Academic Journal
Actin filament assembly driven by distributive polymerases clustered on membrane surfaces.
| Τίτλος: | Actin filament assembly driven by distributive polymerases clustered on membrane surfaces. |
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| Συγγραφείς: | Mullins RD; Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA. Electronic address: dyche.mullins@ucsf.edu., Kondev J; Department of Physics, Brandeis University, Waltham, MA, USA., Skruber K; Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA, USA. |
| Πηγή: | Biophysical journal [Biophys J] 2026 Sep 01; Vol. 125 (17), pp. 4809-4827. Date of Electronic Publication: 2026 Aug 05. |
| Τύπος έκδοσης: | Journal Article |
| Γλώσσα: | English |
| Στοιχεία περιοδικού: | Publisher: Cell Press Country of Publication: United States NLM ID: 0370626 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1542-0086 (Electronic) Linking ISSN: 00063495 NLM ISO Abbreviation: Biophys J Subsets: MEDLINE |
| Imprint Name(s): | Publication: Cambridge, MA : Cell Press Original Publication: New York, Published by Rockefeller University Press [etc.] for the Biophysical Society. |
| Ιατρικοί όροι (MeSH): | Actin Cytoskeleton*/metabolism , Actin Cytoskeleton*/chemistry , Cell Membrane*/metabolism , Protein Multimerization*, Profilins/metabolism ; Actins/metabolism ; Surface Properties ; Models, Biological ; Polymerization |
| Περίληψη: | Actin filaments created by the Arp2/3 complex form branched networks that grow and push against cellular membranes. We employ theory and simulation to describe how membrane surfaces accelerate filament assembly via clustering of proteins, including WAVE-family nucleation-promoting factors, that bind actin monomers and/or profilin-actin complexes. Briefly, thermal fluctuations drive filament tips on constrained, two-dimensional random walks across the membrane, where they collide with actin-charged polymerases. At low soluble actin concentrations, filament elongation is limited by delivery of monomers to the membrane surface; at high actin concentrations, elongation depends on how quickly fluctuating filaments search the membrane. Using measured parameter values, we conclude that surface-mediated polymerization can outpace solution-mediated elongation, even at high actin concentrations (>100 μM). The finite time required for profilin dissociation decreases the advantage conferred by surface-associated polymerases but only in the absence of force. Load forces enhance the effect of surface polymerases, which can both accelerate elongation and increase the force required to stall filament assembly. (Copyright © 2026 The Authors. Published by Elsevier Inc. All rights reserved.) |
| Competing Interests: | Declaration of interests The authors declare no competing interests. |
| Σχόλια: | Update of: bioRxiv. 2025 Oct 03:2024.11.26.625540. doi: 10.1101/2024.11.26.625540.. (PMID: 41256648) Erratum in: Biophys J. 2026 Sep 5:S0006-3495(26)00605-3. doi: 10.1016/j.bpj.2026.08.024.. (PMID: 42700770) |
| Substance Nomenclature: | 0 (Profilins) 0 (Actins) |
| Entry Date(s): | Date Created: 20260806 Date Completed: 20260901 Latest Revision: 20260905 |
| Update Code: | 20260906 |
| DOI: | 10.1016/j.bpj.2026.07.027 |
| PMID: | 42557775 |
| Βάση Δεδομένων: | MEDLINE |
| ISSN: | 1542-0086 |
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| DOI: | 10.1016/j.bpj.2026.07.027 |