Polyphosphoinositides as regulators of membrane skeletal stability.

The membrane skeleton is a two-dimensional complex of actin, spectrinlike, and associated proteins which lies on the cytoplasmic face of most plasma membranes. Components of this complex are believed to control the lateral mobility of integral membrane proteins as well as influence cell shape and motility. In earlier studies we observed that the addition of polyphosphorylated inositol lipids could increased membrane skeleton dissociation. In preliminary studies of leukocyte function we have observed that increased chemotaxis with Trental addition is correlated with increased polyphosphoinositide levels. Consequently, we suggest that polyphosphoinositides contribute to, if not are requisite for, cellular mobility.