Figure 2.

Stages assigned to Arabidopsis embryo development and an overview of PSV formation in a representative cell from selected stages. A, Images of heart, torpedo, walking stick, and bent cotyledon embryos dissected from Arabidopsis ovules. The mature embryo was dissected from a dry seed. Bar = 100 µm. B, PSV arise during the maturation phase of embryonic development. Images shows single micrographs from SBF-SEM stacks of embryos at different developmental stages. Deposits of electron-opaque material (arrows) are first observed in the vacuole lumen and along the tonoplast of the EV in early-bent cotyledon embryos. The deposits accumulate and eventually fill the vacuolar lumen in mature seed. Asterisks indicate oil bodies. Bar at left for high-magnification images = 1 µm; bar at right for inset overview images = 100 µm.