Figure 4.

Carbohydrate transport to and metabolism within the chalazal region of the seed. A, A seed at the single-cell stage of the embryo proper is shown to illustrate the two chalazal regions (chalazal seed coat in red and chalazal endosperm in blue) used in transcriptome analyses. B to E, Expression values (log₂ scale) for starch synthesis (B), starch degradation (C), GPT1 (D), and highly expressed invertase and monosaccharide transporters (E) during early embryo development. For a full expression analysis of the 197 genes in these and other tissues, see Supplemental Figures S2 and S3; for the full names of the genes, see Table I.