Inducers of plant systemic acquired resistance regulate NPR1 function through redox changes.

Journal Article (Journal Article)

NPR1 is an essential regulator of plant systemic acquired resistance (SAR), which confers immunity to a broad-spectrum of pathogens. SAR induction results in accumulation of the signal molecule salicylic acid (SA), which induces defense gene expression via activation of NPR1. We found that in an uninduced state, NPR1 is present as an oligomer formed through intermolecular disulfide bonds. Upon SAR induction, a biphasic change in cellular reduction potential occurs, resulting in reduction of NPR1 to a monomeric form. Monomeric NPR1 accumulates in the nucleus and activates gene expression. Inhibition of NPR1 reduction prevents defense gene expression, whereas mutation of Cys82 or Cys216 in NPR1 leads to constitutive monomerization, nuclear localization of the mutant proteins, and defense gene expression. These data provide a missing link between accumulation of SA and activation of NPR1 in the SAR signaling pathway.

Full Text

Duke Authors

Cited Authors

  • Mou, Z; Fan, W; Dong, X

Published Date

  • June 2003

Published In

Volume / Issue

  • 113 / 7

Start / End Page

  • 935 - 944

PubMed ID

  • 12837250

Electronic International Standard Serial Number (EISSN)

  • 1097-4172

International Standard Serial Number (ISSN)

  • 0092-8674

Digital Object Identifier (DOI)

  • 10.1016/s0092-8674(03)00429-x


  • eng