Specialized Mechanisms For Phosphorus Uptake in Plants

Описание: #plants #macronutrients #phosphorus #nutrients #nutrientrich #symbiosis

Phosphorus (P) is a key element in photosynthesis, respiration, and the biosynthesis of nucleic acids and membranes. As a plant macronutrient, P frequently limits productivity in both natural and agricultural systems. In spite of the abundance of phosphate in soil, phosphorus is poorly available to plants. Overuse of phosphorus fertilizers results in low phosphorus use efficiency (PUE).
Plants only take up P as H2PO4− from their rhizosphere, and no organic P. Two important mechanisms for phosphate uptake in higher plant roots are the activity of high affinity phosphate transporters and the symbiotic association with arbuscular mycorrhizal (AM) fungi.
There are four families of phosphorus transporters in Arabidopsis: PHT1, PHT2, PHT3 and PHT4. The PHT1 family comprises high-affinity phosphate/H+ symporters, mostly expressed in the roots with 9 members in Arabidopsis. The transcription of PHT1 transporters is induced by phosphorus starvation. They are responsible for phosphate uptake from the soil and transport to the shoot and the mycorrhizal symbiotic interface. In barley, PHT1.1 and PHT1.2 are expressed in root epidermal, cortical and vascular tissues. PHT1.8 and PHT1.9 are regulated by ubiquitin E2 conjubase PHO2.
WRKY75 is one of several transcription factors induced during inorganic phosphate deprivation. WRKY75 is the first member of the WRKY transcription factor family involved in phosphorus acquisition and root architecture changes.