TCDB is operated by the Saier Lab Bioinformatics Group
TCIDNameDomainKingdom/PhylumProtein(s)
2.A.100.1.1









The iron exporter Ferroportin1 (Fnp1 or IREG1)

Eukaryota
Metazoa
Ferroportin (IREG1) of Mus musculus
2.A.100.1.2









The probable chloroplast Fe transporter, Mar1 (Conte et al., 2009)

Eukaryota
Viridiplantae
Mar1 of Arabidopsis thaliana (Q8W4E7)
2.A.100.1.3









Ferroportin1 or Iron-regulated protein1, 9FPN1, IREG1, ATIREG1; exports Fe2+, Co2+ and Ni2+ (Morrissey et al., 2009)

Eukaryota
Viridiplantae
FPN1 of Arabidopsis thaliana (O80905)
2.A.100.1.4









Solute carrier family 40 member 1 (Ferroportin-1; FPN1) (Iron-regulated transporter 1).  Transports iron, cobalt, zinc and manganese and maybe copper (Madejczyk and Ballatori 2012).  Regulated by its inhibitor, the processed liver antimicrobial peptide, hepcidin (TC# 8.A.37.1.2).  Tryptophan 42, a hemochromatosis type 4 disease residue, plays a role in iron export and iron homeostasis as well as hepcidin binding (Le Gac et al. 2013).  This protein has been modeled using the MSF EmrD of E. coli (TC# 2.A.1.2.9) (Le Gac et al. 2013). Defects can be corrected by adding the small molecule, hinokitiol (Cioffi et al. 2015; Grillo et al. 2017). The R178Q mutation is a recurrent cause of hemochromatosis and is associated with a novel pathogenic mechanism (Ka et al. 2018). The function of the "gating residues" in the mechanism of iron export have been modeled and studied (Guellec et al. 2019). Optimal conditions for Western blotting for this and other proteins requires that the sample not be boiled (Tsuji 2020).

Eukaryota
Metazoa
FPN1 or SLC40A1 of Homo sapiens
2.A.100.1.5









Ferroportin of 565 aas and 12 TMSs.

Eukaryota
Viridiplantae
Fpn of Chlorella variabilis (Green alga)
2.A.100.1.6









Uncharacterized ferroportin homolog of 560 aas and 14 TMSs, with two extra TMSs between the two 6 TMS repeat units.

Eukaryota
Oomycetes
UP of Peronospora effusa
2.A.100.1.7









Ferroportin1 (Fpn1) of 562 aas and 12 TMSs (Rafiee et al. 2012).  Missense mutations in Fpn1, an intestinal and macrophage iron exporter, have been identified between TMSs 3 and 4 in the zebrafish anemia mutant weissherbst (weh(Tp85c-/-)) and in patients with type 4 hemochromatosis.  Thus, ferroportin1 is required for normal iron cycling in both humans and zebrafish (Fraenkel et al. 2005).

Eukaryota
Metazoa
Fpn of Danio rerio (zebrafish)
2.A.100.2.1









Ferroportin of 440 aas and 12 TMSs. Transports Fe2+, Co2+, Mn2+ and Ni2+. The 3-d structures in both the inward and outward facing orientations have been determined, showing similarities to those of MFS permeases (Taniguchi et al. 2015). The Fpn family is a member of the MFS. Fpn-mediated iron efflux is stimulated by extracellular Ca2+ in the physiological range, even though  Ca2+ is not transported. Deshpande et al. 2018 determined the crystal structure of Ca2+-bound BbFpn (TC# 2.A.100.2.1), and found that Ca2+ is a cofactor that facilitates a conformational change critical to the transport cycle. They also identified a substrate pocket accommodating a divalent transition metal complexed with a chelator. These findings support a model of iron export by Fpn and suggest a link between plasma calcium and iron homeostasis (Deshpande et al. 2018).

Bacteria
Proteobacteria
Ferroportin of Bdellovibrio bacteriovorus
2.A.100.2.2









Uncharacterized Ferroporin homologue of 592 aas and 12 putative TMSs.

Eukaryota
Acytosteliales
UP of Acytostelium subglobosum