A) CD19+ B splenocytes from wt and chop-/- mice were cultured in vitro with 20 μg/ml LPS for the indicated time points. chop mRNA expression pattern during differentiation was followed by relative real time PCR as in Fig.1 C.
B) Nuclear accumulation of CHOP protein in B splenocytes, differentiated as in panel A, was followed by Western blot analyses. When indicated, cells were treated with 2 μg/ml thapsigargin (Th) for 3 hrs. Ponceau staining of a region of the nitrocellulose filter is shown as loading control.
C) CHOP is transiently induced also in in vivo differentiating B cells. c57/BL6 mice were injected intra-peritoneally with LPS. After LPS injection, 3 mice were sacrificed at each time point and differentiating B cells were purified and mixed to extract total RNA. CHOP transcript was detected as in panel A.