Dating 50 plus Gribskov
Therefore, in this study we defined the developmental phase of the endosperm based on the stages of the embedded embryos.
Under our growth conditions, the globular-shape embryo stage is reached approximately six days after flowering (DAF), the heart-shape embryo stage is reached after eight days, and by day 14 the seed enters the cotyledon stage (Figure ).
Then, using a glass pipette with a fine tip, the endosperm was extracted and collected into pools based on whether embryo development was at the globular-shape, heart-shape or cotyledon stages (Figure ).
In mature seeds, the endosperm is depleted to a single aleuronic layer in the mature seeds.
This illustrates the dramatic cellular and biochemical shifts the endosperm undergoes during seed development.
Because the number of ESTs was not sufficient to justify separation into different pools, we combined the data into one endosperm database.
For protein profile analysis, we focused only on endosperm in ovules containing heart-shape embryos because they exhibit all phases of endosperm development [.