Interaction of the Arabidopsis UV-B-specific signaling component UVR8 with chromatin

Mol Plant. 2008 Jan;1(1):118-28. doi: 10.1093/mp/ssm012. Epub 2007 Oct 31.

Abstract

Arabidopsis UV RESISTANCE LOCUS8 (UVR8) is a UV-B-specific signaling component that regulates expression of a range of genes concerned with UV protection. Here, we investigate the interaction of UVR8 with chromatin. Using antibodies specific to UVR8 in chromatin immunoprecipitation (ChIP) assays with wild-type plants, we show that native UVR8 binds to chromatin in vivo. Similar experiments using an anti-GFP antibody with plants expressing a GFP-UVR8 fusion show that UVR8 associates with a relatively small region of chromatin containing the HY5 gene. UVR8 interacts with chromatin containing the promoter regions of other genes, but not with all the genes it regulates. UV-B is not required for the interaction of UVR8 with chromatin because association with several gene loci is observed in the absence of UV-B. Pull-down assays demonstrate that UVR8 associates with histones in vivo and competition experiments indicate that the interaction is preferentially with histone H2B. ChIP experiments using antibodies that recognize specific histone modifications indicate that the UV-B-stimulated transcription of some genes may be correlated with histone modification. In particular, the ELIP1 promoter showed a significant enrichment of diacetyl histone H3 (K9/K14) following UV-B exposure. These findings increase understanding of the interaction of the key UV-B-specific regulator UVR8 with chromatin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / physiology*
  • Arabidopsis Proteins / radiation effects
  • Blotting, Western
  • Chromatin / physiology*
  • Chromatin / radiation effects
  • Chromosomal Proteins, Non-Histone / genetics
  • Chromosomal Proteins, Non-Histone / physiology*
  • Chromosomal Proteins, Non-Histone / radiation effects
  • Gene Expression Regulation, Plant / radiation effects
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / radiation effects
  • Histones / metabolism
  • Histones / radiation effects
  • Polymerase Chain Reaction
  • Promoter Regions, Genetic / radiation effects
  • Recombinant Fusion Proteins / radiation effects
  • Signal Transduction / physiology
  • Signal Transduction / radiation effects
  • Transcription, Genetic* / radiation effects
  • Ultraviolet Rays*

Substances

  • Arabidopsis Proteins
  • Chromatin
  • Chromosomal Proteins, Non-Histone
  • Histones
  • Recombinant Fusion Proteins
  • Uvr8 protein, Arabidopsis
  • Green Fluorescent Proteins