Fig. 7

ER Stress Response Affects M-Cell Axon Regeneration. a Timeline of time points of 4-PBA treatment, axotomy, and regeneration imaging. b, c Representative confocal imaging of Mauthner-cell axon in wfs1b^+/+ treated with DMSO, wfs1b^+/+ treated with 4-PBA, wfs1b^−/− treated with DMSO, and wfs1b^−/− treated with 4-PBA at 8 dpf and the regeneration length at 2 dpa (wfs1b^+/+  + DMSO: 431.7 ± 14.12 μm, n = 28; wfs1b^+/+  + 4-PBA:432.7 ± 21.63 μm, n = 15; wfs1b^−/− + DMSO: 274.2 ± 25.80 μm, n = 20; wfs1b^−/− + 4-PBA: 432.0 ± 29.26 μm, n = 15). Assessed by two-way ANOVA/Tukey’s multiple-comparisons test (wfs1b^+/+  + DMSO versus wfs1b^+/+  + 4-PBA: P > 0.9999; wfs1b^+/+  + DMSO versus wfs1b^−/− + DMSO: P < 0.0001; wfs1b^−/− + DMSO versus wfs1b^−/− + 4-PBA: P < 0.0001; wfs1b^+/+  + 4-PBA versus wfs1b^−/− + DMSO: P < 0.0001). Scale bar, 20 μm. ns, not significant. d–f qPCR analyses of downstream genes of the UPR pathway. Assessed by ordinary one-way ANOVA. g Timeline of time points of TM treatment, axotomy, and regeneration imaging. h, i Representative confocal imaging of Mauthner-cell axon in wfs1b^+/+ treated with DMSO, wfs1b^+/+ treated with TM, wfs1b^−/− treated with DMSO, and wfs1b^−/− treated with TM at 8 dpf and the regeneration length at 2 dpa (wfs1b^+/+  + DMSO: 456.9 ± 19.27 μm, n = 21; wfs1b^+/+  + TM: 323.4 ± 15.80 μm, n = 23; wfs1b^−/− + DMSO: 266.1 ± 21.94 μm, n = 13; wfs1b^−/− + TM: 263.2 ± 17.29 μm, n = 16). Assessed by two-way ANOVA/Tukey’s multiple-comparisons test (wfs1b^+/+  + DMSO versus wfs1b^+/+  + TM: P < 0.0001; wfs1b^+/+  + DMSO versus wfs1b^−/− + DMSO: P < 0.0001; wfs1b^+/+  + DMSO versus wfs1b^−/− + TM: P < 0.0001; wfs1b^−/− + DMSO versus wfs1b^−/− + TM: P = 0.9997). Scale bar, 20 μm. ns, not significant. j–l qPCR analyses of downstream genes of the UPR pathway. Assessed by unpaired t test. White asterisk: ablation point