Proteasome-mediated turnover of the transcription coactivator NPR1 plays dual roles in regulating plant immunity.

Published

Journal Article

Systemic acquired resistance (SAR) is a broad-spectrum plant immune response involving profound transcriptional changes that are regulated by the coactivator NPR1. Nuclear translocation of NPR1 is a critical regulatory step, but how the protein is regulated in the nucleus is unknown. Here, we show that turnover of nuclear NPR1 protein plays an important role in modulating transcription of its target genes. In the absence of pathogen challenge, NPR1 is continuously cleared from the nucleus by the proteasome, which restricts its coactivator activity to prevent untimely activation of SAR. Surprisingly, inducers of SAR promote NPR1 phosphorylation at residues Ser11/Ser15, and then facilitate its recruitment to a Cullin3-based ubiquitin ligase. Turnover of phosphorylated NPR1 is required for full induction of target genes and establishment of SAR. These in vivo data demonstrate dual roles for coactivator turnover in both preventing and stimulating gene transcription to regulate plant immunity.

Full Text

Duke Authors

Cited Authors

  • Spoel, SH; Mou, Z; Tada, Y; Spivey, NW; Genschik, P; Dong, X

Published Date

  • May 2009

Published In

Volume / Issue

  • 137 / 5

Start / End Page

  • 860 - 872

PubMed ID

  • 19490895

Pubmed Central ID

  • 19490895

Electronic International Standard Serial Number (EISSN)

  • 1097-4172

International Standard Serial Number (ISSN)

  • 0092-8674

Digital Object Identifier (DOI)

  • 10.1016/j.cell.2009.03.038

Language

  • eng