Polycomb Repressive Complex 2 Controls the Embryo-to-Seedling Phase Transition
Figure 5
PRC2 represses seed maturation and dormancy genes in the seedling.
All genes provided in this model have been identified as H3K27me3 targets and were significantly up-regulated in fie mutants. They include master regulators of seed development such as AGL15, LEC2, ABI3, FUS3, further downstream regulators such as WRI, integrators of environmental signals such as FLC and finally genes involved in seed storage and desiccation tolerance. * For detailed information which members of the oleosins (oil body coat proteins) and LEAs (late embryogenesis abundant proteins) are affected see Table S5. For LEC2 the up-regulation was only observed in qRT-PCR (Table S4). We find here that the ABA and GA hormonal signaling pathways that play a pivotal role in the transition form seed to seedling are under PRC2 control since genes playing a positive role in ABA signaling as well as genes with a negative role in GA signaling are H3K27me3 marked in wild type and up-regulated in fie. Large letters stand for high and small for low ABA and GA levels, respectively. Abscisic acid (ABA), Gibberellic acid (GA), AGAMOUS-Like 15 (AGL15, AT5G13790), LEAFY COTYLEDON 2 (LEC2, AT1G28300), ABA INSENSITIVE 3 (ABI3, AT3G24650), FUSCA 3 (FUS3, AT3G26790), WRINKLED1 (WRI, AT3G54320), FLOWERING LOCUS C (FLC, AT5G10140), CRUCIFERIN 3 (CRU3, AT4G28520), CRUCIFERINA (CRA1, AT5G44120), SEED STORAGE ALBUMIN 1 (2S1, AT4G27140), SEED STORAGE ALBUMIN 2, (2S2, AT4G27150), HYDROXYSTEROID DEHYDROGENASE 1 (AtHSD1, AT5G50600), Peroxiredoxin 1 (PER1, AT1G48130), ABA INSENSITIVE 4 (ABI4, AT2G40220), DELAY OF GERMINATION 1 (DOG1, AT5G45830), CHOTTO 1/AINTEGUMENTA-LIKE 5 (CHO1/AIL5, AT5G5739), SOMNUS (SOM, AT1G03790), SQUAMOSA PROMOTER BINDING PROTEIN-LIKE 8 (SPL8, AT1G02065), AT-hook protein of GA feedback 1 (AGF1, AT4G35390), GIBBERELLIC ACID METHYLTRANSFERASE 2 (GAMT2, AT5G56300).