The SNL-HDA19 histone deacetylase complex antagonizes HY5 activity to repress photomorphogenesis in Arabidopsis

作  者:Jing YJ*, Guo Q, Lin RC*
刊物名称:New Phytologist
卷:  期:  页码:DOI: 10.1111/nph.17114


  • Reprogramming of the transcriptome during photomorphogenesis requires dynamic changes in chromatin and distribution of histone modifications. However, the chromatinbased regulation of this process remains to be elucidated.
  • Here, we identify the conserved SWIINDEPENDENT3 LIKE (SNL)HISTONE DEACETYLASE19 (HDA19) deacetylase complex, including HDA19 and SNL1–SNL6, as a negative regulator of the light signaling pathway. Lightrepression of HDA19 and SNLs expression is mediated by photoreceptors. HDA19 and SNLs are required for histone deacetylation and chromatin inactivation of PHYA gene. We further examined the interaction between SNLHDA19 complex and ELONGATED HYPOCOTYL5 (HY5), and their antagonistic regulation on the expressions of target genes.
  • The HDA19 deacetylase complex is recruited by HY5 to the chromatin regions of two positive light signaling genes, HY5 and BBOX CONTAINING PROTEIN 22 (BBX22), thereby reduces the accessibility and histone acetylation and represses their expression. HDA19, SNL1, and HY5 associate with the same regulatory regions of HY5 and BBX22, and HY5 binding to these loci is enhanced upon SNLHDA19 dysfunction.
  • Our study reveals a crucial role for the HDA19 deacetylase complex in light signaling and demonstrates that the functional interplay between chromatin regulators and transcription factors regulates photomorphogenetic responses to the changing light environments.