Identification of autophosphorylation sites of HER2/neu.

摘要: HER2 or c-erbB-2 is a putative growth factor receptor with sequence homology to the epidermal receptor. It human homologue of rat protooncogene neu and may have an important role in malignancies such as breast ovarian cancers. Like other receptors, has intrinsic protein tyrosine kinase activity undergoes autophosphorylation. Recently, we demonstrated that, similar receptor, all autophosphorylation sites are localized carboxyl terminus this protein. In present study, immunopurified was allowed autophosphorylate, tryptic phosphopeptides were generated. After purification these by high performance liquid chromatography, microsequencing performed. Utilizing approach, two unequivocally identified at Y1023 Y1248. The sequences phosphorylated peptides determined, but exact site could not be determined because multiple tyrosines located on each peptide. However, contains that correspond major suggesting addition Y1248, Y1139 Y1222 also serve HER2.