DMP1-eGFP fluorescence patterns during development in A. thaliana. In mature/early senescing rosette leaves DMP1-eGFP expressed from the native DMP1 promoter localizes in the ER (a) and occasionally in ER bodies (b). Vesiculation of the ER in rosette leaves during late NS (c). Vesiculation of the vacuole in rosette leaves during late NS (d, e). Vesiculation of the ER and the vacuole in rosette leaves during late NS (f1-f5). F1-F5 are individual pictures of a Z-stack through vesiculated ER (f1 and f2) and the central vacuole undergoing fragmentation (f2-f5, arrows). The integrity of the nuclear envelope is retained at this stage (f5, empty arrowhead). Bolus formation in cauline leaves during late NS (g). Bolus formation in silique walls during late NS (h). Bolus formation in rosette leaves of darkened whole plants (i). Vesiculation of the ER in rosette leaves during DIS (j). The polygonal architecture of the ER is still visible despite strong bolus formation and punctate distribution of fluorescence signals (g-i) or vesiculation (j). DMP1-eGFP is strongly expressed in the cortex of root tips (k-o), in phloem bundles (p), and weakly expressed in other cell layers of the root (q). In the cortex DMP1-eGFP localizes to the tonoplast, highlighting vacuole biogenesis (k, single picture, m maximal projection and i, light transmission). Magnification of the region near the root tip (n) shows multiple vacuoles of different size and shape which tend to form a central vacuole in the root elongation zone (o). Subcellular localization in the phloem bundle could not been determined but strong fluorescence signals in structures which might be ER boluses were observed (p). ER localization in roots is shown in (q, arrow). Scale bar, 10 μm.