Bend, Push, Stretch: Remarkable Structure and Mechanics of Single Intermediate Filaments and Meshworks

The cytoskeleton of the eukaryotic cell provides a structural and functional scaffold enabling biochemical and cellular functions. While actin and microtubules form the main framework of the cell, intermediate filament networks provide unique mechanical properties that increase the resilience of both the cytoplasm and the nucleus, thereby maintaining cellular function while under mechanical pressure. Intermediate filaments (IFs) are imperative to a plethora of regulatory and signaling functions in mechanotransduction. Mutations in all types of IF proteins are known to affect the architectural integrity and function of cellular processes, leading to debilitating diseases. The basic building block of all IFs are elongated alpha-helical coiled-coils that assemble hierarchically into complex meshworks. A remarkable mechanical feature of IFs is the capability of coiled-coils to metamorphize into beta-sheets under stress, making them one of the strongest and most resilient mechanical entities in nature. Here, we discuss structural and mechanical aspects of IFs with a focus on nuclear lamins and vimentin.

Automated summary

The eukaryotic cell cytoskeleton is a crucial structural scaffold that supports various biochemical and cellular functions, with the intermediate filament networks playing a key role in providing unique mechanical properties and increasing resilience under mechanical pressure. Mutations in intermediate filaments can lead to architectural integrity and functional issues in cellular processes, highlighting their importance in maintaining cellular function. The remarkable mechanical feature of intermediate filaments lies in their ability to transform under stress, making them one of the strongest and most resilient mechanical entities in nature.