Multiple roles of intermediate filaments.

The widespread distribution, diversity of types, and highly conserved features of intermediate filaments (IFs) and the diversity of associated proteins indicate multiple roles for IFs in the nucleus and the cytoplasm of eukaryotic cells. Traditional functions include maintenance of cell shape, cell locomotion, movement and positioning of organelles and guiding cell development. Recent studies indicate some of these functions can now be expanded. Currently available information shows that IFs are important to nuclear function and cell division, to transport between the nucleus and cytoplasm, to the mechanical integrity of cells and tissues, to reorganization of the cytoplasm and chromatin in response to intercellular signals, and to embryonic and cellular differentiation.