A gene loop containing the floral repressor FLC is disrupted in the early phase of vernalization. (7th December 2012)

• Record Type: Journal Article
• Authors: Crevillén, Pedro; Sonmez, Cagla; Wu, Zhe; Dean, Caroline
• Is Part Of: EMBO journal. Volume 32:Number 1(2013)
• Page Start: 140
• Page End: 148
• Publication Date: 2012-12-07
• Subjects: chromosome conformation capture -- FLC -- gene loop -- Polycomb -- vernalization; Molecular biology -- Periodicals; 572.805
• DOI: 10.1038/emboj.2012.324
• Languages: English
• ISSNs: 0261-4189

Abstract

Abstract : Gene activation in eukaryotes frequently involves interactions between chromosomal regions. We have investigated whether higher‐order chromatin structures are involved in the regulation of the Arabidopsis floral repressor gene FLC, a target of several chromatin regulatory pathways. Here, we identify a gene loop involving the physical interaction of the 5′ and 3′ flanking regions of the FLC locus using chromosome conformation capture. The FLC loop is unaffected by mutations disrupting conserved chromatin regulatory pathways leading to very different expression states. However, the loop is disrupted during vernalization, the cold‐induced, Polycomb‐dependent epigenetic silencing of FLC . Loop disruption parallels timing of the cold‐induced FLC transcriptional shut‐down and upregulation of FLC antisense transcripts, but does not need a cold‐induced PHD protein required for the epigenetic silencing. We suggest that gene loop disruption is an early step in the switch from an expressed to a Polycomb‐silenced state. A gene loop containing the floral repressor FLC is disrupted in the early phase of vernalization: Arabidopsis flowering requires a cold spell (vernalization) involving downregulation of the FLC flowing repressor, which is linked to a gene loop between the 5′ and 3′ regions of the FLC locus. Loop formation is disrupted during cold exposure coinciding with downregulation of FLC expression and accumulation of antisense transcripts.