Tyrosine residues 239 and 240 of Shc are phosphatidylinositol 4,5-bisphosphate-dependent phosphorylation sites by c-Src.
In the previous study (Sato K.-I. et al. (1997) FEBS Lett. 410, 136-140), we showed that the phosphorylation of Shc protein by c-Src is dependent on the binding of phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2) to the PTB domain of Shc. In this study, we demonstrate that, in contrast to c-Src, v-Src and epidermal growth factor (EGF) receptor can phosphorylate Shc in a PtdIns(4,5)P2-independent manner and at different phosphorylation sites. To determine the phosphorylation sites in Shc, we used mutant Shc proteins in which tyrosine residues (Y) 317 and/or 239 and 240 were replaced by phenylalanine residues (F). We found that Y317F Shc but not Y239/240F or Y239/240/317F Shc was phosphorylated by c-Src. The reaction was PtdIns(4,5)P2-dependent and inhibited by the addition of PTB domain of Shc. On the other hand, v-Src and EGF receptor were able to phosphorylate both Y317F and Y239/240F but not Y239/240/317F Shc in a PtdIns(4,5)P2-independent manner. These results highlight the difference between c-Src and v-Src or EGF receptor and suggest that c-Src can phosphorylate predominantly on Tyr239/240 of Shc only when Shc PTB domain is bound to PtdIns(4,5)P2.
Sato
K
K
Laboratory of Molecular Biology, Kobe University, Japan. ksato@inherit.biosig.kobe-u.ac.jp
Gotoh
N
N
Otsuki
T
T
Kakumoto
M
M
Aoto
M
M
Tokmakov
A A
AA
Shibuya
M
M
Fukami
Y
Y
D048868:Adaptor Proteins, Signal Transducing; D033942:Adaptor Proteins, Vesicular Transport; D019943:Amino Acid Substitution; D000818:Animals; D001921:Brain / Q000378:metabolism; D002294:Carcinoma, Squamous Cell; D002417:Cattle; D002461:Cell Line, Transformed; D066246:ErbB Receptors / Q000378:metabolism; D005982:Glutathione Transferase; D006801:Humans; D051379:Mice; D016297:Mutagenesis, Site-Directed; D015688:Oncogene Protein pp60(v-src) / Q000378:metabolism; D019269:Phosphatidylinositol 4,5-Diphosphate / Q000378:metabolism* / Q000494:pharmacology*; D011494:Protein Kinases / Q000378:metabolism; D011506:Proteins / Q000737:chemistry* / Q000378:metabolism*; D016392:Proto-Oncogene Proteins pp60(c-src) / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000378:metabolism; D055765:Shc Signaling Adaptor Proteins; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1; D014407:Tumor Cells, Cultured; D014443:Tyrosine
D048868:Adaptor Proteins, Signal Transducing; D033942:Adaptor Proteins, Vesicular Transport; D019269:Phosphatidylinositol 4,5-Diphosphate; D011506:Proteins; D011993:Recombinant Fusion Proteins; C528024:SHC1 protein, human; D055765:Shc Signaling Adaptor Proteins; C528034:Shc1 protein, mouse; D000071425:Src Homology 2 Domain-Containing, Transforming Protein 1; D014443:Tyrosine; D005982:Glutathione Transferase; D011494:Protein Kinases; D066246:ErbB Receptors; D015688:Oncogene Protein pp60(v-src); D016392:Proto-Oncogene Proteins pp60(c-src)