O-GlcNAcylation of master growth repressor DELLA by SECRET AGENT modulates multiple signaling pathways in Arabidopsis.

Journal Article

The DELLA family of transcription regulators functions as master growth repressors in plants by inhibiting phytohormone gibberellin (GA) signaling in response to developmental and environmental cues. DELLAs also play a central role in mediating cross-talk between GA and other signaling pathways via antagonistic direct interactions with key transcription factors. However, how these crucial protein-protein interactions can be dynamically regulated during plant development remains unclear. Here, we show that DELLAs are modified by the O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT) SECRET AGENT (SEC) in Arabidopsis. O-GlcNAcylation of the DELLA protein REPRESSOR OF ga1-3 (RGA) inhibits RGA binding to four of its interactors-PHYTOCHROME-INTERACTING FACTOR3 (PIF3), PIF4, JASMONATE-ZIM DOMAIN1, and BRASSINAZOLE-RESISTANT1 (BZR1)-that are key regulators in light, jasmonate, and brassinosteroid signaling pathways, respectively. Consistent with this, the sec-null mutant displayed reduced responses to GA and brassinosteroid and showed decreased expression of several common target genes of DELLAs, BZR1, and PIFs. Our results reveal a direct role of OGT in repressing DELLA activity and indicate that O-GlcNAcylation of DELLAs provides a fine-tuning mechanism in coordinating multiple signaling activities during plant development.

Full Text

Duke Authors

Cited Authors

  • Zentella, R; Hu, J; Hsieh, W-P; Matsumoto, PA; Dawdy, A; Barnhill, B; Oldenhof, H; Hartweck, LM; Maitra, S; Thomas, SG; Cockrell, S; Boyce, M; Shabanowitz, J; Hunt, DF; Olszewski, NE; Sun, T-P

Published Date

  • January 2016

Published In

Volume / Issue

  • 30 / 2

Start / End Page

  • 164 - 176

PubMed ID

  • 26773002

Electronic International Standard Serial Number (EISSN)

  • 1549-5477

International Standard Serial Number (ISSN)

  • 0890-9369

Digital Object Identifier (DOI)

  • 10.1101/gad.270587.115

Language

  • eng