ERK1/2 has an essential role in B cell receptor- and CD40-induced signaling in an in vitro model of germinal center B cell selection.

•BCR stimulation leads to immediate ERK1/2 activation and phosphorylations of its down-stream targets, Bim and Bcl-2 (Ser70) which results in short-term B cells survival.•BCR-induced late signaling results in apoptosis through inhibition of ERK1/2 activity.•CD40 stimulation leads to immediate and sustained activation of ERK1/2 and up-regulation of Bcl-xL in BCR-primed B cells.