Figure 4.

Rac1 and RhoA in efferocytic receptor signaling. Engagement of efferocytic receptors induces the initial recruitment of active (GTP-bound) RhoA to the membrane (left), which produces an initial inhibitory signal. Sufficient efferocytic receptor signaling induces the GTPase activity of RhoA, returning it to the inactive (GDP-bound) state, enabling efferocytic synapse formation (middle). The combined signaling of efferocytic receptors and integrins converges on DOCK180, which induces the activation of Rac1. Rac1 then mediates actin polymerization, which extends the efferocyte membrane around the apoptotic cell (right).