Arpin

Regulates actin polymerization by inhibiting the actin- nucleating activity of the Arp2/3 complex; the purpose is competetive with nucleation promoting factors. Participates in an incoherent feedforward loop at the lamellipodium point where it inhibits the ARP2/2 complicated in response to Rac signaling and where Rac also stimulates actin polymerization through the WAVE complex.

Involved in steering cell migration by controlling its directional persistence (By similarity). .