A protein involved in the initiation of actin polymerization
The formation of cellular projections like lamellipodia and ruffles is accompanied by de novo actin nucleation and polymerization of actin filaments. Several protein factors like the Arp 2/3 complex
, WASP/Scar and small GTPases of the Rho family have been shown to participate in this process.
The Arp 2/3 complex is activated by GTP-loaded Rac 1 via WAVE proteins. The S
c-associated protein or Sra 1
, also referred to as cytoplasmic FMR 1 interacting protein 1, has been shown to interact with WAVE 2 and other proteins like Abi 1 at the tips of membrane protrusions.