resonance energy transfer (FRET) and molecular dynamics (MD) to assess the conformational and structural dynamics of CP in response to linked-binding site ligands. In the absence of ligand, both single-molecule FRET and MD revealed two distinct conformations of CP in solution; previous crystallographic studies revealed only one. Interaction with CPI-motif peptides induced conformations within CP that bring the cap and stalk closer, while interaction with V-1 moves them away from one another. Comparing CPI-motif peptides from different proteins, we identified variations in CP conformations and dynamics that are specific to each CPI motif. MD simulations for CP alone and in complex with a CPI motif and V-1 reveal atomistic details of the conformational changes. Analysis of the interaction of CP with wild-type (wt) and chimeric CPI-motif peptides using single-molecule FRET, isothermal calorimetry (ITC) and MD simulation indicated that conformational and affinity differences are intrinsic to the C-terminal portion of the CPI motif. We conclude that allosteric regulation of CP involves changes in conformation that disseminate across the protein to link distinct binding-site functions. Our results provide novel insights into the biophysical mechanism of the allosteric regulation of CP.
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Affiliation(s)
- Olivia L Mooren
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, United States
| | - Melissa D Stuchell-Brereton
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, United States; Center for Biomolecular Condensates, Washington University in St Louis, St. Louis, MO, United States
| | - Patrick McConnell
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, United States
| | - Chenbo Yan
- Department of Biophysics, University of Michigan, Ann Arbor, MI, United States
| | - Emily M Wilkerson
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, United States; Institute for Informatics, Washington University School of Medicine, St. Louis, MO, United States
| | - Dennis Goldfarb
- Department of Cell Biology and Physiology, Washington University School of Medicine, St. Louis, MO, United States; Institute for Informatics, Washington University School of Medicine, St. Louis, MO, United States
| | - John A Cooper
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, United States.
| | - David Sept
- Department of Biophysics, University of Michigan, Ann Arbor, MI, United States; Department of Biomedical Engineering, University of Michigan, Ann Arbor, MI, United States.
| | - Andrea Soranno
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, MO, United States; Center for Biomolecular Condensates, Washington University in St Louis, St. Louis, MO, United States.
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6
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Mooren OL, Stuchell-Brereton MD, McConnell P, Yan C, Wilkerson EM, Goldfarb D, Cooper JA, Sept D, Soranno A. Biophysical Mechanism of Allosteric Regulation of Actin Capping Protein. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.16.553570. [PMID: 37645735 PMCID: PMC10462145 DOI: 10.1101/2023.08.16.553570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
Actin capping protein (CP) can be regulated by steric and allosteric mechanisms. The molecular mechanism of the allosteric regulation at a biophysical level includes linkage between the binding sites for three ligands: F-actin, Capping-Protein-Interacting (CPI) motifs, and V-1/myotrophin, based on biochemical functional studies and solvent accessibility experiments. Here, we investigated the mechanism of allosteric regulation at the atomic level using single-molecule Förster resonance energy transfer (FRET) and molecular dynamics (MD) to assess the conformational and structural dynamics of CP in response to linked-binding site ligands. In the absence of ligand, both single-molecule FRET and MD revealed two distinct conformations of CP in solution; previous crystallographic studies revealed only one. CPI-motif peptide association induced conformational changes within CP that propagate in one direction, while V-1 association induced conformational changes in the opposite direction. Comparing CPI-motif peptides from different proteins, we identified variations in CP conformations and dynamics that are specific to each CPI motif. MD simulations for CP alone and in complex with a CPI motif and V-1 reveal atomistic details of the conformational changes. Analysis of the interaction of CP with wildtype (wt) and chimeric CPI-motif peptides using single-molecule FRET, isothermal calorimetry (ITC) and MD simulation indicated that conformational and affinity differences are intrinsic to the C-terminal portion of the CPI-motif. We conclude that allosteric regulation of CP involves changes in conformation that disseminate across the protein to link distinct binding-site functions. Our results provide novel insights into the biophysical mechanism of the allosteric regulation of CP.
