--- _id: '12421' abstract: - lang: eng text: The actin cytoskeleton plays a key role in cell migration and cellular morphodynamics in most eukaryotes. The ability of the actin cytoskeleton to assemble and disassemble in a spatiotemporally controlled manner allows it to form higher-order structures, which can generate forces required for a cell to explore and navigate through its environment. It is regulated not only via a complex synergistic and competitive interplay between actin-binding proteins (ABP), but also by filament biochemistry and filament geometry. The lack of structural insights into how geometry and ABPs regulate the actin cytoskeleton limits our understanding of the molecular mechanisms that define actin cytoskeleton remodeling and, in turn, impact emerging cell migration characteristics. With the advent of cryo-electron microscopy (cryo-EM) and advanced computational methods, it is now possible to define these molecular mechanisms involving actin and its interactors at both atomic and ultra-structural levels in vitro and in cellulo. In this review, we will provide an overview of the available cryo-EM methods, applicable to further our understanding of the actin cytoskeleton, specifically in the context of cell migration. We will discuss how these methods have been employed to elucidate ABP- and geometry-defined regulatory mechanisms in initiating, maintaining, and disassembling cellular actin networks in migratory protrusions. acknowledgement: 'We apologize for not being able to mention and cite additional excellent work that would have fit the scope of this review, due to space restraints. We thank Jesse Hansen for comments on the manuscript. We acknowledge support from the Austrian Science Fund (FWF): P33367 and the Institute of Science and Technology Austria.' article_processing_charge: No article_type: original author: - first_name: Florian full_name: Fäßler, Florian id: 404F5528-F248-11E8-B48F-1D18A9856A87 last_name: Fäßler orcid: 0000-0001-7149-769X - first_name: Manjunath full_name: Javoor, Manjunath id: 305ab18b-dc7d-11ea-9b2f-b58195228ea2 last_name: Javoor - first_name: Florian KM full_name: Schur, Florian KM id: 48AD8942-F248-11E8-B48F-1D18A9856A87 last_name: Schur orcid: 0000-0003-4790-8078 citation: ama: Fäßler F, Javoor M, Schur FK. Deciphering the molecular mechanisms of actin cytoskeleton regulation in cell migration using cryo-EM. Biochemical Society Transactions. 2023;51(1):87-99. doi:10.1042/bst20220221 apa: Fäßler, F., Javoor, M., & Schur, F. K. (2023). Deciphering the molecular mechanisms of actin cytoskeleton regulation in cell migration using cryo-EM. Biochemical Society Transactions. Portland Press. https://doi.org/10.1042/bst20220221 chicago: Fäßler, Florian, Manjunath Javoor, and Florian KM Schur. “Deciphering the Molecular Mechanisms of Actin Cytoskeleton Regulation in Cell Migration Using Cryo-EM.” Biochemical Society Transactions. Portland Press, 2023. https://doi.org/10.1042/bst20220221. ieee: F. Fäßler, M. Javoor, and F. K. Schur, “Deciphering the molecular mechanisms of actin cytoskeleton regulation in cell migration using cryo-EM,” Biochemical Society Transactions, vol. 51, no. 1. Portland Press, pp. 87–99, 2023. ista: Fäßler F, Javoor M, Schur FK. 2023. Deciphering the molecular mechanisms of actin cytoskeleton regulation in cell migration using cryo-EM. Biochemical Society Transactions. 