Physical clustering of FLC alleles during Polycomb-mediated epigenetic silencing in vernalization

Genes Dev. 2013 Sep 1;27(17):1845-50. doi: 10.1101/gad.221713.113.


Vernalization, the promotion of flowering by cold, involves Polycomb-mediated epigenetic silencing of FLOWERING LOCUS C (FLC). Cold progressively promotes cell-autonomous switching to a silenced state. Here, we used live-cell imaging of FLC-lacO to monitor changes in nuclear organization during vernalization. FLC-lacO alleles physically cluster during the cold and generally remain so after plants are returned to warm. Clustering is dependent on the Polycomb trans-factors necessary for establishment of the FLC silenced state but not on LIKE HETEROCHROMATIN PROTEIN 1, which functions to maintain silencing. These data support the view that physical clustering may be a common feature of Polycomb-mediated epigenetic switching mechanisms.

Keywords: FLC; Polycomb; epigenetic; nuclear organization; vernalization.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles
  • Arabidopsis / genetics*
  • Arabidopsis / metabolism
  • Arabidopsis Proteins / genetics*
  • Carrier Proteins / genetics
  • Chromosomal Proteins, Non-Histone / genetics
  • Cold Temperature
  • DNA-Binding Proteins
  • Epigenesis, Genetic / genetics*
  • Gene Expression Regulation, Plant*
  • Gene Silencing / physiology*
  • MADS Domain Proteins / genetics*
  • Multigene Family / genetics*
  • Nuclear Proteins / genetics
  • Plant Roots / metabolism
  • Polycomb-Group Proteins / metabolism*
  • Transgenes


  • Arabidopsis Proteins
  • Carrier Proteins
  • Chromosomal Proteins, Non-Histone
  • DNA-Binding Proteins
  • FLF protein, Arabidopsis
  • MADS Domain Proteins
  • Nuclear Proteins
  • Polycomb-Group Proteins
  • VRN2 protein, Arabidopsis
  • VRN5 protein, Arabidopsis
  • like heterochromatin protein 1