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7
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Kudryashova E, Ankita, Ulrichs H, Shekhar S, Kudryashov DS. Pointed-end processive elongation of actin filaments by Vibrio effectors VopF and VopL. SCIENCE ADVANCES 2022; 8:eadc9239. [PMID: 36399577 PMCID: PMC9674292 DOI: 10.1126/sciadv.adc9239] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Accepted: 10/03/2022] [Indexed: 07/20/2023]
Abstract
According to the cellular actin dynamics paradigm, filaments grow at their barbed ends and depolymerize predominantly from their pointed ends to form polar structures and do productive work. We show that actin can elongate at the pointed end when assisted by Vibrio VopF/L toxins, which act as processive polymerases. In cells, processively moving VopF/L speckles are inhibited by factors blocking the pointed but not barbed ends. Multispectral single-molecule imaging confirmed that VopF molecules associate with the pointed end, actively promoting its elongation even in the presence of profilin. Consequently, VopF/L can break the actin cytoskeleton's polarity by compromising actin-based cellular processes. Therefore, actin filament design allows processive growth at both ends, which suggests unforeseen possibilities for cellular actin organization, particularly in specialized cells and compartments.
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Affiliation(s)
- Elena Kudryashova
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
| | - Ankita
- Department of Physics, Emory University, Atlanta, GA 30322, USA
- Department of Cell Biology, Emory University, Atlanta, GA 30322, USA
| | - Heidi Ulrichs
- Department of Physics, Emory University, Atlanta, GA 30322, USA
- Department of Cell Biology, Emory University, Atlanta, GA 30322, USA
| | - Shashank Shekhar
- Department of Physics, Emory University, Atlanta, GA 30322, USA
- Department of Cell Biology, Emory University, Atlanta, GA 30322, USA
| | - Dmitri S. Kudryashov
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA
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8
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Dong S, Zheng W, Pinkerton N, Hansen J, Tikunova SB, Davis JP, Heissler SM, Kudryashova E, Egelman EH, Kudryashov DS. Photorhabdus luminescens TccC3 Toxin Targets the Dynamic Population of F-Actin and Impairs Cell Cortex Integrity. Int J Mol Sci 2022; 23:7026. [PMID: 35806028 PMCID: PMC9266650 DOI: 10.3390/ijms23137026] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 06/17/2022] [Accepted: 06/22/2022] [Indexed: 12/30/2022] Open
Abstract
Due to its essential role in cellular processes, actin is a common target for bacterial toxins. One such toxin, TccC3, is an effector domain of the ABC-toxin produced by entomopathogenic bacteria of Photorhabdus spp. Unlike other actin-targeting toxins, TccC3 uniquely ADP-ribosylates actin at Thr-148, resulting in the formation of actin aggregates and inhibition of phagocytosis. It has been shown that the fully modified F-actin is resistant to depolymerization by cofilin and gelsolin, but their effects on partially modified actin were not explored. We found that only F-actin unprotected by tropomyosin is the physiological TccC3 substrate. Yet, ADP-ribosylated G-actin can be produced upon cofilin-accelerated F-actin depolymerization, which was only mildly inhibited in partially modified actin. The affinity of TccC3-ADP-ribosylated G-actin for profilin and thymosin-β4 was weakened moderately but sufficiently to potentiate spontaneous polymerization in their presence. Interestingly, the Arp2/3-mediated nucleation was also potentiated by T148-ADP-ribosylation. Notably, even partially modified actin showed reduced bundling by plastins and α-actinin. In agreement with the role of these and other tandem calponin-homology domain actin organizers in the assembly of the cortical actin network, TccC3 induced intense membrane blebbing in cultured cells. Overall, our data suggest that TccC3 imposes a complex action on the cytoskeleton by affecting F-actin nucleation, recycling, and interaction with actin-binding proteins involved in the integration of actin filaments with each other and cellular elements.
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Affiliation(s)
- Songyu Dong
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA; (S.D.); (N.P.); (J.H.); (E.K.)
- The Ohio State Biochemistry Program, The Ohio State University, Columbus, OH 43210, USA
| | - Weili Zheng
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA 22903, USA; (W.Z.); (E.H.E.)
| | - Nicholas Pinkerton
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA; (S.D.); (N.P.); (J.H.); (E.K.)
| | - Jacob Hansen
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA; (S.D.); (N.P.); (J.H.); (E.K.)
| | - Svetlana B. Tikunova
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH 43210, USA; (S.B.T.); (J.P.D.); (S.M.H.)
| | - Jonathan P. Davis
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH 43210, USA; (S.B.T.); (J.P.D.); (S.M.H.)
| | - Sarah M. Heissler
- Department of Physiology and Cell Biology, Davis Heart and Lung Research Institute, The Ohio State University, Columbus, OH 43210, USA; (S.B.T.); (J.P.D.); (S.M.H.)
| | - Elena Kudryashova
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA; (S.D.); (N.P.); (J.H.); (E.K.)
| | - Edward H. Egelman
- Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA 22903, USA; (W.Z.); (E.H.E.)
| | - Dmitri S. Kudryashov
- Department of Chemistry and Biochemistry, The Ohio State University, Columbus, OH 43210, USA; (S.D.); (N.P.); (J.H.); (E.K.)
