CDC42 promotes changes in actin cytoskeleton by several pathways.
CDC42 activates PAK1,2,3,4 and CDC42BPA (MRCKalpha) which phosphorylate LIMK1,2.
LIMK1,2 subsquently phosphorylate and inhibit Cofilin
Destrin as actin depolymerizing factor, once phosphorylated by LIMK1,2 is inactive and thus this phosphorylation leads to actin polymerization and stimulation of filopodia and stress fibers formation.
LIMK1 is regulated by Pak1,