Pumping iron in the '90s

The role of iron in cell division, cell death and human disease has recently gained increased attention. The best studied process for iron uptake into mammalian cells involves transferrin and its receptor. This review discusses evidence supporting the existence of other routes by which iron can enter mammalian cells. Specifically, iron uptake by the cell-surface GPI-linked transferrin homologue, melanotransferrin or p97, is described and possible functions of this transferrin-independent pathway are proposed.