- The Ohio State Biochemistry Program, The Ohio State University, Columbus, OH 43210, USA
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9
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Jung G, Pan M, Alexander C, Jin T, Hammer JA. Dual regulation of the actin cytoskeleton by CARMIL-GAP. J Cell Sci 2022; 135:275754. [PMID: 35583107 PMCID: PMC9270954 DOI: 10.1242/jcs.258704] [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: 03/27/2021] [Accepted: 05/09/2022] [Indexed: 11/29/2022] Open
Abstract
Capping protein Arp2/3 myosin I linker (CARMIL) proteins are multi-domain scaffold proteins that regulate actin dynamics by regulating the activity of capping protein (CP). Here, we characterize CARMIL-GAP (GAP for GTPase-activating protein), a Dictyostelium CARMIL isoform that contains a ∼130 residue insert that, by homology, confers GTPase-activating properties for Rho-related GTPases. Consistent with this idea, this GAP domain binds Dictyostelium Rac1a and accelerates its rate of GTP hydrolysis. CARMIL-GAP concentrates with F-actin in phagocytic cups and at the leading edge of chemotaxing cells, and CARMIL-GAP-null cells exhibit pronounced defects in phagocytosis and chemotactic streaming. Importantly, these defects are fully rescued by expressing GFP-tagged CARMIL-GAP in CARMIL-GAP-null cells. Finally, rescue with versions of CARMIL-GAP that lack either GAP activity or the ability to regulate CP show that, although both activities contribute significantly to CARMIL-GAP function, the GAP activity plays the bigger role. Together, our results add to the growing evidence that CARMIL proteins influence actin dynamics by regulating signaling molecules as well as CP, and that the continuous cycling of the nucleotide state of Rho GTPases is often required to drive Rho-dependent biological processes. Summary:Dictyostelium CARMIL-GAP supports phagocytosis and chemotaxis by regulating both capping protein and Rac1.
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Affiliation(s)
- Goeh Jung
- Cell and Developmental Biology Center, National Heart lung and Blood Institute, National Institutes of Health, USA
| | - Miao Pan
- Chemotaxis Signal Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Disease, National Institutes of Health, USA
| | - Chris Alexander
- Cell and Developmental Biology Center, National Heart lung and Blood Institute, National Institutes of Health, USA
| | - Tian Jin
- Chemotaxis Signal Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Disease, National Institutes of Health, USA
| | - John A Hammer
- Cell and Developmental Biology Center, National Heart lung and Blood Institute, National Institutes of Health, USA
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10
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Stark BC, Gao Y, Sepich DS, Belk L, Culver MA, Hu B, Mekel M, Ferris W, Shin J, Solnica-Krezel L, Lin F, Cooper JA. CARMIL3 is important for cell migration and morphogenesis during early development in zebrafish. Dev Biol 2022; 481:148-159. [PMID: 34599906 PMCID: PMC8781030 DOI: 10.1016/j.ydbio.2021.09.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 09/21/2021] [Accepted: 09/24/2021] [Indexed: 01/03/2023]
Abstract
Cell migration is important during early animal embryogenesis. Cell migration and cell shape are controlled by actin assembly and dynamics, which depend on capping proteins, including the barbed-end heterodimeric actin capping protein (CP). CP activity can be regulated by capping-protein-interacting (CPI) motif proteins, including CARMIL (capping protein Arp2/3 myosin-I linker) family proteins. Previous studies of CARMIL3, one of the three highly conserved CARMIL genes in vertebrates, have largely been limited to cells in culture. Towards understanding CARMIL function during embryogenesis in vivo, we analyzed zebrafish lines carrying mutations of carmil3. Maternal-zygotic mutants showed impaired endodermal migration during gastrulation, along with defects in dorsal forerunner cell (DFC) cluster formation, which affected the morphogenesis of Kupffer's vesicle (KV). Mutant KVs were smaller, contained fewer cells and displayed decreased numbers of cilia, leading to defects in left/right (L/R) patterning with variable penetrance and expressivity. The penetrance and expressivity of the KV phenotype in carmil3 mutants correlated well with the L/R heart positioning defect at the end of embryogenesis. This in vivo animal study of CARMIL3 reveals its new role during morphogenesis of the vertebrate embryo. This role involves migration of endodermal cells and DFCs, along with subsequent morphogenesis of the KV and L/R asymmetry.
