Different Polycomb group complexes regulate common target genes in Arabidopsis.

ETH Zürich, Institute of Plant Sciences and Zürich-Basel Plant Science Center, Plant Developmental Biology, LFW E 31, Universitätsstrasse 2, Zürich 8092, Switzerland.
EMBO Reports (Impact Factor: 7.19). 10/2006; 7(9):947-52. DOI: 10.1038/sj.embor.7400760
Source: PubMed

ABSTRACT Polycomb group (PcG) proteins convey epigenetic inheritance of repressed transcriptional states. Although the mechanism of the action of PcG is not completely understood, methylation of histone H3 lysine 27 (H3K27) is important in establishing PcG-mediated transcriptional repression. We show that the plant PcG target gene PHERES1 is regulated by histone trimethylation on H3K27 residues mediated by at least two different PcG complexes in plants, containing the SET domain proteins MEDEA or CURLY LEAF/SWINGER. Furthermore, we identify FUSCA3 as a potential PcG target gene and show that FUSCA3 is regulated by MEDEA and CURLY LEAF/SWINGER. We propose that different PcG complexes regulate a common set of target genes during the different stages of plant development.

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