What is the Origin of Transferrin Receptor?

Identified as a key component of systemic iron homeostasis, the receptor is named for the protein it binds, transferrin. Its discovery was fundamental to understanding the regulated transport of iron from the bloodstream into the intracellular compartment. The receptor's expression level is a dynamic cellular marker that reflects the cell's immediate iron needs, providing a critical insight into overall metabolic and cellular health.

What is the Mechanism of Transferrin Receptor?

The mechanism involves the receptor binding two molecules of iron-saturated transferrin at the cell surface, after which the entire complex is internalized into the cell via a process called receptor-mediated endocytosis. Inside the endosome, the low pH environment causes the iron to dissociate from the transferrin molecule. The free iron is then transported into the cytoplasm, while the transferrin receptor and the now iron-free transferrin are recycled back to the cell surface, ready to begin the cycle again, ensuring continuous and highly regulated iron delivery.

Transferrin Receptor ∞ Area

Transferrin Receptor

Meaning

The Transferrin Receptor (TfR) is a transmembrane glycoprotein expressed on the surface of virtually all human cells, with the highest density found on cells requiring substantial iron, such as developing red blood cells and rapidly proliferating cells. Its essential function is to mediate the cellular uptake of iron by binding to the iron-carrying plasma protein, transferrin. Iron is a critical micronutrient required for numerous metabolic processes, including mitochondrial function and hormone synthesis.