Nitrogen Actively Controls the Phosphate Starvation Response in Plants

Li Yan 22:48:31 05/12/2020

Nitrogen (N) and phosphorus (P) are key macronutrients sustaining plant growth and crop yield, and

ensuring food security worldwide. Understanding how plants perceive and interpret the combinatorial

nature of these signals thus has important agricultural implications within the context of: i) increased food

demand, ii) limited P supply, and iii) environmental pollution due to N fertilizer usage. Here we report the

discovery of an active control of P Starvation Responses (PSR) by a combination of local and long-distance

N signaling pathways in plants. We show that, in Arabidopsis thaliana, the nitrate transceptor CHLORINA 1/

NITRATE TRANSPORTER 1.1 (CHL1/NRT1.1) is a component of this signaling crosstalk. We also

demonstrate that this crosstalk is dependent on the control of the accumulation and turnover by N of the

transcription factor PHOSPHATE STARVATION RESPONSE 1/PHR1, a master regulator of P sensing and

signaling. We further show an important role of PHOSPHATE 2/PHO2 as an integrator of the N availability

into the PSR since the effect of N on PSR is strongly affected in pho2 mutants. We finally show that PHO2

and NRT1.1 influence each other’s transcript levels. These observations are summarized in a model

representing a framework with several entry points where N signal influence PSR. Finally, we demonstrate

that this phenomenon is conserved in rice (Oryza sativa) and wheat (Triticum aestivum) opening

biotechnological perspectives in crop plants.

Recommended Series