Emerging functions: diseases and animal models reshape our view of the cytoskeleton.

Intermediate filaments (IFs), desmosomes, and their associates are built from multidomain proteins that form cytoskeletal scaffolds in the cytoplasm and the nucleus of vertebrate tissues. Mutations in more than 80 genes cause monogenic disorders that include severe skin fragility, myopathies, neurodegeneration, and premature ageing, and contribute to polygenic disorders including liver and inflammatory bowel disease. First interpreted as "mechanical weakness" disorders resulting from a weakened cytoskeleton, emerging data support the concept that changes in cytoskeletal architecture profoundly alter signal transduction and cellular transcription patterns. This is in line with cell type-specific interactions between cytoskeletal and their associated proteins, and may involve both soluble and insoluble forms of intermediate filament proteins. Understanding how mutation-induced disruption of the cytoskeleton and its upstream regulators causes disease at the molecular level presents one of the major challenges in future research.