Encyclopedia of Signaling Molecules

Living Edition
| Editors: Sangdun Choi

UT (Urea Transporter)

  • Mitsi A. Blount
  • Janet D. Klein
  • Jeff M. Sands
Living reference work entry
DOI: https://doi.org/10.1007/978-1-4614-6438-9_199-1

Synonyms

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...

Keywords

Urea Transporter Inner Medullary Collect Duct Acute Regulation Urea Permeability Phorbol Dibutyrate 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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References

  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.CrossRefPubMedPubMedCentralGoogle Scholar
  2. Blount MA, Klein JD, Martin CF, Tchapyjnikov D, Sands JM. Forskolin stimulates phosphorylation and membrane accumulation of UT-A3. Am J Physiol Renal Physiol. 2007;293:F1308–F13.CrossRefPubMedGoogle Scholar
  3. Blount MA, Mistry AC, Fröhlich O, Price SR, Chen G, Sands JM, et al. Phosphorylation of UT-A1 urea transporter at serines 486 and 499 is important for vasopressin-regulated activity and membrane accumulation. Am J Physiol Renal Physiol. 2008;295:F295–F9.CrossRefPubMedPubMedCentralGoogle Scholar
  4. Blount MA, Cipriani P, Redd SK, Ordas RJ, Black LN, Gumina DL, et al. Activation of protein kinase Calpha increases phosphorylation of the UT-A1 urea transporter at serine 494 in the inner medullary collecting duct. Am J Physiol Cell Physiol. 2015;309:C608–15. doi:10.1152/ajpcell.00171.2014.CrossRefPubMedPubMedCentralGoogle Scholar
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  20. Wang Y, Klein JD, Froehlich O, Sands JM. Role of protein kinase C-alpha in hypertonicity-stimulated urea permeability in mouse inner medullary collecting ducts. Am J Physiol Renal Physiol. 2013;304:F233–8. doi:10.1152/ajprenal.00484.2012.CrossRefPubMedGoogle Scholar

Copyright information

© Springer Science+Business Media LLC 2016

Authors and Affiliations

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