Reductive Release of Iron From Transferrin and Receptor Mediated Recycling
Mammalian cells acquire iron mainly by receptor mediated endocytosis of the iron transport protein transferrin and release of iron from the protein. The bulk of the experimental evidence at present suggests that the critical step for iron release is the acidification of the intracellular endocytic compartment, because lowering the pH significantly lowers the affinity of transferrin for iron. Apotransferrin is then recycled to the cell surface undegraded and released from the plasma membrane because of its low receptor binding affinity at pH above 7 (see 1,2 for review).
KeywordsK562 Cell Iron Uptake Pyridine Nucleotide Iron Release Reduce Pyridine Nucleotide
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