Just as other G proteins, Rac acts as a molecular switch, remaining inactive while bound to guanosine diphosphate (GDP) and activated once guanine nucleotide exchange factors (GEFs) remove GDP, permitting guanosine triphosphate (GTP) to bind.
In its activated state, Rac participates in the regulation of cell movement, through its involvement in structural changes to the actin cytoskeleton.
[2] By changing the cytoskeletal dynamics within the cell, Rac-GTPases are able to facilitate the recruitment of neutrophils to the infected tissues, and to regulate degranulation of azurophil and integrin-dependent phagocytosis.
[3] Activated Rac also regulates the effector functions of the target proteins involved in downstream signaling.
As an essential subunit of NOX2 (NADPH oxidase enzyme complex), Rac is required for ROS (reactive oxygen species) production involved in the formation of NETs (neutrophil extracellular traps, thus, facilitating the pathogen and debris clearance by neutrophils, and the reduction of inflammation.