Fig. 1. LS174T cells expressing XBP1(s) or ATF6^1–373 upregulate general UPR target genes.

a Quantitative RT-PCR analysis for XBP1(s) and downstream target genes upon induction of XBP1(s) expression. b Protein level of XBP1(s) and GRP78 in LS174T XBP1(s)^{Tet On} cells. Cells were incubated for 0, 1 or 3 h with thapsigargin 200 nM. Note that transgenic XBP1(s) had a slightly lower molecular weight than endogenous XBP1(s). c Immunostaining of XBP1 in LS174T XBP1(s)^{Tet On} cells. d Quantitative RT-PCR analysis for ATF6^1–373 and downstream target genes upon induction of ATF6^1–373 expression. e Protein level of GRP78 in LS174T ATF6^{1–373 Tet On} cells. Cells were treated with vehicle or doxycycline 1 μg/mL for 18 h. All data are shown as means ± SEM. *P < 0.05, **P < 0.01, ***P < 0.001