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Krug, T.

Publications and source records attributed to Krug, T..

2 recordsLinked to original sources

FilaBuster: A Strategy for Rapid, Specific, and Spatiotemporally Controlled Intermediate Filament Disassembly

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

cell biology↗

Phase separated liquid vimentin droplets stabilize actin fibers through wetting

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

biophysics↗