Figure 5. Effects of TBL2 knockdown on the PERK pathway.

(A) 293 cells were transiently transfected with non-silencing siRNA, two TBL2 siRNAs (#1, #2) or PERK siRNAs (#1, #2). After 48 h, the cells were treated with 300 nM thapsigargin for 90 min and analyzed by immunoblot anaysis. (B) 293 cells were transiently transfected with non-silencing siRNA, two TBL2 siRNAs (#1, #2) or PERK siRNAs (#1, #2). The protein synthesis rate was measured by incorporating [³⁵S]methionine/cysteine. The pulse labeling was carried out during the last 20 min of the 40-min thapsigargin (Tg) treatment (100 or 300 nM). Upper: autoradiography image of SDS-PAGE. Lower panel: TCA precipitation sample was measured using a scintillation counter.