Hierarchical Structure Controls Nanomechanical Properties of Vimentin Intermediate Filaments

Intermediate filaments (often abbreviated as IFs), in addition to microtubules and microfilaments, are one of the three major components of the cytoskeleton in eukaryotic cells (Figure 1). It has been suggested that intermediate filaments are crucial in defining key mechanical functions of cells such as cell migration, cell division and mechanotransduction, and have also been referred to as the “safety belts of cells” reflecting their role in preventing exceedingly large cell stretch [1, 2]. Vimentin is a specific type of this protein filament found in fibroblasts, leukocytes, and blood vessel endothelial cells, representing the most widely distributed type of intermediate filaments. Several diseases have been linked to the structure and density of intermediate filaments. Here we report a systematic study of the effects of intermediate filaments on cell mechanics, specifically focused on changes in the density of filaments. We compare the results with experimental studies in vimentin deficient cells, showing good qualitative agreement.