Genomic organization of the Shc-related phosphotyrosine adapters and characterization of the full-length Sck/ShcB: Specific association of p68-Sck/ShcB with pp135

The She gene family is an emerging family, containing at least three members designated Shc/ShcA, Sck/Sli/ShcB, N-Shc/Rai/ShcC in mammals. In this study, we determined the genomic organization of the mouse She family. Coding regions of ShcA, B, and C each comprised 12 exons, spanned approximately 6, 20, and 65 kb, and located on chromosome 3, 10, and 13, respectively. Based on this genome analysis, we determined the full-length structure of mouse Sck/ShcB as a 68-kD protein. We found that the 68-kD full-length Sck/ShcB was more efficiently phosphorylated upon EGF treatment than the previously-analyzed CH2-deleted form. We also found that Sck specifically interacted with a 135-kD phosphoprotein (pp135) through its SH2 domain following membrane depolarization. The Sck-pp135 interaction was reduced by Src kinase inhibitors. These results suggest that Sck, but not N-Shc nor She, transmit signals in conjunction with pp135 following Src activation and/or calcium entry in the cell. (C) 2001 Academic Press.