InterPro domain: IPR044772

This entry represents a group of nitrate transporters that belong to the Major Facilitator Superfamily (MFS) of membrane transport proteins. Proteins in this entry include high-affinity nitrate transporters NRT2 from plants, and nitrate/nitrite transporters NarK2/NarT/NasA/NarU from bacteria [ 1 , 2 , 3 , 4 ].

NRT2 family proteins are involved in the uptake of nitrate by plant roots from the soil through the high-affinity transport system (HATS). There are seven Arabidopsis thaliana NRT2 proteins, called AtNRT2:1 to AtNRT2:7 [ 5 , 6 ]. This entry also includes fungal nitrate transporters such as CRNA from Emericella nidulans [ 7 ].

1. The nasB operon and nasA gene are required for nitrate/nitrite assimilation in Bacillus subtilis. J. Bacteriol. 177, 1409-13
2. Role of narK2X and narGHJI in hypoxic upregulation of nitrate reduction by Mycobacterium tuberculosis. J Bacteriol 185, 7247-56
3. A single channel for nitrate uptake, nitrite export and nitrite uptake by Escherichia coli NarU and a role for NirC in nitrite export and uptake. Biochem. J. 417, 297-304
4. The Paracoccus denitrificans NarK-like nitrate and nitrite transporters-probing nitrate uptake and nitrate/nitrite exchange mechanisms. Mol Microbiol 103, 117-133
5. The Arabidopsis nitrate transporter NRT2.5 plays a role in nitrate acquisition and remobilization in nitrogen-starved plants. Plant J 80, 230-41
6. A 150 kDa plasma membrane complex of AtNRT2.5 and AtNAR2.1 is the major contributor to constitutive high-affinity nitrate influx in Arabidopsis thaliana. Plant Cell Environ 38, 1490-502
7. crnA encodes a nitrate transporter in Aspergillus nidulans. Proc Natl Acad Sci U S A 88, 204-8