In response to VEGF, the increased actin polymerization required to trigger actin based motility involves the recruitment of adapter protein NCK to VEGFR2 (Lamalice et al. 2007). Phosphorylated tyrosine 1214 in VEGFR2 is the binding site for NCK. NCK later recruits FYN and PAK2, which are required for the activation of SAPK2/p38 activation, formation of stress fibers, and endothelial cell migration (Lamalice et al. 2006, Stoletov et al. 2004, Lu et al. 1997). NCK also participates in a signaling pathway leading to actin nucleation and polymerization through its interactions with N WASP and WAVE1 (Stoletov et al. 2004, Rhoatgi et al. 2001).