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Localization of the urea transporter UT-B protein in human and rat erythrocytes and tissues

R T Timmer1, J D Klein, S M Bagnasco

  • 1Department of Physiology, Emory University School of Medicine, Atlanta, Georgia 30322, USA.

American Journal of Physiology. Cell Physiology
|September 8, 2001
PubMed

Insights

A new antibody reveals the urea transporter UT-B protein in human red blood cells, identifying it as the Kidd antigen. This transporter is also found in various rat tissues and kidney endothelial cells.

Area of Science:

  • Physiology
  • Molecular Biology
  • Immunology

Background:

  • The urea transporter UT-B plays a crucial role in maintaining osmotic balance.
  • Previous studies have limited understanding of UT-B expression patterns in various tissues.

Purpose of the Study:

  • To characterize the expression and distribution of the urea transporter UT-B protein.
  • To investigate UT-B presence in human erythrocytes and rat tissues.

Main Methods:

  • Utilized a novel polyclonal antibody against human erythrocyte UT-B.
  • Performed Western blot analysis on human erythrocytes and rat tissues.
  • Conducted immunohistochemical staining on kidney sections.
  • Detected UT-B mRNA in various rat tissues.

Main Results:

  • Detected UT-B protein in human erythrocytes (45-65 kDa), correlating with Kidd (Jk) antigen status.
  • Identified UT-B in rat erythrocytes (37-51 kDa) and multiple rat organs (brain, colon, heart, liver, lung, testis).
  • Observed UT-B in kidney medulla (41-54 kDa and 98 kDa bands) and vasa recta endothelial cells.

Conclusions:

  • UT-B protein is expressed in human erythrocytes and is associated with the Kidd antigen.
  • UT-B exhibits a broader tissue distribution in rats than previously documented.
  • The findings provide new insights into UT-B's physiological roles and localization.

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