Caroline C. Philpott Research Images
Iron homeostasis in yeast. Proteins expressed as part of the Aft1 and 2 regulon are labeled in black text. The low affinity iron transporters Smf1 and Fet4 are also shown. Genes that are down-regulated in iron deficiency are indicated in gray text.
Model of PCBP1 delivering iron to ferritin. PCBP1 binds 3 Fe(II) ions and binds to ferritin, delivering the iron for mineralization of the ferritin core.
PCBP iron chaperones in mammalian cells. Circulating iron is bound to transferrin (Tf), which in turn binds to transferrin receptor (TfR) on the surface of cells. The ferric Tf/TfR complex is internalized through endocytosis, and iron is released from transferrin and reduced to the ferrous form. Ferrous iron is transported to the cytosol through DMT1, where it can be bound by PCBP iron chaperones and delivered to ferritin or other cytosolic iron enzymes. Iron is also transferred to mitochondria for incorporation into heme and iron-sulfur clusters.
Page last updated: January 20, 2012