Intermediate Filaments

Intermediate filaments (7-11 nm in diameter) provide mechanical strength and resistance to shear stress. They are composed of intermediate filament proteins, which constitute a big and heterogeneous family, that form rope-like fibers. In higher animals skin  contains  an extensive  network  of intermediate  filaments made up of the protein keratin that has a two-stranded  α-helical coiled- coil  structure,  whilst  the  nuclear  lamina,  a  meshwork  just  beneath  the  inner nuclear membrane, is formed from another type of intermediate filament.