TCDB is operated by the Saier Lab Bioinformatics Group
TCIDNameDomainKingdom/PhylumProtein(s)
*1.A.28.1.1









Kidney vasopressin regulated urea transporter, UT-A2 (splice variant of UT-A1)
Eukaryota
Metazoa
UT-A2 of Rattus norvegicus
*1.A.28.1.2









Frog urinary bladder ADH-regulated urea transporter

Eukaryota
Metazoa
Urea transporter of Rana esculenta (O57609) 
*1.A.28.1.3









Kidney urea transporter, UT-A1 (mediates transepithelial urea transport in the inner medullary collecting duct for urinary concentration. Interacts with the C-terminus of Snapin (O95295) and SNARE-associated protein) (Mistry et al., 2007). Also transports formamide, acetamide, methylurea, methylformamide, ammonium carbamate, and acrylamide, and possibly dimethylurea and thiourea as well (Zhao et al., 2007). Mutation of the N-linked glycosylation sites reduces urea flux by reducing the UT-A1 half-life and decreasing its accumulation in the apical plasma membrane. The related erythrocyte urea transporter, UTB (UT-B; TC# 1.A.28.1.5) has been reviewed (Bagnasco, 2006).

Eukaryota
Metazoa
UT-A1 of Rattus norvegicus
*1.A.28.1.4









THe Urea transporter channel protein of 337 aas and 11 TMSs. The 3-d structure (2.3 Å resolution) is available (Levin et al., 2009).  Urea binding and flux as well as dimethylurea (DMU) transport have been modeled (Zhang et al. 2017).

Bacteria
Proteobacteria
Urea channel of Desulfovibrio vulgaris (A1VEP3)
*1.A.28.1.5









Urea transporter 1 or UT-B1 (Solute carrier family 14 member 1; Urea transporter of the erythrocyte) (Bagnasco 2006).  A phenylphthalazine compound, PU1424, is a potent UT-B inhibitor, inhibiting human and mouse UT-B-mediated urea transport with IC50 values of 0.02 and 0.69 mumol/L, respectively, and exerted 100% UT-B inhibition at high concentrations (Ran et al. 2016). UT-B catalyzes transmembrane water transport which can be ued as a reporter system (Schilling et al. 2016).  Knocking out both UT1 and UT2 increases urine output 3.5-fold and lowers urine osmolarity (Jiang et al. 2016). The double knockout also lowered blood pressure and promoted maturation of the male reproductive system. Thus, functional deficiency of all UTs causes a urea-selective urine-concentrating defect with few physiological abnormalities in extrarenal organs (Jiang et al. 2016).

Eukaryota
Metazoa
SLC14A1 of Homo sapiens
*1.A.28.1.6









Urea transporter 2 (Solute carrier family 14 member 2) (Urea transporter, kidney).  Knocking out both UT1 and UT2 increases urine output 3.5-fold and lowers urine osmolarity (Jiang et al. 2016). The double knockout also lowered blood pressure and promoted maturation of the male reproductive system. Thus, functional deficiency of all UTs causes a urea-selective urine-concentrating defect with few physiological abnormalities in extrarenal organs (Jiang et al. 2016).

Eukaryota
Metazoa
SLC14A2 of Homo sapiens
*1.A.28.1.7









Putative urea transporter of 306 aas and 9 TMSs

Bacteria
Proteobacteria
UT of E. coli
*1.A.28.2.1









The dimeric urea transporter, Utp (urea flux is saturable, could be inhibited by phloretin, and was not affected by pH; Raunser et al., 2009)

Bacteria
Proteobacteria
Utp of Actinobacillus pleuropneumoniae