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Updated: Jul 10, 2026
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Quantitating Iron Transport Across the Mouse Placenta In Vivo Using Nonradioactive Iron Isotopes
Published on: May 10, 2022
Neither human hephaestin nor ceruloplasmin forms a stable complex with transferrin
David M Hudson1, Michael J Krisinger, Tanya A M Griffiths
1Centre for Blood Research and Department of Biochemistry & Molecular Biology, University of British Columbia, Vancouver, BC V6T 1Z3, Canada.
Journal of Cellular Biochemistry
|November 21, 2007
Summary
This study investigated if ferroxidases like ceruloplasmin and hephaestin directly bind to transferrin for iron transport. Results show no stable interaction, suggesting alternative mechanisms for iron loading during intestinal export.
Area of Science:
- Biochemistry
- Cell Biology
- Physiology
Background:
- Iron homeostasis is critical for health, preventing both deficiency and overload.
- Multicopper ferroxidases oxidize Fe(II) to Fe(III), preventing toxic hydroxyl-free radical generation.
- Hephaestin (Hp) is implicated in intestinal iron export, potentially interacting with transferrin (Tf).
Purpose of the Study:
- To investigate a potential protein-protein interaction between transferrin (Tf) and the ferroxidases ceruloplasmin (Cp) and hephaestin (Hp).
- To determine if Tf directly binds to Cp or Hp during intestinal iron export.
Main Methods:
- Native polyacrylamide gel electrophoresis
- Covalent cross-linking
- Surface plasmon resonance (SPR)
Main Results:
- No stable interaction or complex formation was detected between Tf and Cp.
- No stable interaction or complex formation was detected between Tf and a soluble form of recombinant human Hp.
- Experimental conditions did not reveal a direct protein-protein interaction.
Conclusions:
- A stable complex between Tf and these ferroxidases does not appear to occur.
- Alternative models are proposed for the loading of Tf with Fe(III) during intestinal iron export.
- The direct interaction hypothesis for Tf-Hp during intestinal iron export is not supported by this study.
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