| Here , we search for other binding partners for the IRSp 53 SH3 domain and identify Eps 8 as the major binding protein in fibroblasts and various cancer cell lines . ^^^ We confirm the IRSp53 / Eps8 complex formation in vivo and the direct association between Eps 8 NH ( 2 ) terminal proline rich sequence and IRSp 53 SH3 domain . ^^^ |