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Affiliation(s)
- Benjamin C. Stark
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St Louis, MO
| | - Yuanyuan Gao
- Department of Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, Iowa City, IA
| | - Diane S. Sepich
- Department of Developmental Biology, Washington University School of Medicine, St Louis, MO
| | - Lakyn Belk
- Department of Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, Iowa City, IA
| | - Matthew A. Culver
- Department of Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, Iowa City, IA
| | - Bo Hu
- Department of Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, Iowa City, IA
| | - Marlene Mekel
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St Louis, MO
| | - Wyndham Ferris
- Department of Developmental Biology, Washington University School of Medicine, St Louis, MO
| | - Jimann Shin
- Department of Developmental Biology, Washington University School of Medicine, St Louis, MO
| | - Lilianna Solnica-Krezel
- Department of Developmental Biology, Washington University School of Medicine, St Louis, MO,Corresponding authors. Email addresses for correspondence after publication: Fang Lin, ; Lilianna Solnica-Krezel, ; John Cooper,
| | - Fang Lin
- Department of Anatomy and Cell Biology, Carver College of Medicine, University of Iowa, Iowa City, IA.,Corresponding authors. Email addresses for correspondence after publication: Fang Lin, ; Lilianna Solnica-Krezel, ; John Cooper,
| | - John A. Cooper
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St Louis, MO,Department of Cell Biology and Physiology, Washington University School of Medicine, St Louis, MO,Corresponding authors. Email addresses for correspondence after publication: Fang Lin, ; Lilianna Solnica-Krezel, ; John Cooper,
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11
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Lamb AK, Fernandez AN, Peersen OB, Di Pietro SM. The dynein light chain protein Tda2 functions as a dimerization engine to regulate actin capping protein during endocytosis. Mol Biol Cell 2021; 32:1459-1473. [PMID: 34081539 PMCID: PMC8351736 DOI: 10.1091/mbc.e21-01-0032] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Clathrin- and actin-mediated endocytosis is a fundamental process in eukaryotic cells. Previously, we discovered Tda2 as a new yeast dynein light chain (DLC) that works with Aim21 to regulate actin assembly during endocytosis. Here we show Tda2 functions as a dimerization engine bringing two Aim21 molecules together using a novel binding surface different than the canonical DLC ligand binding groove. Point mutations on either protein that diminish the Tda2-Aim21 interaction in vitro cause the same in vivo phenotype as TDA2 deletion showing reduced actin capping protein (CP) recruitment and increased filamentous actin at endocytic sites. Remarkably, chemically induced dimerization of Aim21 rescues the endocytic phenotype of TDA2 deletion. We also uncovered a CP interacting motif in Aim21, expanding its function to a fundamental cellular pathway and showing such motif exists outside mammalian cells. Furthermore, specific disruption of this motif causes the same deficit of actin CP recruitment and increased filamentous actin at endocytic sites as AIM21 deletion. Thus, the data indicate the Tda2-Aim21 complex functions in actin assembly primarily through CP regulation. Collectively, our results provide a mechanistic view of the Tda2-Aim21 complex and its function in actin network regulation at endocytic sites.