51(1), 87–99. mla: Fäßler, Florian, et al. “Deciphering the Molecular Mechanisms of Actin Cytoskeleton Regulation in Cell Migration Using Cryo-EM.” Biochemical Society Transactions, vol. 51, no. 1, Portland Press, 2023, pp. 87–99, doi:10.1042/bst20220221. short: F. Fäßler, M. Javoor, F.K. Schur, Biochemical Society Transactions 51 (2023) 87–99. date_created: 2023-01-27T10:08:19Z date_published: 2023-02-01T00:00:00Z date_updated: 2023-08-01T12:55:32Z day: '01' ddc: - '570' department: - _id: FlSc doi: 10.1042/bst20220221 external_id: isi: - '000926043100001' file: - access_level: open_access checksum: 4e7069845e3dad22bb44fb71ec624c60 content_type: application/pdf creator: dernst date_created: 2023-03-16T07:58:16Z date_updated: 2023-03-16T07:58:16Z file_id: '12728' file_name: 2023_BioChemicalSocietyTransactions_Faessler.pdf file_size: 10045006 relation: main_file success: 1 file_date_updated: 2023-03-16T07:58:16Z has_accepted_license: '1' intvolume: ' 51' isi: 1 issue: '1' keyword: - Biochemistry language: - iso: eng month: '02' oa: 1 oa_version: Published Version page: 87-99 project: - _id: 9B954C5C-BA93-11EA-9121-9846C619BF3A grant_number: P33367 name: Structure and isoform diversity of the Arp2/3 complex publication: Biochemical Society Transactions publication_identifier: eissn: - 1470-8752 issn: - 0300-5127 publication_status: published publisher: Portland Press quality_controlled: '1' scopus_import: '1' status: public title: Deciphering the molecular mechanisms of actin cytoskeleton regulation in cell migration using cryo-EM tmp: image: /images/cc_by.png legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0) short: CC BY (4.0) type: journal_article user_id: 4359f0d1-fa6c-11eb-b949-802e58b17ae8 volume: 51 year: '2023' ... --- _id: '12334' abstract: - lang: eng text: Regulation of the Arp2/3 complex is required for productive nucleation of branched actin networks. An emerging aspect of regulation is the incorporation of subunit isoforms into the Arp2/3 complex. Specifically, both ArpC5 subunit isoforms, ArpC5 and ArpC5L, have been reported to fine-tune nucleation activity and branch junction stability. We have combined reverse genetics and cellular structural biology to describe how ArpC5 and ArpC5L differentially affect cell migration. Both define the structural stability of ArpC1 in branch junctions and, in turn, by determining protrusion characteristics, affect protein dynamics and actin network ultrastructure. ArpC5 isoforms also affect the positioning of members of the Ena/Vasodilator-stimulated phosphoprotein (VASP) family of actin filament elongators, which mediate ArpC5 isoform–specific effects on the actin assembly level. Our results suggest that ArpC5 and Ena/VASP proteins are part of a signaling pathway enhancing cell migration. acknowledged_ssus: - _id: ScienComp - _id: LifeSc - _id: Bio - _id: EM-Fac acknowledgement: "We would like to thank K. von Peinen and B. Denker (Helmholtz Centre for Infection Research, Braunschweig, Germany) for experimental and technical assistance, respectively.\r\nThis research was supported by the Scientific Service Units (SSUs) of ISTA through resources provided by Scientific Computing (SciComp), the Life Science Facility (LSF), the Imaging and Optics facility (IOF), and the Electron Microscopy Facility (EMF). We acknowledge support from ISTA and from the Austrian Science Fund (FWF) (P33367) to F.K.M.S., from the Research Training Group GRK2223 and the Helmholtz Society to K.R,. and from the Deutsche Forschungsgemeinschaft (DFG) to J.F. and K.R." article_number: add6495 article_processing_charge: No article_type: original author: - first_name: Florian full_name: Fäßler, Florian id: 404F5528-F248-11E8-B48F-1D18A9856A87 last_name: Fäßler orcid: 0000-0001-7149-769X - first_name: Manjunath full_name: Javoor, Manjunath id: 305ab18b-dc7d-11ea-9b2f-b58195228ea2 last_name: Javoor - first_name: Julia full_name: Datler, Julia id: 3B12E2E6-F248-11E8-B48F-1D18A9856A87 last_name: Datler orcid: 0000-0002-3616-8580 - first_name: Hermann full_name: Döring, Hermann last_name: Döring - first_name: Florian full_name: Hofer, Florian id: b9d234ba-9e33-11ed-95b6-cd561df280e6 last_name: Hofer - first_name: Georgi A full_name: Dimchev, Georgi A id: 38C393BE-F248-11E8-B48F-1D18A9856A87 