A histone deacetylase complex establishes a transgenerationally inherited maternal epigenetic state controlling progeny seed dormancy

Mother plants play an important role in the control of dormancy and dispersal characters of their progeny. In Arabidopsis seed dormancy is imposed by the embryo-surrounding tissues of the endosperm and seed coat. Here we show that the VERNALIZATION5/VIN3-LIKE 3 (VEL3) gene maintains maternal control over progeny seed dormancy by establishing an epigenetic state early in endosperm development that primes the depth of primary seed dormancy later established during seed maturation. VEL3 relocates MSI1 to the nucleolus and associates with other components of the histone deacetylase complex (HDAC), and is required for gene repression via PRC2 and HDAC at pericentromeric regions established in the central cell. Interestingly, the epigenetic state established by the maternal VEL3 is retained trans-generationally in mature seeds, and controls seed dormancy through the repression of programmed cell death-associated gene ORE1. Our data demonstrates a novel mechanism by which maternal control of progeny seed physiology persists post-shedding, maintaining parental control of seed behaviour.