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Affiliation(s)
- Andrew K Lamb
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523-1870
| | - Andres N Fernandez
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523-1870
| | - Olve B Peersen
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523-1870
| | - Santiago M Di Pietro
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523-1870
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12
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Takeda S, Koike R, Fujiwara I, Narita A, Miyata M, Ota M, Maéda Y. Structural Insights into the Regulation of Actin Capping Protein by Twinfilin C-terminal Tail. J Mol Biol 2021; 433:166891. [PMID: 33639213 DOI: 10.1016/j.jmb.2021.166891] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 02/17/2021] [Accepted: 02/17/2021] [Indexed: 12/19/2022]
Abstract
Twinfilin is a conserved actin regulator that interacts with actin capping protein (CP) via C terminus residues (TWtail) that exhibits sequence similarity with the CP interaction (CPI) motif of CARMIL. Here we report the crystal structure of TWtail in complex with CP. Our structure showed that although TWtail and CARMIL CPI bind CP to an overlapping surface via their middle regions, they exhibit different CP-binding modes at both termini. Consequently, TWtail and CARMIL CPI restrict the CP in distinct conformations of open and closed forms, respectively. Interestingly, V-1, which targets CP away from the TWtail binding site, also favors the open-form CP. Consistently, TWtail forms a stable ternary complex with CP and V-1, a striking contrast to CARMIL CPI, which rapidly dissociates V-1 from CP. Our results demonstrate that TWtail is a unique CP-binding motif that regulates CP in a manner distinct from CARMIL CPI.
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Affiliation(s)
- Shuichi Takeda
- Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602, Japan.
| | - Ryotaro Koike
- Graduate School of Informatics, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Ikuko Fujiwara
- Graduate School of Science, Osaka City University, Osaka, Osaka 558-8585, Japan
| | - Akihiro Narita
- Graduate School of Science, Nagoya University, Nagoya, Aichi 464-8602, Japan
| | - Makoto Miyata
- Graduate School of Science, Osaka City University, Osaka, Osaka 558-8585, Japan; The OCU Advanced Research Institute for Natural Science and Technology (OCARINA), Osaka City University, Osaka, Osaka 558-8585, Japan
| | - Motonori Ota
- Graduate School of Informatics, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Yuichiro Maéda
- Graduate School of Informatics, Nagoya University, Nagoya, Aichi 464-8601, Japan
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13
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Ghode A, Gross LZF, Tee WV, Guarnera E, Berezovsky IN, Biondi RM, Anand GS. Synergistic Allostery in Multiligand-Protein Interactions. Biophys J 2020; 119:1833-1848. [PMID: 33086047 PMCID: PMC7677135 DOI: 10.1016/j.bpj.2020.09.019] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Revised: 08/31/2020] [Accepted: 09/15/2020] [Indexed: 02/07/2023] Open
Abstract
Amide hydrogen-deuterium exchange mass spectrometry is powerful for describing combinatorial coupling effects of a cooperative ligand pair binding at noncontiguous sites: adenosine at the ATP-pocket and a docking peptide (PIFtide) at the PIF-pocket, on a model protein kinase PDK1. Binding of two ligands to PDK1 reveal multiple hotspots of synergistic allostery with cumulative effects greater than the sum of individual effects mediated by each ligand. We quantified this synergism and ranked these hotspots using a difference in deuteration-based approach, which showed that the strongest synergistic effects were observed at three of the critical catalytic loci of kinases: the αB-αC helices, and HRD-motif loop, and DFG-motif. Additionally, we observed weaker synergistic effects at a distal GHI-subdomain locus. Synergistic changes in deuterium exchange observed at a distal site but not at the intermediate sites of the large lobe of the kinase reveals allosteric propagation in proteins to operate through two modes. Direct electrostatic interactions between polar and charged amino acids that mediate targeted relay of allosteric signals, and diffused relay of allosteric signals through soft matter-like hydrophobic core amino acids. Furthermore, we provide evidence that the conserved β-3 strand lysine of protein kinases (Lys111 of PDK1) functions as an integrator node to coordinate allosteric coupling of the two ligand-binding sites. It maintains indirect interactions with the ATP-pocket and mediates a critical salt bridge with a glutamate (Glu130) of αC helix, which is conserved across all kinases. In summary, allosteric propagation in cooperative, dual-liganded enzyme targets is bidirectional and synergistic and offers a strategy for combinatorial drug development.
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Affiliation(s)
- Abhijeet Ghode
- Department of Biological Sciences, National University of Singapore, Singapore
| | - Lissy Z F Gross
- Instituto de Investigación en Biomedicina de Buenos Aires - CONICET - Partner Institute of the Max Planck Society, Buenos Aires, Argentina
| | - Wei-Ven Tee
- Department of Biological Sciences, National University of Singapore, Singapore; Bioinformatics Institute, Agency for Science, Technology and Research, Matrix, Singapore
| | - Enrico Guarnera
- Bioinformatics Institute, Agency for Science, Technology and Research, Matrix, Singapore
| | - Igor N Berezovsky
- Department of Biological Sciences, National University of Singapore, Singapore; Bioinformatics Institute, Agency for Science, Technology and Research, Matrix, Singapore
| | - Ricardo M Biondi
- Instituto de Investigación en Biomedicina de Buenos Aires - CONICET - Partner Institute of the Max Planck Society, Buenos Aires, Argentina
| | - Ganesh S Anand
- Department of Biological Sciences, National University of Singapore, Singapore.
