Abstract.
Titins are a family of gigantic filamentous muscle proteins essential for muscle structure, function and development. Most of their sequence consists of repetitive modules of two superfamily motifs, immunoglobulin and fibronectin, interspersed with unique sequences. A special feature is that many regions are differentially expressed in different muscle types, providing unique characteristics. Titin is evolutionarily old, and many regions are highly conserved. Most mutations that alter titin’s characteristics seem to be incompatible with life, since very few associated genetic diseases have been described. The autoimmune response against titin in the paraneoplastic form of myasthenia gravis is discussed.
Keywords: Key words. Titin; titin antibodies; muscle elasticity; sarcomere assembly; myasthenia gravis; thymoma.
Footnotes
Received 4 January 2000; received after revision 20 April 2000; accepted 20 April 2000