Phosphorylation regulation of nitrogen, phosphorus, and potassium uptake systems in plants

The uptake of ammonium, nitrate, phosphorus, and potassium ions by roots is mediated by specific ion transporter or channel proteins, and protein phosphorylation regulation events occurring on these proteins and their regulators determine their ultimate activity. Elucidating the mechanism by which protein phosphorylation modification regulates nutrient uptake will advance plant breeding for high nutrientuse efficiency. In this review, it is concluded that the root nutrient absorption system is composed of several, but not all, members of a specific ion transporter or channel family. Under nutrient-starvation conditions, protein phosphorylation-based regulation of these proteins and associated transcription factors increases ion transporter-or channel-mediated nutrient uptake capacity via direct function activity enhancement, allowing more protein trafficking to the plasma membrane, by strengthening the interaction of transporters and channels with partner proteins, by increasing their protein stability, and by transcriptional activation. Under excessive nutrient conditions, protein phosphorylation-based regulation suppresses nutrient uptake by reversing these processes. Strengthening phosphorylation regulation items that increase nutrient absorption and weakening phosphorylation modification items that are not conducive to nutrient absorption show potential as strategies for increasing nutrient use efficiency.