Transferrinmediated

Transferrinmediated refers to processes or phenomena that are facilitated or regulated by transferrin. Transferrin is a metalloprotein found in the blood plasma of vertebrates. Its primary function is to transport iron. Iron is an essential element for many biological processes, including oxygen transport by hemoglobin, DNA synthesis, and cellular respiration. However, free iron is toxic due to its ability to catalyze the formation of reactive oxygen species. Transferrin binds to iron in a high-affinity manner, forming diferric transferrin, and delivers it to cells that express transferrin receptors.

The transferrinmediated uptake of iron by cells is a crucial pathway for maintaining cellular iron homeostasis. Cells express transferrin receptors (TfR) on their surface, which bind to diferric transferrin. This complex is then internalized through receptor-mediated endocytosis. Once inside the cell, the iron is released from transferrin within endosomes, a process dependent on the acidic environment of the endosome and the activity of proteins like Steap3. The released iron can then be utilized by the cell or stored in ferritin.

Beyond iron transport, transferrin also plays a role in the immune system by limiting the availability of free iron, which is essential for the proliferation of many pathogenic microorganisms. Transferrinmediated processes are therefore important for both cellular nutrition and host defense. Dysregulation of transferrinmediated iron uptake can lead to various health conditions, including iron deficiency anemia and hereditary hemochromatosis.