FIG. 1.

EGFR constructs employed in this study. Each construct was tagged at its C terminus with YFP. EGFR(Y1045F) contains a single phenylalanine substitution at tyrosine 1045 which has been shown to abolish its ability to interact directly with c-Cbl (27). EGFR1044, an EGFR truncated after residue 1044, should conceivably lack both direct c-Cbl interaction (via pY1045) and indirect interaction at pY1068 and pY1086 via Grb2. The EGFR-LL/AA mutant, in which alanines replace two critical leucines at positions 1010 and 1011, has been previously reported to be deficient in ligand-induced internalization (52). EGFR991, EGFR973, and EGFR957 are EGFRs truncated from their C termini to positions 991, 973, and 957, respectively, and were constructed previously (52). TM, transmembrane domain; JM, juxtamembrane domain; PLCy1, phospholipase C-γ1; pTyr, phosphotyrosine.