Figure 7.

Defects in Autophagy Induction in ire1b during ER Stress Can Be Attributed to the Loss of IRE1b Gene Function.

(A) Leaf protoplasts obtained from 4-week-old wild-type (WT) or ire1b plants were transformed with the GFP-ATG8e fusion construct, or ire1b leaf protoplasts were transformed with both GFP-ATG8e and IRE1b-FLAG fusion constructs. For controls, the protoplasts were incubated in W5 solution. To induce ER stress, protoplasts were incubated in W5 solution plus 5 µg/mL TM. Arrows indicate GFP-ATG8e–labeled autophagic bodies.

(B) Seven-day-old wild-type, ire1b, and ire1b/IRE1b-FLAG seedlings were transferred to MS liquid medium supplemented with 5 µg/mL TM or DMSO as a solvent control for 8 h, followed by MDC staining and fluorescence microscopy. Arrows indicate MDC-stained autophagosomes and autophagic bodies.