Involved in high-affinity nitrate transport (PubMed:15107992). Required for the nitrate uptake-independent plant growth promotion and lateral root response to the rhizospheric Phyllobacterium (PubMed:23398541). Expressed in roots and shoots (PubMed:12668777). Expressed in leaves (PubMed:23398541). Not induced by nitrate or by growth on low nitrate concentration (PubMed:12668777, PubMed:15107992). Strongly up-regulated upon inoculation with the plant growth-promoting rhizobacteria Phyllobacterium (PubMed:16160849). Loss of plant growth and root system architecture responses to the rhizospheric Phyllobacterium. Belongs to the major facilitator superfamily. Nitrate/nitrite porter (TC 2.A.1.8) family.