FIGURE 10.

Model of MYO3A regulation in actin protrusions. We suggest a model of concentration-dependent regulation by autophosphorylation at the tips of actin protrusions that consists of a multistep process where increased concentration of MYO3A in the tip compartment results in activation of the MYO3A kinase domain by autophosphorylation. Active kinase is then capable of trans-phosphorylation of the motor domain of myosin. Reducing myosin motor activity leads to a loss of MYO3A protein from the tip compartment, thereby regulating the stability of the actin-based structure.