Spectrin, together with actin and a number of other accessory proteins
, forms a submembrane cytoskeletal network in the human erythrocyte gh
ost. Through an elegant combination of structural, biochemical, and ge
netic studies, spectrin was shown to be an important determinant of er
ythrocyte shape and membrane stability. Genetic studies of a novel non
erythroid spectrin (PH) in Drosophila and Caenorhabditis elegans now r
eveal that spectrin can influence the shape and stability of whole org
anisms.((1,2)) Nonerythroid spectrins are proposed to have roles in ce
ll adhesion, establishment of cell polarity, and attachment of other c
ytoskeletal structures to the plasma membrane. The phenotypes of the P
H spectrin mutations provide an exciting biological context in which t
o evaluate these roles and perhaps to uncover new ones. (C) 1998 John
Wiley & Sons, Inc.