title: Chaperone turns gatekeeper: PCBP2 and DMT1 form an iron-transport pipeline.
abstract: How is cellular iron (Fe) uptake and efflux regulated in mammalian cells? In this issue of the Biochemical Journal, Yanatori et al. report for the first time that a member of the emerging PCBP [poly(rC)-binding protein] Fe-chaperone family, PCBP2, physically interacts with the major Fe importer DMT1 (divalent metal transporter 1) and the Fe exporter FPN1 (ferroportin 1). In both cases, the interaction of the Fe transporter with PCBP2 is Fe-dependent. Interestingly, another PCBP Fe-chaperone, PCBP1, does not appear to bind to DMT1. Strikingly, the PCBP2-DMT1 interaction is required for DMT1-dependent cellular Fe uptake, suggesting that, in addition to functioning as an intracellular Fe chaperone, PCBP2 may be a molecular 'gate- keeper' for transmembrane Fe transport. These new data hint at the possibility that PCBP2 may be a component of a yet-to-be-described Fe-transport metabolon that engages in Fe channelling to and from Fe transporters and intracellular sites.
authors: *Department of Pathology and Bosch Institute, Molecular Pharmacology and Pathology Program, Blackburn Building, University of Sydney, Sydney, New South Wales 2006, Australia.
authors: Darius J R
authors: DJ
authors: Lane
authors: *Department of Pathology and Bosch Institute, Molecular Pharmacology and Pathology Program, Blackburn Building, University of Sydney, Sydney, New South Wales 2006, Australia.
authors: Des R
authors: DR
authors: Richardson
mesh_terms: D027682:Cation Transport Proteins / Q000378:metabolism*; D006801:Humans; D007501:Iron / Q000378:metabolism*; D018832:Molecular Chaperones / Q000378:metabolism*; D016601:RNA-Binding Proteins / Q000378:metabolism*; D000099236:Solute Carrier Family 11, Member 2
chemical_list: D027682:Cation Transport Proteins; D007501:Iron; D018832:Molecular Chaperones; D016601:RNA-Binding Proteins; D000099236:Solute Carrier Family 11, Member 2; C501903:PCBP2 protein, human