Forced CIN85 expression inhibits BCR-induced calcium flux and phosphorylation of Syk and PLCγ2. (A-B) Control BJAB cells and stable transformants expressing either WT or SH3-deleted CIN85 were stimulated with 20 μg/mL of F(ab′)2 goat anti–human IgM for the indicated time periods. The cell lysates were subsequently separated on a 10% SDS-PAGE gel and analyzed by Western blotting with anti–phospho-Syk pAb, anti-Syk mAb, anti–phospho-PLCγ2 pAb, anti-PLCγ2 pAb, anti–phospho-Akt pAb, or anti-Akt pAb. The resulting values are expressed as fold changes in protein expression compared with unstimulated control cells. The values are the mean ± SD of 3 independent experiments (*P < .05, **P < .01 vs controls). (C) Ca2+ influx in control BJAB cells and stable transformants expressing either WT or SH3-deleted CIN85. The intracellular free calcium levels in Fluo 4/AM-loaded cells were analyzed using flow cytometry after the cells were stimulated with 20 μg/mL F(ab′)2 goat anti–human IgM. The results shown are representative of 4 independent experiments.
