A B-ARR-mediated cytokinin transcriptional network directs hormone cross-regulation and shoot development

Nat Commun. 2018 Apr 23;9(1):1604. doi: 10.1038/s41467-018-03921-6.

Abstract

Cytokinin fulfills its diverse roles in planta through a series of transcriptional responses. We identify the in vivo DNA binding site profiles for three genetically redundant type-B ARABIDOPSIS RESPONSE REGULATORS (B-ARRs): ARR1, ARR10, and ARR12. The expression and genome-wide DNA binding locations of the three B-ARRs extensively overlap. Constructing a primary cytokinin response transcriptional network reveals a recurring theme of widespread cross-regulation between the components of the cytokinin pathway and other plant hormone pathways. The B-ARRs are found to have similar DNA binding motifs, though sequences flanking the core motif were degenerate. Cytokinin treatments amalgamate the three different B-ARRs motifs to identical DNA binding signatures (AGATHY, H(a/t/c), Y(t/c)) which suggests cytokinin may regulate binding activity of B-ARR family members. Furthermore, we find that WUSCHEL, a key gene required for apical meristem maintenance, is a cytokinin-dependent B-ARR target gene, demonstrating the importance of the cytokinin transcription factor network in shoot development.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Arabidopsis / physiology*
  • Arabidopsis Proteins / genetics*
  • Arabidopsis Proteins / metabolism
  • Binding Sites
  • Cytokinins / genetics
  • Cytokinins / metabolism*
  • DNA / metabolism
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism
  • Gene Expression Regulation, Plant / physiology*
  • Gene Regulatory Networks / physiology
  • Homeodomain Proteins / genetics*
  • Meristem / physiology
  • Nucleotide Motifs / physiology
  • Plant Growth Regulators / genetics*
  • Plants, Genetically Modified
  • Protein Binding / physiology
  • Transcription Factors / genetics
  • Transcription Factors / metabolism

Substances

  • ARR1 protein, Arabidopsis
  • ARR10 protein, Arabidopsis
  • ARR12 protein, Arabidopsis
  • Arabidopsis Proteins
  • Cytokinins
  • DNA-Binding Proteins
  • Homeodomain Proteins
  • Plant Growth Regulators
  • Transcription Factors
  • WUSCHEL protein, Arabidopsis
  • DNA