Polarization of pseudopodial activities: cytoskeletal mechanisms.

The reorganization of the cytoskeleton resulting in a stabilized polarization in cells of two types, Dictyostelium amoebae and cultured mammalian fibroblasts, is compared. It is suggested that there are two levels of reorganization: basal level reorganization of actin-myosin cortex and a higher level of reorganization of microtubules and intermediate filaments.