spectrin

A filamentous contractile protein that together with actin and other cytoskeleton proteins forms a network that gives the red blood cell membrane its shape and flexibility; a defect or deficiency of s. is associated with hereditary spherocytosis and hereditary elliptocytosis; the principal component of the membrane skeleton of red cells. It comprises two units, an alpha unit of MW 240,000 [MIM*182860] and a beta unit of MW 225,000 [MIM*182870].

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spec·trin 'spek-trən n a large cytoskeletal protein that is found on the inner cell membrane of red blood cells and that functions esp. in maintaining cell shape

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spec·trin (spekґtrin) a dimeric contractile protein that with ankyrin, actin, glycophorin, and other cytoskeleton proteins forms a fibrous network beneath the plasma membrane of erythrocytes that maintains cell shape and flexibility; defects of spectrin lead to elliptocytosis, spherocytosis, and pyropoikilocytosis.