Abstract
Plant endoplasmic reticulum (ER) is a unique organelle originating various compartments such as COP II vesicles, precursor accumulating (PAC) vesicles, ER-bodies, and protein bodies (PB-ER), in association with the developmental stages of plants or under the external stimuli. However, the molecular mechanism underlying the development of their organelles from the ER is not known. To demonstrate the heterogeneity and various ability of ER, we focused on one of ER-derived compartments, PB-ER, in which prolamin, a rice storage protein, aggregates to prolamin protein body. In this study, prolamin fused to green fluorescent protein (prolamin-GFP) was expressed in Arabidopsis plant and tobacco BY2 suspension cultured cells. The GFP fluorescent images were compared with those of the transformed Arabidopsis plants expressing ER-targeted GFP/RFP (SP-GFP/RFP-HDEL). Our results suggest the differentiation of the ER lumen.
