Expression pattern of hemochromatosis genes in RPE. TfR, transferrin receptor; HFE, HLA-like protein involved in iron homeostasis; Fp, ferroportin; Hp, hephaestin; Cp, ceruloplasmin; HJV, hemojuvelin; BMP, bone morphogenic proteins; BMPR, BMP receptors. It is speculated that secretion of hepcidin from RPE may be directional, preferentially into the subretinal space across the apical membrane.