When lipid diacylglycerol (DAG) binds to the C1 domain, CHN1 is transferred to the plasma membrane and negatively regulates Rho-family small GTPases RAC1 and CDC42, thus causing the morphological change of axons by pruning the ends of axon dendrites.
The actin cytoskeleton directly determines the morphology of the spine, and actin regulators, small GTPases such as Rac, RhoA, and CDC42, rapidly modify this cytoskeleton.
mTORC2 has been shown to function as an important regulator of the cytoskeleton through its stimulation of F-actin stress fibers, paxillin, RhoA, Rac1, Cdc42, and protein kinase C α (PKCα).
RhoU/Wrch delineates with RhoV/Chp a Rho subclass related to Rac and Cdc42, which emerged in early multicellular organisms during evolution.
It also inhibits cdc42 by binding to its tail and preventing its insertion into membranes; hence it cannot trigger WASPs and cannot lead to nucleation of F-actin.