Desmin (Des)

Desmin is a type III intermediate filament found near the Z line in sarcomeres. It was first purified in 1977, the gene was characterized in 1989, and the first knock-out mouse was created in 1996. Desmin is only expressed in vertebrates, however homologous proteins are found in many organisms. It is a 52kD protein that is a subunit of intermediate filaments in skeletal muscle tissue, smooth muscle tissue, and cardiac muscle tissue. The function of desmin has been deduced through studies in knockout mice, however the underlying mechanism of its action is not known. These possibilities may be the result of interactions with other proteins and not desmin itself. More research needs to be done on how desmin's expression and interactions in the muscle cell in order to determine its exact function.