Sweet memories: epigenetic control in flowering

Many plants respond to winter with epigenetic factors that gradually dampen repression of flowering so that they can flower in spring. The study of this process was important for the identification of the plant Polycomb group (PcG) of proteins and their role in the epigenetic control of plant gene expression. Fittingly, these studies continue to illuminate our understanding of PcG function. We discuss recent advances, particularly the role of noncoding RNA in the recruitment of PcG to target genes, and the role of the PcG in regulating the stem cell pool in flowers.