Home > A. Molecular pathology > TF
TF
MIM.190000 3q21
Monday 9 June 2003
Transferrin is a glycoprotein with an approximate molecular mass of 76,500 kD, 75,157 kD of which is contributed by a polypeptide chain of 679 amino acid residues.
Transferrin is the product of an ancient intragenic duplication that led to homologous carboxyl and amino domains, each of which binds 1 ion of ferric iron.
Transferrin carries iron from the intestine, reticuloendothelial system, and liver parenchymal cells to all proliferating cells in the body.
It carries iron into cells by receptor-mediated endocytosis. Iron is dissociated from transferrin in a nonlysosomal acidic compartment of the cell.
Provision of intracellular iron for synthesis of ribonucleotide reductase (MIM.180410), an enzyme that catalyzes the first step leading to DNA synthesis, is required for cell division.
After dissociation of iron, transferrin and its receptor return undegraded to the extracellular environment and the cell membrane, respectively.
Pathology
germline mutations in atransferrinemia (MIM.209300)