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14
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McConnell P, Mekel M, Kozlov AG, Mooren OL, Lohman TM, Cooper JA. Comparative Analysis of CPI-Motif Regulation of Biochemical Functions of Actin Capping Protein. Biochemistry 2020; 59:1202-1215. [PMID: 32133840 DOI: 10.1021/acs.biochem.0c00092] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The heterodimeric actin capping protein (CP) is regulated by a set of proteins that contain CP-interacting (CPI) motifs. Outside of the CPI motif, the sequences of these proteins are unrelated and distinct. The CPI motif and surrounding sequences are conserved within a given protein family, when compared to those of other CPI-motif protein families. Using biochemical assays with purified proteins, we compared the ability of CPI-motif-containing peptides from different protein families (a) to bind to CP, (b) to allosterically inhibit barbed-end capping by CP, and (c) to allosterically inhibit interaction of CP with V-1, another regulator of CP. We found large differences in potency among the different CPI-motif-containing peptides, and the different functional assays showed different orders of potency. These biochemical differences among the CPI-motif peptides presumably reflect interactions between CP and CPI-motif peptides involving amino acid residues that are conserved but are not part of the strictly defined consensus, as it was originally identified in comparisons of sequences of CPI motifs across all protein families [Hernandez-Valladares, M., et al. (2010) Structural characterization of a capping protein interaction motif defines a family of actin filament regulators. Nat. Struct. Mol. Biol. 17, 497-503; Bruck, S., et al. (2006) Identification of a Novel Inhibitory Actin-capping Protein Binding Motif in CD2-associated Protein. J. Biol. Chem. 281, 19196-19203]. These biochemical differences may be important for conserved distinct functions of CPI-motif protein families in cells with respect to the regulation of CP activity and actin assembly near membranes.
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Affiliation(s)
- Patrick McConnell
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Marlene Mekel
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Alexander G Kozlov
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Olivia L Mooren
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - Timothy M Lohman
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110, United States
| | - John A Cooper
- Department of Biochemistry and Molecular Biophysics, Washington University School of Medicine, St. Louis, Missouri 63110, United States
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15
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Wang H, Wang C, Peng G, Yu D, Cui XG, Sun YH, Ma X. Capping Protein Regulator and Myosin 1 Linker 3 Is Required for Tumor Metastasis. Mol Cancer Res 2019; 18:240-252. [PMID: 31694931 DOI: 10.1158/1541-7786.mcr-19-0722] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2019] [Revised: 08/27/2019] [Accepted: 11/01/2019] [Indexed: 11/16/2022]
Affiliation(s)
- Huan Wang
- State Key Laboratory of Microbial Metabolism, Sheng Yushou Center of Cell Biology and Immunology, School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Chao Wang
- Department of Urology, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Guang Peng
- Department of Urology, Changhai Hospital, Second Military Medical University, Shanghai, China
| | - Doudou Yu
- State Key Laboratory of Microbial Metabolism, Sheng Yushou Center of Cell Biology and Immunology, School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai, China
| | - Xin-Gang Cui
- Department of Urinary Surgery, Gongli Hospital, Shanghai, China.
- Department of Urinary Surgery, The Third Affiliated Hospital (Eastern Hepatobiliary Surgery Hospital), Second Military Medical University, Shanghai, China
| | - Ying-Hao Sun
- Department of Urology, Changhai Hospital, Second Military Medical University, Shanghai, China.
| | - Xiaojing Ma
- State Key Laboratory of Microbial Metabolism, Sheng Yushou Center of Cell Biology and Immunology, School of Life Science and Biotechnology, Shanghai Jiao Tong University, Shanghai, China.
