HFE association with transferrin receptor 2 increases cellular uptake of transferrin-bound iron

Arch Biochem Biophys. 2008 Jun 1;474(1):193-7. doi: 10.1016/j.abb.2008.02.041. Epub 2008 Mar 7.

Abstract

Mutations in either HFE or transferrin receptor 2 (TfR2) cause decreased expression of the iron regulatory hormone hepcidin and hemochromatosis. HFE and TfR2 were recently discovered to form a stable complex at the cell membrane when co-expressed in heterologous cell lines. We analyzed the functional consequences of the co-expression of these proteins using transfected TRVb cells, a Chinese hamster ovary derived cell line without endogenous HFE or transferrin receptor. The co-expression of TfR2 in TRVb cells expressing HFE led to accelerated HFE biosynthesis and late-Golgi maturation, suggesting interaction prior to cell surface localization. The co-expression of HFE in cells expressing TfR2 led to increased affinity for diferric transferrin, increased transferrin-dependent iron uptake, and relative resistance to iron chelation. These observations indicate that HFE influences the functional properties of TfR2, and suggests a model in which the interaction of these proteins might influence signal transduction to hepcidin.

Publication types

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

MeSH terms

  • Blotting, Western
  • Cell Line
  • Cell Membrane / metabolism
  • Electrophoresis, Polyacrylamide Gel
  • Endocytosis*
  • Golgi Apparatus / metabolism
  • Hemochromatosis Protein
  • Histocompatibility Antigens Class I / metabolism*
  • Humans
  • Immunoprecipitation
  • Iron / metabolism*
  • Membrane Proteins / metabolism*
  • Receptors, Transferrin / metabolism*
  • Transferrin / metabolism*

Substances

  • HFE protein, human
  • Hemochromatosis Protein
  • Histocompatibility Antigens Class I
  • Membrane Proteins
  • Receptors, Transferrin
  • Transferrin
  • Iron