Ras homolog gene family, member A (RhoA) downstream effector Rho-associated, coiled-coil containing protein kinase (ROCK) directly phosphorylates LIM domain kinases 1 and 2 (LIMK1 and LIMK2) that in turn phosphorylates Cofilin. Cofilin exhibits Actin-depolymerizing activity followed by reorganization of the Actin cytoskeleton [1].

The activated ROCK also subsequently phosphorylates and inactivates the Myosin light chain phosphatase (MLCP) [2] that attenuates Myosin light chains (MELC) (myosin light chains) and Myosin light chain regulatory (MRLC) phosphorylation [3].

Ras-related C3 botulinum toxin substrate 1 (Rac1) downstream effector P21 protein-activated kinase 1 (PAK1) directly phosphorylates LIMK1 [4], inhibits MLCK [5], activates MRLC [6] and ARP2 actin-related protein 2 and 3 (Arp2/3) complex [7]. Arp2/3 complex nucleates new Actin filaments from the sides of preexisting filaments. [8]. Also, WAS protein family member 1 (WAVE) plays a critical role downstream of Rac in that it regulates the Actin cytoskeleton required for membrane ruffling. WAVE share function as an inducer of Actin reorganization through profiling [9].

Cell division cycle 42 (CDC42) initiates Wiskott-Aldrich syndrome (WASP)/Arp2/3 nucleation of Actin [10]. Recruitment of factors, including Profilin, by WASP stimulates cellular Actin-based motility [11].

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