Figure 2
ZAP-70 protein overexpression enhances the induction of miR-21 expression after BCR stimulation in B cells via MAPK and STAT3 activation. (a–b) Ramos stable transfectants were stimulated with 5 µg/mL F(ab’)2 anti-IgM for 4 and 12 hours. Expression levels of primary miR-21 (a) and miR-21 (b) were measured by QRT-PCR. (c–d) Ramos GFP-ZAP-70 cells were stimulated with 5 µg/mL F(ab’)2 anti-IgM for 5 minutes after pre-incubation for 1 hour with 5 µM or 10 µM LY294002 for Akt inhibition or 50 µM or 100 µM PD98059 for ERK1/2 inhibition. Immunobloting analysis confirmed the inhibition of phosphorylation of Akt and ERK1/2 (Jurkat cells treated with PV were used as positive control) (c) and expression levels of miR-21 were measured by QRT-PCR after 12 hours (d). (e–f) Ramos stable transfectants were stimulated with 5 µg/mL F(ab’)2 anti-IgM for 5 minutes and pre-treated 1 hour with 5 µM JSI-124 for STAT3 inhibition. Immunobloting analysis confirmed the inhibition of STAT3 phosphorylation (Jurkat cells treated with PV were used as positive control) (e) and expression levels of miR-21 were measured by QRT-PCR after 48 hours (f). *P < 0.05, **P < 0.005.
