Pflügers Archiv

, Volume 447, Issue 5, pp 641–646 | Cite as

SLC19: the folate/thiamine transporter family

  • Vadivel Ganapathy
  • Sylvia B. Smith
  • Puttur D. Prasad
The ABC of Solute carriers Guest Editor: Matthias A. Hediger

Abstract

The SLC19 gene family of solute carriers is a family of three transporter proteins with significant structural similarity, transporting, however, substrates with different structure and ionic charge. The three members of this gene family are expressed ubiquitously and mediate the transport of two important water-soluble vitamins, folate and thiamine. The concentrative transport of substrates mediated by the members of this gene family is energized by transcellular H+/OH gradient. SLC19A1 is expressed at highest levels in absorptive cells where it is located in a polarized manner either in the apical or basal membrane, depending on the cell type. It mediates the transport of reduced folate and its analogs, such as methotrexate, which are anionic at physiological pH. SLC19A2 is expressed ubiquitously and mediates the transport of thiamine, a cation at physiological pH. SLC19A3 is also widely expressed and is capable of transporting thiamine. This review summarizes the current knowledge on the structural, functional, molecular and physiological aspects of the SLC19 gene family.

Keywords

Folate Thiamine Transport Solute carrier Homeostasis Homology 

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Copyright information

© Springer-Verlag  2004

Authors and Affiliations

  • Vadivel Ganapathy
    • 1
  • Sylvia B. Smith
    • 2
  • Puttur D. Prasad
    • 3
  1. 1.Department of Biochemistry and Molecular BiologyMedical College of GeorgiaAugustaUSA
  2. 2.Department of Cellular Biology and AnatomyMedical College of GeorgiaAugustaUSA
  3. 3.Department of Obstetrics and GynecologyMedical College of GeorgiaAugustaUSA

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