The Arabidopsis thaliana Vernalization Response Requires a Polycomb-Like Protein Complex That Also Includes Vernalization Insensitive 3

• Published in: Proceedings of the National Academy of Sciences - PNAS 2006-09, Vol.103 (39), p.14631-14636
• Main Authors: Wood, Craig C., Robertson, Masumi, Tanner, Greg, Peacock, W. James, Dennis, Elizabeth S., Helliwell, Chris A.
• Format: Article
• Language: English
• Subjects: Amino Acid Sequence; Antibodies; Arabidopsis - physiology; Arabidopsis Proteins - genetics; Arabidopsis Proteins - metabolism; Arabidopsis thaliana; Biological Sciences; Carrier Proteins - genetics; Chromatin; Chromatography, Gel; Cold Temperature; DNA-Binding Proteins - genetics; DNA-Binding Proteins - metabolism; Epigenetics; Epitopes; Flowering; Flowers & plants; Gene Expression Regulation, Plant; Genetic Complementation Test; Histones; Homeodomain Proteins - genetics; MADS Domain Proteins - metabolism; Messenger RNA; Molecular Sequence Data; Molecular Weight; Multiprotein Complexes - metabolism; Mutation - genetics; Nuclear Proteins - genetics; Phenotype; Plants; Polycomb-Group Proteins; Proteins; Recombinant Fusion Proteins - chemistry; Recombinant Fusion Proteins - metabolism; Repression; Repressor Proteins - genetics; Repressor Proteins - metabolism; RNA, Messenger - genetics; RNA, Messenger - metabolism; Temperature; Transcription Factors - genetics; Transcription Factors - metabolism; Vernalization
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.0606385103

In Arabidopsis thaliana, the promotion of flowering by cold temperatures, vernalization, is regulated via a floral-repressive MADS box transcription factor, FLOWERING LOCUS C (FLC). Vernalization leads to the epigenetic repression of FLC expression, a process that requires the polycomb group (PcG) protein VERNALIZATION 2 (VRN2) and the plant homeodomain protein VERNALIZATION INSENSITIVE 3 (VIN3). We demonstrate that the repression of FLC by vernalization requires homologues of other Polycomb Repressive Complex 2 proteins and VRN2. We show in planta that VRN2 and VIN3 are part of a large protein complex that can include the PcG proteins FERTILIZATION INDEPENDENT ENDOSPERM, CURLY LEAF, and SWINGER. These findings suggest a single protein complex is responsible for histone deacetylation at FLC and histone methylation at FLC in vernalized plants. The abundance of the complex increases during vernalization and declines after plants are returned to higher temperatures, consistent with the complex having a role in establishing FLC repression.