- Department of Microbiology and Immunology, Weill Cornell Medicine, New York, New York
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Chen G, Karauzum H, Long H, Carranza D, Holtsberg FW, Howell KA, Abaandou L, Zhang B, Jarvik N, Ye W, Liao GC, Gross ML, Leung DW, Amarasinghe GK, Aman MJ, Sidhu SS. Potent Neutralization of Staphylococcal Enterotoxin B In Vivo by Antibodies that Block Binding to the T-Cell Receptor. J Mol Biol 2019; 431:4354-4367. [PMID: 30928493 DOI: 10.1016/j.jmb.2019.03.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2019] [Revised: 03/12/2019] [Accepted: 03/13/2019] [Indexed: 11/15/2022]
Abstract
To develop an antibody (Ab) therapeutic against staphylococcal enterotoxin B (SEB), a potential incapacitating bioterrorism agent and a major cause of food poisoning, we developed a "class T" anti-SEB neutralizing Ab (GC132) targeting an epitope on SEB distinct from that of previously developed "class M" Abs. A systematic engineering approach was applied to affinity-mature Ab GC132 to yield an optimized therapeutic candidate (GC132a) with sub-nanomolar binding affinity. Mapping of the binding interface by hydrogen-deuterium exchange coupled to mass spectrometry revealed that the class T epitope on SEB overlapped with the T-cell receptor binding site, whereas other evidence suggested that the class M epitope overlapped with the binding site for the major histocompatibility complex. In the IgG format, GC132a showed ∼50-fold more potent toxin-neutralizing efficacy than the best class M Ab in vitro, and fully protected mice from lethal challenge in a toxic shock post-exposure model. We also engineered bispecific Abs (bsAbs) that bound tetravalently by utilizing two class M binding sites and two class T binding sites. The bsAbs displayed enhanced toxin neutralization efficacy compared with the respective monospecific Ab subunits as well as a mixture of the two, indicating that enhanced efficacy was due to heterotypic tetravalent binding to two non-overlapping epitopes on SEB. Together, these results suggest that class T anti-SEB Ab GC132a is an excellent candidate for clinical development and for bsAb engineering.
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Affiliation(s)
- Gang Chen
- Banting and Best Department of Medical Research, Department of Molecular Genetics, and the Terrence Donnelly Center for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario M5S 3E1, Canada
| | | | - Hua Long
- Banting and Best Department of Medical Research, Department of Molecular Genetics, and the Terrence Donnelly Center for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario M5S 3E1, Canada
| | - Danielle Carranza
- Banting and Best Department of Medical Research, Department of Molecular Genetics, and the Terrence Donnelly Center for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario M5S 3E1, Canada
| | | | - Katie A Howell
- Integrated Biotherapeutics, Inc., Rockville, MD 20850, USA
| | - Laura Abaandou
- Integrated Biotherapeutics, Inc., Rockville, MD 20850, USA
| | - Bojie Zhang
- Department of Chemistry, Washington University in St. Louis, St Louis, MO 63130, USA
| | - Nick Jarvik
- Banting and Best Department of Medical Research, Department of Molecular Genetics, and the Terrence Donnelly Center for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario M5S 3E1, Canada
| | - Wei Ye
- Banting and Best Department of Medical Research, Department of Molecular Genetics, and the Terrence Donnelly Center for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario M5S 3E1, Canada
| | - Grant C Liao
- Integrated Biotherapeutics, Inc., Rockville, MD 20850, USA
| | - Michael L Gross
- Department of Chemistry, Washington University in St. Louis, St Louis, MO 63130, USA; Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Daisy W Leung
- Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - Gaya K Amarasinghe
- Department of Pathology and Immunology, Washington University School of Medicine, St Louis, MO 63110, USA
| | - M Javad Aman
- Integrated Biotherapeutics, Inc., Rockville, MD 20850, USA.
| | - Sachdev S Sidhu
- Banting and Best Department of Medical Research, Department of Molecular Genetics, and the Terrence Donnelly Center for Cellular and Biomolecular Research, University of Toronto, Toronto, Ontario M5S 3E1, Canada.
