Nitrate Sensing and Signaling in Plants: Comparative Insights and Nutritional Interactions

Plant nitrogen nutrition is an essential and energy-costly component of terrestrial food chains. Understanding nitrate sensing in plants can lead to improved crop yields and nutrient use efficiency, directly impacting food security and agricultural sustainability. Herein, we review and present a comprehensive framework for understanding nitrate sensing in plants, integrating molecular, genetic, and physiological aspects. We begin by detailing the primary nitrate response and nitrate starvation response, which are central to the plant’s ability to sense and respond to nitrate availability. We then explore the intricate interactions between nitrate signaling and other nutritional pathways such as those for carbon, phosphorus, potassium, and sulfur assimilation and reactive oxygen species (ROS) handling, and how it unfolds in long-distance systemic communication between roots and shoots.