Fig. 5.

Classes of differentially phosphorylated acceptor sites in SLP-65. A, phosphorylation at early and transient acceptor sites occur within the first 2 min upon BCR activation and declines thereafter. B, early and sustained acceptor sites remain phosphorylated even 20 min following BCR activation. C, late acceptor sites undergo phosphorylation upon 20 min of BCR activation. D, down-regulated acceptor sites are phosphorylated already in resting cells and undergo BCR-induced dephosphorylation. Note that phosphorylation of constitutive acceptor sites is unchanged in resting and BCR-activated B cells and is therefore not shown in this figure. Error bars indicate the standard deviations of the obtained fold changes for each phosphorylated residue at each time-point.