Encyclopedia of Signaling Molecules

2018 Edition
| Editors: Sangdun Choi

UT (Urea Transporter)

  • Mitsi A. Blount
  • Janet D. Klein
  • Jeff M. SandsEmail author
Reference work entry
DOI: https://doi.org/10.1007/978-3-319-67199-4_199


Historical Background

Since 1934, it has been understood that urea plays a key role in the generation of concentrated urine (reviewed in Klein et al. 2011). Functional measurements of urea transport in the kidney inner medullary collecting duct (IMCD), performed in the 1980s, provided evidence for the existence of urea transporter proteins (reviewed in Klein et al. 2011). Currently, two families of urea transporters have been cloned: SLC14A1, the UT-B urea transporter originally isolated from erythrocytes; and SLC14A2, the UT-A group with six distinct isoforms described to date (reviewed in Klein et al. 2011) (Table 1). In the kidney, UT-A1 and UT-A3 are expressed in the IMCD; UT-A2 is expressed in the thin descending limb (tDL); and UT-B is located primarily in the descending vasa recta and red blood cells (Fig. 1). Although the exact location has yet to be determined, UT-A4 is expressed in rat kidney medulla but not in the...
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  1. Blessing NW, Blount MA, Sands JM, Martin CF, Klein JD. Urea transporters UT-A1 and UT-A3 accumulate in the plasma membrane in response to increased hypertonicity. Am J Physiol Renal Physiol. 2008;295:F1336–F41.PubMedPubMedCentralCrossRefGoogle Scholar
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Copyright information

© Springer International Publishing AG 2018

Authors and Affiliations

  • Mitsi A. Blount
    • 1
  • Janet D. Klein
    • 1
  • Jeff M. Sands
    • 1
    Email author
  1. 1.Renal Division, Department of Medicine, and Department of PhysiologyEmory UniversityAtlantaUSA