Figure 4
From: EBNA3C interacts with Gadd34 and counteracts the unfolded protein response
A: EBNA3C effects on phosphorylation the translational control protein eIF2α. LCL 19-9 was maintained in the presence (+HT) or absence (-HT) of hydroxytamoxifen for 10 days. Shown are western blots from whole-cell lysates against EBNA3C (top row), serine 51 phosphorylated eIF2α (second row), total eIF2α (third row) and β-actin loading control (fourth row). By day 10, in the absence of HT, LCL19-9 cells had stopped dividing [7]. B: EBNA3C protects LCLs from activating the unfolded protein response. As in Figure 4a except that cells were also treated with either DMSO "C" or 0.5 μM Thapsigargin "Tg", for the 4 hrs preceding harvest. XBP1(s) and XBP1(u) were individually detected using isoform specific antibodies. An ATF6 antibody that detects only full length, uncleaved ATF6 (90 KDa) was used (Imgenex, San Diego, CA).