PAG3 (paxillin-associated protein with ADP-ribosylation factor [ARF] GTPase-activating protein GAP] activity, number 3) is a member of the ARF GAP family of proteins that associates with the cytoskeleton, plays an important role in mediating actin cytoskeletal organization in response to adhesion and growth factor stimulation and is involved in paxillin subcellular localization. During monocyte maturation, the elevation of paxillin expression and integrin activation is associated with the induction of PAG3 expression. Overexpression of PAG3 inhibits paxillin recruitment to focal contacts and hinders cellular migration. PAG3 is phosphorylated by Pyk2 kinase on tyrosines 724 and 763.