The genetics of the protein 4.1 family: organizers of the membrane and cytoskeleton

Protein 4.1 (also called band 4.1 or simply 4.1) was originally identified as an abundant protein of the human erythrocyte, in which it stabilizes the spectrin/actin cytoskeleton. The protein and its relatives have since been found in many cell types of metazoan organisms and they are often concentr ated in the nucleus, as well as in cell-cell junctions. They form multimole cular complexes with transmembrane and membrane-associated proteins, and th ese complexes may be important for both structural stability and signal tra nsduction at sites of cell contact.