last_name: Dimchev orcid: 0000-0001-8370-6161 - first_name: Victor-Valentin full_name: Hodirnau, Victor-Valentin id: 3661B498-F248-11E8-B48F-1D18A9856A87 last_name: Hodirnau - first_name: Jan full_name: Faix, Jan last_name: Faix - first_name: Klemens full_name: Rottner, Klemens last_name: Rottner - first_name: Florian KM full_name: Schur, Florian KM id: 48AD8942-F248-11E8-B48F-1D18A9856A87 last_name: Schur orcid: 0000-0003-4790-8078 citation: ama: Fäßler F, Javoor M, Datler J, et al. ArpC5 isoforms regulate Arp2/3 complex–dependent protrusion through differential Ena/VASP positioning. Science Advances. 2023;9(3). doi:10.1126/sciadv.add6495 apa: Fäßler, F., Javoor, M., Datler, J., Döring, H., Hofer, F., Dimchev, G. A., … Schur, F. K. (2023). ArpC5 isoforms regulate Arp2/3 complex–dependent protrusion through differential Ena/VASP positioning. Science Advances. American Association for the Advancement of Science. https://doi.org/10.1126/sciadv.add6495 chicago: Fäßler, Florian, Manjunath Javoor, Julia Datler, Hermann Döring, Florian Hofer, Georgi A Dimchev, Victor-Valentin Hodirnau, Jan Faix, Klemens Rottner, and Florian KM Schur. “ArpC5 Isoforms Regulate Arp2/3 Complex–Dependent Protrusion through Differential Ena/VASP Positioning.” Science Advances. American Association for the Advancement of Science, 2023. https://doi.org/10.1126/sciadv.add6495. ieee: F. Fäßler et al., “ArpC5 isoforms regulate Arp2/3 complex–dependent protrusion through differential Ena/VASP positioning,” Science Advances, vol. 9, no. 3. American Association for the Advancement of Science, 2023. ista: Fäßler F, Javoor M, Datler J, Döring H, Hofer F, Dimchev GA, Hodirnau V-V, Faix J, Rottner K, Schur FK. 2023. ArpC5 isoforms regulate Arp2/3 complex–dependent protrusion through differential Ena/VASP positioning. Science Advances. 9(3), add6495. mla: Fäßler, Florian, et al. “ArpC5 Isoforms Regulate Arp2/3 Complex–Dependent Protrusion through Differential Ena/VASP Positioning.” Science Advances, vol. 9, no. 3, add6495, American Association for the Advancement of Science, 2023, doi:10.1126/sciadv.add6495. short: F. Fäßler, M. Javoor, J. Datler, H. Döring, F. Hofer, G.A. Dimchev, V.-V. Hodirnau, J. Faix, K. Rottner, F.K. Schur, Science Advances 9 (2023). date_created: 2023-01-23T07:26:42Z date_published: 2023-01-20T00:00:00Z date_updated: 2023-11-21T08:05:35Z day: '20' ddc: - '570' department: - _id: FlSc - _id: EM-Fac doi: 10.1126/sciadv.add6495 external_id: isi: - '000964550100015' file: - access_level: open_access checksum: ce81a6d0b84170e5e8c62f6acfa15d9e content_type: application/pdf creator: dernst date_created: 2023-01-23T07:45:54Z date_updated: 2023-01-23T07:45:54Z file_id: '12335' file_name: 2023_ScienceAdvances_Faessler.pdf file_size: 1756234 relation: main_file success: 1 file_date_updated: 2023-01-23T07:45:54Z has_accepted_license: '1' intvolume: ' 9' isi: 1 issue: '3' keyword: - Multidisciplinary language: - iso: eng month: '01' oa: 1 oa_version: Published Version project: - _id: 9B954C5C-BA93-11EA-9121-9846C619BF3A grant_number: P33367 name: Structure and isoform diversity of the Arp2/3 complex publication: Science Advances publication_identifier: issn: - 2375-2548 publication_status: published publisher: American Association for the Advancement of Science quality_controlled: '1' related_material: record: - id: '14562' relation: research_data status: public scopus_import: '1' status: public title: ArpC5 isoforms regulate Arp2/3 complex–dependent protrusion through differential Ena/VASP positioning tmp: image: /images/cc_by.png legal_code_url: https://creativecommons.org/licenses/by/4.0/legalcode name: Creative Commons Attribution 4.0 International Public License (CC-BY 4.0) short: CC BY (4.0) type: journal_article user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87 volume: 9 year: '2023' ...