Ferritin stores iron Reduction of extracellular Fe3+ Oxidation of Fe2+ by ceruloplasmin Extracellular ferriheme uptake through the apical membrane of enterocytes Oxidation of Fe2+ by hephaestin apo-Transferrin is loaded with two iron ions Export of heme to the blood by ABCG2 Export of heme to the blood by FLVCR DCT1 (NRAMP2) mediates divalent iron uptake across the apical membrane of enterocytes Ferroportin mediates iron influx across the basolateral membrane of enterocytes Ferroportin mediates iron efflux on macrophages PathwayStep2622 PathwayStep4902 PathwayStep4901 PathwayStep4900 PathwayStep5024 PathwayStep5025 PathwayStep5009 PathwayStep5015 PathwayStep5013 PathwayStep5014 PathwayStep5011 PathwayStep5012 PathwayStep5010 The heme ring is cleaved by heme oxygenase Iron uptake and transport Authored: Stephan, R, 2010-06-30 Edited: Jassal, B, 2010-07-30 GENE ONTOLOGYGO:0006879 Pubmed18259769 Pubmed19381358 Pubmed20495089 Reactome Database ID Release 43917937 Reactome, http://www.reactome.org ReactomeREACT_25060 Reviewed: D'Eustachio, P, 2010-11-05 The transport of iron between cells is mediated by transferrin. However, iron can also enter and leave cells not only by itself, but also in the form of heme and siderophores. When entering the cell via the main path (by transferrin endocytosis), its goal is not the (still elusive) chelated iron pool in the cytosol nor the lysosomes but the mitochondria, where heme is synthesized and iron-sulfur clusters are assembled (Kurz et al,2008, Hower et al 2009, Richardson et al 2010). Transferrin endocytosis and recycling