| First Author | Hippen KL | Year | 1997 |
| Journal | Immunity | Volume | 7 |
| Issue | 1 | Pages | 49-58 |
| PubMed ID | 9252119 | Mgi Jnum | J:42001 |
| Mgi Id | MGI:894921 | Doi | 10.1016/s1074-7613(00)80509-9 |
| Citation | Hippen KL, et al. (1997) Fc gammaRIIB1 inhibition of BCR-mediated phosphoinositide hydrolysis and Ca2+ mobilization is integrated by CD19 dephosphorylation. Immunity 7(1):49-58 |
| abstractText | The B cell receptor for immunoglobulin G, Fc gammaRIIB1, is a potent transducer of signals that block antigen-induced B cell activation. Coligation of Fc gammaRIIB1 with B lymphocyte antigen receptors (BCR) causes premature termination of phosphoinositide hydrolysis and Ca2+ mobilization and inhibits proliferation. This inhibitory signal is mediated in part by phosphorylation of Fc gammaRIIB1 and recruitment of phosphatases; however, the molecular target(s) of effectors is unknown. Here we report that Fc gammaRIIB1 inhibition of BCR signaling is mediated in part by selective dephosphorylation of CD19, a BCR accessory molecule and coreceptor. CD19 dephosphorylation leads to failed CD19 association with phosphatidylinositol 3-kinase, and this in turn leads to termination of inositol-1,4,5-trisphosphate production, intracellular Ca2+ release, and Ca2+ influx. The results define a molecular circuit by which Fc gammaRIIB signals block phosphoinositide hydrolysis. |
