Figure 7: Proposed model: NO3− and P limitation signals are integrated by the control of HRS1 at the transcriptional and post-transcriptional level, respectively.
From: AtNIGT1/HRS1 integrates nitrate and phosphate signals at the Arabidopsis root tip
On NO3− treatment, the NRT1.1 and NLP7 regulatory module induces rapid HRS1 transcript and protein accumulation. The prolonged P deficiency condition negatively affects the accumulation of HRS1 and modifies its regulatory activity. Furthermore, the P limitation signal seems to control the NO3− sensor (NRT1.1) protein half-life. This delineates a working model to understand several points of NO3− and PO43− signal interactions via the HRS1 pathway.
