A) Alignment of primate hepcidins with those of other mammals, amphibians and fish. Residues identical to the human sequence are highlighted in grey. Part of the pro-peptide corresponding to the consensus propeptide convertase (furin) cleavage site is shown in italics. Arrows indicate the residues that are involved in the oligomerization of human hepcidin-25. (GeneBank accession numbers for non-primate species: Pig NM_214117; Mouse-1 BC_02158; Mouse-2 AY_232841; Rat NM_053469; Pigeon see ref. ; Frog DN_020182; Zebra fish NM_205583; Salmon BQ_036900; Bass DQ_31605). B) Structure of human hepcidin-25, based on the coordinate file 1M4F.pdb. The structure schematically shows the ladder-like disulphide connectivity (numbered Cys residues are indicated) and location of the variable stretch (residues 15–18) in light grey.