THE SH3 DOMAIN OF EPS8 EXISTS AS A NOVEL INTERTWINED DIMER

SH3 domains are structurally well-characterized as monomeric modular u nits of protein structure that mediate protein-protein recognition in numerous signal transduction proteins, The X-ray crystallographic stru cture of the Eps8 SH3 domain reveals a novel variation of the canonica l SH3 fold: the SH3 domain from Eps8 is a dimer formed by strand inter change, In addition, co-immunoprecipitation experiments show that inta ct Eps8 is multimeric in vivo. Hence, the SH3 domain of Eps8 may repre sent a dimerization motif,