// NATURE NEWS — SPAZIO & SCIENZA
Mechanisms of Transcriptional Regulation by Salicylic Acid Receptors
Nature
(2026) Cite this article
We’re sharing this article early to provide faster access to peer-reviewed, accepted research. It is citable and carries a permanent DOI. This version is subject to further edits and will be replaced automatically by the final Version of Record. All legal disclaimers apply.
Salicylic acid (SA) is a key phytohormone that activates plant defense responses 1-3. In Arabidopsis, NPR1 (also known as NIM1) and NPR3/NPR4 have been identified as dual SA receptors responsible for perceiving SA 4-6. However, the mechanisms of how SA binding to the NPR proteins leads to induction of defense gene expression remain unclear. Here, we elucidate how SA triggers transcriptional activation via NPR1 and relieves transcriptional repression mediated by NPR3/NPR4. We identified Mediator Complex Subunit 15A (MED15A) as a bridge between NPR1 and the Mediator complex governing transcription. SA induces direct interaction of NPR1 with MED15A. Structural and functional analysis showed that the binding of NPR1 to MED15A is essential for NPR1-mediated transcriptional activation. Meanwhile, SA relieves transcriptional repression mediated by NPR3/NPR4. NIM1-interacting 1 (NIMIN1) interacts with NPR3/NPR4 and the Topless (TPL) co-repressor, connecting them to Polycomb Repressive Complex 2 (PRC2) to mediate H3K27 trimethylation of SA-responsive genes. SA inhibits the interactions between NPR3/NPR4 and NIMIN1, reduces H3K27 trimethylation levels and increases histone acetylation of the target genes to release NPR3/NPR4-mediated repression. Our study offers a comprehensive view of SA-mediated defense gene activation. These findings lay a foundation for designing more effective SA analogs as agrochemicals and for engineering crop resistance by manipulating SA perception and signaling.
This is a preview of subscription content, access via your institution
Access Nature and 54 other Nature Portfolio journals
Get Nature+, our best-value online-access subscription
Prices may be subject to local taxes which are calculated during checkout
These authors contributed equally: Yujun Peng, Hainan Tian
Key Laboratory of Bio-resource and Eco-environment of Ministry of Education, State Key Laboratory of Hydraulics and Mountain River Engineering, Key Laboratory for Ex Situ Conservation and Resource Utilization of Mountain Plants of Sichuan Province, Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province, College of Life Sciences, Sichuan University, Chengdu, China
Yujun Peng, Hainan Tian, Jiuyang Yu, Mingsong Wu, Danyi Huang, Yihan Zhang, Zhenhui Zhong & Yuelin Zhang