Function
Transferrin receptor (TfR) imports iron into the cell by receptor-mediated endocytosis of transferrin-iron complex. TfR is regulated by intracellular iron concentration. The amount of TfR expressed on the cell is proportional to the cell’s need for iron. The TfR has selective affinity for diferric-transferrin. The TfR-transferrin complex is internalized by the cell and iron is released to the cytosol. The TfR-apotransferrin complex returns to the extracellular surface where the apotransferrin dissociates and is replaced by diferric-transferrin[1].
Relevance
TfR is a potential determinant of iron loading in congenital anemias[2].
Structural highlights