SHC1 (Src homology 2 domain-containing) transforming protein can bind to either phosphorylated tyrosine 1148 (p-Y1148) and/or tyrosine 1173 (p-Y1173) sites on the EGF receptor. The N-terminal phosphotyrosine binding domain (PBD) of SHC1, also known as the phosphotyrosine interaction (PI) domain, binds to phosphorylated p-Y1148 of EGFR, which is part of the NPXpY motif. The SH2 domain of SHC1 binds to p-Y1173 of EGFR (Batzer et al. 1995, Songyang et al. 1995, Sakaguchi et al. 1998).