Expression patterns of GUS reporter constructs during Arabidopsis embryo development. Promoter:GUS transcriptional fusion constructs were generated with 10 selected embryo-expressed genes: At4g17800 (A); At1g67320 (B); At5g20885 (C); At5g43250 (D); At5g66070 (E); At1g27470 (F); At2g27250 (G); At5g41880 (H); At5g37478 (I); and At5g63780 (J). The expression values of these genes are shown in Supplemental Table S8c. These 10 reporter constructs were introduced into Arabidopsis and the corresponding transgenic lines were analyzed for GUS expression during embryo development. A range of expression patterns were observed including broad expression in the embryo (B, H–J), expression in the basal region (A), predominant expression in the apical region of the embryo and suspensor (D), expression in the axis and provascular domain (C and F), and expression in the shoot apical meristem (E and G) that includes CLAVATA3 (At2g27250)-based GUS reporter with a consistent expression pattern as previously reported (G). Overall, these GUS reporter expression patterns are consistent with the corresponding microarray results.