Premium
The alternate iron transport pathway: mobilferrin and integrin in reticulocytes
Author(s) -
Umbreit Jay N.,
Conrad Marcel E.,
Berry Michael A.,
Moore Elizabeth G.,
Latour Lydia F.,
Tolliver Beth A.,
Elkhalifa Mohamed Y.
Publication year - 1997
Publication title -
british journal of haematology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.907
H-Index - 186
eISSN - 1365-2141
pISSN - 0007-1048
DOI - 10.1046/j.1365-2141.1997.d01-2069.x
Subject(s) - reticulocyte , transferrin , transferrin receptor , ferric , chemistry , biochemistry , microbiology and biotechnology , integrin , receptor , biology , gene , organic chemistry , messenger rna
Iron transport in reticulocytes is known to occur via the well‐described transferrin‐receptor–endosome pathway. An alternative pathway for iron transport independent of transferrin has been postulated in reticulocytes and other cells. Transport of iron into reticulocytes from ferric citrate solutions was shown to be saturable and independent of transferrin. During transport of iron from ferric citrate, both cell surface integrins, and a soluble protein, mobilferrin, were labelled. This demonstrated that the reticulocyte transferrin independent pathway for iron transport involved integrins and mobilferrin similar to intestinal absorptive cells. This pathway would be expected to transport iron into cells under conditions of iron overload and was capable of providing iron for haemoglobin synthesis. Mobilferrin was also radiolabelled when radioiron labelled transferrin was incubated with reticulocytes and this occurred with a different time course than was observed following reticulocyte exposure to radiolabelled ferric citrate. This suggested that mobilferrin may serve as an intermediary in both pathways.