Continuous self-repair protects vimentin intermediate filaments from fragmentation DOI Creative Commons
Quang D. Tran, Martin Lenz, Hugo Wioland

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 3, 2024

Abstract Intermediate filaments are key regulators of cell mechanics. Vimentin, a type intermediate filament expressed in mesenchymal cells and involved migration, forms dense network the cytoplasm that is constantly remodeled through transport, elongation/shortening, subunit exchange. While it known elongation involves end-to-end annealing, unclear how reverse process shortening by fragmentation occurs. Here, we use combination vitro reconstitution probed fluorescence imaging theoretical modeling to uncover molecular mechanism breakage. We first show vimentin composed two layers subunits, half which exchangeable immobile. also subunits tetramers. further reveal continuous self-repair soluble pool tetramers equilibrium with essential maintain integrity. Filaments break as consequence local fluctuations number per cross-section induced constant exchange determine tends if about four removed from same cross-section. Finally, analyze dynamics association/dissociation estimate binding energy tetramer complete versus partially disassembled filament. Our results provide comprehensive description turnover link between fragmentation. SIGNIFICANCE STATEMENT filaments, including vimentin, component cytoskeleton, for Inside cell, fulfill its functions. In particular, elongate fragment, but this breakage was unknown. Here along length, could locally weaken physical understanding mechanisms regulating feature determining dynamic organization both healthy diseased assembly disrupted.

Language: Английский

Vimentin undergoes liquid–liquid phase separation to form droplets which wet and stabilize actin fibers DOI Creative Commons
Arkaprabha Basu,

Tommy J. Krug,

Benjamin du Pont

et al.

Proceedings of the National Academy of Sciences, Journal Year: 2025, Volume and Issue: 122(10)

Published: March 3, 2025

The cytoskeleton is composed of F-actin, microtubules, and intermediate filaments (IFs). Vimentin one the most ubiquitous well-studied IFs. It involved in many activities including wound healing, tissue fibrosis, cancer metastasis, all which require rapid vimentin IF assembly. In this paper, we report that forms liquid condensates appear to enable filament growth. Given transient nature these droplets, focus on properties vimentin-Y117L, has a point mutation leads formation but not IFs, enabling us study droplets detail. dissolve under 1,6-Hexanediol treatment decreasing concentration, confirming they are liquid, phase separated. These extensively wet actin stress fibers, rendering them resistant actin-binding drugs protecting from depolymerization. We show similar behavior occurs wild-type during its assembly into filaments.

Language: Английский

Citations

1
Versatility of vimentin assemblies: from filaments to biomolecular condensates and back DOI Creative Commons
Dolores Pérez‐Sala, Silvia Zorrilla

European Journal of Cell Biology, Journal Year: 2025, Volume and Issue: unknown, P. 151487 - 151487

Published: April 1, 2025

Language: Английский

Citations

0
Learning physics and biology from cytoskeletal and condensate interactions DOI Creative Commons

Julia F. Bourdeau,

Prashali Chauhan, Jennifer L. Ross

et al.

Current Opinion in Cell Biology, Journal Year: 2025, Volume and Issue: 94, P. 102506 - 102506

Published: April 6, 2025

Two important mechanisms for self-organization in cells include condensation of biomolecules, such as proteins and nucleic acids into phase-separated droplets to form membraneless organelles organization the cytoskeletal filaments larger-scale systems actin cortex microtubule-based mitotic spindle. Recent publications highlight that these two intracellular schemes are coordinated, with condensates controlling organizations cytoskeleton organizing condensates. Here, we focus on recent progress from past 2 years at interface between cytoskeleton. We split discussion physical biological principles can learn studies.

Language: Английский

Citations

0
Enhancing oxidative tolerance and fermentation performance of Lactobacillus casei through adaptive laboratory evolution DOI Creative Commons
Lei Su, Shan Li,

Xindong Li

et al.

LWT, Journal Year: 2025, Volume and Issue: unknown, P. 117826 - 117826

Published: April 1, 2025

Language: Английский

Citations

0
FilaBuster: A Strategy for Rapid, Specific, and Spatiotemporally Controlled Intermediate Filament Disassembly DOI Creative Commons

A. T. Moore,

Tommy J. Krug,

Simon B. Hansen

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown

Published: April 21, 2025

Abstract Intermediate filaments (IFs) play key roles in cellular mechanics, signaling, and organization, but tools for their rapid, selective disassembly remain limited. Here, we introduce FilaBuster, a photochemical approach efficient spatiotemporally controlled IF living cells. FilaBuster uses three-step strategy: (1) targeting HaloTag to IFs, (2) labeling with covalent photosensitizer ligand, (3) light-induced generation of localized reactive oxygen species trigger filament disassembly. This modular strategy applies broadly across subtypes—including vimentin, GFAP, desmin, peripherin, keratin 18—and is compatible diverse dyes imaging platforms. Using vimentin IFs as model system, establish baseline implementation which vimentin-HaloTag labeled ligand triggers rapid specific upon light activation. We then refine this by (i) expanding strategies include nanobody-HaloTag fusion, (ii) broadening the range effective photosensitizers, (iii) optimizing irradiation parameters enable precise spatial control over Together, these findings position robust platform acute, selective, networks, enabling new investigations into structural functional cell physiology disease.

Language: Английский

Citations

0
Continuous self-repair protects vimentin intermediate filaments from fragmentation DOI Creative Commons
Quang D. Tran, Martin Lenz, Hugo Wioland

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 3, 2024

Abstract Intermediate filaments are key regulators of cell mechanics. Vimentin, a type intermediate filament expressed in mesenchymal cells and involved migration, forms dense network the cytoplasm that is constantly remodeled through transport, elongation/shortening, subunit exchange. While it known elongation involves end-to-end annealing, unclear how reverse process shortening by fragmentation occurs. Here, we use combination vitro reconstitution probed fluorescence imaging theoretical modeling to uncover molecular mechanism breakage. We first show vimentin composed two layers subunits, half which exchangeable immobile. also subunits tetramers. further reveal continuous self-repair soluble pool tetramers equilibrium with essential maintain integrity. Filaments break as consequence local fluctuations number per cross-section induced constant exchange determine tends if about four removed from same cross-section. Finally, analyze dynamics association/dissociation estimate binding energy tetramer complete versus partially disassembled filament. Our results provide comprehensive description turnover link between fragmentation. SIGNIFICANCE STATEMENT filaments, including vimentin, component cytoskeleton, for Inside cell, fulfill its functions. In particular, elongate fragment, but this breakage was unknown. Here along length, could locally weaken physical understanding mechanisms regulating feature determining dynamic organization both healthy diseased assembly disrupted.

Language: Английский

Citations

2