Figure 5.

ER Stress–Induced Autophagy Is Dependent on IRE1b Function in Arabidopsis Roots.

(A) Seven-day-old wild-type (WT), ire1a, and ire1b plants were transferred to MS liquid medium plus DMSO for 8 h as a control, MS liquid medium supplemented with 5 µg/mL TM or 2 mM DTT for 8 h to induce ER stress, or MS plates lacking Suc (−Suc) or nitrogen (−N) for 4 d to induce starvation stress, followed by MDC staining and confocal microscopy. Bar = 50µm.

(B) The number of MDC-stained autophagosomes per root section was counted after DTT and TM treatment as above and the average number determined for 20 seedlings per treatment. Error bars represent se.