Figure 4.

Cab45S increases the GRP78/BiP protein level. (a and d) Western blots of GRP78/BiP and two other ER molecular chaperones, PDI and calnexin, in stable Cab45S-knockdown (a) or Cab45S-overexpressed (d) PANC-1 cell lines. Numbers represent different cell lines. (b and c) Western blots (b) and quantification (c) of GRP78/BiP in Cab45S-knockdown and control (shNC, scrambled shRNA) HeLa cells treated with TM (2 μg/ml) for the indicated periods. GAPDH was used as a loading control. (e) Quantitative real-time PCR of the relative GRP78/BiP mRNA expression levels in Cab45S-knockdown and control HeLa cells treated with TM for the indicated times (n=3). (f) Western blots of GRP78/BiP in Cab45S-knockdown and control HeLa cells treated with TM (2 μg/ml, 4 h) followed by cycloheximide (Chx; 100 μM) for the indicated periods. For c and e, data are presented as mean±S.E.M. **P<0.01, ***P<0.001, as determined by unpaired two-tailed Student's t-test