Fig. 7. Interaction between IRSp53, Mena and WAVE2. Mena is recruited to the protruding tips of both lamellipodia and filopodia through the synergetic function of its EVH1 and EVH2 domains. WAVE2 is recruited to the tips through the WHD domain. IRSp53 binding to the proline-rich region of WAVE2 enhances the activity of WAVE2 to stimulate the Arp2/3 complex. Because IRSp53 also binds to the proline-rich region of Mena, IRSp53 may tie WAVE2 and Mena into a complex. The shaded boxes show the proline-rich regions. Double-ended solid arrows between molecules indicate the previously reported interactions. Grey arrows show the tethering activity to the tips of both lamellipodia and filopodia. Arp2/3, Arp2/3 complex; B, basic region; CRIB, Cdc42 and Rac interactive binding motif; EVH, Ena/VASP homology; fil/ms, filopodium/microspike; lam, lamellipodium; RCB, Rac binding region; SH, Src homology domain; VCA, Verprolin-Cofilin homology and acidic domain; WHD, WAVE/Scar homology domain.