Cortactin (CTTN)

Cortactin is a monomeric protein located in the cytoplasm of cells that can be activated by external stimuli to promote polymerization and rearrangement of the actin cytoskeleton, especially the actin cortex around the cellular periphery. It is present in all cell types. When activated, it will recruit Arp2/3 complex proteins to existing actin microfilaments, facilitating and stabilizing nucleation sites for actin branching. Cortactin is important in promoting lamellipodia formation, invadopodia formation, cell migration, and endocytosis.Cortactin is a thin, elongated monomer that consists of an amino-terminal acidic (NTA) region; 37-residue-long segments that are highly conserved among cortactin proteins of all species and which are repeated up to 6.5 times in tandem (“cortactin repeats”); a proline-rich region; and an SH3 domain.