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17
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Johnston AB, Hilton DM, McConnell P, Johnson B, Harris MT, Simone A, Amarasinghe GK, Cooper JA, Goode BL. A novel mode of capping protein-regulation by twinfilin. eLife 2018; 7:41313. [PMID: 30351272 PMCID: PMC6249002 DOI: 10.7554/elife.41313] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 10/22/2018] [Indexed: 12/29/2022] Open
Abstract
Cellular actin assembly is controlled at the barbed ends of actin filaments, where capping protein (CP) limits polymerization. Twinfilin is a conserved in vivo binding partner of CP, yet the significance of this interaction has remained a mystery. Here, we discover that the C-terminal tail of Twinfilin harbors a CP-interacting (CPI) motif, identifying it as a novel CPI-motif protein. Twinfilin and the CPI-motif protein CARMIL have overlapping binding sites on CP. Further, Twinfilin binds competitively with CARMIL to CP, protecting CP from barbed-end displacement by CARMIL. Twinfilin also accelerates dissociation of the CP inhibitor V-1, restoring CP to an active capping state. Knockdowns of Twinfilin and CP each cause similar defects in cell morphology, and elevated Twinfilin expression rescues defects caused by CARMIL hyperactivity. Together, these observations define Twinfilin as the first ‘pro-capping’ ligand of CP and lead us to propose important revisions to our understanding of the CP regulatory cycle. Plant and animal cells are supported by skeleton-like structures that can grow and shrink beneath the cell membrane, pushing and pulling on the edges of the cell. This scaffolding network – known as the cytoskeleton – contains long strands, or filaments, made from many identical copies of a protein called actin. The shape of the actin proteins allows them to slot together, end-to-end, and allows the strands to grow and shrink on-demand. When the strands are the correct length, the cell caps the growing ends with a protein known as Capping Protein. This helps to stabilize the cell’s skeleton, preventing the strands from getting any longer, or any shorter. Proteins that interfere with the activity of Capping Protein allow the actin strands to grow or shrink. Some, like a protein called V-1, attach to Capping Protein and get in the way so that it cannot sit on the ends of the actin strands. Others, like CARMIL, bind to Capping Protein and change its shape, making it more likely to fall off the strands. So far, no one had found a partner that helps Capping Protein limit the growth of the actin cytoskeleton. A protein called Twinfilin often appears alongside Capping Protein, but the two proteins seemed to have no influence on each other, and had what appeared to be different roles. Whilst Capping Protein blocks growth and stabilizes actin strands, Twinfilin speeds up their disassembly at their ends. But Johnston, Hilton et al. now reveal that the two proteins actually work together. Twinfilin helps Capping Protein resist the effects of CARMIL and V-1, and Capping Protein puts Twinfilin at the end of the strand. Thus, when Capping Protein is finally removed by CARMIL, Twinfilin carries on with disassembling the actin strands. The tail of the Twinfilin protein looks like part of the CARMIL protein, suggesting that they might interact with Capping Protein in the same way. Attaching a fluorescent tag to the Twinfilin tail revealed that the two proteins compete to attach to the same part of the Capping Protein. When mouse cells produced extra Twinfilin, it blocked the effects of CARMIL, helping to grow the actin strands. V-1 attaches to Capping Protein in a different place, but Twinfilin was also able to interfere with its activity. When Twinfilin attached to the CARMIL binding site, it did not directly block V-1 binding, but it made the protein more likely to fall off. Understanding how the actin cytoskeleton moves is a key question in cell biology, but it also has applications in medicine. Twinfilin plays a role in the spread of certain blood cancer cells, and in the formation of elaborate structures in the inner ear that help us hear. Understanding how Twinfilin and Capping Protein interact could open paths to new therapies for a range of medical conditions.
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Affiliation(s)
- Adam B Johnston
- Department of Biology, Rosenstiel Basic Medical Science Research Center, Brandeis University, Waltham, United States
| | - Denise M Hilton
- Department of Biology, Rosenstiel Basic Medical Science Research Center, Brandeis University, Waltham, United States
| | - Patrick McConnell
- Department of Biochemistry and Molecular Biophysics, Washington University, St Louis, United states
| | - Britney Johnson
- Department of Pathology and Immunology, Washington University, St Louis, United States
| | - Meghan T Harris
- Department of Biology, Rosenstiel Basic Medical Science Research Center, Brandeis University, Waltham, United States
| | - Avital Simone
- Department of Biology, Rosenstiel Basic Medical Science Research Center, Brandeis University, Waltham, United States
| | - Gaya K Amarasinghe
- Department of Pathology and Immunology, Washington University, St Louis, United States
| | - John A Cooper
- Department of Biochemistry and Molecular Biophysics, Washington University, St Louis, United states
| | - Bruce L Goode
- Department of Biology, Rosenstiel Basic Medical Science Research Center, Brandeis University, Waltham, United States
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