Spectrins

Spectrins are a family of cytoskeletal proteins found in the red blood cells of vertebrates. They play a crucial role in maintaining the shape and flexibility of these cells, which is essential for their ability to transport oxygen efficiently. Spectrins are composed of two types of subunits: alpha and beta. The alpha subunits are anchored to the membrane skeleton, while the beta subunits form a flexible rod-like structure that connects the alpha subunits to each other. This structure allows the red blood cells to deform and flow through narrow capillaries, a process known as erythrocyte deformation. Spectrins are also involved in the regulation of red blood cell volume and shape, as well as in the maintenance of the membrane skeleton. Mutations in spectrin genes have been linked to various hemolytic anemias, including hereditary spherocytosis and hereditary elliptocytosis. Spectrins are named for their ability to bind to the membrane skeleton protein ankyrin, which is also involved in the regulation of red blood cell shape and volume. The spectrin family includes several members, such as spectrin alpha-1, spectrin alpha-2, spectrin beta-1, and spectrin beta-2, each with distinct functions and tissue distributions.