AtNIGT1/HRS1 integrates nitrate and phosphate signals at the Arabidopsis root tip

Nat Commun. 2015 Feb 27;6:6274. doi: 10.1038/ncomms7274.


Nitrogen and phosphorus are among the most widely used fertilizers worldwide. Nitrate (NO3(-)) and phosphate (PO4(3-)) are also signalling molecules whose respective transduction pathways are being intensively studied. However, plants are continuously challenged with combined nutritional deficiencies, yet very little is known about how these signalling pathways are integrated. Here we report the identification of a highly NO3(-)-inducible NRT1.1-controlled GARP transcription factor, HRS1, document its genome-wide transcriptional targets, and validate its cis-regulatory elements. We demonstrate that this transcription factor and a close homologue repress the primary root growth in response to P deficiency conditions, but only when NO3(-) is present. This system defines a molecular logic gate integrating P and N signals. We propose that NO3(-) and P signalling converge via double transcriptional and post-transcriptional control of the same protein, HRS1.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Arabidopsis / growth & development*
  • Arabidopsis / metabolism
  • Arabidopsis Proteins / metabolism*
  • Computational Biology
  • DNA Primers / genetics
  • Electrophoretic Mobility Shift Assay
  • Gene Expression Profiling
  • Immunoblotting
  • Likelihood Functions
  • Meristem / metabolism*
  • Microscopy, Fluorescence
  • Models, Genetic
  • Nitrates / metabolism*
  • Phosphates / metabolism*
  • Phylogeny
  • Real-Time Polymerase Chain Reaction
  • Signal Transduction / physiology*
  • Transcription Factors / metabolism*


  • Arabidopsis Proteins
  • DNA Primers
  • HRS1 protein, Arabidopsis
  • Nitrates
  • Phosphates
  • Transcription Factors

Associated data

  • GEO/GSE64352