FIGURE 2.

Phosphopeptide mapping of the GST-LRP1-CT. GST-LRP1-CT fusion proteins were incubated with [γ-³²P]ATP and full-length v-Src followed by SDS-PAGE and autoradiography. Phosphorylated LRP1 was excised from the gel and digested with trypsin, and the resulting peptide mixture was resolved in two dimensions by electrophoresis and chromatography. A, wild type GST-LRP1-CT, yielded two major ³²P-phospho-peptides. B, Y4507E GST-LRP1-CT yielded one ³²P-phospho-peptide. C, Y4473F GST-LRP1-CT yielded one ³²P-phospho-peptide. D, schematic map of the ³²P-phosphopeptides derived from the tryptic digest of phospho-GST-LRP1-CT.