SLC40A1:HEPH:6Cu2+ transports Fe2+ from cytosol to extracellular region

Stable Identifier
Reaction [transition]
Homo sapiens
Ferroportin mediates iron influx across the basolateral membrane of enterocytes
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The primary site for absorption of dietary iron is the duodenum. Ferrous iron (Fe2+) is taken up from the gut lumen across the apical membranes of enterocytes and released into the portal vein circulation across basolateral membranes.
The human gene SLC40A1 encodes the metal transporter protein MTP1 (aka ferroportin or IREG1). This protein resides on the basolateral membrane of enterocytes and mediates ferrous iron efflux into the portal vein (Schimanski et al. 2005). MTP1 colocalizes with hephaestin (HEPH) which stablizes MTP1 and is necessary for the efflux reaction to occur (Han & Kim 2007, Chen et al. 2009). As well as the dudenum, MTP1 is also highly expressed on macrophages (where it mediates iron efflux from the breakdown of haem) and the placenta (where it may mediate the transport of iron from maternal to foetal circulation). It is also expressed in muscle and spleen.
Literature References
PubMed ID Title Journal Year
15692071 In vitro functional analysis of human ferroportin (FPN) and hemochromatosis-associated FPN mutations

Viprakasit, V, Cowley, D, Bastin, JM, Schimanski, LM, Robson, KJ, Townsend, AR, Chinthammitr, Y, Merryweather-Clarke, AT, Drakesmith, H, Sweetland, E, Edwards, JP

Blood 2005
17486601 Colocalization of ferroportin-1 with hephaestin on the basolateral membrane of human intestinal absorptive cells

Kim, EY, Han, O

J Cell Biochem 2007
19452451 Decreased hephaestin expression and activity leads to decreased iron efflux from differentiated Caco2 cells

Vulpe, C, Attieh, ZK, van der Hee, RM, Huang, G, Chen, H, Dang, T

J Cell Biochem 2009
Catalyst Activity

ferrous iron transmembrane transporter activity of SLC40A1:HEPH:6Cu2+ [plasma membrane]

Orthologous Events
Cross References
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