The Arabidopsis SWI/SNF protein BAF60 mediates seedling growth control by modulating DNA accessibility

Genome Biol. 2017 Jun 15;18(1):114. doi: 10.1186/s13059-017-1246-7.


Background: Plant adaptive responses to changing environments involve complex molecular interplays between intrinsic and external signals. Whilst much is known on the signaling components mediating diurnal, light, and temperature controls on plant development, their influence on chromatin-based transcriptional controls remains poorly explored.

Results: In this study we show that a SWI/SNF chromatin remodeler subunit, BAF60, represses seedling growth by modulating DNA accessibility of hypocotyl cell size regulatory genes. BAF60 binds nucleosome-free regions of multiple G box-containing genes, opposing in cis the promoting effect of the photomorphogenic and thermomorphogenic regulator Phytochrome Interacting Factor 4 (PIF4) on hypocotyl elongation. Furthermore, BAF60 expression level is regulated in response to light and daily rhythms.

Conclusions: These results unveil a short path between a chromatin remodeler and a signaling component to fine-tune plant morphogenesis in response to environmental conditions.

Keywords: Chromatin; DNA accessibility; G-box; Morphogenesis; PIF4; Phytochrome Interacting Factor; SWI/SNF.

MeSH terms

  • Arabidopsis / genetics
  • Arabidopsis / growth & development
  • Arabidopsis Proteins / genetics*
  • Basic Helix-Loop-Helix Transcription Factors / genetics*
  • Chromatin Assembly and Disassembly
  • Chromosomal Proteins, Non-Histone / genetics*
  • DNA, Plant / genetics
  • DNA-Binding Proteins / genetics*
  • Gene Expression Regulation, Plant
  • Hypocotyl / genetics
  • Hypocotyl / growth & development*
  • Nucleosomes / genetics
  • Seedlings / genetics*
  • Seedlings / growth & development
  • Transcription Factors / genetics*


  • Arabidopsis Proteins
  • BAF60 protein, Arabidopsis
  • Basic Helix-Loop-Helix Transcription Factors
  • Chromosomal Proteins, Non-Histone
  • DNA, Plant
  • DNA-Binding Proteins
  • Nucleosomes
  • PIF4 protein, Arabidopsis
  • SWI-SNF-B chromatin-remodeling complex
  • Transcription Factors