Iron Imports. V. Transport of iron through the intestinal epithelium

Am J Physiol Gastrointest Liver Physiol. 2006 Mar;290(3):G417-22. doi: 10.1152/ajpgi.00489.2005.

Abstract

Iron absorption across the brush-border membrane requires divalent metal transporter 1 (DMT1), whereas ferroportin (FPN) and hephaestin are required for exit across the basolateral membrane. However, how iron passes across the enterocyte is poorly understood. Both chaperones and transcytosis have been postulated to account for intracellular iron transport. With iron feeding, DMT1 undergoes endocytosis and FPN translocates from the apical cytosol to the basolateral membrane. The fluorescent metallosensor calcein offered to the basolateral surface of enterocytes is found in endosomes in the apical compartment, and its fluorescence is quenched when iron is offered to the apical surface. These experiments are consistent with vesicular iron transport as a possible pathway for intracellular iron transport.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Animals
  • Caco-2 Cells
  • Cation Transport Proteins / physiology
  • Enterocytes / physiology
  • Humans
  • Intestinal Absorption / physiology*
  • Intestinal Mucosa / metabolism*
  • Iron / metabolism*
  • Iron-Binding Proteins / physiology
  • Membrane Proteins / physiology
  • Protein Transport / physiology
  • Rats

Substances

  • Cation Transport Proteins
  • Heph, protein, rat
  • Iron-Binding Proteins
  • Membrane Proteins
  • metal transporting protein 1
  • solute carrier family 11- (proton-coupled divalent metal ion transporters), member 2
  • Iron