| First Author | Blasioli J | Year | 1999 |
| Journal | J Biol Chem | Volume | 274 |
| Issue | 4 | Pages | 2303-7 |
| PubMed ID | 9890995 | Mgi Jnum | J:200343 |
| Mgi Id | MGI:5508302 | Doi | 10.1074/jbc.274.4.2303 |
| Citation | Blasioli J, et al. (1999) Definition of the sites of interaction between the protein tyrosine phosphatase SHP-1 and CD22. J Biol Chem 274(4):2303-7 |
| abstractText | CD22 phosphorylation is an early event of B cell antigen receptor engagement and results in the recruitment of the negative regulatory tyrosine phosphatase, SHP-1. Peptides representing the potential phosphorylation sites within the cytoplasmic domain of CD22 have been used to stimulate SHP-1 catalytic activity and to inhibit the binding of SHP-1 to CD22 (Doody, G., Justement, L., Delibrias, C., Matthews, R., Lin, J., Thomas, M., and Fearon, D. (1995) Science 269, 242-244). However, the sites of phosphorylation within the cytoplasmic domain of CD22 and the importance of each for the recruitment and activation of SHP-1 remain unknown. Here we demonstrate that there are multiple sites within the cytoplasmic domain of CD22 that interact with the Src homology 2 domains of SHP-1. Nevertheless, a minimum of two tyrosines in CD22 is required for the association with SHP-1. Furthermore, both Src homology 2 domains of SHP-1 are necessary for efficient binding to CD22. |
