Bundles of stiff filaments are ubiquitous in the living world, found both in the cytoskeleton and in the extracellular medium. These bundles are typically held together by smaller cross-linking molecules. We demonstrate, analytically, numerically, and experimentally, that such bundles can be kinked, that is, have localized regions of high curvature that are long-lived metastable states. We propose three possible mechanisms of kink stabilization: a difference in trapped length of the filament segments between two cross-links, a dislocation where the endpoint of a filament occurs within the bundle, and the braiding of the filaments in the bundle. At a high concentration of cross-links, the last two effects lead to the topologically protected kinked states. Finally, we explore, numerically and analytically, the transition of the metastable kinked state to the stable straight bundle.

Data is divided into Experimental results and Simulation results. 

For "Experiment-images.zip": Images reconsituted collagen were taken using Olympus Fluoview 1200 system with 60x oil 1.45 NA objective. 

For "Simulation results": Data has been split into 31 zip files. Once unzipped files are divided into /input/ and /output/.

Further detail can be found in attached readme files ("readme_simulation_data.txt" and "ExperimentREADME.txt") and in the full publication, https://doi.org/10.1073/pnas.2024362118.

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