Brassinosteroid, gibberellin and phytochrome impinge on a common transcription module in Arabidopsis.

Published

Journal Article

Brassinosteroid and gibberellin promote many similar developmental responses in plants; however, their relationship remains unclear. Here we show that BR and GA act interdependently through a direct interaction between the BR-activated BZR1 and GA-inactivated DELLA transcription regulators. GA promotion of cell elongation required BR signalling, whereas BR or active BZR1 suppressed the GA-deficient dwarf phenotype. DELLAs directly interacted with BZR1 and inhibited BZR1-DNA binding both in vitro and in vivo. Genome-wide analysis defined a BZR1-dependent GA-regulated transcriptome, which is enriched with light-regulated genes and genes involved in cell wall synthesis and photosynthesis/chloroplast function. GA promotion of hypocotyl elongation requires both BZR1 and the phytochrome-interacting factors (PIFs), as well as their common downstream targets encoding the PRE-family helix-loop-helix factors. The results demonstrate that GA releases DELLA-mediated inhibition of BZR1, and that the DELLA-BZR1-PIF4 interaction defines a core transcription module that mediates coordinated growth regulation by GA, BR and light signals.

Full Text

Duke Authors

Cited Authors

  • Bai, M-Y; Shang, J-X; Oh, E; Fan, M; Bai, Y; Zentella, R; Sun, T-P; Wang, Z-Y

Published Date

  • August 2012

Published In

Volume / Issue

  • 14 / 8

Start / End Page

  • 810 - 817

PubMed ID

  • 22820377

Pubmed Central ID

  • 22820377

Electronic International Standard Serial Number (EISSN)

  • 1476-4679

International Standard Serial Number (ISSN)

  • 1465-7392

Digital Object Identifier (DOI)

  • 10.1038/ncb2546

Language

  • eng