Tunicamycin can induce the UPRER during both larval stage and early adulthood. (a) Representative images of tunicamycin-induced UPRER in the zcls4[hsp-4p∷GFP] reporter line during the L1 stage. Tunicamycin (5 μg/ml in DMSO) or an equal amount of DMSO (control) is added 24 h before taking images. Scale bar, 100 μm. (b) Quantification of imaging experiments in (a). (c–j) A similar set of experiments are conducted with the zcls4[hsp-4p∷GFP] reporter line at different ages: L4 (c,d), Day 1 adulthood (e,f), Day 4 adulthood (g,h), and Day 9 adulthood (i,j). The UPRER can be induced during larval stages and Day 1 adulthood, but not Day 4 or 9 adulthood. Numbers in parentheses indicate the amount of worms assayed. Data are presented as mean ± SEM, and the statistical significance is assessed using the unpaired student t test. ***p < .001; DMSO, dimethyl sulfoxide; NS, not significant; UPR, unfolded protein response