Fig. 6.

Schematic representations of the dynamics of chromatin compaction, nuclear size, and moisture content during the transition from embryo to seedling. Arabidopsis embryonic cotyledon nuclei significantly decrease in size during seed maturation and increase again during germination (Fig. 1). Chromatin compaction increases throughout seed maturation, resulting in a high level of compaction in dry seeds (Figs. 2 and 3). In the first 3 d after imbibition, the chromatin decondensates dramatically, followed by a rapid increase in compaction during early seedling establishment and vegetative growth. Note that the dynamics of chromatin compaction and nuclear size are independent processes that occur largely independent of changes in moisture content. The dynamics of moisture content during seed maturation is based on Baud et al. (4), and that during imbibition is based on Preston et al. (20). Chromatin compaction during seedling establishment is based on Mathieu et al. (16). The y-axes represent relative scales.